Development of an OF-CEAS laser spectrometer for water vapor isotope measurements at low water concentration

A PhD thesis completed in a co-tutelle arrangement between the J. Fourier University (Grenoble I) and the University of Groningen Felix Janek Landsberg he disserttion presented in the following would not hve een possile without the sienti(D personl nd (nnil support of quite numer of people nd orgniztionsD whom s would like to thnk espeilly in the followingF pirst of llD s wnt to thnk my supervisor in qrenoleD irik uerstelD for his strong supportD his good ides nd helpful propositions throughout the yers of this thesisF wny thnks lso to hniele omniniD my oEsupervisorD who lwys hd vlule omments nd helpful hndD espeilly onerning ll prolems relted to the ypEgie tehniqueF s lso would like to thnk my supervisor in qroningenD rrro weijerD who supported me E due to the ft tht s spent the mjority of my thesis in qrenole E often per distne nd vi eEmil nd lwys showed gret interest in the dvnement of my thesisF n très grnd meri à mir ussiD qui m9 idé euoup ve une multitude des prolèmes et modi(tions onernnt le logiiel view pour fire tourner les instruments et ve des prolèmes onernnt l9instrument ypEgieF te voudris ussi remerier hiult hesoisD qui m9 idé euoupD spéilement u déut de m thèse en m9introduisnt dns l tehnique ypEgie et en me forçnt de fire et introdution en prnçisD el m9 euoup idé á méliorer mon prnçis3 te voudris ussi remerier erge féguierD qui m9 ssisté ve les prolèmes informtiques et qui fit plusieurs logiiels indispensles dns view et meri ussi á tenEvu wrtin qui m9 idé ptiemment ve des prolèmes életroniquesF weri ussi à mes oEdotornts wrine pvier et wthieu gsdoD qui ont pris le relis ve les instruments developpés dns ette thèseD qui se sont oupés des expérienes dns les dernières semines de m thése et qui ont pris soin que les instruments seront utiliser dns le futurF fernrd ghelli one de veon et wihel hijsD qui ont fit des stges ve moiD m9ont idé ve des trveux dns le lortoire et fernrd ussi pendnt une mpgne de mesure à gréteilD meri euoup ussi pour elF te voudris ussi dire meri à tout l9àtelier méhnique u vshyD qui m9 idé euoup ve l frition des pièes méhniques ompliqués et souvent ve des onseils qund j9i friqué vii des pièes moiEmemeF weri ussi à tout l9équipe vesersD woléules et invironnement @vewiA du vshy pour l9intégrtion hleureux dns l9équipe et euoup des disussions frutueuxF s would lso like to thnk the swuEeep group of the urlsruhe snstitute of ehnology for their support during four mesurement mpigns t the eshe loud hmer in urlsruheF ispeilly thnks to rrld tho'D yttmr woehler nd xruki rirnum for very friendly nd vlule ollortion nd mny good ides onerning our joint experimentsF e speil thnks to tn rigD former hh student in the swuEeep groupD with whom s spent numerous weeks of shred workD oth in qrenole nd urlsruhe nd hd mny fruitful disussionsF e gret thnks lso to viz woyerD iri tutzD ur vmD vzlo rkozy nd fen glouser from the heprtment of qeophysil iene of the niversity of ghigo for the good ollortion during the mesurement mpigns in urlsruheD thnks lot ur for the modelling nd dtD iri for the joint work with our lirtion systemsD oth in urlsruhe nd qrenole nd viz for very helpful ommentsF hnk you to fenjmin uühnreihD teven gner nd olker iert for the joint work t the eshe loud hmer nd prtiulrly thnks to fenjmin for severl stimulting nd helpful disussionsD oth during the mpigns nd fterwrdsF te voudris ussi remerier emelle vndisD ylivier gttni et préderi rie du vortoire des ienes du glimt et de l9invironnement @vgiA á qifEsurEvette pour l ollortionF ylivier m9 donné des onseils indispensles sur le developpement du système de lirtion et m9 généreusement prêté un système de lirtion pour l mpgne de mesure en entrE tiqueF weri euoup à emelle et préderi pour l mpgne de mesure onjoint á gréteil et les disussions sienti(ques vnt et prèsF usen tkk lso to the xorwegin olr snstituteD without whom the mesurement mpign to entrti would never hve een possileF s would espeilly like to thnk iliseth ssksson nd uim rolmén for the preEorgniztion nd uen ederson nd er irik rnevold for the help during my sty t roll sttionF sn this ontextD s lso would like to thnk ghris vunder from the xorwegin snstitute for eir reserh @xsvAD who generously provided me with environmentl dt for the mesurement period t rollF por the (nnil supportD s would like to thnk the xetherlnds yrgnistion for ienti( eE serh @xyA for the funding of three yers of my hh thesis in the frmework of xee projetD inluding the mesurement mpign to roll nd vrious sienti( instrumenttionF hnks lso to the niversity tp of qrenole s for the funding of sienti( equipment under the uerstel instlltion grnt nd the ijksuniversiteit qroningen for the (nning of n ddiE tionl yer of my thesisF gonerning the sygvyh mpignD s m thnkful to hve indiretly prtiipted of the xp nd hpq qis funding s well s of iygrewEP funding for the trvel expensesF eprt from the sienti( nd (nnil supportD s would like to thnk numer of dditionl peoE ple for their personl support during the time of my thesisF e very gret thnk you to my wife viii weike ulosterEvndsergD who supported me in every wy during my entire thesis nd without whom mny prts would hve een muh more di0ult or even impossileF s lso would like to thnk my fmily nd weike9s fmily for their support during ll this time nd their sympthy in ll spetsF pinlementD je voudris ussi remerier wustph fouli et l9ensemle vol de qrenoleD ve qui j9i pssé euoup de temps très gréle pendnt mon temps à qrenoleD à l fois musiE lement et personnellementF v musique m9 ressouré hque foisF ix Summary sn reent yersD the mesurement of wter isotopologues hs eome inresingly importnt for tmospheri reserhF hue to the in)uene of limti onditions on the isotope rtiosD the isotopi omposition of wter stored in the ie in entrti nd the erti n e used s pleothermometers to reonstrut pst limte hnges IF he mesurement of hnges of the isotopi omposition of wter vpor in the tmosphere n e used to study the glol hydrolol hydrologi yle P nd to re(ne tmospheri irultion models QF heres the onventionl method for wter isotope mesurementsD ssotope tio wss peE trometry @swAD is not dpted for inEsitu ontinuous mesurements of wter vpor isotopesD the reent development of lser spetrometers o'ers omprly esy nd roust method to ondut inEtheE(eld reserh with good time resolution R!UF roweverD until nowD most optil instruments require reltive high humidity levels with wter onentrtions of t lest severl IHHH ppmvD whih exludes mesurements in some of the most interesting regions for wter isotope reserhD suh s the upper tmosphere nd the entrl regions of entrtiF sn this workD we present novel infrred lser spetrometer sed on yptil peedk gvity inhned esorption spetrosopy @ypEgieAD spei(lly designed to mesure the four isotopologues r 2 16 yD r 2 18 yD r 2 17 y nd rh 16 y under very dry onditionsD t wter onentrtions of some hundred to only tens of ppmvF he instrument developed during this thesis shows muh higher mesurement stility over time ompred to previous ypEgie instruments with optimum integrtion times of up to severl hours nd very long e'etive pth length of more thn QH kmF et wter onentrtions round VH ppmvD preision of HFV D HFI nd HFP for δ 2 rD δ 18 y nd δ 17 y respetively ould e hieved with n integrtion time of QH min nd of IP D IFI nd QFP with Rs vergingF et the optimum wter onentrtion of pproxF TSH ppmvD the preision for δ 2 rD δ 18 y nd δ 17 y is HFPV D HFHP nd HFHU respetivelyD with verging times of QH to TH minF en investigtion of the overll performne of the instrument is presented nd we spei(lly disuss the prolem of dependene of the isotope mesurements on the wter onentrtion t xi ummry whih mesurement is rried outF es min soure of the onentrtion dependeneD pttern noise is identi(ed nd detiled nlysis of the noise soures is givenF purthermoreD new lirtion system for wter vpor isotope mesurementsD the yringe xnoliter snjetion glirtion ystem @xsgAD is introduedD whih ws developed in the frmework of this thesis to o'er more relile nd stle mens for the lirtion of wter vpor isotope mesurementsF his lirtion system is sed on the ontinuous injetion of wter into n evportion hmer with two nnoliter syringe pumps nd is le to generte stndrd wter vpor in rnge of S to IS HHH ppmvF e model simultion of the wter injetion is presented nd shows good greement with experimentl resultsF usequentlyD (rst employment of the ypEgie spetrometer t the xorwegin reserh sttion of roll in entrti is disussedF ht from threeEweek period from perury nd wrh PHIID during whih the spetrometer ontinuously mesured wter vpor isotopologues in the tmosphere t the reserh sttionD is shown nd prolems nd possiilities re disussedF pinllyD the ssoloud projetD n interntionl projet to study @superAsturtion e'ets t the eshe loud hmer of the urlsruhe snstitute ehnology in qermnyD is introduedD in whih we prtiipted with oth the spetrometer nd the lirtion instrumentF ixperimentl dt of the four mesurement mpigns is presentedD preliminry results re disussedF e onlude with disussion of the optimum mesurement protool nd give n outlook for the futureF xii Résumé eu ours de es dernières nnésD l mesure des isotopologues de l9eu est devenue de plus en plus importnte dns le domine des sienes de l9tmosphèreF v omposition isotopique de l9eu onservée dns l gle en entrtique et en ertique peut être utilisée omme un pléothermomètre permettnt de omprendre les hngements pssés du limt I du fit de l9in)uene des onditions limtiques sur les rpports isotopiquesF v mesure des vritions de l omposition isotopique de l vpeur d9eu dns l9tmosphère peut servir à étudier le yle hydrologique glol de l terre P et à r0ner les modèles de irultions tmosphériques QF v petrométrie de wsse des pports ssotopiques @plus souvent onnu pr son ronyme nglis swAD qui est l méthode onventionnelle pour l mesure des isotopes de l9euD n9est ps dptée ux mesures en ontinu et inEsitu des isotopes de vpeur d9euF g9est grâe u développement réent des spetromètres lserD qu9il existe mintennt une méthode simple et rouste pour e'etuer des reherhes sur le terrin ve une onne résolution temporelle R! UF gependntD jusqu9à présent l pluprt des instruments optiques usuels exigent des niveux d9humidité reltivement élevés ve des onentrtions d9eu supérieures à IHHH ppmvD e qui exlut les mesures dns ertines des régions les plus intéressntes pour l9étude des vritions isotopiques dns l9euD telles omme les ouhes élevées de l9tmosphère ou les régions entrles de l9entrtiqueF

ge trvil à pour ut d9introduire un nouveu spetromètre lser infrrouge sé sur l tehE nique d9yptil peedk gvity inhned esorption spetrosopy @ypEgieAF sl été onçu spéilement pour l mesure des qutre isotopologues r 2 16 yD r 2 18 yD r 2 17 y et rh 16 y dns un environnement se ve des onentrtions d9eu de quelques entines à seulement quelques dizines de ppmvF v9instrument développé dns le dre de ette thèse montre une stilité de mesure supérieure ux instruments ypEgie préédentsD ve des temps d9intégrtion optiE mux pouvnt ller jusqu9à plusieurs heures et une longueur de trjet optique e'etive de plus de QH kmF our des onentrtions d9eu d9environ VH ppmv D une préision de HFV D HFI et HFP été tteinte respetivement pour δ 2 rD δ 18 y et pour δ 17 y ve un temps d9intégrtion de xiii ésumé QH minutes et de IP D IFI nd QFP ve une moyenne e'etuée sur RsF our l onentrtion d9eu optimle de TSH ppmvD l préision pour δ 2 rD δ 18 y et δ 17 y est de HFPV D HFHP et de HFHU D ve une durée d9umultion de QH à TH minutesF v performne glole de l9instrument est nlysée et le prolème de l dépendne des mesures isotopiques visEàEvis de l onentrtion d9eu ve lquelle l9expériene est e'etuée est étudié en détilF v présene d9un motif (xe spetrl est identi(ée omme étnt l soure prinE iple de ruit et est nlysée en détilF in outreD un nouveu système de lirtion pour des mesures d9isotopes de vpeur d9euD le yringe xnoliter snjetion glirtion ystem @xsgAD est présentéF ge système été développé dns le dre de ette thèse (n de disposer d9un moyen (le et stle pour l lirtion des mesures des vritions isotopiques de l vpeur d9euF ve système de lirtion est sé sur l9injetion ontinue d9eu dns une hmre d9évportion ve deux pousseEseringues u nnolitreF sl est ple de générer une vpeur d9eu stndrd entre S et ISHHH ppmvF ne simultion modélisée de l9injetion d9euD qui est en on ord ve les expérienesD est présentéeF insuite une première utilistion du spetromètre ypEgie dns l sttion de reherhe norvégienne @rollA en entrtique est exposée en détilF ves données enregistrées pendnt une période de trois semines de pévrier à wrs PHII sont présentées et disutéesD en prtiulier elles reltives ux prolèmes de lirtion renontrés ve un système de lirtion rudimentire onstruit sur pleF endnt ette période le spetromètre mesuré en ontinu les isotopologues de vpeur d9eu dns l9tmosphère sur le site de l sttionF our onlureD nous présentons le projet ssoloudD un projet interntionl ynt pour ut d9étudier des e'ets de @superAsturtion en utilisnt l hmre à nuges eshe du urlsruhe snstitute of ehnology en ellemgneF xotre spetromètre et le système de lirtion fisient prtie de e projetF ves données expérimentles de qutre mpgnes de mesure sont présentées et des résultts préliminires sont disutésF xous onluons en présentnt un protoole optiml de mesure optiml insi que pr une disussion des perspetives pour le futurF xiv Samenvatting he epling vn de isotopensmenstelling vn wterdmp heeft zih in de fgelopen jren onE twikkeld tot een steeds elngrijker nlytish instrument in tmosferish onderzoekF he invloed vn klimtftoren op de isotoopverhoudingen mkt dt de isotopensmenstelling vn wter opgeslgen in entrtish en ertish gletsjerijs geruikt kn worden ls een pleoEthermometer in de reonstrutie vn klimtvernderingen in het verleden IF he isotoopverhoudingen in wterdmp in de tmosfeer levert informtie over de @zoetEA wter kringloop P en is een eE lngrijk gegeven voor de verdere ontwikkeling vn tmosferishe irultie modellen QF hr wr de onventionele meetmethode voor de epling vn isotoopverhoudingenD ssotopen tio wss petrometrie @swAD niet geshikt is voor inEsitu epling vn isotoopverhoudingen in wterdmpD ieden reente methoden geseerd op lser spetrometrie de mogelijkheid om op reltief eenvoudige en rouuste instrumenttie te ouwen voor meting in het veld met hoge tijdsresolutie R!UF ihterD de meeste vn deze optishe instrumenten vereisen een reltief hoge luhtvohtigheid met wter onentrties vn tenminste enkele duizenden ppmv @volumeonenE trtie in delen per miljoenAD wrdoor metingen in enkele vn de meest interessnte regio9s op rdeD zols in de hogere tmosferishe lgen of in entrl entrtiD onmogelijk zijnF hit proefE shrift eshrijft de ontwikkeling vn een innovtieve infrrood lser spetrometer welke geruik mkt vn de methode vn yptil peedk gvity inhned esorption petrosopy @ypE gieA voor de kwntittieve epling vn de vier wterisotopologen r 2 16 yD r 2 18 yD r 2 17 y en rh 16 y in zeer droge luht ij wteronentrties vn enkele honderden tot slehts tientllen ppmv9sF ret door ons ontwikkelde instrumentD vergeleken met eerdere ypEgie instrumentenD wordt gekenmerkt door een veel lngere meetstiliteit in de tijd met een optimle middelE ingstijd tot enkele uren en een grote gevoeligheid ten gevolge vn de extreem lnge optishe weglengte vn ruim QH kmF fij een wteronentrtie vn VH ppmv is de meetpreisie HFV D HFI en HFP voor dPrD dIVy en dIUyD respetievelijkD ij middeling over QH minD en IP D IFI en QFP ij middeling over R sF fij de optimle wteronentrtie vn ongeveer TSH ppmv is de preisie voor δ 2 rD δ 18 y en δ 17 yD respetievelijkD gelijk n HFPV D HFHP en HFHU ij xv menvtting middeling over QH tot TH minF e presenteren een lgemene krkterisering vn het instruE mentD lsook een gedetilleerde eshrijving vn de fhnkelijkheid vn de isotopenmetingen vn de wteronentrtie ij welke de metingen worden uitgevoerdF els elngrijkste oorzk vn deze onentrtiefhnkelijkheid wijzen we nr het gestrutureerde krkter vn de instruE mentele ruis op de htergrond @sislijnA vn het wterspetrum welke geruikt wordt voor de epling vn de isotopenverhoudingenF ret e'et vn dit ptroonruis9 op de metingen is verder onderzohtF eneinde de spetrometer te kunnen klireren is een luhtstroom met een stiele wteronentrtie en isotopensmenstelling vereistF ymdt ekende methoden voor de produtie vn een dergelijke vohtige luhtstroom niet voldoende etrouwr en stiel leken te zijn ij de door ons gewenste lge wteronentrtiesD is in het kder vn dit proefshrift een lterntief instrument ontwikkeld genmd xsg @voor yringe xnoliter snjetion glirE tion ystemAF hit systeem is geseerd op twee ommeriële nnoliter spuitspompen teneinde wteronentrties vn S tot IS HHH ppmv te kunnen genereren met een zo lg mogelijke onE sumptie vn de vk kostre wter isotopen stndrdenF ien simpel model geeft een goede kwntittieve eshrijving vn geïndueerde vernderingen in zowel onentrtie ls isotopenE verhoudingenF ervolgens wordt een uitgereide eshrijving gegeven vn de eerste toepssing vn de spetrometer in entrtiD op het xoors sttion rollD wrij dt vn een periode vn Q weken in feruri en mrt vn PHII worden gepresenteerdF ot slot espreken we de deelnme vn de spetrometer en zijn klirtie pprtuur n het interntionle projet sygvyh ter estudering vn @superA sturtie e'eten tijdens wolkvorming in de eshe simultiekmer vn het urlsruhe snstitute of ehnologyF e lten experimentele dt vn R meetmpgnes en de eerste resultten zienF e esluiten met een espreking vn de optimle meetstrtegie en geven een lik op de toekomstF xvi

Contents

Introduction 1

1 Isotope terminology 3

IFI turtion wter vpor pressure F F F F F F F F F F F F F F F F F F F F F F F F F F F F Q IFP ssotopes F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F R IFPFI ssotope rtios F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F R IFPFP prtiontion F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F T IFPFQ helt vlues s proxies F F F F F F F F F F F F F F F F F F F F F F F F F F F F F W 2 Measurement of isotopes 13 PFI wss spetrometry F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F IQ
PFP he optil lterntiveX tle ssotope tio snfrred petrosopy F F F F F F F F IR PFQ yptil petrosopy ehniques

F F F F F F F F F F F F F F F F F F F F F F F F F F F IT PFR tteEofEtheErt F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F PI PFS yptil feedk vity enhned sorption spetrosopy @ypEgieA F F F F F F PQ PFT esorption sle linerity F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F PT 3 OCEAS instrument design 29 QFI yptil vyout F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F PW QFP wehnil lyout F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F QH QFQ plow system F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F QH QFR ht quisition nd storge F F F F F F F F F F F F F F F F F F F F F F F F F F F F F QI QFS ystem ontrol nd house keeping F F F F F F F F F F F F F F F F F F F F F F F F F F F QI QFT ghoie of spetrl rnges F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F QP xviii gontents
Data analysis procedures 37

RFI enlysis of experimentl spetr F F F F F F F F F F F F F F F F F F F F F F F F F F F QW RFP reision F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F QW RFQ xoise nlysis F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F RQ RFR hotodetetor linerity F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F RT RFS ower sturtion F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F RW RFT wtrix e'ets F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F SP RFU gonlusion F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F SS
Data Corrections and Calibration 57

SFI glirtion strtegy F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F TI SFIFI gonentrtion dependene in other spetrl rnges F F F F F F F F F F F F F UI Calibration instruments 73 TFI wirodrop injetor F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F UT TFP yringe xnoliter snjetion glirtion ystem F F F F F F F F F F F F F F F F F F F UU TFPFI wodeling of the syringe injetion F F F F F F F F F F F F F F F F F F F F F F F UV TFPFP gomprison with experimentl dt F F F F F F F F F F F F F F F F F F F F F VI TFPFQ glirtion with two syringe pumps F F F F F F F F F F F F F F F F F F F F F VP
Water vapor isotopologues in Antarctica 87

UFI he entrti spetrometer design F F F F F F F F F F F F F F F F F F F F F F F F F F VU UFP vol setEup F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F VW UFQ glirtion proedure F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F WH UFQFI yringe pump lirtion F F F F F F F F F F F F F F F F F F F F F F F F F F F WH UFQFP fuler F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F WQ UFQFQ glirtion mesurements t roll ttion F F F F F F F F F F F F F F F F F F WT UFR wesurement F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F IHH UFRFI fktrjetories F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F IHP UFS gonlusion F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F IHP
Water isotope fractionation in simulated ice clouds 111

Introduction etmospheri wter vpor is the most importnt greenhouse gs nd responsile for pproxiE mtely TH7 of the nturl greenhouse e'et VF he sptil distriution of wter vpor nd the prtitioning etween vpor nd liquid phse ply n importnt role in the rditive lne of the tmosphere WD IHF hse trnsitions etween vpor nd liquid or solid phse re determinE ing loud formtion nd preipittionD nd present the si mehnism of tmospheri energy trnsportF he reltive undnes of the di'erent stle isotopologues of wter re sensitive to the ondiE tions t whih phse hngesD nd evportion nd ondenstion in prtiulrD tke pleF he isotopi omposition of preipittion t higher ltitudes is relted to ir temperture II!IQF feuse of thisD wter isotopi rtios o'er unique possiility to study proesses tht would otherwise remin hiddenF ter isotopi rtios n e used s trers of the tmospheri wter yle IR nd for the study of onvetive proesses in the tmosphere IS!IVF hue to the in)uE ene of limti onditions on the isotope rtiosD the isotopi omposition of wter stored in the ie in entrti nd the erti n e used to reonstrut pst limte hnges ID IWD PHF gonventionllyD isotope rtio mesurements re onduted y mens of ssotopeEtio wss peE trometry @swA F feuse of elorte nd time onsuming preprtion of the smples nd the impossiility of inEsitu mesurements @fF lso PFIAD optil spetrosopy is inresingly used s lterntiveD espeilly when ontinuous nd inE(eld mesurements re requiredF sn reent yersD diverse lser spetrometers sed on di'erent optil tehniques hve een introdued @eFgF the referenes R!UD IHD s well s setion PFR of this thesis for more detiled disussionA nd suessfully ppliedF roweverD to the est of our knowledgeD so fr no instrument hs een le to mesure isotope rtios in very dry onditions @`SH ppmvA enountered in the upper tmosphereD with su0iently high preision to resolve mirophysil proesses responsile for some of the most interesting mehnisms in irths tmosphereD suh s supersturtionF his thesis ws initited in the frmework of the huth xtionl enterti eserh rogrm @xeeA nd funded to lrge extend y the xetherlnds yrgniztion for ienti( eserh P sntrodution @xyAF edditionl funding ws given y the the sntegrtion of iuropen imultion ghmE ers for snvestigting etmospheri roesses @iygrewEPAF vol funding ws generously provided y the niversité toseph pourier @tpAF he gol ws to develop novel infrred lser spetrometer to mesure stle wter isotopes nd the susequent pplition to limte reserhD spei(lly y mesuring wter vpor isotopes in the entrti tmosphereF efter (rst mesurement mpign to entrtiD n dditionl fous ws set on the developE ment of roust nd relile lirtion setEup for very low wter onentrtion lirtions of isotopi mesurementsF snresed ttention ws lso given to more inEdepth study of noise hrteristis of the spetrometer itselfF purthermoreD the pplition of the instrument ws expnded to study mehnisms enountered in the tmosphereF hese investigtions were rE ried out t the loud hmer eshe in urlsruheD qermny in the frmework of the soElled ssoloud projetF sn hpter ID generl introdution to the terminology of wter vpor isotopologues is givenD explining the underlying mehnisms nd priniplesF sn hpter PD we give n overview of the trditionl nd reent methods used to study wter vpor isotopologues nd in hpter QD the priniples nd lyout of the lser spetrometer developed in this thesis re explinedF ghpter R explins how the dt reorded with the lser spetrometer is nlyzed nd onverted to onentrtion nd isotope rtio vluesF purthermoreD the preision nd ury of the instruE ment re disussedF e proedure for the lirtion of the dt is introdued in hpter SF sn hpter TD di'erent lirtion instruments re introdued tht were used nd prtly developed during the thesis to put the isotopi mesurements on n solute sleF (1.1) pice = exp(9.550426 -5723.265/T + 3.53068 ln(T) -0.00728332T)

(1.2)

with in uelvin nd p in pslF he eqution for sturtion pressure ove wter is vlid for 123 < T < 332 u nd the eqution for ie for T > 110 uF sf the prtil pressure of wter is higher thn the sturtion pressureD this is lled supersturE tionF he phenomen of supersturtion is quite ommon in the sene of nuletion enters @eFgF erosolsA on whih the vpor n ondense or freeze outD ut hs lso een oserved when nuletion enters re present @disussed in more detil in hpter VAF he sturtion prmeter

S = p H2O p saturation @IFQA
is used to express the degree of sturtionD with supersturtion for S > 1F

1.2 Isotopes etoms onsist of nuleus surrounded y eletronsF he nuleus is omposed y protons nd neutronsF he protons re positively hrged nd determine y their numer @the tomi numE erAD whih hemil element the tom elongs toF he neutrons rry no eletri hrge nd determine long with the protonsD whih hve pproximtely the sme mssD the mss of n tomF he sum of the numer of protons @A nd neutrons @xA in nuleus is the nuler mss numerX

A = Z + N @IFRA
he ommon nottion to desrie spei( nuleus of element isX

A Z X N
wo toms of the sme element @sme numer of protonsA ut di'erent numer of neutronsD re lled isotopesF wny elements hve two or more stle nd nturlly ourring isotopesF eprt from stle isotopesD some elements lso hve unstle @rdiotiveA isotopes tht only hve smll hne of nturl ourreneF sn the se of hydrogenD two stle isotopes existX 1 r nd 2 1 r 1 @lso lled deuteriumAF e third isotope 3 2 r 2 @tritiumA is rdiotiveF yxygen hs three stle isotopesD the most undnt 16 y nd two rre isotopesD 18 y nd 17 yF sn the se of moleules with di'erent isotopi ompositionD one di'erentites etween isoE topomers nd isotopologuesF ssotopomers hve the sme numer of eh isotopi tom ut di'er in their positionF he term is ontrtion of 9isotopi isomer9 PRF ssotopologues re moleulr entities tht di'er only in isotopi omposition @numer of isotopi sustitutionsA PRD eFgF r 2 16 yD rh 16 yD r 2 18 y nd r 2 17 yF

δ A/r = R A R r -1 (×10 3 ) @IFUA
sn the se of wterD the stndrds used s interntionl referenesD re ienn tndrd wen yen ter @wyA nd tndrd vight entrti reipittion @veA PTF he solute isotope rtios for wy hve een determined toX il retion or phse trnsitionF es n exmpleD during evportion of wterD the most undnt nd light isotopologue r 16 2 y preferentilly evportesD resulting in isotope rtios tht re lower in the vpor phse ompred to tht in the liquid soure wterF he di'erene in the isotopi omposition of two ompounds in equilirium @A ⇔ BA or eE fore nd fter physil or hemil trnsition @A → BA n e desried with the isotope frtiontion ftorD whih is de(ned sX

α A (B) = α B/A = R B R A @IFWA
es the hnge of the isotope rtios is often very smll @α ≈ 1AD one often uses the frtiontion instedD whih is de(ned s = α B A -1 @normlly reported in permilAF sn generlD we distinguish etween two kinds of frtiontionD equilirium frtiontion nd kineti frtiontionF iquilirium frtiontion desries the di'erene in isotope rtios etween two sttes tht re in therml equiliriumD iFeF in system with no net )uxesF st n e shown QPD QQ tht the frtiontion ftors of two moleules n e relted to the rtio of the respetive prtition funtionsD detiled disussion is however eyond the sope of this workF sn the se of wterD the equilirium frtiontion ftors re only dependent on temperture nd not on pressureF por the phse hnge ie to vporD the most ommonly used eqution for δ 2 r ws determined y werlivt QR in IWTU nd is vlid for -40 °g ≤ T ≤ 0 °gX

ln α ice-vapor ( 2 H/ 1 H) = -9.45 • 10 -2 + 16289 2 @IFIHA
with in uelvinF por the phse hnge etween liquid nd gs phse wter for δ 2 rD nd for oth phse hngesD ieEvpor nd liquidEvpor for δ 18 yD the generlly used equtions were

α kin = R w R e = α dif f α eq (1 -h) 1 -α eq h(R v /R w ) @IFIRA
with α eq the equilirium frtiontion ftorD h the reltive humidityD R v the isotope rtio of the vporD R w the isotope rtio of the liquid nd α dif f the di'usion frtiontion ftor ounting for di'erenes in the di'usivities of the di'erent isotopologuesD with eFgF α 18O dif f X

α 18 dif f = D H 2 16 O D H 2 18 O n with D H 2 16 O nd D H 2 18
O the moleulr di'usivity of r 2 16 y nd r 2 18 yD respetivelyF he exponent n depends on the rtio of turulent to moelulr di'usion nd is one if for no turuE lenesF sn the se of ie rystl formtion in loudsD supersturtion n often e enounteredD whih lso results in nonEequilirium onditions with kineti frtiontion @fF lso hpter VAF touzel nd werlivt QW ttriute this to the ft tht the rystlliztion is di'usion limitedD whih mens tht rystlliztion ours reltively fst ut new wter moleules hve to e reEsupplied to the rystlliztion zone y di'usionD whih mens tht the rystlliztion zone is more deE pleted in the hevier rh 16 yD r 2 18 y nd r 2 17 y moleulesD whih ondense resultingly more slowlyF es onsequeneD the vpor eomes more enrihed in the hevier isotopologues omE pred to the equilirium seF he e'etive frtiontion in this se n e desried s QWX

α k = S α e D/D (S -1) + 1 @IFISA
with S the sturtion prmeter @eqution @IFQAA nd D/D the rtio of the di'usion oe0ient of the undnt isotopologue over tht of the rre wter isotopologueF fsed on RHD this leds to

α k (δ 2 H) ≈ S 1.0251α e (S -1) + 1 @IFITA α k (δ 18 O) ≈ S 1.0285α e (S -1) + 1 @IFIUA @IFIVA
elterntivelyD the kineti frtiontion in this se n e desried with QWX

α kin = α eq α dif f (S -1) + 1 S @IFIWA
with the de(nition of the prmeters s oveF his eqution lerly shows the e'et of the supersturtion nd the di'usivities of the di'erent isotopologues on the reltion of kineti nd equilirium frtiontionF prtiontion tht ours in n open system with n immedite removl of evported wterD is desried y the soElled yleigh frtiontionF st is generlly enountered when dry gs

)ux removes the wter vpor from the evportion zoneF feuse of the ontinuous removl of lrger frtion of lighter isotopologuesD the δ vlue of the remining liquid eomes inresE ingly enrihed nd onsequently the δ vlue of the vporF he priniple of this frtiontion is demonstrted in (gure IFID whih is sed on similr (gure from PSF vet N e the numer of the most undnt isotopi moleulesD whih is pproximtely equl to the totl numer of moleuesD nd R the isotope rtio of rre to undnt isotopologueF he numer of the rre isotopi moleule is thus N rare = R • N F et eh time stepD -dN moleules re evported from the liquid volumeF sf we neglet the the numer of other rre isotopi moleulesD whih is true to good pproximtionD we n write the mss lne of the rre isotopologue sX

R 1 + R N = R + dR 1 + R + dR (N + dN ) - α eq R 1 + αR dN @IFPHA
feuse of the smll undne of the rre isotopologueD we n pproximte the totl numE er of moleules with the numer of the most undnt isotopi moleuleF e thus equl ll denomintors with 1 + RF iqution IFPH then eomes

RN = (R + dR)(N + dN ) -αRdN @IFPIA
sf we now neglet the produt of the di'erentilsD dRdN ≈ 0D we n seprte the two vriles nd integrte the eqution with the oundry ondition

R = R 0 for N = N 0 F his leds to R R 0 = N N 0 α-1 @IFPPA
1.2. Isotopes W with R 0 the originl isotopi omposition of the liquid nd N 0 the initil totl numer of moleules in the liquidF sn (gure IFPD the inresing enrihment of the liquid due to ontinuous removl of isotopilly lighter wter vpor is shown for typil se for δ 2 rF pigure IFIX hemtis of the yleigh proessD with N the numer of the most undnt isotopi moleuleD R the isotope rtio of the liquid nd α the frtiontion ftor etween liquid nd vpor phseF pigure IFPX huring the evportion proessD the liquid eomes inresingly enrihed in the hevier isotopes s lighter isotopes evporte preferentilly nd the isotope rtio inreses @lk lineAF gonsequentlyD the verge isotope rtio of the frtion tht ws lredy evported @in redAD inreses until it logilly mthes the initil isotope rtio of the liquid when ll wter is evportedF hese di'erent frtiontion proesses give (rst ideD how nturl ouring trnsitions ehve nd n e desried mthemtillyF yf ourse more omplex frtiontion proesses n ourD with omposition of the di'erent frtiontion mehnisms desried ove or with dditionl soures nd sinks of wter vporD requiring more intrite nd detiled modelsF vpor isotopesD the mesurement n not e done diretly on the wter moleulesD ut hs to e preeded y hemil trnsfer of the isotope in question to moleule tht n e nE lyzed diretlyF sn the se of 18 yD the trnsfer is typilly done etween r 2 y nd gy 2 in n equilirium proess involving the ironte retionD whih normlly requires severl hours to reh equilirium SQF en urte mesurement of 17 y in r 2 y y the gy 2 equilirtion method is prtilly impossile euse 17 y 12 g 16 y ppers in the sme mss hnnel s the more undnt 16 y 13 g 16 yF eurte mesurements of 17 y nd 18 y n e mde following the method of frkn nd vuzRRF snsted of gy 2 D gop 3 is used s regent to )uorinte wter smples enling the determintion of δ 18 yD s well s δ 17 yD y sw on y 2 F sn the se of 2 rD di'erent methods existD inluding the redution to hydrogen gs t n elevted temperture with suitle reduing gent SR!ST nd onEline pyrolysis of wter in omintion with ontinuousE)ow sw SUD SVF wost of these tehniques require very urte temperture regultion nd reltively lrge smE ple quntities @typilly RES mvASQD whih re not lwys villeF sn dditionD the hemil trnsfer is usully very time onsuming nd thus mkes relEtime nlysis prtilly impossileF woreoverD sine the 18 y nd 2 r isotopi rtio determintions re not rried out simultneously on the sme smpleD one risks to introdue unorrelted errors in the two mesurementsF sn the se of wter vpor isotope mesurementsD n dditionl drwk of sw is tht the vpor (rst hs to e olleted in the form of liquid wter or ieD whih n for exmple e done vi ryogeni trppingSW or with moleulr sieve THF roweverD prt from the risk to hnge the isotope rtios during the trpping or reovery of the wterD this lso seriously limits the temporl resolution nd renders monitoring of fst isotope hnges virtully impossileF

(ν -ν 0 )X σ = Sg(ν -ν 0 ) @PFQA 2.2.
α(ν) l = S g(ν -ν 0 ) n l @PFRA
he line pro(le funtion g(ν -ν 0 ) depends on pressure nd temperture nd is normlizedX ∞ -∞ g(ν)dν = 1F he line strength S of the sorption trnsition is n importnt spetrosopi property of the soring speiesF S depends on the trnsition dipole momentD whih is purely moleulr propertyD nd on the numer of moleules in the lower level of the trnsitionD whih n e desried y the foltzmnn distriutionF st is thus lso dependent on the tempertureD whih strongly in)uenes the popultion distriution over the rottionl levels of the ground virtionl stteF por given trnsitionD the temperture dependene n e desried y the following eqution TPX

S(T ) = S(T 0 ) • Q(T 0 ) Q(T ) • e E kT e E kT 0 • 1 -e -E -E kT 1 -e -E -E kT
I rd = I 0 exp ct l (-ln R + α) @PFWA
he dey time onstnt @ringEdown timeA n e written sX

τ = 1 c(-ln R + αl) @PFIHA
hen n sorer is present in the mesurement ellD the dey rte of the light intensity is inresed nd the ringEdown time deresesF he mesurement of the ringEdown n e onverted into n sorption oe0ient y sutrting the ringEdown rte of the empty vity from the ringEdown rte of the vity with n soring smpleX

α = 1 c 1 τ - 1 τ 0 @PFIIA
where τ 0 is the ringEdown time for the empty vityF en importnt mesure of the performne of n optil spetrometer is the minimum sorptionD whih n e mesuredF sn gh instrumentsD this is determined withX

α min = 1 c 1 τ 0 -∆t min - 1 τ 0 ≈ ∆τ min cτ 2 0 @PFIPA
with ∆τ min the minimum mesurle di'erene etween τ nd τ 0 F es inditor of the sorption mesuring performne of n instrumentD one generlly sttes the xoiseEiquivlent esorption @xieA UQD whih is the minimum detetle sorption oe0ient

tht n e distinguished from empty vity losses during one seond mesurement intervl with I sigm unertintyD per squre root of the dtEquisition rte f X

N EA = 1 f 1/2 ∆τ min cτ 2 0 @PFIQA
sn the se where white noise domintes the mesurement sttistisD whih is generlly the se for short quisition timesD the noise dereses with the inverse squre root of timeF his is the reson for the dependeny on the squre root of the dtEquisition rte in eqution @PFIQAF sn ddition to the ehvior of the intensity with timeD we lso hve to onsider the reltion of intensity nd frequeny enountered in optil spetrometersF sn vity with two mirrors with sme re)etivity RD the intensity of the trnsmitted rdition n e lulted with the eiry formulD when exittion of other trnsverse modes thn iw 00 is ignored @see eFgF URAX

I T (ν) = I 0 (ν) (1 -R) 2 (1 -R) 2 + 4R sin 2 (Φ/2) @PFIRA
with ν the input frequeny of the rdition nd Φ the phse di'erene etween two suessively re)eted prtil wves inside the vityD whih is Φ = 4lπν c F he eiry formuls re lulted y tking the wveElike nture of light into ount nd interferenes re onsidered s given light wve propgtes k nd forth inside of vityF he trnsmitted intensity is mximum when the denomintor of eqution @PFIRA is minimumD whih is the se when the sine is zeroF his is the se for

2π c lν = mπ @PFISA nd ν m = m c 2l = m∆ν l @PFITA
∆ν l is the frequeny intervl etween two resonnes nd is lled pree petrl nge @pAF st depends on the distne l etween the mirrorsF IW feuse of this ehviorD n optil vity works s (lter with mxim only for frequeniesD whih ful(ll the ondition from eqution @PFITAF por eh frequeny tht follows eqution @PFITAD the length of round trip of the light in the vity orresponds to multiple of the wvelengthD orresponding to longitudinl mode of the optil vityF his reltion ensures onstrutive interferene of re)eted light wve when it overlps with itself fter full round trip in the vityF eprt from these longitudinl modes with nodes only in xil diretionD there re lso modes with nodes in xE nd yEdimension @in grtesin oordintesA nd rdil dimension @ylindril oordintesAD respetivelyF he olletivity of modes is lled rnsverse iletromgneti wodes @T EM mnq A D with susripts mD nD nd q for the numer of nodes in the respetive dimensions @q is the longitudinl numer of modes nd often omittedAF en exmple of di'erent iEmodes is shown in (gure PFQF pigure PFQX hemti representtion of the eletri (eld distriution for the vertil polriztion se in the xyEplne in the resontor in ylindril oordintesD (gure from URA he pull idth rlf wximum @prwA of the resonne given in eqution @PFIRAD is UIX

∆ν c = c 2πl 1 -R √ R @PFIUA
he width of vity mode thus depends on the mirror re)etivity nd on the vity length lF he rtio of the p nd the width of vity mode is de(ned s the pinesse F X

F = ∆ν F SR ∆ν c = π √ R 1 -R @PFIVA
xote tht this formultion is true for linerD ut not Eshped vityD where the eqution hs to e modi(edF st is n inditor of how well seprted nd nrrow the vity modes reF e grph showing the trnsmittne for di'erent re)etivities R @sed on (gure from URA is shown in (gure PFRF ith inresing re)etivityD the vity modes eome inresingly nrrowF snsted of mesurements of the ringEdown time for the determintion of the sorption oe0E ientsD it is lso possile to onsider stedy stte onditions with ontinuous light injetionF his leds to gvity inhned esorption petrosopy @gieA tehniquesF PH 2. Measurement of isotopes pigure PFRX he vity trnsmittne @eqution @PFIRAA for re)etivities of R = 0.1D 0.5 nd 0.83F et higher re)etivities @orresponding to higher pinesseAD the prw eomes smller nd the individul vity modes re muh etter seprted @(gure sed on similr (gure from URA 2. Measurement of isotopes mirror t the pex of the vity @leled M a A is sent k to the lser nd ensures tht only light re)eted t mirror M 1 inside the vity returns s optil feedk @ypA to the lserF e phoE todetetor @hA with emsplitter @fA is used to monitor the injeted lser intensityD wheres signl detetor ehind the vity mesures the vity outputF en ttenutor @eAD eFgF linE er polrizerD etween the vity nd the lser is used to djust the level of feedk to the lserF es the lser is snned over frequeny rngeD it is slowed down due to the optil feedk nd stys longer t the suessive vity frequenies @fF (gure PFTAF et higher feedk levelsD the lser ouples stronger to the vity frequenies nd the resident time for eh frequeny is extendedF pigure PFTX pigure from VPF prequeny of the diode lser oupled y optil feedk to the Eshped vityD s funtion of free running lser frequenyD during the pssge through vity mode for two di'erent levels of feedk @solid nd dotted lines for wek nd strong feedk levelsD respetivelyAF he liner dshed line indites the free running lser frequenyD whih is diretly proportionl to the lser urrentF errows in the plot indite the pth of the oupled lser frequeny @α → β → γ → δ when the lser urrent is tuned nd emphsize the longer residene time t the respetive vity frequeny he distne etween the lser nd the vity equls L 2 D the length of the seond vity rmF his ensures tht onstrutive interferene inside the lser vity is otined for ll vity modesD s the distne orresponds to n integer multiple of oneEhlf the wvelength irrespetive of the ext wvelength vlue @ detiled derivtion n e found in VIAF o ompenste for instilities in the lserEvity distne nd vity length due to temperture nd mehnil vritions or disturnesD mirror etween lser nd vity is mounted on piezo elementD ontrolled y feedk loopF he error signl for the feedk loop is otined y nlysis of the symmetry of the trnsmission pro(les of the vity modesF por the on(gurtion desried here ove nd used in our spetrometerD in whih the lser to vity distne equls L 2 D modes for whih the vity round trip is n even or odd multiple of oneEhlf of the wvelength @from now on simply lled even nd odd modesAD experiene 2.5. Optical feedback cavity enhanced absorption spectroscopy (OF-CEAS) PS slightly di'erent re)etion oe0ient t the folding mirrorD whih results in smll di'erene in the ringEdown time ssoited with the odd nd even modes VID VPF roweverD this di'erene n esily e orreted for in the dt nlysisD s the di'erene remins onstnt over the smll tuning rnge of the lser wvelengthF en ypEgie spetrum is (nlly reorded y determining the mxim of suessive T EM 0,0 vity mode pro(les in the rw ypEgie signl @fF (gure PFUA nd normlizing them with the signl of the referene detetorF et the end of eh lser snD the lser is interrupted for little more thn the durtion of one vity mode to mesure ringEdown on one vity modeF hese h mesurements re used to lirte the trnsmission signl nd to onvert the spetr to sorption unitsD sed on the @pproximtedA reltionX

√ H k τ k = √ H m τ m @PFIWA
τ 0 = L/c 1-R τ 0 = L 1 +L 2 2c(1-R)
ringEdown time with sorer

τ = -L/c 1-R+αL τ = L 1 +L 2 2c(1-R+α(L 1 +L 2 )) pinesse πR 1- √ R πR 1-R 2 mxF trnsmission for lossless vity ≈ 1 (1+ L T ) 2 ≈ 1 4 1 (1+ L T ) 2 H(α → 0, L + T 1)
le PFIX pD ringEdown timeD pinesse nd mximl trnsmission for liner nd Eshped vity s funtion of re)etivity RD trnsmittne TD nd the length of the vity rm@sA L @liner vityAD nd L 1 nd L 2 @Eshped vityAD respetivelyF c is the speed of lightF

H max (α m ) = T exp(-α m l 1 /2) 1 -R 2 exp(-α m (l 1 + l 2 )) 2 @PFPHA he e'etive mirror trnsmission nd re)etivity oe0ients T nd R re T = (T a T 1 ) 1/2 nd R = (R a ) 1/2 (R 1 R 2 ) 1/4
with the susript a inditing the folding @pexA mirror nd 1 nd 2 the mirrors t the end of the two vity rms @the trnsmitted intensity is lulted for mirror IAF 2.6. Absorption scale linearity PU sn generlD ll three mirrors re from the sme th nd re virtully identilF es the ngle etween the two vity rms is very smllD the re)etivity is prtilly the sme s for norml inidene nd the re)etion nd trnsmission oe0ients n e onsidered equl for the three mirrorsF iqution PFPH is vlid for vity injetions y perfetly monohromti (eld slowly pssing through resonneF his is generlly true in the se of ypEgieD s the lser tuning is su0iently slow to ssure full vity uildup during frequeny loking y optil feedkD whih lso results in lser line width nrrowing to well elow the vity mode widthF feuse of onservtion of energyD the e'etive mirror losses due to sorption nd sttering re given y L = 1 -R -TF ith thisD it is esy to show with eqution PFPH tht the mximum trnsmission for ompletely lossless vity @α = 0 nd L = 0A rehes PS7X

H(α ← 0D L + T 1) ≈ 1 4 1 (1 + L T ) 2 @PFPIA
iqution PFPH is derived y squring the sum of the mplitudes of the (eld trnsmitted through the mirror t the end of one vity rm nd not y summing the squre of the mplitudes VPF he summtion of the intensities would not ount for the resonne e'et in ypEgie nd is only vlid in the se of rodnd inoherent soureF his would result in sustntilly lower trnsmission of only T/4F

sf we pproximte exp(-α m l 1 ) ≈ 1 in the numertorD it is possile to invert eqution PFPHD following the derivtion presented in T nd VIX

α m = 1 l 1 + l 2 2 ln(R) -ln 1 - T √ H max @PFPPA
e further mke the ssumption T/ √ H max 1D whih is in generl true s T is typilly smller thn IHH ppm nd very lrge sorptions re voidedD suh tht H max > 17F ith thisD we n write

α k ≈ 2 l 1 + l 2 ln(R) + T (l 1 + l 2 ) H max (k) @PFPQA
sf we write ln(R) ≈ 1 -R = T + LD it eomes evident tht the (rst term on the right hnd of eqution @PFPQA is -γ 0 D the loss per unit length for the empty vityF e n thn writeX

γ k c = α k - 2 l 1 + l 2 ln(R) = α k + γ 0 c ≈ T (l 1 + l 2 ) H max (k) @PFPRA

System control and house keeping

e lrge improvement hs een mde in the temperture stility of the system ompred to previous versionsF heres ss ws stilized to 35.5 ± 0.5°g y n onGo' regultionD the temperture of the instrument is now regulted in two step system to 45°g with muEpreision nd drift of less thn HFS mu over PHH min @see (gure QFIAFF he ir temperture in the entire instrument is regulted to 38 ± 0.1 °g with sh regulted ig @uperoolA in omintion with two mixing fnsF purthermoreD the temperture of the optil tringle is stilized t 45 °g with dditionl heting nds D whih re regulted with sh loop vi pulse width modultion @wAF he temperture sensor used for the regultion is very low drift tIHHHD whih is red out with IT it resolutionF o void dditionl eletroni het in the insulted ox due to the power supplyD the instrument is powered y ommerilly ville PPH single output desktop power supplyF feuse of two dditionl tIHHH temperture sensors tht re freely suspended in the inlet nd outlet strem of the vityD it is lso possile to orret mesurements for )ututions of the gs tempertureF his eomes espeilly importnt if tmospheri mesurements with lrge vritions of the ir temperture @eFgF dyEnight yleA shll e doneF hue to the di'erent temperture dependeny of the single sorption linesD this n eome ruil when isotope rtios should e determined with high uryF he pressure in the vity is stle within the miror level @etter thn region @(gure QFPAD this region is suited for mesurements of ll of the four isotopologues r 16 2 yD rh 16 yD r 2 18 y nd r 2 17 yF feuse of reltively lrge numer of dditionl wek sorption pigure QFPX imulted spetrum t UIVRm -1 D I ppmv r 2 16 yD spetrl informtion from the ritrn dtse TI 3.6. Choice of spectral ranges QQ lines nd severl methne sorption lines in this spetrl regionD the nlysis of the spetrl dt is more di0ult thn in other spetrl regionsF en lterntiveD for mesurements in whih r 2 17 y is of no or little interestD is the spetrl reE gion round UPHH m -1 in whih the sorption lines of the three isotopologues r 16 2 yD rh 16 y nd r 2 18 y re etter seprted @(gure QFQAF his regionD whih we used for some of our meE surementsD is lso the region of hoie of the most ommon version of the instruments of vos qtos eserh snF UVF por mesurements t very low wter onentrtions @`RH ppmvAD pigure QFQX imultion of spetrum t UPHHm -1 nd I ppmv r 2 16 yY spetrl informtion from the ritrn dtse TI we hose n lterntive spetrl region round UPVT m -1 @fF (gure QFSAD whih inludes n r 2 18 y sorption line tht is nerly ftor R stronger nd n r 16 2 y line tht is more thn ftor SH stronger thn in the ove mentioned regionsF sn dditionD the region round UPVT m -1 enles the mesurement of δ 2 r with spetrl lines of r 2 16 y nd rh 16 y t UPVH m -1 F ith the ville lser @xnoplus qmrAD the two region ould e rehed y seleting the pproprite temperture of the lser hipF sn tle QFID the wvenumerD intensity nd temE perture dependene of the line strength for the prinipl sorption lines TI is shown for the di'erent spetrl regions used in our mesurementsF por the spetrl region round UPVT m -1 D the hnge of the wvelength region dditionlly results in n inrese of the ringEdown time of the instrument due to higher re)etivity of the vity mirrors @fF (gure QFRAF ith ringEdown times of up to IVH µsD this on(gurtion results in signi(ntly inresed sensitivity in the low wter vpor onentrtion rnge @see hpter VAF his spetrl rnge ws not used in our instrument ut we dpted di'erent ypEgie speE trometer tht ws initilly uilt in our lortory y tF rig of the urlsruhe snstitute of ehnology VUF pigure QFRX he re)etivity of our vity mirrors vsF the wvenumer @mesurements y F ussiD vshyD tpAF he re)etivity is higher for the region UPVT m -1 proposed for mesurements of δ 18 y t very low wter onentrtions ompred to the spetrl regions used eforeF isotopologue wvenumer intensity temperture dependene

[m -1 ] [m -1 /(moleule × m -2 )] 7G°g
I(ν) = I 0 exp - 2 ln(2)(ν -ν 0 ) γ D @RFIA
with γ D the prw of the qussin funtionX

γ D = ν 0 c (8k B T ln(2)/m) 1/2 @RFPA
with ν 0 the enter frequeny of the sorption in rzD c the speed of lightD k B foltzmnn9s onE stntD T the temperture in uelvin nd m the mss of the moleule in kgF et higher pressuresD the ollision etween moleules in the gs n led to redution of the lifetime of the moleule9s upper energy stteD whih ording to reisenerg9s unertinty prinE iple leds to n inresed linewidthF he line shpe in this se is desried y vorentzin funtion VWX

I(ν) = I 0 2πγ C (ν -ν 0 ) 2 + (πγ C ) 2 @RFQA @RFRA
with γ C the prw of the vorentz funtionF et higher pressures @p ≥ 1000 mrAD the ollisionl rodening is the dominnt mehnism nd the pro(le n e desried reltively well y purely vorentzin line shpe WHF et intermedite pressure @0.5 mr ≤ p ≤ 1000 mrAD the line shpe is often pproximted with the oigt pro(leD whih is onvolution of qussin QV 4. Data analysis procedures nd vorentzin pro(leF he normlized oigt pro(le n e written s WIX

Γ V (ν) = γ C π 3/2 γ 2 D +∞ -∞ e -y 2 ν-ν0 γ D -y 2 + γ C γ D 2 dy @RFSA nd hs in (rst pproximtion prw γ V of WPX γ V ≈ 0.5346γ C + 0.2166γ 2 C + γ 2 D @RFTA
roweverD the oigt pro(le is only n pproximtionD s it does not tke into ount further mehnisms tht in)uene the line shpe of spetrl linesF sn relityD the hoppler pro(le of the spetrl lines is nrrowed euse of ollisions etween the tive moleules nd moleules in the u'er gsD whih result in redued free pth length @to elow the wvelength of the infrred rditionA nd onsequently in smller veloity of the moleulesF wo di'erent models hve een developed to tke this nrrowingD the soElled hike e'etD into ountF he utin nd oel9mn model @in the following utin pro(leAWQ nd the model of qltry @qltry pro(leAWRF hese two models tke into ount the hoppler rodeningD the hike nrrowing nd the ollisionl rodeningF heres the qltry model ssumes tht the mss of the tive moleule is muh hevier thn the mss of the moleules of the rrier gs @nd onsequently mny ollisions re required to indue notle veloity hngeAD the model of utin nd oel9mn supposes the ontrryD nmely tht the perturer is muh hevier thn the tive moleule @nd single ollision su0esA WHD WQD WRF es in our seD the tive moleule is in generl lighter thn the rrier gs moleulesD we will fous here on the utin pro(leF his pro(le n e expressed s WHX

γ R (γ D , γ C , z) = 1 γ D √ π W (γ D , γ C + z) 1 - √ πzW (γ D , γ C + z) @RFUA with W (γ D , γ C , z) = i π ∞ -∞ e -t 2 ( ν-ν0 γ D + i( γ C γ D + z) -t √ ln(2)
) dt @RFVA nd the nrrowing prmeter zX

z = β C γ D @RFWA
with β C the oe0ient of ollisionl nrrowing @given in cm -1 AF 4.1. Analysis of experimental spectra σ@ 2 rA σ@ 2 rA σ@ 18 yA σ@ 18 yA σ@ 17 yA σ@ 17 yA r 2 y @R sA @T opt A @R sA @T opt A @R sA @T opt A ppmv

σ avg = σ 0 • 1 √ N
heres the simulted dt follows the 1/ √ N ehviorD the residul of the (t to the experimenE tl dt lerly does not tend towrds zeroD ut insted levels o' t vlue of out 6 • 10 -11 m -1 @(gure RFTAF glerlyD lrge frtion of the noise is not suseptile to vergingF sndeedD if we ompre the (t residul of single spetrum with tht of the (t to the verge of (ve or twenty spetr @(gure RFUAD we see tht the struture of the residul remins very similrD independent of the numer of verged spetrF his mens tht lrge frtion of the noise in our mesurements is not fst hnging white noise ut slowly vrying strutured noiseD possily used y multipleD wek optil fringes WVF vrger fringes re typilly used y prsiti re)etions of the lser em nd n e efE (iently redued y thing these re)etions with optil trps or improvements in the optil lignmentD whih ws e0iently done in our setEupF mller fringesD eFgF due to ksttering on the optil surfes in the em pthD re primrily due to sttering of light on the optil elements in the em pth nd re virtully impossile to remove WWF his strutured noise

(a) (b) (c)
pigure RFRX ellnEerle plot of mesurement t VHppmv ompred to simulted mesureE ment t the sme wter onentrtion for A δ 2 r A δ 18 y nd A δ 17 yF fothD simulted nd experimentl spetr hve w devition of 7 × 10 -11 m -1 Gs on the (tF pigure RFSX e histogrm over the residuls of QH susequent spetr shows tht the noise is following qussin distriution @in lkA RS pigure RFTX he residul of the spetrl (t vsF the numer of spetr verged @in lkAF sn redD the ehvior for rndom white noise is depitedF hen verging over severl spetrD the residul of the (t does dereses muh slower thn for rndom white noiseF pigure RFUX gomprison of the (t residul without verging @seond pnelD in lkAD with the residuls of (t to spetrum verged over S @third pnelD in lueA nd PH individul speE trD respetively @ottom pnelD in redAF he shpe of the residul remins nerly unhngedD independently of the numer of vergesF he noise pttern is thus not rndom white noise ut systemti timeEinvrint noiseF is highly orrelted etween susequent spetr nd results in smller vrition of the (t on short time sle thn the fst hnging white noiseF feuse of thisD the ellnEerle plot for the experimentl dt strts t muh lower vlues thn the orresponding plot for syntheti dt with the sme level of @fst hnging whiteA noiseF o tke the more stle noise soure in the genertion of syntheti spetr into ountD n dditionl qussin distriuted noise is dded one to the seline of the syntheti spetr nd kept onstnt throughout the entire simultionF fy hnging the reltive mount of the strutured noise to the entire noise levelD it is thus possile to dpt the simultion to the mesurements nd to estimte the ontriution nd in)uene of strutured noise on the rel mesurementsF ith n inresing ontriution of timeEinvrint noise to the totl noise of the simultionD the stndrd devition of the delt vlues dereses nd n e mthed to the rel mesurementF ith n w of the strutured noise tht is IFS times the w of the fst hnging white noiseD the simulted ellnEerle plot is in very good greement with the experimentl dt @fF (gure RFVAF yf ourseD for longer integrtion timesD the syntheti elln devition ontinues to dereseD wheres the preision of the rel mesurement is limited y instrumentl drift nd inreses ginF he w of timeEinvrint noise ws set to 6 × 10 -11 m -1 nd the w of vrile noise to 4 × 10 -11 m -1 F por the summtion of these two independent noise distriuE tionsD the qudrture of the two soures hs to e ddedD resulting in n overll w of the

residul of σ tot = √ 6 2 + 4 2 m -1 = 7.2 m -1 nd ontriution of the strutured noise to the overll noiseD whih is 6 m -1 /7.2 m -1 ≈ 837F
sn (gure RFWD the w of the residul versus the numer of verged residuls is shown just s in (gure RFTD ut this time inluding the orresponding ehvior for the syntheti dt with VQ7 strutured noiseF he w of the simultion with strutured noise is slightly lrger thn for the experimentl dt ut perfetly reprodues the ehvior for di'erent vergingF feuse of the lrge ontriution of slowly hnging strutured noise in the mesurementsD the )ututions etween susequent spetr is smller thn would e expeted from the residul on the (tsF sn ftD the @shortA time preision tht n e hieved in the mesurements would e equl to the preision of mesurements with the white noise omponent onlyF he strutured noiseD whih remins virtully onstntD permnently ises the model (t to the spetrum nd is therefore re)eted in the ury of the mesurement nd not the preisionF pigure RFVX he ellnEerle plot of (gure RFR now inluding the devition for simultion with TH7 strutured noise nd the sme overll noise levelF heres the simultion with rndom white noise only shows muh lrger devitions thn the experimentD the simultion with TH7 strutured noise perfetly mthes the experimentl dtF pigure RFWX he residul of the spetrl (t vsF the numer of spetr verged @in lkAF sn redD the ehvior for rndom white noise is depitedF hen verging over severl spetrD the residul of the (t does dereses muh slower thn for rndom white noiseF yne possiility to hek for nonElinerity of the photo detetors is to mesure onstnt smple with the spetrometer nd hnge only the lser powerF sf the detetors show nonE liner ehviorD this would result in hnge of the mesured onentrtionsD sine the seline of the mesurement @orresponding to high detetor signlA nd the peks of the sorption lines @orresponding to low detetor signlAD would e 'eted di'erently y the hnge of the lser powerD provided tht the sorption is reltively strongF sn dditionD the referene hnnel my e 'eted euse of the hnge in lser power with detuning of the lserF sn our seD howeverD this hnge is pproximtely PH7 over the spn of one spetrumD wheres the sorption depth of the stronger line@sA in the spetrum n e well over SH7D depending of ourse on the wter onentrtionF roweverD hnge of the lser power in our instrument

n not e done y omputer nd would require to open the instrument to mke the neessry hnges to the lser urrent driverF his would lso led to perturtion of the instrument stilityD in prtiulr of the temperture stiliztionD whih ould in its turn introdue hnges or instilities in the mesurementsF feuse of this we exmined possile nonElinerity of the detetors on severl ringEdown eventsD whih re performed t the end of eh lser sn to sle the sorption spetr @see lso hpter QAF hen the lser is interrupted t the end of snD the light intensity normlly deys exponentillyFF his ringdown event is rried out in spetrl region with little or no gs sorption in order to void possile line sturtion e'ets @see prgrph RFSA nd euse in this se the ringdown time is longD nd n thus e mesured more urtelyF xowD if the output voltge of the photo detetors hs nonEliner omponentD the mesured dey will not e purely exponentilF he dependeny of the signl voltge of the detetors on the inident light intensity inluding 4.5. Power saturation RW nonEliner omponent n e desried y the following reltionX

V (t) = V 0 + I(t) + I(t) 2 ith I(t) = I 0 + A exp t-t0 τ this leds toX V (t) = V 0 + I 0 + I 2 0 + A(1 + 2 I 0 ) exp - t -t 0 τ + exp - 2(t -t 0 ) τ = V 0 + A exp - t -t 0 τ + exp - 2(t -t 0 ) τ @RFIHA
I s = ch 3 Γ 2 k 3 A @RFIIA
with cX speed of lightD hX lnk onstntD AX the iinstein oe0ient of the trnsitionD kX the wve vetor nd Γ the full width t hlf mximum @prwA of trnsitionD whih tkes in the oigt pro(le lso into ount the e'et of ollisionl relxtionF he dependene of the sturtion intensity on the pressure in the gs ell is tken into ount vi the prw of the sorption lineD whih is lrger for higher pressure nd pprohes the hoppler prw for very low pressuresF o investigte if sturtion of one or severl sorption lines ours in our instrumentD we nlyze ringEdown events mesured t the entrl frequeny of the sorption lines of the investigted wvelength regionF es oserved y omnini et lF IHR nd qiusfredi et lF IHQD ringEdown is no longer single exponentilD when sturtion of trnsition ours s the degree of sturtion diminishes with diminishing intrEvity intensity nd the intensity ultimtely eomes smller thn the sturtion intensity of eqution @RFIIAF he iinstein oe0ients of the trnsitions investigted in our ypEgie spetrometer re shown in tle RFPF es lrger iinstein oe0ient orresponds to lower sturtion intensity @eqution @RFIIAAD the sorption line of r 18 2 y t UIVQFSVSW m -1 D whih hs the lrgest iinstein oe0ientD would e the (rst sorption line 'eted y sturtion e'etsF o estimte if power sturtion ours in our mesurementsD isotopologue wvenumer m 1 iinstein oe0ient s le RFPX iinstein oe0ients of the trnsitions investigted in ss @from TIA we ompre the intrvity intensity I c with the sturtion intensity @eqution @RFIIAAF he intrvity intensity n e lulted with

I c = ( F π • I 0 ) • η @RFIPA
with F the vity (nesseD I 0 the intensity of the injeted light nd η the portion of I 0 injeted into the T EM 00 modesF he intensity of the lser is in our se pproxF 2 • 10 -3 Gm -2 nd the injetion e0ieny into the T EM 00 modes round PH7F ith (nesse of PVVDHHH @fF setion QFIAD this leds to I c = 1.833 • 10 6 kgGs 3 F por the sturtion intensity @eqution @RFIIAAD we need to know the prw of the trnsitionD SP 4. Data analysis procedures whih we n otin from our (t model to the experimentl dtF por the r 2 18 y sorption t k = 7183.58578 m -1 D the qussin prw is TIS wrz nd the vorentzin prw pproxF WV wrzF e pproximte the prw with the qussin linewidthD thus underestimting the stE urtion intensityF ith this nd the iinstein oe0ient from tle RFPD the sturtion intensity is I s = 8.087 × 10 8 kgGs 3 D whih is more thn ftor RRH lrger thn the intrvity intensityF sn our mesurementsD power sorption n thus e negletedF por n dditionl experimentl veri(tionD we lso investigte if power sturtion ours y looking t ringEdown events performed diretly on n sorption lineF es mentioned oveD power sturtion would result in ringEdown urves tht re no longer single exponentilF nE fortuntelyD it ws not possile to study the sturtion e'ets on this line s no lser for this wvelength region ws ville t the time of these mesurements @nor ould it e purhsed nd delivered fst enoughAF snstedD the sturtion ws investigted on the rh 16 y sorption t 7200.3024 m -1 F his line hs n iinstein oe0ient tht is hlf s lrge s tht of the r 2 18 y lineF roweverD the sorption for this line is more thn ftor IS wekerD whih mens tht the ringEdown time is longer nd n e mesured more preiselyF por the study of sturtion e'etsD the pressure in the vity ws redued to PFU mrF his redues the density of moleules in the vity nd therefore lso the relxtion of exited levE els due to ollision with other moleulesD e'etively lowering the sturtion intensity level @fF eqution @RFIIAAF o determine the ringEdown more preiselyD insted of one single ringEdown mesurementD QH susequent ringEdown events were vergedF he verged mesurement is shown in (gure RFII on logrithmi sle together with single exponentil (tF he (t gives ringEdown time of τ = 141.01 ± 0.1 µs nd hs χ 2 red = 1.3 × 10 -8 F sn the (t residulD lrger devition is visile for the eginning of the ringEdown mesurementD whih ould e n indition of possiE le sturtion e'etsF roweverD this lrger residul is lso visile for ringEdown mesurements performed on the seline @fF (gure RFIHAD where power sturtion n not ourF sn dditionD the lultion of the sturtion intensity for the rh 16 y sorption line for pressure of PFU mr gives I s = 8.627 • 10 8 kgGs 3 nd rtio of sturtion intensity nd intrvity intensity of I s /I c = 470F hereforeD we n onlude tht no sturtion of the trnsitions our in our mesurementsD whih re done t pressure of QS mrD whih further inreses the sturtion intensities for the di'erent trnsitionsF 4.6 Matrix eects eprt from gs pressure nd tempertureD the line pro(les of the spetrl lines lso depend on the u'er gs used in the experimentF es explined oveD the ollisions etween the moleules of interest nd the rrier gs led to pressure rodening of the sorption lineD whih is desried y the vorentzin line widthF roweverD this rodening is not only dependent on pressure ut lso on whih gs is used s rrierD s the intertions re di'erent for di'erent pigure RFIIX e ringEdown mesurement on the sorption line of rh 16 y t UPHHFQHPR m -1 @AD (t with single exponentil dey funtion @A he residul on the (t shows smll devition in the eginning of the ringEdownD whih n lso e found in ringEdown events performed on the seline of the spetrumF he di'erene of the line widths in di'erent rrier gses is due to di'erenes in the relxtion of the exited sttes due to di'erent ollisionl rtesF o estimte the di'erent line widthsD we mke the @simplistiA ssumption tht the di'erent ollisionl widths re only due to di'erenes of the men free pth lengths @wpA for the two mtriesD whih determine the ollisionl rteF he wp n e lulted using the moleulr dimeter IHSX

l = k B T √ 2πd 2 p @RFIQA
with k B foltzmnn9s onstntD T the temperture in uelvinD d the dimeter of the gs moleules in meters nd p the pressure in slsF he wp di'erene is thus determined y the squre of the di'erent moleulr dimetersF he moleulr dimeters of xitrogen nd yxygen re QUH pm nd QSV pmD respetivelyF por the onditions in our experiments @QS mrD RS °gAD this leds to wp lengths of PFHT µm nd PFP µm for x 2 nd y 2 D respetivelyF por syntheti ir with PH7 oxygen nd VH7 nitrogenD the wp is of the sme rtioD whih results in n wp of PFHW µmF he ollisionl rte in the rrier gs nd therefore lso the vorentzin width of the spetrl lines is proportionl to the inverse of the wpF he vorentzin line widths for x 2 should thus e pproxF IFS7 lrger thn for syntheti irF e more detiled study y woretti et lFIHT revels tht for more omplete pitureD other propertiesD like the di'erent rottionl sttes hve to e tken into ount s wellF he uE thors propose tht the di'erent ollisionl rtes re likely due to di'erent qudrupole momentsD whih ply n importnt role in the dipoleEqudrupole intertion ourring during the ollision etween r 2 y nd x 2 or y 2 F por the r 2 18 y line t UIVQFSW m -1 in our spetrumD they report ollisionl rodening oe0ient of PFPT@IA wrzGorr in x 2 D nd of HFWW@RA wrzGorr in y 2 D whih leds to rodening oe0ient of IFWW@PA wrzGorr in syntheti ir nd n pproxF II7 lrger vorentzin line width in x 2 ompred to irF sn (gure RFIPD two spetr from mesurements with lower (nesse instrument of the sme smE ple t r 2 y≈ SWHH ppmvD is shown for mesurements with the two di'erent rrier gsesF es n e seen in the di'erene etween the spetr in syntheti ir nd the spetr in nitrogenD the di'erene etween the two spetr more negtive t the wings of the sorption lines nd positive for the line mxim @most visile for the two strongest linesAF his indites tht the line widths re it lrger for the nitrogen u'er gs thn for syntheti irF sn dditionD the di'erene shows negtive slope nd is more negtive for lrger mode numersF his is due to very strong r 16 2 y sorption lineD whih is in lose proximity to the end of the mesured spetrl region @orresponding to pproxF mode PPHAF feuse of the stronger rodening in nitrogenD the wing of this sorption line lso hs lrger in)uene in nitrogen thn in irF e (t to the sorption lines with (xed qussin line widths nd free vorentzin line width indites vorentzin line widths tht re pproxF RFS7 lrger for x 2 thn for syntheti irD whih is in reltive good greement with the vlue given y woretti et lFIHTD espeilly regrding the ft 4.7. Conclusion SS tht we use utin line pro(leD wheres woretti et lF ssume oigt pro(le of the lineF st is di0ult to estimte the error tht would e mde in the isotope determintionD if di'erE ent rrier gses would e used for lirtion nd mesurement or if prmeter (le with vorentzin widths for nother mtrix is usedF irroneous line widths re prtly ompensted y other prmeters in the spetrl (tD whih mkes simple estimte of the error impossileF sn dditionD we found tht di'erent rrier gses n lso result in hnge of the onentrtion dependene of the isotope rtiosF sn onlusionD the use of di'erent gs mtries should e voided nd if possileD desited smple ir insted of syntheti ir should e used for liE rtionsF hue to mesurements t very low wter onentrtionsD this ws not lwys possile in our mesurementsD s most desints do not permit to dry ir to onentrtions elow IHH ppmvF snstedD we hd to use dry syntheti irF roweverD the error mde euse of di'erent moleulr omposition is in this se negligileF irth9s tmosphere onsists of UVFHV7 x 2 D PHFWS7 y 2 nd HFWU7 tre gses nd wter IHUF he syntheti ir is spei(ed with 20 ± 17 y 2 nd 80 ± 17 x 2 F he line width di'erene euse of di'erenes of the gs mtrix is thus smller thn HFHU7 nd does not result in visile hnges of the residul in our mesurementsF

Conclusion

ith ssD the xie t wter onentrtions elow SHH ppmv is typilly 6•10 -11 m -1 rz -1/2 D n improvement y ftor of lmost U ompred to the previous instrument ssD whih is equl to the rtio of the (nessesF hue to the new temperture regultionD the vity temperture is stilized t RS°g with drift smller thn HFS mu over QFT hF yver the sme timeD the drift in vity pressure is smller thn IH µrF his inresed stility results in optimum integrtion times of up to UH min @for longer integrtion times drift degrdes the preisionAD ompred to longest optimum integrtion times of pproxF S min in ssF sn onlusionD the new instrument hieves similr or etter results in terms of mesurement preision ompred to our previous ypEgie wter isotope spetrometerD s well s ompred to most ommeril wter vpor spetrometers ut t wter onentrtion tht is pproximtely n order of mgnitude lowerF he xie of 5.7×10 -11 m -1 rz -1/2 @or 5.4×10 -12 m -1 rz -1/2 when normlized per spetrl elementA is mong the lowest vlues reported for nerEinfrred gie so frD with the exeption of xsgiEyrw @with its muh smller tuning rngeA nd the lowest for gie with se length elow SH mF he improved stility time n e used to inrese the preision on single mesurement efore drift strts dominting the noiseF st lso enles longer uninterrupted reording efore relirtion needs to e rried out WVF Chapter 5 Data Corrections and Calibration es desried in hpter ID the mesurement of isotope rtios is never mesurement of solute vlues ut lwys done reltive to wellEknown lirtion stndrdsF he reommended proeE dure of the snterntionl etomi inergy egeny @seieA to lirte isotope mesurements is to mesure two isotope stndrds nd mke liner orretion of the mesured isotope delt vlues PTD IHVX pigure SFTX helt vlues verged over eh onentrtion step of the two lirtion meE surements with qRV nd qSH @dt not shownA nd the mesurement of qPP @(gure SFSAF por higher wter onentrtionsD the reltion etween wter onentrtion nd delt vlues is prtilly liner wheres it is strongly nonEliner for lower undnesF he two lirtion mesurements re (t with omintion of hyperol nd line @lk nd red lineAF he ( le SFIX pit prmeters of the funtion on the onentrtion dependene for ll three isotope delts for the stndrds qRV nd qSH prmeters of the funtion re di'erent for the two isotope stndrdsD whih is not surprising s the error tht is mde in the estimtion of the onentrtion of the di'erent isotopes is lrger for weker sorption lines nd thus more pronouned for stronger depleted isotope stndrdsF his is espeilly pronouned for δ 2 rD where the (t on qSH indites muh stronger nonEliner onentrtion dependene thn for qRVF heres the di'erene in the reltive undne etween the two stndrds is smller thn Q7 for r 2 18 y nd smller thn P7 for r 2 17 yD it is lrger thn PR7 for δ 2 r @fF tle eFeFIAF por δ 18 y nd δ 17 yD the di'erene in the (t prmeters is smller thn the unertinty on the prmeters nd one glolly vlid funtion ould e ssumed to orret the onentrtion dependeneF he onentrtion dependene of n unknown smple is determined from the onentrtion dependene determined in the two lirtion mesurementsF e ssume tht the funtion for the smple mesurement n e determined s liner omintion of the prmeters δ 0 D b nd m of the (t funtions determined in the lirtion mesurementsF he reltive ontriution of the two results is determined y the di'erene in the delt vlues of the two stndrds nd the unknown smpleF por the prmeter bD this is for exmpleX le SFQX gorreting funtion for the onentrtion dependene for the smple mesurement @qPPA originting from liner omintion of the funtions from the two lirtion mesureE ments ntion of the lirtion is shown together with the verged isotope mesurements of (gure SFT in (gure SFUF sn light redD the error on the orretion sed on the unertinty of the prmeters is givenF he djustment funtion for the smple mesurement lulted from liner omE intion of the orretion funtions for the two lirtion mesurements grees well with the mesurement t di'erent wter onentrtions of the isotope delts for the smple mesurement of qPPF ith the funtions desriing the onentrtion dependeny of the delt vlues for the two wter stndrds @eqution @SFQA nd tle SFPA nd the smple @tle SFQAD the isotope mesurements n e orreted for vritions of the wter onentrtionsF his orretion is done y sutrting the liner nd hyperoli onentrtion dependene from the mesured delt vluesX setEup ws lso employed in our mesurements @see hpter UAF e very roust system tht hs seen wideEspred use nd onvines euse of its simpliity is the soElled uler QUD SPD IPQ!IPUF e dry nitrogen or ir )ow is guided through lrger volume @typilly severl litersA of liquid wterD often through di'usor to rete smller gs ulesF hile the ules rise through the wter olumnD the gs inside the ule eomes sturted US in wterF he temperture inside the wter ontiner is stilized nd monitoredF feuse of thisD it is possile to lulte the isotope rtios in the wter vporD ssuming equilirium frtiontion during the phse hnge @setion IFPFPDQSD QTAF o vry the wter onentrtionD the sturted gs )ow is susequently omined with vrile dry gs )owF es long s lrge liquid wter volume is usedD the inresing enrihment of the liquid phse is often negligile nd well elow the mesurement preisionF roweverD it lso mens tht lrge mounts of stndrd wter hve to e usedF sn dditionD n dditionl error is introdued euse of the indiret determintion of the isotopi omposition of the vpor phse sed on the ssumption of equiE lirium frtiontionF eprt from lirtion systems developed y individul groupsD there re lso ommeril verE sions villeF he tndrd helivery wodule @hwA in omintion with porizer @irro snFA is sed on two syringe pumps injeting smll ontinuous wter )ow into n evportion hmerD heted to IRH °g UVD IPPD IPVD through whih dry ir strem is guidedF hue to the high temperture in the injetion hmerD wter is evported t the menisus of the needle nd fter short equilirtion timeD the isotope rtio of the vpor phse equls tht of the liquid stndrd wterF feuse of the two syringe pumpsD utomtized lirtions with two stndrds n e performedF enother method is used y the ter por ssotope tndrd oure @sD vos qtos eserhAIIRF sn this devie neulizer spirtes liquid wter from HFS l wter reservoir nd injets smll wter droplets into n evportion hmerD heted to VH °gF pollowing the evportionD the humid ir is mixed with vrile dry ir )owF ith n injetion rte of SHµlGmin r 2 y nd n dditionl dry ir )ow of up to S lGminD onentrtions etween PSHH nd PSDHHH ppm n e hievedIIRF eentlyD qkinis et lF introdued n ultrsoni onentri neulizerD whih hs een used for the isotopi nlysis nd lirtion of ie ores IPWF everl of the ove mentioned lirtion setEups proved to work relily nd generte wter vpor t di'erent onentrtions without frtiontionF roweverD to the est of our knowledgeD no relile nd roust option exists for the lirtion t wter onentrtions elow SHH ppmvF ome of the instruments ould potentilly e dpted to produe lower wter onentrtion y n inrese of the ir )ow through the evportion hmerD or y susequent dilution of the humidi(ed ir strem with dry ir @see lso the lirtion disussion in hpter UAF hisD howE everD results in lrge onsumption of ostly nd often limited stndrd wterD ndGor requires lrge mount of ir dried to level tht is not esily otined in n onEline drying tehnique @eFgFD using hrieriteAF sn dditionD the ir )ow n not e gretly inresed s this would result in turulent )owD whih redues or destroys the stility of the injetionF elsoD with n ir )ow rte of S stndrd liters per minute @slmAD the wter injetion would still need to e lower thn P µlGmin to reh wter mixing rtio lower thn SHH ppmvFF 6.1 Microdrop injector en instrument tht llows the genertion of very low wter onentrtions is the mirodrop genertor IQHD whih ws (rst introdued for wter vpor mesurements y snnone et lF in PHHU IQI nd ws lter lso used y other groups IPHD IPQF ith their mirodrop genertorD snnone et lF IIW were le to generte wter mixing rtios rnging from IP to UTHH ppmv using ommeril piezoEeletri droplet genertor @wirodrop qmrD model whEuEIQHA to generte sunnoliter wter droplets injeted into strem of dry syntheti ir or nitrogenF hue to the smll size of the wter dropletsD evportion is immedite nd no frtiontion oursF he mirodispenser tehnology used for the genertion of mirodroplets is sed on the sme priniple s ommon inkjet printer nozzles IQPD IQQF eround glss pillry with inner dimeter QH µmD piezo ermi tue is mountedF hen voltge pulse is pplied to the piezoeletri omponentD the pillry tue is ontrted nd the liquid inside is ejeted s dropletF por the genertion of dropletD the ontrtion of the glss pillry hs to generte su0ient inerti to overome surfe tension nd visous foresF fy hnging the pulse width nd intensityD it is possile to djust to spei( droplet sizeF he pulse frequeny determines the numer of droplets per time nd therefore the wter onentrtionF e series of photogrphs showing the genertion of wter droplet is shown in (gure TFID tken from IIWF sn the middle of the droplet genertorD the glss pillry n e seenF sn the third imgeD the ejetion of the droplet is shownD whih is followed y retrtion of the remining wter k into the pillryF pigure TFIX qenertion of mirodrop with the piezo injetorF sn the third imgeD the droplet is ejeted nd the remining wter olumn retrts k into the glss pillryF 6.2. Syringe Nanoliter Injection Calibration System UU 6.2 Syringe Nanoliter Injection Calibration System feuse the existing lirtion instruments were not dpted to generte wter onentrtions s low s severl tens of ppmv nd the filing of the mirodrop genertor during the preprtion of our roll mesurement mpign @see hpter UAD n lterntive lirtion systemD the yE ringe xnoliter snjetion glirtion ystem @xsgAD sed on very low injetion rte syringe pumps ws developed in the frmework of this thesisF st ws developed to o'er more roust nd fully utomtized method to regulrly lirte wter vpor isotope rtio mesurements t low volume mixing rtio @vmrA with liquid wter stndrdsF en dditionl gol ws to wste s little stndrd wter s possileD thus requiring wter injetion rtes s low s severl tens of nl per minute to mth the optiml onentrtion rnge of our ypEgie spetrometerF e shemti of the lirtion instrument is shown in (gure TFPF et the ore of xsg re two high preision syringe pumps @rrvrd epprtusA tht n injet two di'erent stndrd wters into seprte evportion hmers TFPF e dry rrier gs is onneted to oth of the injetion hmersF feuse of two upstrem instlled mss )ow ontrollers @wpgD fronkhorstAD the )ow rte through eh of the hmers n e individully djustedF fehind eh evpE ortion hmerD n eletroni threeEwyEvlve is onnetedD whih llows to seletD whih of the two evportion lines is onneted to the ypEgie spetrometerF ypillyD one of the two injetion lines @4mesurement line4A is onneted to the ypEgie spetrometerD wheres the other one @4wste line4A is onneted to supplementry vuum pumpF sn front of the outlet to the ypEgie spetrometerD n upstrem pressure regultor @fronkhorstA hs een instlledD ehind whih vuum pump is onnetedF his enles setting the gs )ow rte in the mesurement line independently of the )ow rte through the spetrometer nd to stilize the pressure in the mesurement lineF he di'erene etween inoming nd outgoing )ow is utomtilly ompensted y n dditionl )ow to the vuum pumpF o provide stle onditions lso in the wste lineD proportionl vlve with n dditionl vuum pump downstremD is onneted to the other exit of the two threeEwyEvlvesF ith this vlveD the pressure in the wste line is typilly djusted to the sme pressure s in the mesurement lineF feuse of the two independent linesD it is for exmple possile to initilize stle injetion of two di'erent stndrds t the sme time nd to quikly swith etween the two stndrds y simply hnging whih of the evportion hmers is onneted to the spetrometerF elternE tivelyD it is lso possile to injet the sme wter stndrd in oth lines ut t di'erent wter onentrtions to investigte wter onentrtion dependeniesF en dditionl threeEwyEvlve t the outlet to the spetrometer llows to lso onnet smE ple gs nd to quikly hnge etween lirtion nd mesurementF o inrese the stility of the devieD the entire lirtion setEup is mounted into thermlly insulted IW inh oxD whih is stilized in temperture with sh regulted peltier in omintion with two mixing fns @vird ehnologyD uperoolAF sn dditionD this mkes the lirtion setEup esily trnsE @qRVAD wheres the other syringe ws (lled with strongly enrihed stndrd @fiPAF pigure TFSX wesurement using the two seprte injetion lines in xsgF yne syringe injeted slightly depleted wter stndrd @qRVAD wheres the other syringe ws (lled with fiPD strongly enrihed stndrdF sing the two di'erent linesD it is possile to mke muh fster hnges of wter onentrtion or wter stndrd thn would e possile with only one syringe pump sn (gure TFTD lirtion run with the IHHEµl syringe under onstnt onditions is shownF he wter injetion rte ws set to ISH nlGmin nd the ir )ow rte to QHH smD resulting in men wter onentrtion of round TTH ppmvF heres the isotope rtios re very stle throughout the lirtion runD n osilltion with mplitude PFP ppmvD thus HFQQ7 of the wter onentrtionD n e oserved in the wter onentrtion mesurementF e pst pourier rnsform @ppA of the wter onentrtion mesurement yields n osilltion period of RPR sF ith n injetion rte of ISH nlGminD this orresponds to n injeted volume of IFHT µlF king the inner dimeter of IFRT mm of the syringe into ountD this orresponds to distne of TQQ µm overed y the plunger of the syringe during one osilltionF his vlue mthes very well the distne of TQS µm tht is spei(ed for one full revision of the led srew of the syringe pump IQTF he osilltion is thus used y inhomogeneities of the turning of the led srew of the syringe pumpF st is lso present with the seond syringe pump nd hnges its period nd mplitude if smller or lrger syringe is usedF sn the isotope rtios of the sme mesurementD this osilltion is not visile nd neither is it in the pp of the isotope rtiosF sn generlD the osilltions of the wter onentrtion re smll enough to not 'et the isotope rtiosF sn sesD 6.2. Syringe Nanoliter Injection Calibration System VQ where it is visile in the isotope rtios @eFgF when lrger syringe is usedAD verging of the isotope rtio over the entire osilltion period is reommendedF Water vapor isotopologues in Antarctica sn the ontext of glolly wrming limte it is ruil to study the limte vriility in the pst nd to understnd the underlying mehnisms IRHF reipittion deposited on the polr ie ps provides mens to retrieve informtion on temperture hnges @through the pleoE temperture dependene of the isotopi omposition of the ieA nd tmospheri omposition @of gs stored in ules in the ieA on time sles from one to lmost one million yersD with suEnnul resolution in the most reent enturies IRIF roweverD it is now widely reognized tht the lirtion of the pleoEthermometer is highly prolemtiF por this reson ttempts to model the glol wter yleD inluding the isotope signlsD re ongoing with the im of providing more physil sis of the isotope E temperture reltionF gurrentlyD there is lrge divergene in the results otined y di'erent modeling strtegiesF he missing link in these model studies is their foring y experimentl dt on the preEdeposition isotopi omposition of the vpor phse omprtment of the hydrologil yleF e propose to mesure the isotopi omposition of moisture rried towrds nd deposited on entrtiD in order to onstrin the numeril modelsF por these resons we hve developed the ypEgie spetrometer desried in this thesis nd mesured wter vpor isotopologues in entrti irF he instrument ws (rst operted t the entrti eserh sttion rollD to ontinuously mesure inEsitu the three stle isotope rtios of tmospheri wter vporF he xorwegin eserh sttion of roll is loted in ueen wud vndD entrti @UP°HI9D P°QP9iD IPUS m FsFlFA t pproximtely PPH km from the entrti ostF roll sttion is one of the few sttions loted t the slope of the entrti ie sheetD whih is exposed to vrying in)uene from the entrti plteu nd the outhern yen IRPF feuse of this it is idelly suited to study the trnsporttion of humid ir from the oen to the entrti plteu s well s ontinentl trnsporttion of tmospheri moistureF he min omplex of the reserh sttion is uilt on ground rokD wheres the ir (eld is loted on the lue ie t pproximtely U km from the min sttion @fF (gure UFIAF 7.1 The Antarctic spectrometer design huring the entrti mpignD the instrument ws mesuring t UIVR m -1 D llowing simultE neous mesurements of r 16 2 yD rh 16 yD r 2 18 y nd r 2 17 yF he generl design of the instrument pigure UFIX he lotion of roll reserh sttionF he min omplex of the sttion is pled on sumontne rokD wheres the ir (eld is U km from the min sttion on the lue ie @mp provided y the xorwegin olr snstituteA is s desried in hpter QF roweverD some di'erenes will e disussed in the followingF huring the mesurement mpignD the instrument ws powered y two internl swithing power supplies @wen ell hEIPS nd hu vmd vUSAD providing S nd PR nd ISD respetivelyF snsted of fronkhorst )ow ontroller @fF hpter QAD the pressure inside the instrument ws stilized with n djustle vuum pump t the exit of the instrument @uxp VRFRexhgfAD ontrolled with sh loop regulting the vity pressureF he )ow ws regulted with soni nozzle t the inlet of the instrumentF he soni nozzle is silly tue whih hs on the upstrem side onvergent ross setion nd smooth rounded outlet setion with smll opening in the enter through whih the )ow hs to pssF feuse of this restritionD the )ow is elerted to supersoni speed in the opening nd the )ow rte through the nozzle eomes liner funtion of the inlet pressure nd independent of the downstrem pressure IRQD s long s the downstrem pressure is signi(ntly smller thn the inlet pressure @p in > 1. Laboratoire des Sciences du Climat et de l'Environnement @vgiA ws employedF e shemtis of this system is shown in (gure UFTF yn the syringe pump @vegto IHHD kdiE enti(AD TH mv syringe is injeting lose to the minimum injetion rte of the pump @typilly IQFQ µvGminAF he wter is pushed through IGIT inh iiu tuing nd split into two strems to redue the rte tht is injeted into the evportion hmerF rt of the injeted wter is send to wste inD wheres the other portion is injeted vi heted pillry @IHH µm inner dimeterD pproxF IH m lengthA into glss hmer @ISH mA tht is heted to IRH°gF feuse of omplete evportion of the injeted wter t the tip of the pillryD no frtiontion oursF en djustle dry gs )owD either dry syntheti ir from ottle or mient irD dried within rtridge with desint @hrieriteAD is onneted to the injetion hmerF he ir )ow through the glss hmer is mintined y the spetrometer itself in omintion with n dditionl pump with )ow regultor onneted in prllelF he djustle )ow to the seondry pump lso o'ers further possiility to regulte the wter onentrtion in the lirtion system more preiselyF ypillyD the totl gs )ow through the evportion hmer is set to P lGminF

δ (cal) s = δ (t) 1 + δ (m) s -δ (m) 1 × f @SFIA with f = δ (t) 2 -δ (t) 1 / δ (m) 2 -δ (
b s = b 1 + (b 2 -b 1 ) × δ s -δ 1 δ 2 -δ 1 @SFRA
δ corr. = δ meas. - b H 16 2 O -m × H 16 2 O @SFSA
f cor. = R real R meas × R V SM OW @UFIA
with R real the rel isotope rtioD R V SM OW the isotope rtio of wyD nd R meas the meE sured isotope rtioF heres the (rst lirtions with the uler were done t one wter onentrtion onlyD ll lter lirtions were done t three di'erent wter onentrtions to tke possile wter onentrtion dependene of the isotope rtios into ount @fF hpter SAF feuse of the frtiontion etween liquid nd gs phse wterD the reservoir eomes inresE ingly enrihed in the hevier isotopologuesF gonsequentlyD this enrihment hs to e tken into ount for the lirtion mesurementsF o evlute if the enrihment in our se hs to e ounted forD we mke n estimte of the enrihment throughout the mpignF he uler reservoir ws (lled with pproxF 0.57 l r 2 yF yver the entire mesurement periodD

)ow through the uler volume ws mintined for totl of WI h nd interruptedD when no lirtion mesurements were doneF huring this timeD the verge wter onentrtion generE ted y the uler ws IVIR ppmvD whih orresponds t gs )ow rte of IHH sm to wter injetion rte of 145.8 nlGminF he mount of wter evported over the entire mesurement period is thus 91 h • 145.8 nlGmin = 0.8 mlF por the verge wter temperture of ITFVS °g in the ulerD the frtiontion ftor for δ 2 r nd δ 18 y @rtio of isotopi omposition in vpor nd liquid phseA re lulted to e 0.945D nd 0.99 respetively IRRF e n thus lulte the inresing enrihment of the liquid wter reservoir ssuming yleigh prtiontion @fF setion IFPFPDIRSAX

R R 0 = f α-1 = 0.55 -0.8 • 10 -3 0.55 α-1 @UFPA
por δ 2 rD this leds to 1 -R R0 = -0.08 nd for δ 18 y to 1 -R R0 = -0.01 D inditing tht the hnge in the isotope rtios of the reservoir wter is smller thn the mesurement preisionD if one ssumes tht the isotopi omposition of the uler wter is equl to wy nd R 0 = 1F es the wter is olleted in entrtiD it is depleted in the hevier isotopes nd the di'erene is even smllerF en independent mesurement of the reservoir wter y swD done y rF tnsen of the genE ter for ssotope eserh in qroningen on smple of preEmpign nd postEmpign wterD shows indeed no di'erene in the isotope rtios of the two wter smplesF his mesurement yielded δ 2 r= -348.6 nd δ 18 y= -43.57 for the preEmpign wter nd δ 2 r= -348.6 nd δ 18 y= -43.52 for the postEmpign wterD on(rming the ove estimte to within the mesurement uries @respF HFQ nd HFI for δ 2 r nd δ 18 yAF gonsequentlyD no orretion for this e'et ws requiredF he isotope undnes in the wter vpor were lulted ssuming equilirium frtiontion etween liquid nd gs phse with the frtiontion ftors sed on the formultion of rorit nd esolowski IRR nd using the wter temperture mesurementF he verge wter temE perture inside the uler ws 16.8 ± 1.5°gD whih orresponds to delt vlues of ERHIFR nd ESQFHV for δ 2 rD nd δ 18 yD respetivelyF he mximum wter temperture during the mesureE ment mpign ws PH°g nd the minimum IIFV°gD orresponding to vritions of the isotope undne in the vpor phse wter in rnge of δD max -δD min = -399.3 + 404.9 = 5.6 for pproximtely one hour nd onsisted of three onentrtion stepsF glirtions were done one in the morning @round UXQH mA nd one in the evening @round UXQH pmAF sn (gure UFIPD the isotope delts for ll lirtion mesurements during the roll mission from HVEHP till IVEHP @II dysA re shownD verged over eh stle onentrtion step nd orreted for the temperture dependent frtiontion inside the ulerF he totl vrition of the delt vlues in the lirtions for the entire mesurement periodD fter orretion for gs temperture vritionsD is PS for δ 2 rD IRFS for δ 17 y nd VFU for δ 18 yF hese reltively lrge di'erenes re minly due to instrumentl driftD indued y temperE ture instilities inside the mesurement ontinerF enother reson is wter onentrtion dependene of the isotope rtios tht is visile for ll three isotopologues @see lso hpter SAF he ehvior of δ 2 r nd δ 17 y with the wter onentrtion hnges etween di'erent lirE tion runs nd sometimes its slope even hnges signF e suppose tht the hnging ehvior of this dependeny is result of residul optil fringes with struture tht hnges on the time sle of the mesurements @pproxF I dyA tht interfere with the sorption spetr nd introdue devitions @see hpter R for more detiled disussionAF es the hnge of the onE (a)

pigure UFIIX ixemplry lirtion mesurement with the uler entrtion dependene etween two lirtion mesurements proved impossile to preditD we deided not to ttempt orretion of δ 2 r nd δ 17 yF por δ 18 y @(gure UFIPAD the wter onentrtion dependene of the delt vlues reprodues eE tween the di'erent lirtion runsF feuse in generl only three di'erent wter onentrtion steps were mde per lirtionD it would not e dvisle to (t the onentrtion dependeny of δ 18 y with higher order polynomilF e thus ssume liner dependenyD whih is determined with (t to the ensemle of the lirtion steps of ll lirtionsF e ssume tht the slope is onstnt for ll lirtion runs nd thus (t single glol slope to ll runs simultneouslyF e liner (t to δ 18 y yields slope of (2.3 ± 0.2 × 10 -3 ) Gppmv @(gure UFIQAF sn (gure UFIQD pigure VFIX A hi'usionElimited nd A equilirium limited prtiontion n produe the sme supersturtionF hue to di'erent resons for the supersturtion @see textAD they produe disE tint isotope signlsD whih n e used to determineD whih mehnism is responsileF sn the lower pnelD the reltive humidity in lose proximity to the ie rystl is given in green nd δh in redF pigure from iFtFwoyer ISQ qermny @usA ws idelly suited for this studyD s it enles produing the right onditions for superEsturtion to our during n expnsionEdriven loud formtionD nd eing equipped s it is with extrtive smple ports nd two inEsitu longEpth length optil sorption gs ells of the hite designF se loud formtion nd the possile mehnisms were studied in the frmework of the ssoE loud projetD n interntionl ollortion funded y the xtionl iene poundtion @http: //www.nsf.gov/AD the heutshe porshungsgesellshft @http://www.dfg.deA nd iurohmpE P @http://www.eurochamp.orgA etween the group of iF woyer of the heprtment of qeophysE il ienes of the niversity of ghigo @ogAD the snstitute for weteorology nd glimte eserh etmospheri eserh of the usD the group of F iert of the genter of mrt snE terfesD ehnishe niversität hrmstdt @hA nd hysiklish ehnishe fundesnstlt @fA in frunshweigD qermny nd the vshy of the niversity of qrenole s djoint prtE nerF 8.1. General set-up IIQ qs phse wter nd isotopi omposition ws mesured with two inEsitu hve spetrometersF he og developed system tht mesured r 16 2 y nd rhy t PFTS µm @grsEsA nd the niversity of hrmstdtGfGus groups ontriuted with similr instrumentD lled ssotope esheEgsEinEloudEhv @syEeiAD desried in detil in the disserttion of tn gF rig VUAD tht mesured r 16 2 y nd r 18 2 y t PFTRµmF foth of these instruments will lso e disussed in more detil in the hh theses of uF vm @niversity of ghigoA nd fF uühnreih @niverE sität hrmstdtGf frunshweigAF e prtiipted with the ypEgie spetrometer @ssA nd the syringe lirtion system developed in the frmework of this thesis nd supported the us with the opertion of their ypEgie spetrometer @esontorverstärktes sserdmpf esorptions pektrometerD ewsEssoAD whih ws lso uilt in qrenole nd whih is sed on our own spetrometerF o mesure the isotopi omposition of the ie rystlsD one of the ypEgie spetrometers ws onneted ehind pumped ounterE)ow virtul imptor @gsA ISR tht seprtes ie prtiles lrger thn set utEo' size from the gs )owF he gs is desried in more detil in setion VFPF he seond ypEgie spetrometer ws diretly onneted to the loud hmer nd mesured vi n extrtive heted tuing the isotopi omposition of totl wterF sn ddition to these four instrumentsD the lredy existent eshe gs extrtive hv @eeA nd frost point mirror @wfA mesured totl wter onentrtion vi n extrtive line nd es detiled disussion of the funtioning of the gs would go well eyond the sope of this workD it is only rie)y introdued hereF e more thorough desription n e found in IST!ISVF sn (gure VFSD shemti representtion of the gs is shown @from ISVAF e smple )ow @f s A inluding prtiles E in our se the ir from the loud hmer E is drwn into the virtul imptor y vuum pump @indited s pump )ow in the (gureAF upplementl ounter)ow @f cf A of prtileEfree gsD typilly dry syntheti ir stremD is sustined to intertilly remove smller prtiles from the )ow through the gsF ynly prtiles ove ertin mss ndD euse of sme densitiesD ove ertin size @the soElled ut size or utEo' sizeA trverse the ounter)ow euse of their lrger inerti nd re seprted from the ulk prt of the smple )owF he prtileEfree ounter)ow onsists of frtion @the e'etive ounter)ow f ecf A tht is evuted y the onneted pump nd nother frtion @f of A tht serves s rrier gs for the seprted prtiles in the output

)ow @f cf = f ecf + f of AF IIW (a)
pigure VFSX hemtis of the pumped ounter)ow virtul imptor @gsAD (gure from ISV he ut size is typilly de(ned s the size t whih SH7 of the prtiles re trnsmitted through the gs into the output )ow ISUF st is minly dependent on the rtio of volumetri e'etive ounter)ow nd inoming smple )owD ut lso depends on other prmeters suh s input pressureD the pressure in the gs ISVD visosity of the ir nd density of the prtilesF es the inoming smple )ow n e lrger thn the output )ow of the gsD the seprtion of prtiles omes long with n enhnement of the smple onentrtionD whih equls the rtio of smple )ow nd output )owF huring the ssoloud mpignsD the ut size ws typilly round PFS µm nd the enhnement ftor in the wter onentrtion 3.72F es desried oveD the seprtion in the gs depends on the inerti of the prtilesD whih mens tht it requires onstnt prtile speeds nd thus onstnt volumetri )owD independent of the pressure in the gsF roweverD the ypEgie instruments work with onstnt mss )owsD whih mens tht the volumetri )ow inreses t lower inlet pressuresF o mintin pressure independent onstnt volumetri )ow through the smple outlet of the gs with onstnt mss )ow through the ypEgie instrument ehindD mss )ow ontroller ws onneted in prllel to the ypEgieF he )ow through the wpg ws then regulted suh tht the volumetri )ow in the gs remined onstnt @fF (gure VFTAF 8.3 Calibration of total water and isotope ratios 8.3.1

Calibration of OF-CEAS he totl wter onentrtion mesurements of ewsEsso were lirted ginst the wter onentrtions of eeF por thisD ll setions of the mesurements during the mpign with stle wter onentrtionsD t whih oth ee nd ieEsso were mesuring totl wterD were usedF usequentlyD the verge for oth instruments over eh of these setions ws luE (a)

pigure VFTX he volumetri )ows t the smple outlet of the gs during n expnsion experiE mentF es the mss )ow through the ypEgie instrument stys onstntD the volumetri )ow inreses with lower pressuresF o sustin onstnt totl mss )ow t the smple outletD n wpg with pump is onneted in prllel to the ypEgie nd the )ow is deresed with lower pressureF vower pnel shows the pressure nd temperture in the eshe hmer for typil expnsion experimentF ltedF es ieEsso ws mesuring in four di'erent wvelength regions during the mpign @fF VFIFIAD four di'erent dtsets were thus onstrutedF es n exmpleD in (gure VFUD the r 2 y lirtion is shown for the r 2 18 y wvelength region t UPVT m -1 F e liner funtion ws (t to the plot of the wter onentrtion mesured y ews vsF tht mesured y ee nd yielded n interept of 0.1±0.07 ppmv nd slope of 0.76±0.01F

he lrge di'erene with unity is due to n initilly erroneous onversion ftor from line pro(le to onentrtion in the (t (le of the ypEgie spetrometerF he wter onentrtions of ss were not lirted in ssoloudR s ss ws onneted lmost lwys ehind the gs nd no diret omprison ould e mdeF ine ss mesured in sme wvelength rnge tht hd een lirted previouslyD this ws lso not neessryF he isotope rtio mesurements of ewsEsso nd ss were lirted with xsg t lest twie dyD one efore the experiment in the morning nd one fter the experiment in the eveningF feuse of the limited time ville for the lirtionsD we deided to fous the liE rtion on the orretion of the wter onentrtion dependeny nd only one isotope stndrd ws used for mesurements t di'erent wter onentrtionsF sn the se of ssD the onenE trtion dependeny ws determined for omintion of the two lirtions efore nd fter the mesurement @fF SFIA nd ws used for the orretion of the mesurementsF he vrition etween the two lirtion mesurements ws in generl omprle to the vrition of meE surement steps in the individul lirtionsF por onentrtions ove RH ppmvD the stndrd IPI (a)

pigure VFUX glirtion of the r 2 y mesurement of ewsEsso vsF eeF por the lirtionD ll setions with stle onditions in the ssoloudR mesurements were identi(ed nd the verge of r 16 2 y for ee nd ewsEsso were lulted nd plotted ginst eh otherF he stndrd devition on the mesurement is smller thn the size of the dt pointsF devition of the orretion funtion is IV for δ 2 r nd PFI for δ 18 yD for onentrtions elow thisD the stndrd devition eomes signi(ntly lrger euse of the strong nonElinerity of the onentrtion dependeneF 8.3.2 Calibration of in situ measured HDO/H 2 16 O ratios for CHI-WIS por the ghigoEuilt inEsitu hv wter spetrometer grsEsD the experimentlly deterE mined vlue of the deuterium isotope rtio

2 R = [HD 16 O] sample /[H 2 16 O] sample [HD 16 O] VSMOW /[H 2 16 O] VSMOW
ws lirted ginst the @lirtedA R of ewsEssoF enlog to the lirtion of the wter onentrtion for ewsEssoD ll setions of the dt with stle r 2 y nd 2H were identi(ed over the entire mesurement periodF es ewsEsso ws not lwys mesuring rhyD only those experiments were onsideredD in whih n rhy mesurement ws ville for oth instrumentsF es ll stle setions were usedD the dt inlude mesurements t di'erent pressures nd efore nd fter expnsion experimentsF hi'erent lirtion strtegies were studied in order to lirte the isotope rtio rhyGr 16 2 y of grsEs @in the following R CHIWIS A with the lirted mesurements of ewsEssoF emongst othersD seprte lirtion of r 16 when orretion is pplied to the isotope rtio diretlyD ssuming qudrti reltion etween R CHIWIS nd R Rewas F he (t ws weighted using the stndrd devitions of the ewsEsso dt points only @ω i = 1 σ 2 i AD onsidering tht the error on the ews dt is typilly of the sme size s nd osionlly up to R times lrger thn tht of grsEs dt @fF (gure VFVAF he (t (a) pigure VFVX he deuterium isotope rtio mesurements @IP in totlA of ewsEsso plotted ginst those of grsEisF he error rs represent 1σ stndrd devitionsF e qudrti funtion ws (t to the dt to orret the grsEis mesurement with the lirted mesurement of ewsEssoF gives the following reltionX

R Rewas = -4 + 1.27 • R CHIW IS + 0.11 • (R CHIW IS -12) 2 @VFIA
he residul of the (t indites di'erene of severl hundred permil etween the isotope rtios of grsEs nd ewsEsso fter the lirtionF his is euse dt from the entire ssoloudR mpign ws used for the lirtion (tF feuse of the smll mount of stle mesurement setions tht ould e ompredD only limited mount of dt points ws ville nd it ws not possile to mke one seprte lirtion for eh mesurement dyF his mens tht the drift of the two instruments is lso inluded in the (t nd dds to the unertintiesF sn dditionD ewsEsso fetures lrge unertinty on the isotope rtios t very low @`S ppmvA pigure VFWX ssotope rtio mesurement @rhyGr 16 2 yA of grsEs nd ewsEsso during the ssoloudR mpignF A grsEs is not lirted for driftF e di'erene of nerly SHH n e seen in the stle setions in the eginning nd the end of the experimentD where oth instruments should gree A grsEs dt lirted ginst ewsEsso mesurements for the entire mesurement mpignF he two instruments gree etter thn IHH D whih is muh smller thn the overll hnge in the isotope rtios nd orresponds to reltive error on the rtio of pproxF I7F the mesurementsD nd orresponds to reltive mesurement ury of I7 on the @enrihedA deuterium rtioF 8.4 Typical expansion experiment por the ssoloud mpignsD stndrd experimentl protool ws estlished to study ie loud formtion proessesF et the eginning of mesurement dyD wter ws dded to the hmer ir until the prtil pressure ws lose to sturtion pressure PQF his wter ws strongly doped with rhy @ 2 R = 10 to 20A to enhne the otherwise reltively wek rhy signlF en experimentl run ws strted when the ir in the loud hmer ws homogeneously mixed nd the wter onentrtion s well s the isotopi omposition were stleF por eh expnsion experimentD the pressure inside the hmer ws deresed y evuting hmer ir with the vuum pump onneted to the top of the loud hmer @fF (gure VFIHAF ressure drops were either from QHH mr to PQH mrD PQH mr to IUH mr or QHH mr to IUH mrD nd took few minutes to hieveFF he derese of the pressure inside the hmer led to n diti ooling of typilly SEU u of the hmer irF es the prtil pressure of wter ws lose to sturtion efore the experimentD this derese in temperture leds to supersturtion in the hmer ir ndD in the presene of ieEondenstion nuleiD susequently to the formtion of n ie loudF es ieEondenstion nuleiD di'erent types of erosol prtiles were usedD mongst others erizon est hust @ehA nd ulfuri eid @r 2 y 4 AF he degree of supersturtion tht is rehed IPR 8. Water isotope fractionation in simulated ice clouds during n expnsion experimentD s well s size nd mount of formed ie n e in)uened y the seletion of spei( erosol nd the mount of erosol prtiles tht re dded ISWF hroughout the mesurement mpignsD expnsion experiments with ie loud formtion were rried out t di'erent initil hmer tempertures rnging from ERH°g to EVS°gD orresponding to wter sturtion vpor pressures of 12.8 down to 0.024 PQF e typil expnsion experiment is shown in (gure VFIHF es disussed oveD the three inE struments EeiD ghiEs nd ssoEei mesure inEsitu gs phse wterD in the se of ghiEs lso inluding rhyD nd for ssoEei inluding r 2 18 yF sn the upper pnel of (gure VFIHD the di'erent wter onentrtion mesurements re shownF wf nd ee s well s ewsEsso mesure totl wter vi two di'erent extrtive linesD in the se of ewsEsso together with one @r 2 18 y or rhyY ssoloudRA or three @rh 16 yDr 2 18 y nd r 2 17 yY ssoloudQA of the rre wter isotopologuesF ss ws onneted ehind the gs nd mesured ie phse wter inluding the three rre isotopologuesF he enhnement in the wter onentrtion tht ours in the gs @disussed in setion VFPAD ws orreted forF purthermoreD the wter onentrtions orresponding to sturtion vpor pressure is shownF hen the vuum pump is turned onD the pressure strts to derese with pproxF 0.22 mr/sF et the sme timeD the ir temperture dereses in less thn T min more thn VFS°g @lower pnel in (gure VFIHAF he derese of ir temperture lso results in derese in sturtion wter vpor pressureF hen ritil supersturtion is rehedD wter vpor strts to form ie prtiles on the present nuleiF he ie formtion n e seen in n inrese in totl wter @eeD wf nd ewsA nd derese in wter vpor @ei nd grssA in the upper pnel of (gure VFIHF sn the enter pnelD the isotope rtio rhyGr 16 2 y mesurement for gs phse @grsEsAD totl wter @ewsEssoA nd in the gs ie @ssA is shownF sn the isotopi omposition @enter pnel of (gure VFIHAD the rystlliztion results in derese of the isotope rtio rhyGr 18 2 y in gs phse wter s the hevier isotopologues preferentilly rystllizeF he mesurement of ewsE sso shows tht totl wter eomes inresingly enrihed during the ie loud formtionF sf the wter onentrtion nd isotopi omposition would hnge only due to the removl of hmer ir y the vuum pumpD the isotope rtio in totl wter would remin reltively onstnt s ll isotopes re prtilly removed homogeneouslyF he strong inrese of the totl wter isotope rtio indites wter )ux from the hmer wllsD with strong isotopi enrihment ompred to the hmer irF he mesurement of ss ehind the gs shows n inrese of the reltive undne of rhy in the ie phseD whih is expeted euse of preferentil rystlliztion of the hevier isotopologuesF he isotope rtio does not derese to the initil vlue of the rrier gs ut remins highly elevted @ 2 b IHAF his is due to wllEdsorption tht leds to lrge memory e'et t very low wter onentrtionsF es the rrier gs is very dryD dsored rhy moleules on the wlls re not e0iently repled y H 16 2 O ut only slowly relesedD leding to the high (a)

pigure VFIHX pper pnelX he di'erent mesurements of vpor phseD totl wter nd ie phse ehind the gs nd the ie wter ontent lulted s the di'erene of ee nd ei mesurementF he ornge dshed line indites the onentrtion orresponding to sturtion wter vpor pressureF genter pnelX rh 16 yGr 16 2 y for totl wter @ewsEssoAD gs phse wter @grsEsA nd ehind the gs @ssAF vower pnelX hmer pressure @in lueA nd hmer ir temperture @in redA (a) pigure VFIIX δ 18 y mesurement of the ie ehind the gs during the experiment shown in (gure VFIHF sn the eginning of the ie formtionD δ 18 yGr 16 2 y inreses pproxF SH F huring the experimentD the hnge is smller thn the noise levelF isotope rtio vluesF sn (gure VFIID the ie phse δ 18 y mesurement of ss ehind the gs is shownF o guide the eyeD smoothed urve with wedin (ltering over TH points @RH sA t time is shown in redF sn light lueD the orresponding r 16 2 y mesurement is givenF por this experimentD no totl wter δ 18 y mesurement is villeD s ewsEsso ws mesuring rhy nd r 16 2 y onlyF he ssoEei gs phse mesurement of r 16 2 y nd r 18 2 y is still eing nlyzed y our ollegues t hrmstdt university nd not yet ville t the time of this writingF hen the (rst ie rrives ehind the gsD 18 inreses y pproxF SH from IFIS to IFPF huring the pproxF IT min of the ie loud expnsion @from IQXSU h till IRXII hAD the hnge of the isotope rtio is within the noise nd of the mesurement nd no trend n e identi(edF he initil inrese in 18 is proly due to higher reltive undne of the hevier isotopologues in the wter vpor inside the hmer ompred to the dry syntheti irF es isotopi hnges in the se of δ 18 y re very smllD possile hnges ould unfortuntely not e resolved with our ypEgie spetrometer t the wter onentrtions mesured during the ssoloud mpignsF sn dditionD the seprtion of the ie prtiles in the gs leds to further smoothing of the signlD whih mkes the temporl resolution of the ie formtion even more di0ultF he strongest enrihmentD whih n e found in newly formed ie prtilesD n not e mesured with the gsD s these prtiles re too smll to e seprtedF huring rystl growthD the ie eomes isotopilly lighter due to depletion of the gs phse in the hevier isotopologuesF 8.4. Typical expansion experiment IPU 8.4.1

Comparison of total water measurement of APeT/MBW and Rewas/SIRI sn (gure VFIHD signi(nt di'erene etween the totl wter mesurement of ee nd wf on one side nd ieEsso on the other side n e seenF heres the three r 2 y mesureE ments show di'erenes smller thn I ppmv for the stle region efore nd fter the pressure dereseD the mesurement of ieEsso indites more rpid nd stronger inrese in onE entrtion thn the two other instrumentsF his di'erene n e oserved in prtilly ll of the mesurementsD with ieEsso lwys showing stronger nd fster response to the pressure derese thn ee nd wfF sn ftD the mesurements of ieEsso pper to e driven more diretly y the pumpingEindued pressure hngeF e possile explntion for the di'erenes etween the totl wter onentrtions mesured y ee nd wf on one extrtive line ompred to the wter onentrtion mesured y ewsEsso on nother extrtive line ould e tht the mesurement of one or severl of the instruments ws 'eted y the temperture or pressure hnges during n expnsion experE imentD either diretly or euse these introdued systemti errors in the instrumentsF st is lso importnt to notie tht ieEsso is mesuring with onstnt pressure nd temperture inside the instrumentD wheres ee nd wf mesure wter numer density t hnging pressure nd tempertureD whih in the se of ee requires orretions for deresing totl ir numer density nd inresing numer density due to drop of the tempertureF ystemti errors euse of temperture or pressure hnges would e ovious if the two instruE ments on the sme extrtion line would show di'erent redingsF roweverD the mesurements of ee nd wfD whih were lwys onneted to the sme extrtion lineD re in reltively good greement throughout the expnsion experimentsD espeilly s fr s the overll shpe of the wter onentrtion hnges is onernedF purthermoreD ee nd wf lso greed with other instruments smpling t di'erent positions of eshe @lso inluding level IA during the interomprison mesurements of the equs mpigns I nd P ISSF et the sme timeD the wter onentrtion mesured y ewsEsso nd ss greeD when onneted to the sme extrtion lineF pigure VFIP shows n exmple of the good greement etween ee nd wf nd etween ewsEsso nd ss for one experimentF his mkes it highly unlikely tht the prolem is relted to mesurement prolems with one of the instrumentsF purthermoreD ee mesures the wter onentrtion optilly nd wf vi dew point mirrorD thus y two very di'erent tehniquesD nd ommon error etween these two instruments n prtilly e exludedF sn the se of ewsEsso nd ssD oth instruments mesure the wter onentrtion y the ypEgie tehniqueF roweverD oth instruments re mesuring in di'erent spetrl regions with di'erent temperture dependenies of the investigted sorption linesF sn dditionD oth instruments re stilized in vity tempertureD pressure nd )ow rteD whih mkes them virtully insuseptile to pressure nd temperture hnges in the eshe hmerF pinllyD the hrteristis of the wter onentrtion hnge mesured y ewsEsso during n expnsion experiment does not hnge etween the di'erent spetrl regions for rhy nd r 2 18 y in whih it ws mesuring during ssoloudRF hereforeD the di'erenes in the wter onentrtions hve to e relD either euse of inE pigure VFIPX huring the expnsion experimentsD the wter onentrtion mesured y @A ee nd wf re in good greementD s re the mesurements y ewsEsso nd ss @A homogeneities in the loud hmer itself or euse of prolems inside the extrtive tuingF feuse of the limited size of the loud hmerD there is permnently n exhnge of wter inE side the hmer with wter on the hmer wllF heres this exhnge rehes n equilirium under stle onditionsD n inresed ddition of wter from the wlls n e oserved during the expnsion experimentsF sn dditionD oundry lyer lose to the hmer wll is strongly in)uened y the temperture of the hmer wllD whih stys reltively onstnt during the pumpEdown experimentsD in ontrst to the gs temperture in the hmerF he extrtive tuing through whih ewsEsso ws mesuring during the mpigns smples the hmer ir t distne of IQ m from the hmer wllD in ontrst to the tuing of ee nd wfD whih extrts ir t distne of QH to RH m from the wllF hue to the smller distne from the wllD the mesurement of ewsEsso ould thus e more 'eted y )uxes oming from the wlls thn tht of the other two instrumentsF roweverD )ow simultions of the onditions enountered in the eshe hmer during evution nd under stle onditions show tht this is not the resonF his is lso on(rmed y the oserved rdil temperture pro(le in the hmerF sn (gure VFIQD the horizontl gs temperture pro(le inE side the hmer in proximity to the hmer wll is shown for the expnsion IR of IREHQEPHIQF heres the sensors t distne of up to QH mm from the wll show temperture redings tht re very lose to the wll tempertureD the sensor t IHH mm is in good greement with the men gs temperture in the hmerF he hmer ir ppers to e lredy homogeneously mixed t this distne nd the in)uene of diret )ux from the wll seem to e very smllF IPW feuse of thisD strong impt of the wll )uxes on the mesurement in ewsEsso tht would e neessry to explin the reltively lrge di'erenes etween eeGwf nd ewsEsso pE pers very unlikelyF sn ddition to the di'erent rdil positionD the two extrtion points of eeGwf nd (a) (b)

pigure VFIQX A he horizontl gs temperture pro(le in the eshe hmer lose to the hmer wll during n exemplry expnsionF emperture sensors were instlled in therml ontt with the wll nd t distnes of QD IHD QH nd IHH mmF es refereneD the men gs tempertureD verged over severl sensors in the entire hmer is shownD A he vertil gs temperture pro(le in the loud hmer t the di'erent ess levels of the hmer ewsEsso re lso instlled t di'erent heights of the hmer @fF (gure VFPAF heres ewsE sso is mesuring t IQS m ove the se of the hmerD ee nd wf smple t height of T mF es wrm ir hs lower density thn old irD wrm ir rises nd there is vertil temperE ture grdient in the eshe hmerF his mens tht t the extrtion point of eeGwf on the third level of the eshe hmerD the temperture will e slightly higher thn t the ottomD where ewsEsso is mesuring @level IAF he vertil temperture grdient is shown exemplrily for the sme expnsion experiment s previously the horizontl temperture pro(le in (gure VFIQF here lerly is di'erene of pproxF HFS °g in the gs temperture t the top of the hmer ompred to the ottomF he shpe of the temperture hnge during the expnsion is very similr on ll levelsD s re the solute temperturesF his indites tht the hmer ir is reltively well mixed in the entire hmer nd di'erenes etween the di'erent levels in the hmer re proly not n explntion for the di'erenes etween the two totl wter onentrtion mesurementsF sn (gure VFIRD two susequent expnsion experiments re ompredF sn the (rst experimentD ee nd wf were exeptionlly onneted to n extrtive line on level P of the loud hmer @pproxF R mAD wheres they were onneted to their stndrd port on level Q @T mA in the seond experimentF he di'erent wter onentrtions in the two experiments n e explined y the di'erent onditions during the two expnsions @expF PH ws pumpEdown from PQH to IUH mr nd expF PI from QHH to IUH mrAF st is noteworthy tht despite the di'erent sn (gure VFISD the wter onentrtion mesurement of two expnsions is shown @top pnelA together with the prtile density mesured with two optil prtile ounters @ygD ive PIHHD seond pnelAF he prtile density is with pproxF 500 m -3 higher in (gure VFIS thn in (gure VFIS @100 m -3 AD the wter onentrtion is the oppositeF vower ie nulei numer onentrtions t higher wter onentrtions llow the formtion of fewer ut lrger ie rystls @out IHH µmA in experiment VFIS ompred to out SH µm in experiment (gure VFISF feuse of the lrger prtile sizesD the ie rystls grow more quikly to eyond the uto' size of the gs nd re thus sulimted in the smple ir rriving in the ypEgie spetrometerF sn the se of experiment V of (gure VFISD the wter onentrtion ehind the gs ontinE ues to inrese for pproxF UH s fter the strt of the experimentD wheres in experiment IS @(gure VFISAD it tkes pproxF RH s longer for ie rystls to e detetle y the ypEgie instrumentF xote tht this di'erene in ie rystl size is lso visile in the onset ehvior of the two di'erent optil prtile ounters whih hve di'erent lower detetion limitsF sn (gure VFITD n expnsion experiment t ETH°g is shownF sn the top pnelD the wter onentrtion mesurements with n initil wter vpor onentrtion of RH ppmv re shownF he enter pnel shows the rtio rhyGr 16 2 y in the vpor phseD totl wter in the gs phseD s well s in the ie phse s mesured ehind the gsF hue to hevier wll ie tht is relesed during the pressure dereseD the rh 16 yGr 2 16 y rtio inresed from IHFT to IIFI during the experimentF he isotope rtio mesured y ss ehind the gs inreses in the eginning of the experiment @until IIXHS hAD then dereses for pproximtely one minuteD efore it inreses ginD to level o' t higher thn efore the expnsionD due to the ove disussed wllEindued memory e'et for rhyF he oneEminute long derese of the rhyGr 16 2 y rtio n e oserved in severl of the experiments @eFgF lso in (gure VFIHAF his dip in the isotope rtio is proly due to the inresing in)uene of wll ie throughout the expnsion experimentF sn the eginningD the ie is eoming progressively enrihed euse of preferentil rystlliztion of the hevier isotopologuesF es the vpor phse eomes more depleted in the rre isotopologuesD more r 16 2 y moleules rystllize nd the isotope rtio of the ie dereses slightlyF feuse of highly enrihed wter oming from the wllsD the totl wter isotope rtio inreses gin nd s this wter freezesD onsequently lso the isotope rtio of the ie rystlsD leding to the oserved ehvior with dip in the isotope rtio in the eginning of the experimentF pigure VFIU shows mesurementD in whih ewsEsso ws onneted ehind the gsF sn ddition to the expnsion experimentD the eshe ir efore nd fter the pumpEdown hs een mesured with ewsEsso diretly onneted to the eshe hmer vi heted tuingF hese two dt sets serve s n dditionl lirtion of the mesurement nd llow ompring diretly the isotopi ompositions through the gs nd inside the hmer irF sn the top pnels of (gure VFIUD the wter onentrtion mesurements re shown with kE F @idtFA Y QinD hF @idtFA Y ManningD wF @idtFA Y ChenD F @idtFA Y MarquisD wF @idtFA Y AverytD uFfF @idtFA Y TignorD wF @idtFA Y MillerD rFvF @idtFAX V drop (t + ∆t) = V drop (t) + (Φ 0 (t) -Φ e (t)) • ∆t @fFWA A s (t + ∆t) = π r 2 0 + h 2 (V drop (t + ∆t); r 0 ) @fFIHA for the droplet volume nd the exposed surfe re of the dropletF por the study of the isotopi ehviorD we hve to di'erentite etween the two volumes V C nd V S of the dropletF he hnge of the surfe volume V S is determined y the )ow from the ore volume @Φ C A nd the evportion )ow Φ e X V S (t + ∆t) = V S (t) + (Φ C (t) -Φ e (t)) • ∆t @fFIIA he ore volume is determined y the supply )ow from the syringe pump Φ 0 (t) nd the )ow Φ C (t) to the surfe lyerX

determintion ∆[H 2 O] total mesured y eeGwfGewsEsso ∆[H 2 O] gas mesured y eiGEeiGsyEei ∆[H 2 O] pump = [H 2 O] • (p+∆p)T p(T +∆T ) -1 ∆[H 2 O] ice = [H 2 O] total -[H 2 O] gas ∆[H 2 O] wall = ∆[H 2 O] total -∆[H 2 O] pump R(t) gas mesured y grsEsGsyEei R(t) total mesured y ieEsso R v,wall onstFD free (t prmeter R pump = R(t) gas R ice = α(T ) • α gas α(T ) = α 0 + α 1 T α 0 onstFD free (t
V C (t + ∆t) = V C (t) + (Φ 0 -Φ C ) • ∆t @fFIPA
Very high nesse optical-feedback cavity-enhanced absorption spectrometer for low concentration water vapor isotope analyses eprodution of n yptis vetter VR in the formtting of the thesisF http://www.opticsinfobase.org/ol/abstract.cfm?uri=ol-39-7-1795 © 2014 Optical Society of America. One print or electronic copy may be made for personal use only.

Systematic reproduction and distribution, duplication of any material in this chapter for a fee or for commercial purposes, or modications of the content of this chapter are prohibited.

J. Landsberg, D. Romanini, and E. Kerstel So far, cavity-enhanced absorption spectroscopy (CEAS) has been based on optical cavities with a high nesse F that, however, has been limited by mirror reectivity and by cavity transmission considerations to a few times 10,000. Here, we demonstrate a compact near-infrared optical-feedback CEAS instrument for water vapor isotope ratio measurements, with F > 140, 000. We show that this very high nesse can be eectively exploited to improve the detection sensitivity to the full extent predicted by the increased eective path length to reach a noise equivalent absorption sensitivity of 5.7 × 10 -11 cm -1 Hz -1/2 for a full spectrum registration (including possible eects of interference fringes and t model inadequacies).

sn reent yersD gs onentrtion nd isotope rtio nlyzers sed on nerEinfrredD vityE enhned sorption @gieY hrterized y mesurement of the light intensity trnsmitE ted y the vityA or vity ringdown spetrosopies @ghY hrterized y timeEresolved mesurement of the light intensity deyA hve experiened n inrese in eptne y the sienti( ommunity UIF gompred with their onventionl mss spetrometer ounterprtsD optil instruments re esier to hndle nd enle ontinuous nd in situ mesurements with high temporl resolutionF ergulyD wter vpor isotope mesurements hve ene(ted the mostD s evidened yD eFgFD IHD UVD IUQF roweverD there is numer of pplitions for whih higher detetion sensitivity is imperE tiveF por exmpleD some of the most interesting isotopi proesses involving tmospheri wter our t wter undnes well elow the rnge essile with ommonly ville lser speE trometersF sn the entrti tmosphereD wter onentrtion does not normlly exeed few hundred prts per million y volume @ppmvAD wheres in the lower strtosphere it rehes lows of just few ppmvF ssotope studies in these environments re relevnt for the vlidtion of the @gFIA yne possile wy to inrese the sensitivity of gie spetrometer is to omine it with highEfrequeny modultion tehnique in order to redue δIF his is exploited in noiseEimmune vityEenhned optil heterodyne moleulr spetrosopy @xsgiEyrwA whihD howeverD is experimentlly highly omplex VHF sn dditionD its full sensitivity potentil hs never een pprohed in pplitions where omplete hopplerErodened rovirtionl fetures need to e reorded IUUF e ompelling lterntive is to simply inrese L e y inresing the (nesse F of the optil vity through the use of very highEre)etivity mirror otingsF here re two ovious disdvntges to this pprohF pirstD the time required to reh the full uildEup of light intensity inside the vityD s well s the susequent dey of the light leking out of the vity @τ AD re lso proportionl to FF his inreses the time required to reord the spetrumD thus lowering wF eondD higher (nesse tends to redue the deteted signl y reduing the oupling e0ieny of the reltively rod lser emission @the freeErunning linewidth of hpf lser s used in this study is severl wrz on I s timesleA to the exeedingly nrE row vity mode width @∼ I krz for the highE(nesse vityAF sn dditionD n inrese of the mirror re)etivity is lmost inevitly ompnied y redution of the mirror trnsmission @s there is tehnil lower limit to the losses used y oting sorption nd stteringA whih redues the vity throughput t resonne UIF husD for norml gie or gh one expets to gin sensitivity proportionl to (nesse due to use of lower vity trnsmissionD either proportionl to FD when the system is limited y detetor noiseD or y F in the se of shotEnoise limited detetionF vonger verging my ompenste for slower spetrum quisitionF roweverD the mximum verging time isD in ll prtil situtionsD determined y vritions in environmentl ftors tht limit the stility time of the spetrometer @T opt D s determinedD eFgFD y the minimum in n ellnEerle plot WVAF feyond this timeD drift will strt degrding the detetion limitF woreoverD mny systems re not limited y tehnil noise ut rther y optil interferene fringes @etloningA whih my not e eqully suseptile to vergingF )uoroliphti polymer @gytonix pluoroel VHHeAF eir inside the instrument housing is ventiE lted nd regulted to 38 ± 0.1°g with thermoEeletri irEir het exhnger @uperoolAF he temperture of the optil redord is stilized t RS°g using dhesive heter tpes @winoAD regulted with proportionlEintegrlEdi'erentil feedkEloop implemented in softwreF he smple pressure inside the vity is regulted to QS mr y ustom iltekEtreted @estekA pressure ontroller @fronkhorstA t )ow rte of ISH stndrd mvGmin for lulted gs exE hnge time of HFQS sF yver period of QFT hD the drift of the vity temperture is smller thn HFS mu nd the drift of the pressure smller thn IH µrD s mesured with sensors not used in the ontrol loopsF he signl nd referene photodiode outputs re digitized y P hnnelD IT it eGh onverter with reord length of THk points nd V µs step size @IPS krzAF xote thtD ompred to the previous spetrometerD out R times s mny dtpoints re quired per spetrl snD while the detetor ndwidth @RV krzA is mthed to the xyquist limit ssoited with the dt quisition rteD enling n improved de(nition of the vity trnsmission signlF sn view of the long vity ringEdown timeD the snning frequeny is set to P spetr per seond @∼IH for ssA nd the lser tuning speed to one vity p @ISQFP wrzA in QFS ms @∼HFS ms IUU for ss TAF e single spetrum spns out IIH suessive vity modesD orresponding to spetrl window of HFT m -1 F et the end of eh snD the lser is interrupted for QFP ms in order to reord ringEdown event on the lst vity mode with typil shotEtoEshot w frtionl vrition of 1.7 × 10 -4 F his mesurement llows for n solute lirtion of the sorption sle TD VIF por the nlysisD spetrum omposed of utin line pro(les WQ is (t to eh individul retrieved spetrumD nd the isotope rtios re lulted using the integrted line intensities T efore eing vergedF esorption lines of methne in the sme spetrl region re introdued in the (t sine methne sorption eomes n importnt ftor t wter onentrtions elow ∼SHH ppmvF he seline is (t y two strong wter sorption lines outside the mesurement rngeD whih re grouped with the r 2 16 y lines inside the mesurement rngeD nd n dditionl thirdEorder polynomilF o determine the preision of the isotope rtio mesurementsD gs ottle ws repetedly pigure gFPX ime series of r 2 16 y nd its isotope rtios @two top pnelsA nd the orresponding elln plots @ottom pnelA for the seleted dt for r 2 18 yD r 2 17 yD nd rh 16 yD s well s the deuteriumE nd 17 yEexessesD s funtion of verging time T t wter mixing rtio of PH ppmvF prepred with mixture of dry syntheti ir nd lol wter stndrd for di'erent wter onentrtionsF his stndrd gs ottle ws then onneted to the ypEgie instrument for longterm stility mesurements @bV hAF revious studies ompring this method with mirodroplet injetor indite tht isotopi frtiontion using stndrd SH v tnk is undeE C. Optics Letter stility of rips is thus muh higher thn tht of ssD for whih the longest optimum integrE tion time ws ∼S min IIVD mostly due to the etter temperture stiliztion @fF hpter QAF he est preision for δ 2 r nd δ 17 y is otined t round ISHH ppmvF por δ 2 rD UH min vergE ing gives preision σ( 2 H) = 0.12 D while verging of Q min results in σ( 17 O) = 0.07 nd σ( 18 O) = 0.05 F roweverD the optimum for δ 18 yD with σ( 18 O) = 0.02 D is otined t lower wter onentrtion of ∼THH ppmv @in out QH minAF sn ftD vity trnsmission t the pek of the r 2 18 y sorption line drops to IH7 t ISHH ppmvD giving signlEtoEnoise rtio fr from optimlF sn tle gFID the preisions t di'erent wter onentrtions re given for T = 4 s @V dt pointsA verging nd for the elln optimum σ(T opt )F ith R s vergingD the time resolution is still su0ient to study fst isotopi proessesD ut the preision is nerly ftor of three etter thn for nonverged @HFS sA mesurementsF sn onlusionD the new instrument hieves similr or etter results in terms of mesurement preision ompred to our previous ypgie wter isotope spetrometerD s well s ompred to most ommeril wter vpor spetrometers ut t wter onentrtion tht is pproximtely n order of mgnitude lowerF he xie of 5.7×10 -11 m -1 rz -1/2 @or 5.4×10 -12 m -1 rz -1/2 when normlized per spetrl elementA is mong the lowest vlues reported for nerEinfrred gie so frD with the exeption of xsgiEyrw @with its muh smller tuning rngeA nd the lowest for gie with se length elow SH mF rereD the instrument o'ers the possiility to reord useful isotopi signls in dry entrti or upper tropospheri ir nd eventully even in strtospheri irF he improved stility time n e used to inrese the preision on sinE gle mesurement efore drift strts dominting the noiseF st lso enles longer uninterrupted reording efore relirtion needs to e rried out WVF he instrument is ple of even higher preision or higher sensitivity isotopi mesurementsD when only one or two isotopi rtios need to e determinedF sn previously identi(ed rnge round 7200 m -1 IUWD the spetrl lines re etter seprted nd the isotopologuesD exluding δ 17 yD n e mesured with modestly etter preisionF elterntivelyD we reently demonstrted IUW tht ner 7286 m -1 D δ 18 y n e mesured lmost one order of mgnitude etter with minE iml elln devition of HFR7 in QH min t only R ppmv r 2 16 y @fF hpter VAF fy temperture tuning of the sme lserD it is lso possile to mesure δ 2 r t 7289 or 7280 m -1 D with ompE rle performne to wht is shown here t 7184 m -1 F pinllyD nery r 2 16 y lines t 7299.43 nd 7181.17 m -1 my e used for wter detetion elow HFI ppvF ispeilly in the se of moleule in whih @nhrmoniA hydrogen osilltor is exitedD suh s wterD our pproh my void the need to use more omplex ws light soures nd optisD given tht line strengths my di'er y only one order of mgnitudeD esily ompensted y the higher (nesse ville in the xsF

Friday

  Book cover: weike ulosterEvndserg nd pelix tnek vndsergX fkground photoX view from the slope of tutulhogget ner roll sttionD entrti pront @left to rightAX r 2 16 y ehvior during n ie loud formtion in the eshe loud hmerD the interior of the ypEgie instrument ssD droplet formtion on the tip of syringe fk @left to rightAX en eletroni rd of the ypEgie instrumentD roll sttionD min uildingD uler lirtion setEup sfx @iEookAX WUVEWHEQTUEURRUES sfx @ookAX WUVEWHEQTUEURRVEP ulished y mrtrinting solutions E httpXGGspsEprintFeu E Gouda, The Netherlands he work presented in this thesis reeived support fromX xetherlnds yrgniztion for ienti( eserh @xyA under projet numer xee VSIFPHFHHRS niversity of qrenole instlltion funding iF uerstel edditionl funding from q resoures xpD hpq qis nd iygrewEP @sygvyh mpignA xorwegin olr snstitute @logistis roll mpignA Development of an OF-CEAS laser spectrometer for water vapor isotope measurements at low water concentration PhD thesis to obtain the degree of PhD at the University of Groningen on the authority of the Rector Magnicus Prof. E. Sterken and in accordance with the decision by the College of Deans.This thesis will be defended in public on

2. 2

 2 The optical alternative: Stable Isotope Ratio Infrared Spectroscopy en lterntive for the mesurement of wter vpor isotope rtios is o'ered y di'erent optil mesurement tehniquesF sn the nerE nd midEinfrred region of the eletroEmgneti spetrumD the di'erent wter isotopes show numer of highly hrteristi rottionlEvirtionl trnE sitions @(gure PFIAF sf the vpor nd totl pressure re su0iently lowD the individul moleulr trnsitions n e esily resolved nd ttriuted to spei( wter isotopologueF pigure PFIX imulted sorption spetrum of wter in the infrredD sed on the rsexPHIP dtse TIF he width of the individul roEvirtionl trnsitions re too smll to e visile on this sleF he simplest method to nlyze gs smpleD is diret sorption spetrosopyF e light em with intensity I 0 nd frequeny ν 0 tht psses through n sorption ell of length lD (lled with n soring medium of onentrtion c experienes n ttenution of the intensity due to light sorption y the gs moleulesF his ttenution is desried y the vmertEfeer vwD whih is vlid in the liner sorption regimeX I = I 0 exp(-α(ν)l) @PFIA he dimension of I nd I 0 is power per unit reF he frequeny dependent sorption oe0ient α(ν) n e lulted y α(ν) = σ(ν)n @PFPA with n the moleulr numer density nd σ(ν) the moleulr ross setionD whih depends on the frequeny ν through the line pro(le funtion g

  T 0 ) the line strength t referene temperture T 0 uelvinD nd E nd E the lower nd upper stte energyD respetivelyF k is foltzmnn9s onstnt nd Q(T ) the roEvirtionl prtition funtion of the moleuleD whih n e pproximted y temperture dependent third order polynomil TQF he penultimte term ounts for the rtio of foltzmnn popuE ltionsD wheres the lst term desries the e'et of stimulted emissionD whih in the infrred n usully e negletedF iqution PFS ssumes stti gs ell with onstnt numer densityF et onstnt pressure insted of onstnt volumeD the right hnd side of eqution @PFSA hs to e extended with the term T 0 /T D whih is proportionl to the numer densityF his is the usul se for the spetrometer of this thesisD in whih the gs )ows through the gs ell t onstnt pressureF hepending on how the sorption oe0ient is de(nedD the line strength S is expressed in difE ferent unitsF e onvenient hoieD nd the one used for the rsex dtseD is to express the line strength S in mGmoleuleD the numer density in moleulesGm 3 D the optil pth length in mD nd the width of the optil trnsition in wvenumers @m -1 AF elthough the sorption of light y moleule hppens t well de(ned frequeniesD the sorption is not in(nitely nrrow ut tkes ple in frequeny rnge round these entrl frequenies due to di'erent rodening mehnismsF his results in line shpe of eh spetrl lineD whih is desried y the ove mentioned line pro(le funtion g(ν -ν 0 ) nd tkes into ount di'erent physil phenomen tht ontriute to the spetrl rodeningF IT 2. Measurement of isotopes 2.3 Optical Spectroscopy Techniques hi'erent optil tehniques hve een developed for spetrosopi mesurementsD of whih we will introdue some of the most importnt in the followingF e tehnique tht exploits the feerEvmert lwD is diret sorption spetrosopy SD UD TR!TTD lso termed unle hiode vser esorption petrosopy @hveA when the lser in question is either ledEslt or semiondutor diode lserF sn order to inrese the sensitivity of this methodD while mintining smll footprint of the spetrometerD the optil pth n e folded etween two refousing mirrorsD reting multipleEpss ell @wgAF hi'erent on(gurtions hve een developed over the yersD the most ommon of whih re the hite ell TUD TV nd the rerriot ell SD TRD TWF he wvelength of the lser is tuned over one or severl sorption lines y hnge of the lser urrent so tht their sorption pro(le n e mesured y registering derese in the trnsmitted light levelF en lterntive spetrosopi method o'ering muh lrger e'etive pth lengths is gvity ing hown petrosopy @ghAD whih is sed on the mesurement of the dey rte of light injeted into n optil vity formed y two or more high re)etivity mirrorsF sn the followingD we give short nd simpli(ed introdution to ghD more detiled nd re(ned piture n e found for exmple in UHD UIF hen light is injeted into the vityD it trvels k nd forth etween the mirrorsF et eh re)etion on one of the vity mirrorsD the intensity of the light splits into three prtsF he lrgest prt is re)eted k into the vityD whih is expressed with the e)etne R of the mirrors @presentEdy vity mirrors typilly hve vlues of R > 0.99AF enother prt is trnsmitted through the mirrorD desried y the rnsmittne T nd the remining prt is lost due to sorptions nd sttering in the mirror itself @the voss LAF feuse of energy onservtionD the reltion etween RD T nd L isXR + T + L = 1 @PFTAhe intensity of the light trnsmitted through the optil vity n e mesured with phoE todetetor ehind one of the vity mirrorsF sf the light injetion is interruptedD either euse pulsed lser is used or euse of n interruption of ontinuous wve @gA light soureD the trnsmitted light intensity shows n exponentil ehviorXI(t) = I 0 e -t τhe soElled ingEhown @hA time τ does not depend on the mplitude of the light pulse nd is thus not 'eted y intensity )ututions of the light soureF sn the following we will give simplisti desription of the gh in the soElled rodEnd or llisti pprohF vter we will orret the results otined in this mnner suh tht they n e pplied to our se of g nrrowEnd exittion of the vityF e more omplete desription n e found in UIF efter 2.3. Optical Spectroscopy Techniques IU pigure PFPX ingEpong or llisti model of pulsed ghX short lser pulse is injeted into vityF et eh re)etionD only portion of the light is re)etedD while nother portion is trnsmitted nd prt is lost due to sorption in the smple ell nd in the mirrorF his leds to n exponentil derese of the trnsmitted signlD mesured y photodiode ehind the vity @(gure sed on grph from UPA (rst pssge through the vityD the initil intensity I in is ttenuted toX I 0 = T 2 e -αl I in @PFUA with α the sorption oe0ient of the soring medium in the vityF efter n round tripsD the intensity mesured y photodetetor n e lulted withX I(t) = I 0 e -2n(-ln R+αl) @PFVA e n now reple the disrete numer of psses n y the time the light spends in the resontorD t = 2 • l • n/cD whih rings eqution PFV to ontinuous formX

  sn gieD lser light is oupled into the vity nd the intensity of the light leking out of the vity is detetedF he frequeny of the lser should e in resonne with one of the vity modesF snsted of following the dey of the light in the vity in rel timeD the temporl inteE grtion of the totl trnsmitted intensityD whih depends on the ttenution of the light trpped within the vity y n soring smpleD is mesuredF feuse of the ontinuous mesurementD no rpid interruption of the lser is requiredF he lrgest hllenge in this tehnique is to otin high e0ieny of injetion of the lser into the vityF et higher (nesse of n optil vityD the trnsmission mode envelope of the vity eomes nrrower nd the injetion of the light into the vity eomes more di0ultF

  eomes mjor prolem when using very high (nesse vitiesD in whih the oupling is even more di0ult euse of the orrespondingly nrrower vity mode widthF sn the se of ypEgieD portion of the light @optil feedkA trvelling inside the vity is send k to the lser soureD whih results in oupling of the lser to one of the vity modesD whih in turn leds to nrrowing of the lser line width to elow tht of the vity mode trnsmission VIF pigure PFSX hemtis of typil ypEgie setEup with Eshped vity @(gure from VP e shemti of typil ypEgie setEup with Eshped vity is shown in (gure PFSF he light from diode lser is injeted into Eshped vity vi set of di'erent optil omE ponentsF he Eshpe of the vity e0iently voids tht diret re)etion from the folding PR

2. 6

 6 Absorption scale linearity es mentioned oveD in diret sorption tehniquesD the moleulr sorption oe0ient α is otined in very strightforwrd mnner from the vmertEfeerEfouguer lwX I t the trnsmitted intensityD I 0 the inoming light intensity nd l the e'etive pth lengthF sn the se of ypEgieD the reltion etween moleulr sorption nd intensity is more omE plitedF es desried in detil in TD VI nd rie)y summrized in the followingD the reltion etween α nd the trnsmitted intensity in ypEgie llows the mesurement of isotope rtios over muh lrger onentrtion rnge thn in diret sorption spetrosopyF sn the se of Eshped vity with vity rm lengths l 1 nd l 2 D (lled with n sorer with sorption oe0ient α m = α(ω m ) t the enter of vity modeD the vity trnsmission is desried with n eiryEshped trnsfer funtion whose mximum t frequeny ω m is given y VPX

  vrines of temperture nd pressure in the instrumentF he sensors used for the elln vrines re independent sensors nd not used for the regultionF he stility of the ell temperture is etter thn I muD the mximum t I s is due to the redEout of the sensorF he pressure is regulted with preision of etter thn IH µr over time of QFT h 3.6 Choice of spectral ranges hepending on the spei( requirements of the mesurementsD di'erent spetrl regions in the ner infrEred were seleted for the mesurementsF por most of the mesurementsD spetrl region round UIVR m -1 ws hosen tht ws lso used in previous instruments TD VQ nd is lso used y ommeril instruments UVD VTF es n e seen in n exemplry spetr in this

  of spetr t A UPVT m -1 nd A UPVH m -1 D respetivelyF petrl informtion from the ritrn dtse TIF Chapter 4Data analysis procedures o retrieve onentrtions nd isotope rtios from mesurementD theoretil model is genE erlly (t to the experimentl spetrF por the syntheti spetrD di'erent models n e usedD tht tke di'erent ftors responsile for line rodening into ountF sf the pressure of the gs smple is very low @p ≤ 0.5 mrAD the line width of the spetrl lines is dominted y the hoppler line widthF st tkes into ount the e'et tht the frequeny t whih moleule with veloity omponent long the trjetory of the light em sors nd emits eletromgneti rdition is slightly shiftedF es the veloity of the moleules in gs is due to therml motionD this hnge in the sorption frequeny leds to qussin line shpe VVX

QW 4 . 1

 41 Analysis of experimental spectra por the nlysis of our experimentl spetrD simulted spetrum sed on the utin line pro(le is (t to the experimentl dtF he line positions of the di'erent sorption lines were tken from determintions with high sensitivity gEgvity ing hown petrosopy done y veshhishin et lF WS nd the frequeny sle of the mesured spetrum ws sled linerly to mth this theoretil spetrumD e'etively determining the p of our ypEgie vityF he qussin line widths @hoppler rodeningA were lulted for the di'erent isotopologues sed on the gs ell temperture nd then (xed for ll spetrF vorentzin widths @pressure rodeningA nd the hike prmeters @motionl nrrowingA were (t one over n exemplry mesurement nd kept onstnt throughout the mesurementsF he reltive intensities of di'erE ent sorption lines from the sme isotopologue were (xedD thus yielding only one free prmeter for intensity per isotopologueF xote tht of di'erent temperture dependenies of the strengths of di'erent sorption linesD this grouping should only e done with very good temperture stiliztionD whih is present in our spetrometerF sn ddition to the group intensities for eh isotopologueD n dditionl prmeter ounts for possile mode shift of the entire spetrD whih n our due to smll temperture )ututions of the gs or gs ell tempertureF o tke into ount dditionl sorption lines of methne in the sme spetrl regionD these lines were introdued s n dditionl speies in the model spetrumD with n dditionl (tted group intensity prmeterF he sorption frequenies of methne were tken from mesurements of gmprgue et lF WTD wheres we determined the reltive intensities nd vorentzin line widths of the strongest methne sorption lines in mesurement on diluted methne smpleF he methne sorption does not ply n importnt role for higher wter onentrtions ut eE omes n importnt ftor t lower wter onentrtions @SHH ppmv nd elowAF he seline is (t with neighoring strong wter sorption lines outside the mesurement rngeD nd n dditionl third order polynomilF he qulity of the (tD nd onsequentilly n importnt ftor of the instrumentl performneD is determined y the residul on the (tF hroughout the wter onentrtion rngeD in whih we n mesure with ssD the w of the residul on the (t is elow 8 × 10 -11 m -1 @t P rz mesurementsAF et wter onentrtions elow SHH ppmvD the xie of the instrument is typilly round 6 × 10 -11 m -1 rz -1/2 D whih is n improvement y ftor of lmost U ompred to the predeessor instrument ssF 4.2 Precision sn the se of n solutely stle systemD the preision of the mesurements would ontinuE ously improve with inresing integrtion timeF roweverD in the rel world instrument stility is limitedD for exmple euse of temperture or pressure drift or mehnil disturnesF pigure RFIX e single experimentl spetrumD reorded in HFSI s t SHH ppmv r 2 yF he w of the residul @ottom pnelAD is 8 × 10 -11 m -1 feuse of these driftsD longer verging is only ene(il up to the level where instrumentl drift eomes notieleF he optimum integrtion time n e e'etively determined with n ellnEerleEplotF he ellnEerleEplot ws (rst introdued to the (eld of lserEsed tre gs detetion to revel low frequeny drift phenomen WU nd lter dpted to hrterize instrumentl stility WVF o determine the stility of ss nd its level of preisionD long time mesurements t di'erent wter onentrtions were mdeF e gs ottle ws (lled with mixture of dry syntheti ir nd lulted mount of lol wter stndrd to given wter onentrtionF his stndrd gs ottle ws then onneted to the ypEgie instrument for long time @b VhA stility mesureE mentsF his mesurement ws repeted with di'erent wter onentrtions in the rnge from PH ppmv to ISHH ppmvF wesurements with ottle (lled with stndrd wter gs mixture is well dpted pproh for long term stility mesurements s it o'ers very stle moist ir supply nd is very esy to useF wost importntlyD uerstel et lF T showed tht frtiontion in the ottle n e negleted under the onditions enountered in our experimentsD with prtil pressures well elow sturtionF pigure RFP shows ellnEerle plots for the isotope rtios of the three isotopologues rhyD r 2 17 y nd r 2 18 y from mesurements t di'erent wter onentrtions tht were done with stndrd gs ottles s desried oveF sn the se of δ 2 rD the est preision σ opt = 0.12 is rehed in τ opt = 36.4 min nd t wter onentrtion of ISHH ppmvF por δ 18 y the optimum integrtion time is lso τ opt = 36 minD 4.2. Precision RI ut the est preision is t r 2 y= 600 ppmv nd for δ 17 y the est results re hieved with τ opt = 70 min t ISHH ppmv nd σ opt = 0.064 F feuse of fst nturl isotope vritionsD it is not lwys possile to integrte the mesurements for more thn QH minF feuse of thisD the preision tht n e hieved in shorter time is lso very importnt mesureF sn tle RFID the preisions t the di'erent wter onentrtion mesurements shown in (gure RFPD re given for T = 4 s @V dt pointsA verging nd for the elln optimum integrtion time T opt F ith R s vergingD the time resolution is still su0ient to study fst isotopi proessesD ut the preision is nerly ftor of three etter thn for nonEverged @HFS sA mesurementsF es n e seen in devition for the three isotopes (gure RFQD the preision of the mesurements in wter onentrtion rnge from 200ppmv to 2000ppmv remins pproximtely the sme for ll three isotopologuesF por δ 2 rD the preision is lwys etter thn 0.8 D for δ 17 y etter thn 0.15 nd for δ 18 y etter thn 0.1 F e deE tiled disussion of the preision of our instrument n e found in VRD whih is inluded in the ppendix of this thesisF sn the letterD the instrument is nmed ripi @righ pinesse snstrumentA to void onfusion with the nme of the previous instrument ssF RP 4. Data analysis procedures pigure RFQX winimum elln devition vsF rPy le RFIX wesurement reision s puntion of the ter wixing tio for hi'erent everE ging imes

  performne of the (tting routine used to nlyze our dt nd to investigte ftors tht n in)uene the nlysis of the dtD syntheti spetr were generted with vview sed simultion progrmF por the simultionD the gEsed routine tht is lso used for the (tting nlysis of the dt ws inorported into the vview progrmF ell generted spetr were simulted with utin line pro(leF qussin nd vorentzin widths s well s the hike prmeter were set to the verge vlues tht were otined from (ts to experimentl spetrF he reltive intensities of the di'erent lines of the sme isotopologue were (xedF o simulte hnges in the wter onentrtion onlyD the intensities of ll spetrl lines of wter were eqully sledF he seline of the simulted spetr onsists of seond order polynomilD superimposed with qussin white noiseF o ompre syntheti nd experimentl dtD simultions were done with qussin noise of the sme size s the (t residul of the experimentl spetr nd the intensity of the spetrl lines ws lso mthedF sn (gure RFRD the ellnEerle plot of n experimentl run t VH ppmv r 2 y with residul of 7.1 • 10 -11 m -1 is shown together with tht of syntheti dt simulting the sme onditionsF urprisinglyD the experimentl dt yield n elln devition tht is more thn two times lower thn of the syntheti dtF e histogrm over the residuls of QH susequent spetr of the mesurement used for the ellnEerle plot @(gure RFSA shows tht the experimentl noise is indeed qussin distriutedD s would e expeted for unorreltedD normlly distriuted white noiseF ith pure white noiseD verging of severl spetr redues the residul of the (t @σ avg A with the squre root of the numer of verged spetr @xAX

4. 4

 4 Photodetector linearity e possile prolem tht is well known in spetrosopi studies is photo detetor nonElinerity IHHD IHID tht isD the signl voltge hs nonliner dependeny on the inident powerF e nonElinerity would hve lrge e'ets on our mesurementsD s hnge of the emitted lser power would result in n pprent hnge of the wter onentrtion nd of the pprent isotope rtiosD s ws shown y uerstel et lF IHPF 4

  1 × 10 -9 nd results in ringEdown time of τ = 119.41 ± 0.03 µsF he oe0ient of the nonElinerity term = (-1.8 ± 6.0) × 10 -3 nd thus is equl to zero within the error limitsF sn oth (guresD the ringEdown event is shown on logrithmi vertil sleF he urve devites from stright line for lower signls euse of the nonEzero kground signl of the photo detetorF es n ordinry exponentil funtion mthes the ringEdown event very well nd the dditionl qudrti term is within the error equl to zeroD it n e onluded tht the photo detetors show nonElinerity tht is well elow the mesurement preision of the instrumentD nd the onentrtion nd isotope rtio mesurements re not 'etedF 4.5 Power saturation wesurements with the ypEgie tehnique rely on the liner dependene of the sored power on the inident lser intensityF roweverD if the popultion density of the soring level is notiely diminished due to the sorption of lser rditionD sturtion of the trnsition n our nd the reltion of sored power nd inident intensity is no longer purely linerF turtion of trnsition is rehed when the depletion of level due to relxtion eomes omprle to the sorption indued popultion of the sme levelD tht isD the numer of moleules tht re exited from the ground stte to n upper stte is omprle to the numer of moleules tht go k to the ground level URF e lrger lser power leds to stronger depletion of the ground level of trnsitionD wheres lrger numer of moleules in the gs ell @higher pressureA results in ollision indued relxtion of the upper levelF he intensity t (a) (b) pigure RFIHX en verge of QH ringEdown eventsD (t with A n ordinry exponentil dey nd A ssuming nonElinerity of the photo detetorsF xote tht the ringEdown signl devites from stright line in the logrithmi plot t the end of the mesurementF his is due to the detetor kgroundD whih is lrger thn zeroF SI whih sturtion of trnsition ours n e lulted with IHQ

  moleulesF his eomes importnt if di'erent rrier gses re to e used in the experimentsF he vorentzin widths of the spetrl lines depend on the u'er gs tht is used nd di'erent prmeter (le for the spetrl (t hs to e used for eh of the gsesF feuse of thisD di'erent rrier gses for lirtion nd mesurement hve to e voidedD nd if possile preisely the sme reltive undnes of di'erent moleules should e usedF wo mesurements under extly the sme onditions ut with di'erent rrier gses re shown pigure RFIPX gomprison of two experimentl spetr mesured t the sme onditions ut with di'erent rrier gsesF sn lk mesurement in ir is shown nd in redD mesurement in nitrogenF he di'erene etween the two spetr is given in green @right sleAF in (gure RFIPF por the two mesurementsD syntheti ir @PH7 oxygenD VH7 nitrogenAD nd pure SR 4. Data analysis procedures nitrogenD respetively were used s rrier gsesF

  nd s for isotope stndrd I nd PD nd the unknown smpleD respetivelyD nd the suE persripts (m)D (cal) nd (t) inditing mesuredD lirted nd true isotope delt @determined independentlyD eFgF y sw mesurementsAF sn mny optil spetrometersD howeverD the isotope rtios of the sme smpleD mesured t di'erent onentrtionsD re dependent on the onentrtion t whih they re mesured IHW! IIQF elthough the mesurement should result in the sme isotope rtioD independent of the onentrtion t whih it ws mesuredD this is often not the se nd n dditionl orretion of the isotope mesurements for the onentrtion hs to e mdeF he reson for the onentrtion dependene of the isotope rtios is not lwys evident nd often hs di'erent resons in di'erent instrumentsF irly mesurements with the olor enter lserD dul gs ellD liquid wter isotope rtio spetrometer developed in the midEWH9s t the uniE versity of qroningen required orretion for the di'erene in the mount of wter injeted into the referene nd smple gs ellsF his e'et ws understood s due to di'erentil pressure rodening etween the smple nd referene ellsD nd ould e quntittively desried with simple model TRF uzson et lF IHW propose mongst other things instrumentl nonElinerityD nonEunity gin ftors nd potentil rossEoupling e'ets s potentil resonsF grossEoupling etween di'erE ent spetrl lines in the mesurement euse of overlpping wings of the sorption linesD n e very pronouned in spetr with mny di'erent sorption linesD where the seprtion of the individul lines is not lwys strightforwrdF edditionl soures n e unertinties in SV 5. Data Corrections and Calibration the spetrl seline nd the tils of very strong sorption lines tht re lose to the spetrl window used for the mesurementsF sn the se of our instrumentD strong r 2 16 y sorption lines lose to the spetrl region used pigure SFIX ter @lueA nd methne @greenA spetr mesured t UIVR m -1 F he mesureE ment of r 2 y ws done t QSH ppmv nd the gr 4 mesurement t n enhned onentrtion of pproxF IUHH ppmv to lolize dditionl methne sorption lines in the spetrl rnge meE sured with our instrumentF o improve the result of our dt (ttingD the di'erent sorption lines were inluded into the model spetr (t to our dtF et nturl undne @`P ppmvA the methne peks re generlly not visile in the spetrumF for the mesurements re tken into ount in the model spetr (t to the experimentl dtF purthermoreD dditionl mesurements in the spetrl region were mde on wethne smples t n enhned onentrtion of pproxF IUHH ppmvD to tke weker wethne sorption lines into ount s well @fF (gure SFIAF hese sorption lines re t nturl undnes @`P ppmvA generlly hidden in the wter sorption spetrF efter reful genertion of the model spetr nd di'erent (t pprohesD we found tht the min soure for the remining onentrtion dependene of the isotope rtios is strutured nd timeEinvrint noise in the mesurementD disussed in more detil in setion RFQF sn (gure SFPD the isotope rtio mesurements s funtion of the wter onentrtion re shown for two syntheti dt setsD whih were simulted s desried in setion RFQF foth simultions were done with n w of the residul of 7.8 × 10 -11 m -1 nd the onentrtion of the di'erent isotopes ws vried y hnging the mplitudes of the individul spetrl linesF he reltive hnge of ll mplitudes ws identilD suh tht the isotope rtios should remin onstntF sn one simultionD the noise ws qussin white noise onlyD whih ws relulted with fresh strt of the rndom numer genertor for eh spetrumF sn the other simultionD VQ7ws timeEinvrint strutured noise s previously oserved in the mesurementsF heres the isotope rtios in the mesurement with white noise only @(gure SFPD in redA show lmost no vrition with hnging wter onentrtionD the mesurement with strutured noise @in lkAD shows strong dependene of the isotope rtios on the wter onentrtionF et very low wter SW of the isotope rtios of two syntheti dt sets with vrying wter onentrtionsF A δ 2 rD A δ 18 y nd A δ 17 yF sn the se of pure white noise @in redAD the isotope rtios show essentilly no dependene on the wter onentrtion in the mesurementF sn mesurement with VQ7 strutured noise @in lkD see lso setion RFQAD the onentrtion dependene eomes very pronouned for ll three isotopologuesF TH 5. Data Corrections and Calibration onentrtionsD the sorption lines eome weker nd the in)uene of the strutured noise on the mesurement eomes even more pronounedF feuse of thisD the isotope rtios show very lrge devitions for lower wter onentrtions nd lmost no devition for lrger onentrE tionsF of six simultions with TH7 @rndomly genertedA strutured noiseF he pttern of the strutured noise hs lrge in)uene on the onentrtion dependene of the isotope rtioF fetween di'erent simultionsD the onentrtion dependene even hnges the sign euse of the di'erene in the strutured noiseF sn (gure SFQD the isotope delts from the (t of six di'erent simultions with vrying wter onentrtions re shownF he simultions were ll done with TH7 strutured noise nd were identil prt from the strutured noiseD whih ws eh time rndomly generted qussin distriuted noiseF he di'erene in strutured noise results in hnges of the onentrtion dependene of the isotope rtios nd n even led to hnge of the sign of the dependeny etween di'erent simultionsF sf the pttern of strutured noise hngesD the onentrtion deE 5.1. Calibration strategy TI pendene lso hnges nd orretion for the onentrtion dependene eomes very di0ultF sn generl it is thus not possile to ssume timeEinvrint onentrtion dependene of the isotope rtiosF prequent lirtions t di'erent wter onentrtions re neessry to ount for hnges of the noise pttern in the mesurementsF roweverD the extreme se of omplete hnge of the strutured noise ptternD s generted in the simultionsD does normlly not our nd the rel hnges re muh smllerF sn (gE ure SFRD lirtion mesurements over ITEdy period during mesurement mpign re shown for 2 sample G 2 VSMOW nd 18 sample G 18 VSMOW mesurements t UPHH m -1 F feuse of the strong isotopi enrihmentD the vlues re given in rtios insted of permilF es n e seenD the onentrtion dependene only hnges slightly etween di'erent mesurementsD whih mens tht the shpe of the pttern noise stys very similr throughout the entire mesurement mpignF et wter onentrtions round THH ppmvD the w devition from the verge onentrtion dependene is IH for 2 sample G 2 VSMOW nd IFS for 18 sample G 18 VSMOW F et very low r 2 16 y onentrtions round IH ppmvD the w devition inreses to ITH nd QS for 2 sample G 2 VSMOW nd 18 sample G 18 VSMOW D respetivelyF (a) (b) pigure SFRX glirtion mesurements over ITEdy period during mesurement mpignF he isotope rtios re plot versus wter onentrtion for A 2 sample G 2 VSMOW nd A 18 sample G 18 VSMOW F he di'erent olors indite di'erent lirtion mesurementsF he onentrtion dependene remins very similr for ll mesurementsD inditing tht in rel experiments the funtion desriing the dependene remins virtully unhnged over timeF 5.1 Calibration strategy feuse of the onentrtion dependeneD the lirtion of our mesurements hs to e done in two stepsF pirstD the isotope rtios hve to e orreted for the wter onentrtion e'et nd seondD lirtion of mesured versus true delt vlues hs to e rried outF TP 5. Data Corrections and Calibration sn the followingD our lirtion strtegy is illustrted on set of three isotope mesurements done t UIVR m -1 F pirstD mesurement of the isotope stndrd qRV ws done using the xsg lirted wter vpor genertor @see setion TFPA t di'erent wter onentrtion stepsF usequentlyD mesurement with vrying wter onentrtion of the stndrd qPP ws doneD whih serves here s our unknown wter smpleF pinllyD mesurement of qSH s seond lirtion stndrd ws done t di'erent wter onentrtionsF his sequene enles us to lirte the mesured vlues for the unknown qPP smple on the isotopi sle de(ned y the lol stndrd mterils qRV nd qSHD whose isotopi ompositions rket tht of qPPF his is thus similr to the seieEreommended proedure for lirtion to the wyEve sle @see eginning of this hpterAF yver eh onentrtion step of the mesurementsD the verge of the wter onentrtion nd the isotope rtios ws lultedF es n exmpleD we show the mesurement of qPP in (gure SFS for @A wter onentrtion nd @A isotope deltsF por eh onentrtion stepD unstle periods were exludedF he light gry oxes in the (gure indite the setions over whih verges were lultedF (a) (b) pigure SFSX wesurement of wter onentrtion vrition of the stndrd qPP generted with xsgF he light gry oxes indite setions over whih verges were lulted for the lirtionF sn (gure SFTD the verge delt vlues re plot ginst the wter onentrtion for @A δ 2 rD @A δ 18 y nd @A δ 17 yD lerly showing the dependeny on the mount of wter in the mesureE mentsF heres the reltion is lmost liner for lrger wter onentrtionsD it is nonEliner for onentrtions elow ISH ppmvF e found tht the onentrtion dependene is est desried with liner term in omintion with hyperolX δ([r 2 16 y]) = δ 0 + m × [r

  he djusted isotope rtios re shown in (gure SFV for ll three isotopologuesF he orretion results in delt vlues tht show no longer dependeny on the wter onentrtionF por very low wter onentrtions @`SH ppmvAD the orretion is more prolemti due to the lrge devition from liner dependeny nd shows lrger unertintiesF he horizontl lines in the plots indite the verge delt vlues lulted over ll wter onentrtions of the mesurementsD exluding onentrtions elow SH ppmv euse of the lrger unertintiesF he verged mesured delt vlues for the three mesurements long with the rel delts re shown in tle SFRF efter the orretion of the onentrtion dependenyD lirtion of mesured versus true delt vlues n e doneD ssuming liner reltion etween true nd mesured delts @fF equtions SFI nd SFPAF sn (gure SFWD plot of rel versus mesured delt vlues is shown for δ 2 rD δ 18 y nd δ 17 y djustment funtion for the unknown smple @here qPPA determined from liner omintion of the djustment funtions from the lirtions for A δ 2 rD A δ 18 y nd A δ 17 yF he light red re indites the unertinty of the funtion sed on the stndrd devition of the (t prmetersF he djustment funtion grees well with the onentrtion dependeny of the smple SFRX gorreting funtion for the onentrtion dependene for the smple mesurement @qPPA resulting from liner omintion of the funtions from the two lirtion mesureE ments verged delt vlues from the two lirtion nd the smple mesurement orreted for the onentrtion dependenyF A δ 2 r A δ 18 y nd A δ 17 yF he horizontl lines indite the verge delt vlues lulted for ll mesurement points with r 2 16 y b SH ppmvF vower wter onentrtions re exluded euse of muh higher unertinties due to the lrge ontriution of the nonElinerity in the onentrtion dependene funtion TV 5. Data Corrections and Calibration long with the liner lirtion funtionF he delt vlues re lso plot for qPPD the smple mesurementD to show the qulity of the onentrtion orretion nd lirtion proedureF ithin the error on the lirted deltsD they gree well with the true vluesF por the lirtion of our mesurementsD this results inX of the mesured delt vlue orreted for the wter onentrtion dependene ginst the true delt vlue for A δ 2 rD A δ 18 y nd A δ 17 y for the two lirtion mesurements with qRV nd qSHD verged over ll onentrtion steps ove SH ppmvF he error rs represent the IEsigm stndrd devition of the mesured vluesF he qPP vlue grees for ll three isotopes with the vlue given y the qRVEqSH lirtion linesF 9 + 0.9889 × δ 17 y (m) @SFVA with supersripts (c) nd (m) for lirted nd mesured vluesD respetivelyF he lirted delt vluesD orreted for the onentrtion dependeneD re shown in (gure SFIHD with horizontl 5.1. Calibration strategy TW lines inditing the true delt vlues of the respetive isotope stndrdsF ithin the errorsD the lirted delt vlues gree well with the true vluesF o etter ppreite the ury of the lirtionD the w devition from the true vlue s delt vlues of the mesurementsD orreted for the onentrtion deE pendeneD ginst the mesured wter onentrtionF he horizontl lines indite the true isotopi omposition of the di'erent wter stndrdsF funtion of the wter onentrtion is shown in (gure SFIIF por wter onentrtions lrger thn SH ppmvD the stndrd devition is smller thn IH D R nd S D for δ 2 rD δ 18 y nd δ 17 yD respetivelyF por onentrtions elow SH ppmvD the error inreses euse of the lrge nonElinerity in the onentrtion dependeneF por higher onentrtionsD the onentrtion dependene is less pronouned @fF (gure SFRA nd the error stys elow the errors lulted hereF devition from the true vlue s funtion of the wter onentrtion for the @A δ 2 rD @A δ 18 yD nd @A δ 17 y isotope rtiosF 5.1.1 Concentration dependence in other spectral ranges sn the spetrl rnge t UPHH m -1 D with sorption lines of r 2 16 yD rh 16 y nd r 2 18 yD the onentrtion dependene of the delt vlues is lso est desried with eqution @SFSAF en ensemle of di'erent lirtion mesurements t UPHH m -1 verged for eh onentrtion stepD is shown in (gure SFIP in logElinEplotF he nonElinerity is omprle to tht oserved in the UIVR m -1 regionF e strongly enrihed isotope stndrd @fiPA ws usedF he hnge of the spetrl region from UIVR m -1 to UPHH m -1 D whih hs etter seprted sorption linesD does not redue the onentrtion dependeny of the mesurementsF his might e n indition tht the mjor soure of the onentrtion dependene re strong sorptions outside the reorded spetrl windowD whih dominte the seline shpe nd n e found in oth of the spetrl regionsF sn (gure SFIQD plot of 2 sample G 2 VSMOW versus the wter onentrtion is shown for (a) (b) pigure SFIPX et of A δ 2 r nd A δ 18 y verged over di'erent wter onentrtion steps from mesurements t UPHH m -1 F he di'erent olors indite di'erent lirtion mesurementsF es t UIVR m -1 D the onentrtion dependene is est desried with eqution @SFSAF mesurements t UPVH m -1 F he wter onentrtion dependeny is less pronouned in this spetrl region nd n e pproximted with liner funtionF et ny given onentrtionD the spred in the mesurements is lrger thn the orretion tht would e ppliedF pigure SFIQ shows 18 sample G 18 VSMOW versus r 2 16 y for mesurements t UPVT m -1 F es explined oveD this spetrl rnge is well suited to low wter onentrtion mesurements @setion QFTA nd in ft no mesurements ove SH ppmv were possile due to sturtion of the sorption signl on the strong trnsitions in this regionFF e possile wter onentrtion dependene is smller thn the mesurement error t ny given wter onentrtion nd n thus e sample G 2 VSMOW D mesured t UPVH m -1 nd A 18 sample G 18 VSMOW D mesured t UPVT m -1 for di'erent wter onentrtion stepsF he di'erent olors indite di'erent lirtion mesurementsF et UPVH m -1 D the onenE trtion dependene of 2 sample G 2 VSMOW n e pproximted with liner reltionF por mesurements t UPVT m -1 D possile onentrtion dependene of 18 sample G 18 VSMOW is smller thn the unertinty t one onentrtion nd no orretion is ppliedF Chapter 6 Calibration instruments he mesurement of isotope rtios is never n solute mesurement ut is lwys done in omprison with mesurements of known smplesD lled isotope stndrdsF hese dditionl lirtion mesurements re neessry to orret for instrumentl rtifts like nonElinerity or dependene of the isotope rtios on the onentrtion t whih they re mesured IIRF sn dditionD smll hnges of temperture nd pressure inside the sorption ell n in)uene the mesurement nd led to hnge in the mesured isotopi ompositionF hepending on instrument stility nd the dependeny of the isotope rtios on the onentrE tionD protool with frequent lirtion mesurements of di'erent isotope stndrds mesured t one or di'erent onentrtions hs to e estlishedF por these mesurementsD well determined isotope stndrds hve to e used to enle n interE omprison of the mesurements mde with di'erent instruments nd to lirte the vlues to the sle determined y wy nd ve @see setion IFPFIAF xormllyD the mesurements lirted with respet to lortory stndrdsD whih in turn hve een lirted y sw with respet to the interntionl stndrd mterils wy nd veF qenerllyD these stndrds re distriuted nd stored s liquid wterD wheres the optil speE trometers nlyze vpor phse wterF hereforeD proedure is required to trnsform liquid wter stndrds into wter vpor without hnging the isotopi ompositionD or lterntively with hnge of the isotopi omposition tht n e determined independently of the speE trometerF sf the liquid wter is evported only prtillyD frtiontion of the isotopes ours nd the isotopi omposition in the vpor phse wter no longer orresponds to the omposition of the liquid wterF sn dditionD one would like to vry the mount of wter in the gs phse to e le to mke isotope mesurements t di'erent onentrtions nd study the e'et of these hnges on the isotope rtiosF xot lest euse of the inresed importne of optil spetrometersD numer of di'erent lirtion instruments hs een developedF everl groups TSD IISD IIT propose to use hew oint qenertor @hqA to injet smll mounts of wter into dry ir strem nd lulte the isotope rtios sed on yleigh distilltion urvesF roweverD in these lirtionsD the temperE ture hs to e mesured very preisely to determine the ourring frtiontion nd with smller wter reservoirsD the liquid wter eomes inresingly enrihed in the hevier isotopologuesF sn dditionD these lirtions often require long time to stilize nd equilirte nd re typilly done for IP to PRhF en lterntive wy for the mesurement of di'erent liquid smples is the UR 6. Calibration instruments injetion of smll mount of liquid wter into heted hmer nd to mesure the pulse of the evportion IIUF sn omintion with n utosmplerD this proedure is well dpted to utomtilly mesure lrger numers of liquid wter smplesF roweverD for ontinuous meE surements of vpor phse wter nd smll mounts of wterD this method is not well suitedF enother possiility is to simply (ll pressurized tnk with mixture of wter stndrd nd dry irD s ws demonstrted in our group TF his works well s long s the dew point temperE ture of the wter in the tnk is lower thn mient ir tempertureF e drwk is tht the isotopi omposition ould e 'eted y surfe e'ets inside the tnkF snnone in his hh work IIV estlished tht with seleted tnks tht were previously onditioned with isotopiE lly the sme wterD the isotopi frtiontion ws smller thn the mesurement preisionF he remining drwks then re tht the isotope rnge tht n e overed is limitedD tht the wter onentrtion is not esily vriedD tht the tnk preprtion is time onsumingD nd (nlly tht the tnk is ig nd hevyF elterntivelyD snnone et lF IIW nd lter turm nd unohl IPH demonstrted the suessful implementtion of wirodrop lirtion systemF ith piezoeletri mirdroplet genertorD suEmiroliter volumes of wter re injeted into dry ir stremF feuse of the smll volumeD the wter is immeditely evported nd no frtiontion oursF ith n unheted evporE tion hmerD this method n e used to generte wter onentrtions etween IP nd QSHH ppmvF he wirodrop lirtion systemD whih ws lso used for mesurements of this thesisD is desried in more detil in setion TFIF e lirtion instrumentD developed y vee nd oEworkers TSD TTD llows for more esily djusted wter onentrtionF his devieD lled dripper y the uthorsD uses syringe pump to ontinuously injet wter with syringe pump into heted evportion hmer nd trnsE ported to the spetrometer y dry ir stremF fy hnging the wter injetion rtes etween I nd IP µlGminD the wter onentrtion n e vried etween VHH nd QHDHHH ppmvF imilr devies were uilt y qkinis et lFIPI nd remoyD gttni et lF IPPF sn the ltter deviesD strem of liquid wter of pproximtely HFS µlGmin is generted with syringe pumpF prom the min smple lineD smll frtion is splitEo' nd direted through fused sili pE illry towrds hot ovenD stilized t IUH°g with shEontrolled heterF he pillry hs n inner dimeter of IHH µmD whih imposes k pressure nd e0iently redues the wter injetion into the evportion hmerF hrough the hmerD dry ir )ow is guided nd trnsports the wter vpor to the spetrometerF heres the lirtion devie of qkinis et lF works relile etween IUDHHH nd PPDHHH ppmD the instrument of remoyD gttni et lF ws tested etween PHHH nd QHDHHH ppmvF efter n dption to lower wter onentrtionsD this

√

  of )ow nd pressure s well s the ontrol of )owD pressure nd eletroni vlves is done vi two dt quisition rds @xtionl snstrumentsD wesurement gomputingAF he syringe pumps re onneted to omputer through uiltEin f portF por the omined redEout nd ontrol of ll omponents of the lirtion setEupD we developed new vview progrmF his progrm llows to run fully utomtized lirtion yles with hnges in gs )ow nd wter injetion rtes s well s hnges etween the two injetion linesF (a)(b) pigure TFPX hemtis of xsg @A nd the )ow hmers in whih the wter is evported @A 6.2.1Modeling of the syringe injection sn (gure TFQD the tip of syringe needle with wter droplet during stle lirtion run is shownF he wter exiting t the tip of the syringe needle does not immeditely evporte upon injetion from the stndrd reservoir inside the syringe ut uilds droplet from whih 6.2. Syringe Nanoliter Injection Calibration System UW evportion oursF o good pproximtion the evportion rte will e proportionl to the exposed surfe re of the dropletF hereforeD initilly the evportion rte is smller thn the supply rte of wter from the reservoir through the needle @rmilton gompnyD guge PTD internl dimeter a HFRTR mmA nd the droplet will grow in sizeF tedyEstte will e rehed when the evportion rte equls to wter supply rteF sn the following prgrphs we will derive equtions desriing the dynmis of the droplet nd its isotopi ompositionF e ssume the droplet on the syringe needle from whih wter is evported to e spheril p @fF (gure fFIA with volume V drop F he evportion from droplet inevitly results in isotope frtiontion etween this volume nd gs phse wterF roweverD s the syringe injetion gives onstnt supply to the dropletD lwys yielding the sme isotope rtioD in stedy stte onditionsD this leds to n equilirium with n enrihed wter droplet suh tht the liquidE vpor frtiontion renders the isotopi omposition of the vpor phse equl to tht of the wter supplied from the syringeD s will e shown elowF es evportion ours t the surfe lyer of the droplet onlyD the surfe will e strongest pigure TFQX smge of the syringe needle tip with droplet during lirtion run enrihed in the hevier isotopes with grdient of the isotope rtio perpendiulr to the surfeD whih is determined y the di'usivity of the hevier isotopesF he inhomogeneity of the wter droplet in the di'erent isotopes n e estimted y the verge distne @hevyA wter moleule hs trveled in the droplet due to di'usionF he di'usion length L n e lulted with IQRX L = 2 √ Dt with D the di'usion oe0ient nd t timeF he di'usion oe0ients of rhy nd r 2 18 y in wter hve een mesured to e 2.34 • 10 -9 m 2 /s nd 2.66 • 10 -9 m 2 /sD respetively IQSD yielding the di'usion lengths for Is of 110 µm nd 117 µmF hey re thus of the sme order of mgnitude s the rdius of the droplet nd we n mke the ssumption tht the entire droplet nd not just surfe lyer is eoming enrihed in the hevier isotopesF feuse of injetion rtes s low s 100 nlGminD the di'usion veloity is omprleD ut opposite VH 6. Calibration instruments in signD to the veloity of the wter )ux injeted with the syringeF e thus hve to determine if the di'usion is lrge enough to hnge the isotopi omposition in the syringe itselfF he syringe needleD whih is generlly used for the lirtionsD is PT guge needle with SI mm length @rmiltonA nd RTR µm inner dimeterF he speed of the )ux inside the needle t IHH nlGmin is thus v f lux = 100 nlGmin A needle = 12 µmGs with A needle the internl ross setion of the needleF o lulte the penetrtion depth in the needle of the di'using hevier isotopologuesD we equte the di'usion length nd the distne rossed of the injetion )ow 2 Dt = t • v f lux whih leds for r 2 18 y to t = 4D v 2 = 74 s he penetrtion depth inside the needle is thus L needle = t • v f lux = 0.9 mm @TFIA his orresponds to n enrihed volume of IIRFSU nl inside the needleF ith totl length of SI mm of the needleD this is however less thn P7 of the needle lengthF e thus onlude tht the isotope rtio in the syringe volume itself is not hngedF snsted of n isotope rtio grdient inside the dropletD we ssume n enrihed surfe lyer volume nd ore volume with the isotope rtio of the wter stndrd @(gure TFRAF his mens tht the syringe lirtion system is uilt of three di'erent wter volumesX IA the syringe reservoir with onstnt isotope rtio R 0 of the given wter stndrd nd )ow rte Φ 0 (t)D whih is determined y the injetion speed of the syringe pumpF PA the ore volume of the dropletD whih hs time dependent volume V C (t) nd onstnt isotope rtio R C (t) = R 0 F QA he surfe lyer of the droplet with volume V S (t) nd isotope rtio R S (t)D whih is in)uened y the evportion from the surfe lyer nd ontinuous supply of the isotope stndrd from the ore volume V C F por the surfe volumeD we ssume onstnt thikness dD whih is determined y the di'usion of wter moleules in the surfe lyerF por smll dD we n pproximte V C to e the surfe re A S multiplied with the thikness of the lyerX V S (t) = A S (t) * d @TFPA VI elterntively to the volume of eqution @TFPAD the volume n e tken equl to the entire droplet volumeD whih would e the limiting se for lrge di'usion oe0ients with su0iently high )ow speed in the needle to void k di'usion into the syringe reservoirF (a) pigure TFRX wodelling pproh for the wter injetion with xsgF ter from the syringe reservoir is injeted into ore volume V c with identil isotopi ompositionF prom the ore volumeD the wter is trnsported to n enrihed surfe volume V s with isotopi omposition R s (t)F e detiled disussion of the model n e found in hpter fD here we only present the resultsF fsed on our modelling pprohD the isotope rtio of the enrihed surfe lyer n e lulted y R S (t) = ψ(t) 1 + ψ(t) @TFQA nd the isotope rtio of the vpor phse with R e (t) = R S (t) • α V we will now ompre the results of the theoretil model desried oveD with rel experimentl dtF yther thn the modelD the experimentl dt is smoothed euse the response time of the ypEgie spetrometerF o inlude this response into our modelD we (lter the model output y douleEexponentil time responseF he two time onstnts of the exponentil were determined in trnsition experiments with the rel instrument nd were set to τ 1 = 30 s nd τ 2 = 300 sF sn dditionD the two exponentil funtions were weighed di'erentlyD with ten times lrger mplitude of the fst time responseF 6.2.3 Calibration with two syringe pumps he use of two di'erent injetion lines o'ers the possiility to quikly hnge etween two di'erent wter stndrds or etween di'erent onentrtions of the sme wter stndrd without the penlty of n dditionl time dely euse of the time required to reh new stedy stte of the injetion moduleF sn (gure TFSD mesurement with regulr hnges etween the two injetion lines is shownF yne syringe pump ws used to injet slightly depleted stndrd

  run for one wter onentrtionD with ISH nlGmin wter injetion nd n ir )ow rte of QHH smF @A ter onentrtion nd isotope rtios during the entire lirtion runF he wter onentrtion shows n osilltionD whih is used y vrition of the injetion rte due to the syringe pump @A pp of the wter onentrtionD yielding n mplitude of PFP ppmv nd frequeny of 2.357 × 10 -3 rz of the osilltionD leding to period of RPR s whih orresponds extly to the period of revolution of the led srew of the syringe pumpF he mplitude of the osilltion is thus smller thn I7 of the totl wter onentrtionF sn (gure TFUD lirtion run with onstnt ir )ow of IVH sm nd wter injetion rtes etween IH nd IQH nlGmin is shownF sn (gure TFUD the nonEverged wter onentrtion mesurement is shown together with the wter onentrtion lulted from wter injetion nd ir )ow rtesF he light gry urve shows the entire mesurement dt wheres the lk indites the dt used to verge over eh onentrtion stepF sn the rw dtD four sudden drops in the wter onentrtion re visileF hese disruptions re due to the formtion of ir ules t the onnetion from syringe to needle nd whih distur euse of their lrger ompressiilityF he formtion of ir ules n e voided following more reful syringe (lling proedureD in whih the syringe is (lled with smll disposle syringe from the k nd the plunger is inserted only fterwrdF sn (gure TFUD the verge wter onentrtion of eh injetion step hs een plot ginst the lulted wter onentrtionF he reltion etween lulted nd mesured wter onentrtion is perfetly linerF he interept of IH ppmv is due to residul wter in the rrier gsD wheres the slope of IFHPW proly origintes from unertinties in oth the ritrn prmeters for the intensities of the sorption lines @for the r 2 16 y line t 7183.6858 m -1 D the unertinty is S E IH7 TID IQUA nd the unertinties in the ir )ow mesurement @HFT7D IQVA nd the wter injetion rte @HFQS7D IQWAF es mentioned in the model of the syringe injetion @setion TFPFIAD the very low wter injeE tion rtes used with xsg result in injetion veloities tht re of the sme order of mgnitude s the di'usion veloities of the moleulesF fsed on the estimte given oveD the di'usion (a) (b) pigure TFUX vong term lirtion mesurement with di'erent wter injetion steps to hnge the wter onentrtionF A the rw rPy mesurement ompred to the lulted wter onenE trtion sed on wter nd ir )ow rtesF A he liner (t of the verged wter onentrtion t eh lirtion step versus the lulted wter onentrtion shows perfetly liner deE pendeneF however does not led to hnge of the isotopi omposition of the wter reservoir in the syringe itselfF sn the se of di'usion veloities tht re lrger thn the injetion veloity in the syringe needleD the wter in the syringe would eome inresingly enrihed throughout lirtion runF sf this would e the seD the wter vpor would lso show n inrese of the hevier isotopoE logues during the lirtionF por n experimentl investigtionD severl mesurements were mde with stle injetion of wter over the entire syringe volumeF sn order to lirte the mesurements nd to seprte instrumentl drift from grdul hnge of the isotopi rtios in the syringe volumeD we frequently swithed from xsg to n injetion of the sme stndrd with the piezo injetor @IIWAD in whih no frtiontion of the wter throughout mesurement oursF ghnges etween the two lirtion methods were done y hnge of the injetion lineD in oth lines the wter injetion nd stle ir )ow were mintined over the entire mesurementF e mesurement with regulr swithing etween xsg nd piezo injetor is shown in (gure TFVD with A the wter onentrtion during the mesurement nd A δ 2 rF hroughout the lirE tionD instrumentl drift leds to derese of the isotope rtio for oth lirtions ut the isotope rtio for the syringe injetion shows no systemti di'erene or hnge over time omE pred to the piezo injetionsF his mens tht no hnge of the reltive isotopi undnes or hnge smller thn the instrumentl drift ours during the syringe lirtionsF sn onlusionD the new yringe xnoliter snjetion glirtion ystem o'ers roust nd preise lterntive to other lirtion methods suh s ulers or piezo injetor nd n e used for long mesurements for instrumentl hrteriztion s well s for norml interE mesurement lirtion runs t one or severl onentrtions with up to two di'erent wter VS (a) (b) pigure TFVX e lirtion run with regulr hnges etween injetion of the sme wter stndrd y piezo injetor nd xsgF stndrdsF he uildup of wter droplet nd the time until equilirium with stle isotope rtios n tke severl minutesF es soon s equilirium is rehedD the isotope rtio in the vpor phse is identil to the isotope rtio of the wter stndrd nd no frtiontion inside the syringe reservoir ours due to di'usionF fy hnging etween two di'erent syringe injetion linesD fster hnges etween di'erent onentrtions or stndrds is possileF sn the urrent setEupD opertor invention is still required to re(ll the syringesF roweverD we pln to remedy this drwk y equipping the system with system with QEwy liquid )ow vlve immeditely following the syringeD either direting the syringe output towrds the needleD or enling the syringe to e re(lled from losed stndrd wter reservoirF he re(lling is possile with the syringe pump model used in xsgD whih o'ers withdrw modeF Chapter 7

  4 × p out AF ith n inner dimeter of the nozzle of IHH µm nd tmospheri pressure t the inletD the )ow ws regulted to IIH sm during the mpignF e photogrph of the entrti ypEgie setEup is shown in (gure UFP with the em pth indited in yellow nd some of the optil elements highlighted in redF he ringEdown timeD whih ws in lter version of the instrument inresed to up to ISH µs for this wvelength regionD ws limited to VH µs euse of the lower re)etivity of the mirrors tht were usedF 7.2. Local set-up VW pigure UFPX he ypEgie spetrometer design used during the entrti missionF sn yellowD the em pth is inditedF 7.2 Local set-up feuse of the requirement of su0ient power supply nd n insulted mesurement ontinerD we were ound to instll our mesurement setEup in the lose viinity to the min omplex of the sttionF o e the lest in)uened y emissions of the sttion itselfD the spetrometer ws instlled in smll insulted ontiner pproximtely PHH m from the min uilding nd situted t the order of the sttion rrngement @see (gure UFQAF he mesurement inlet tuing ws direted in westEnorthEwest diretionF heres in the winter hlfEyerD winds re most of the time oming from xorthEist nd istEouthEistD the wind diretion in the summer months is more )ututingD ut with medin round QH°IRPF sn (gure UFRD polr digrm of wind t roll ttion during the mesuring period in tnury nd perury PHII is shownD the dt ws provided y the xorwegin snstitute for eir eserh @xsvAF epproximtely RH7 of the timeD the wind ws oming from orridor of PPFS°to IQS°D orresponding to the diretion of min uildings of the sttionF enother RH7 of the timeD wind ws oming from outh nd est @ISUFS°to QQUFS°AD nd PH7 of the time from xorthD whih is the diretion of minor sttion uildingsF o void ontmintion of the olleted ir smple y the opertion of the reserh sttionD it would hve een etter to mesure t lrger distne of the sttion uildingsF nfortuntelyD euse of the neessity of power soure nd lol infrstrutureD neither this nor mesurement lotion to the north est of the sttion ws possileF pigure UFQX hotogrphy of the rrngement of roll sttionD with n rrow inditing the ontiner used for our setEup throughout the mesurement mpignF yn the ottom of the (gureD ompss hs een dded to indite rdinl diretionsF he spetrometer ws instlled on tle inside the ontinerD whih hd size of pproxiE mtely P x PFS x P m nd volume of IH m 3 F he inlet tuing ws ilotek treted stinless steel tuing onneted to the outside vi venting slot in the wll of the ontinerF o void freezing or logging of the tueD it ws onstntly heted to pproxF SH°g with selfEregulting heting nd @rorst qmrA nd thermlly insultedF o void snow entering diretly into the inlet tuingD smll plsti over ws mounted round the inlet @(gure UFSAF feuse of the smll size of the mesurement ontinerD solr heting during dy time in omE intion with the het generted y the eletronisD in prtiulr y the heting nd nd the heting of the lirtion devie @see setion UFQFIAD led to n inresed temperture of up to QH°g in the roomF ogether with the het generted y the internl power supply of the ypE gie spetrometerD this led to prolems in the temperture stiliztion of the spetrometer itselfD whih ould not e su0iently ooledF his prolem ws lrgely solved y instlling n ir fn in front of one of the venting slits of the ontinerD whih deresed the temperture in the ontiner to elow PH°gF sn dditionD the temperture inside the spetrometer ws inresed from QS°g to RH°g to inrese the di'erene to room tempertureF 7.3 Calibration procedure 7.3.1 Syringe pump calibration feuse of preEmpign prolems with proper funtioning of the piezo injetor @setion TFID IIWAD n lterntive lirtion method ws used during the mpign in entrtiF por the 7.3. Calibration procedure WI pigure UFRX olr digrm of wind t roll ttion during the mesuring period in tnury nd perury PHIIF he wind ws often oming from xorthEist with interim winds from outhEestF mpignD syringe pump sed lirtion systemD developed y ylivier gttni from the

  his lirtion system ws designed to work with ommerilly ville spetrometersD whih typilly mesure severl IHDHHH ppmv nd more thn SH7 of the injeted wter is sent pigure UFSX he inlet for tmospheri ir during the mesurement mpignF he oted tuing ws heted to SH°g nd thermlly insultedF e plsti over round the inlet voided perturE tions euse of snow fll pigure UFTX he vgi lirtion systemD sed on syringe pump to the evportion hmerF es our ypEgie spetrometer mesures in rnge of PHH ppmv `r2 y `RHHH ppmvD the wter injetion rte hs to e redued muh furtherF ith n ir )ow rte of P slmD wter onentrtion of IHHH ppmv orresponds to n injetion rte of IFS µvGminD thus only II7 of the totl wter injetion rteD wheres the reminder hs to e send to the wste lineF huring prior test mesurements in the lD the vgi lirtion system worked quite reliE le nd showed only smll )ututions of the wter onentrtion during the lirtion runsF roweverD during (eld employmentD the lirtion turned out to e very sensitive to smll hnges in the onditions in the mesurement ontinerF he djustment of the wter )ow frtion to the wsteD whih is the most sensitive prt of this lirtion systemD proved to e nerly impossile in the (eldF iven smll hnge of the height of the end of the wste tuingD whih results in smll pressure hnge in the tuingD led to lrge disturne of the wter onentrtionF sn dditionD the ft tht the temperture in the mesurement ontiner ould not e stilized led to further instilitiesF 7.3. Calibration procedure WQ es mentioned oveD the lirtion system ws designed to provide muh higher wter onE entrtions thn mesured with our spetrometer nd the need to drstilly redue the wter injetion rtes resulted in muh lrger sensitivity of the system stility to the hnge of ny one prmeterF feuse of the lrge sensitivity of the lirtion system to the ext settingsD it hd to e preisely set efore eh lirtion run nd often eme unstle fter some minutes of reltively stle wter injetionF sn (gure UFUD two exemplry lirtion runs with the syringe injetion system during the entrE ti mission re shownF sn (gure UFUD lirtion with the qroningen stndrd qRV is shown nd in UFUD lirtion with the stndrd qPPF elthough the wter onentrtions were reltively stle @mplitude of osilltions on r 2 y `IHH ppmvAD strong vritions nd periodi osilltions of the delt vlues re pprentF hese osilltions re due to the formtion of smll wter droplets on the tip of the pillryD whih ourred proly euse of pressure )ututions inside the evportion hmerD indued y vrition of the ir )ow through the hmerF feuse of lrger frtiontion ftors nd stronger memory e'etD they re more pronouned in δ 2 r thn in δ 18 yF (a) Calibration with GS48 (b) Calibration with GS22 pigure UFUX ixemplry reltively stle lirtion with the syringe lirtion system used in roll 7.3.2 Bubbler feuse of the high sensitivity nd instility of the syringe lirtion system during the mpignD we eventully deided to knok together uler s simpler nd more roust lterntive lirtion systemF es explined in hpter TD the priniple of the uler is sed on the sturtion of n initilly dry gs )ow guided s ules through volume of liquid wterF hue to reltively lrge trnsit time @severl seondsAD the gs ules get sturted in wter nd n equilirium etween liquid wter nd gs phse wter n e ssumedF he temperture WR 7. Water vapor isotopologues in Antarctica of the wter olumn ws mesuredD suh tht the orresponding wter sturtion vpor pressure PQ nd equilirium frtion ftor QT ould e determinedF he (rst gives the wter mixing rtio when omined with the mesured pressure ove the wter olumnD wheres the seond quntity gives the vpor phse isotopi rtio when omined with the liquid phse isotopi rtioF por this resonD smples of the wter inside the uler were tken t the eginningD s well s t the end of the experiment nd nlyzed y swF es the uler used hereD hd to e ssemled in the (eldD it is reltively simple version ompred to other implementtions QUD SPD IPQ!IPUF e shemtis is shown in (gure UFVF he inlet pressure of the uler ws regulted with omo pigure UFVX hemtis of the fuler lirtion system used during the entrti mpign pressure regultor @sgs lo snstruments goF snFA to pproxF IFS rF he regultion of the dry ir )ow nd the )ow through the wterD ws done with two mnul proportionl vlves nd the )ow ws mesured with two eletroni )ow meters @roneywell QQHHAF he downstrem pressure ws mesured with n eletroni pressure meter @roneywellA nd redEout with n eletroni he rd @xtionl snstruments fTHHWAF he uler ws uilt from n empty hrierite rtridge (lled with lol wter melted from the ie lyer surrounding the reserh sttionF he temperture of the uler ws mesured with n eletrilly isolted xg thermistor @fetriw ensorsA inside the wter reservoirF he redEoutD y mesuring the voltge @supplied y the he rdA over IHkΩ resistne onneted in prllel to the thermistorD yielded preision of Q mu nd ury HFP uF he entire )ow through the uler system ws guided to the ypEgie instrumentF feuse of thisD hnge of the wter onentrtion mde n dption of oth the dry ir )ow rte nd the )ow rte through the uler neessry to gin mth the )ow of the spetrometerF es only one wter ws ville in su0ient quntities to (ll uler for the lirtionD it ws not possile to do twoEstndrd lirtion nd pply liner orretion of the delt vlues s reommended eFgF y the snterntionl etomi inergy egeny PTF snstedD only sling ftor ws lulted to orret the mesured delt vlues from the lirtions nd yield the 7.3. Calibration procedure WS rel vluesF his ftor ws lulted from the isotope rtiosX

  nd δ 18 O max -δ 18 O min = -52.81 + 53.53 = 0.72 F hroughout n individul lirtion runD the hnge of the wter temperture ws mximl muh smllerD nd lwys less thn P °gF 7.3.3 Calibration measurements at Troll Station feuse of the temperture sensor mounted in the gs strem inside the vity @fF setion QFSAD the gs )ow temperture is reordedF huring the mesurement mpignD the gs temperture inside the vity ws on verge equl to QWFH °gD with sixEσ vrition of IPFQ °g @see (gure UFWAF he vity temperture ws RHFP°g with sixEσ vrition of RFV °gF he quite high vrition of the vity temperture is prtly due to prolems with the redEout of the temperture sensorD whih led to prtil erroneous redEout of the temperture @the spikes oserved in (gure UFWAF he rel vity temperture is thus more stle thn the (gure of RFV °g suggestsD with tul vritions limited to less thn HFW °gF he lrge vritions of the gs )ow temperture re strongly orrelted with externl onditions pigure UFWX he vity nd gs temperture inside the instrument for the mesurement period in entrtiF he gs temperture is muh more sensitive to externl in)uenes thn the temperture of the lrge vityF like mient ir temperture nd wind speedF his is proly relted to insu0ient therml inE sultion of the inlet tuingD whih resulted in lrger vritions in the selfEregulted heting of the tuing nd susequently in stronger )ututions of the gs tempertureF feuse of the lrge 7.3. Calibration procedure WU gs temperture vritionsD ll mesurements hve een postEorreted for the @foltzmnnE Avrition of the sorption line strengths indued y the temperture hngesF sn (gure UFIHD n exmple of the e'et of the gs temperture orretion is shown for δ 17 yD for whih the temE perture dependene is strongest @fF tle QFIAF sn (gure UFIH the unorreted nd orreted mesurements re ompred for single lirtion run nd in (gure UFIHD ll lirtions over n IIEdy period re shown for δ 17 yF sn oth sesD the orretion lerly results in derese in the delt vlue vrition nd underlines the importne of this orretionF (a) (b) pigure UFIHX gorretion of the isotope mesurementsD exemplrily shown for δ 17 yF sn A the orretion is shown on n individul lirtion run nd in A the orretion for the entire mesurement period is shownD oth showing the strong e'et of the gs temperture on the isotope rtiosF sn (gure UFIID n exemplry lirtion mesurement is shownF ih lirtion ws done

δ

  18 y of ll lirtion runsD orreted for the onentrtion dependeneD is shownF o estimte the instrumentl drift throughout the mesurement mpignD the verge delt vlues for the onentrtion step losest to IHHH ppmv of ll lirtion runs re ompred in (gure UFIQF ith n verge time etween two lirtions of IPFRShD the verge di'erene etween two lirtion runs is UFP for δ 2 rD HFT for δ 18 y nd RFU for δ 17 yF o estimte the unertinty introdued in the mesurements euse of the onentrtion dependeneD we tke the verge isotope rtios for ll onentrtion steps nd determine for eh lirtion run the di'erene etween mximum nd minimum isotope rtio for the two isotopoE loguesF he verge di'erene of the isotope vlues in single lirtion run is UFR D S nd RFS for δ 2 rD δ 18 yD nd δ 17 y respetivelyD with n verge di'erene in wter onentrtion of PQHH ppmvF hen δ 18 y is orreted for the onentrtion dependene with liner dependeny WW delt vlues over ll lirtion steps of the fuler lirtions from HVEHP till IVEHPEPHIID A δ 2 rD A δ 18 y nd A δ 17 yF s desried oveD the verge di'erene in δ 18 y dereses to IFW F es the lirtion runs lwys lsted more thn one hourD these estimtes lso inlude drift over the lirtion run nd will in relity e slightly smllerF he lrge drifts in the delt vlues throughout the mesurement mpign proly originte in instilities in the ypEgie spetrometer during the mpignF es mentioned oveD the temperture regultion of the spetrometer proved to e di0ult euse of too muh het generted y the eletronis in the ontiner nd inside the instrument itselfF he instlltion of fn nd the inresed temperture in the spetrometer did improve the stility ut lso resulted in reltively lrge hnges in the room temperture of up to IS °gF es the ontinuous opertion of the fn would hve deresed the temperture too muhD it ould only e powered from time to timeF o lirte the mesurementsD the verge delt vlues were lulted for eh lirtion nd the delt vlues of eh mesurement were sled with the verge ftor from the two emring lirtionsF feuse of the reltively lrge unertinties in the delt vluesD the δ 17 yEexessD whih is luE (a) Linear t to correct for the concentration dependence of δ 18 O. The individual calibrations have been shifted as described in the text to be able to t the concentration dependence of the ensemble of all calibration (b) δ 18 O of the calibrations during the Antarctica mission, linearly corrected for the concentration dependence pigure UFIQX istimtion of the instrumentl drift resulting in hnges of the delt vlues etween di'erent lirtion runsF por eh lirtionD the verge delt vlues for the onentrtion step losest to IHHH ppmv is shownFs lted with δ 17 yEexess= ln(1 + δ 17 O) -0.528 ln(1 + δ 18 O)RR nd is usully given in per meg vritionD is not relileF feuse of its high unertintyD δ 17 yD whih is generlly only shown in omintion nd omE prison with δ 18 y in the form of δ 17 yEexessD is not further onsideredF 7.4 Measurement huring some episodes of the mesurementsD the ir )ow temperture inside the vity hnged quite drmtilly due to externl in)uenesF sn (gure UFIRD the gs temperture inside the vityD mesured inside the gs )ow @setion QFSAD is shown for two dy setionD together with the temperture of the vityD the temperture of the mient ir nd the wind speedF heres 7.4. Measurement IHI the vity temperture stys reltively stle throughout the mesurementD the gs temperture shows vritions of more thn R°gD whih re lerly orrelted with the wind speedF hese vriE tions re surprisingly strongD if one tkes into ount tht the ir is guided through more thn (ve meters of temperture stilized IGR inh stinless steel tuing nd dditionlly through (lter nd SH m of IGV inh stinless steel tuingD mounted inside the temperture stilized instrument itselfF hese strong vritions strongly underline the importne of independent gs temperture senE sors inside lser spetrometers omprle to oursD to e le to orret for line strength hnges due to vritions in the gs tempertureF he wter onentrtion nd isotope rtio mesurements shown in the following hve therefore een orreted for the hnges in the gs )ow tempertureD sed on the temperture oe0ients of the di'erent sorption linesF he wter onentrtion nd isotope rtios were qusiEontinuously mesured for period of II dys in perury PHIID with smll interruptions for lirtion runs nd smller dptions of the lser spetrometerF he wter onentrtionD δ 2 r nd δ 18 y mesurement for this period re shown in (gure UFIS together with n ir temperture mesurementD friendly provided y gF vunder from the xorwegin snstitute for ir reserh @xsvA F ysionlly during the mesurement periodD the temperture pprohed highs lose to H °gD whih together with strong solr rditionD resulted in wter onentrtions of more thn RHHH ppmvD whih is lose to the mximum our lser spetrometer ould mesureF sn dditionD the reltively mild tempertures resulted in sulimtion nd melting of the ie round the reserh sttion @see (gure UFIUAD nd led temporrily to strong omponent in the mesured wter vpor oming from lol wter insted of wter vpor trnsported to entrtiF feuse of the limittion imposed y lirtion proedure involving only one wter stnE drdD nd the ove mentioned drift nd wter onentrtion dependenyD the delt vlues lirted ginst the uler mesurements exhiit reltively lrge unertintyF hrift nd wter onentrtion dependeny led to n δ 2 r ury of pproxF IP D nd n ury of RFR for δ 18 yF feuse of thisD profound study nd interprettion of the oserved isotope rtio vritions during the mesurement period is not very usefulF roweverD euse some tmospheri events were ssoited with very lrge hnges in the isoE topi rtiosD whih ertinly re lrger thn the unertinty of the mesurementsD it is still possile to exmine if orreltion with tmospheri vritionsD espeilly in the soure regionD existF sn (gure UFIVD mesurement setion of two dys shows the wter onentrtionD the delt vlues nd the 2 rEexessF sn dditionD the ir temperture nd the wind speedD mesured y xsv in mesurement ontiner t IQHW m FsFlFD thus QR m ove the min uilding of the sttion nd t distne of pproximtely PHH m IRPD is shownF ntil pproximtely IIXHHh on ITEHPEPHII IHP 7. Water vapor isotopologues in Antarctica @IHFRT on the time sle given in the (gureAD the isotope rtios re reltively stleD with δ 2 r round EQPH nd δ 18 y round ERS F et IIXHHhD oth δ 2 r nd δ 18 y show rpid inreseD δ 2 r up to EPVH nd δ 18 y to EQP F et the sme time the hEexess deresesF e derese in the ir temperture took ple pproximtely one hour efore the hnge of the isotope rtios nd seems thus not e diretly orrelted with the hnge of the isotopi ompositionF roweverD strong inrese in wind speed seems to e strongly orrelted with the hnge of hEexessF et pproximtely IVXHH on the sme dyD the wind speed deresesD wheres δ 2 r nd hEexess show muh slower trnsition nd the trnsition for δ 18 y hppens round Q hours lter t pproximtely PIXHHF sn ddition to these strong hngesD temporry hnge of the wind diretion tht goes long with n inrese of wind speed nd ourred t aIIFISD diretly trnsltes into n inrese of ll isotope rtios nd thus indites reltively lrge in)uene of the wind diretion on the reltive isotope undnesF 7.4.1 Backtrajectories o determine if the oserved hnge of the isotopi omposition t IIXHH m on ITEHPEPHII nd the hnge k to the previous omposition t pproximtely IVXHHh for hEexess nd PIXHHh for δ 18 y on the sme dy re relted to hnge of the soure region of the tmospheri moistureD k trjetories were lulted with the online ville ryrid ingle rtile vE grngin sntegrted rjetory wodel @rvsA of the xtionl yeni nd etmospheri edministrtion @xyeeA IRTD IRU using the qlol ht essimiltion ystem @qheA meteoE rology rhiveF e set of k trjetories for the sme time frme s the experimentl dt in (gure UFIVD is shown in (gure UFIWF por etter overviewD the most importnt hrteristis of eh lulted k trjetory re given in tle UFIF he strong trnsitions in the isotope rtios oserved with our spetrometerD do not seem to e orrelted with hnges of the soure region of the humid irD nor with the ltitude of the irF wost of the timeD the ir strem is minly pssing over lnd nd oming from ltitudes round IHHH m ove ground levelF he rpid hnges in the isotopi omposition of the tmospheri moisture t roll sttion seems thus to e more orrelted with lol onditionsD suh s wind speed nd lol reEevportionF 7.5 Conclusion he mesurement mpign t roll sttion showed tht our lser spetrometer relily meE sures wter onentrtion nd the two isotope rtios δ 2 r nd δ 18 y with very good preisionF feuse of prolems with the onEsite lirtion of the isotope rtiosD the ury of the olE leted dt is unfortuntely not su0ient to drw detiled onlusions out tmospheri wter 7.5. Conclusion IHQ le UFIX fk trjetories for roll sttion for ITEHPEPHIID simulted with the rvs model of xyee IRTD IRU time hhXmm soure region ltitude of soure to re(ne tmospheri irultion modelsF he wter onentrtions enountered during the mesurements re well ove the miniml onentrtions tht our inE strument n mesured with good preisionD prtilly they were nerly too highF e omprison of the isotopi mesurements with k trjetory models reveled no orreltion etween the soure region of the ir mss nd our isotopi mesurementsF e strong reltion etween the lol wind speed nd the isotope rtios of mient ir indites tht lol pheE nomen proly govern the lol wter vpor ompositionF e possile explntion ould e for exmple the strong eddy winds on the mountin rnge tht resulted temporrily in wind speeds of more thn PP mGs during our mesurement mpignF purthermoreD the strong solr rdition nd high tempertures temporrily led to strong evportion of the lol snow nd strongly in)uened nd sometimes even governed the isotopi omposition of the tmospheri wter vporF sn order to nlyze tmospheri wter trnsporttion proesses nd to help to re(ne the theoE retil modeling of these proessesD we propose to ondut further mesurement mpigns on the entrti high plteuD for exmple t the prenh stlin reserh sttion home gonordiF his sttion is loted t @US°HT9D IPQ°PI9iA t n ltitude of QDPQQ m FsFlF IWD IRV he men nnul temperture of ERWFV°g @mesured in PHHWA orresponds t n verge pressure of TRRFR mr IRW to sturtion wter onentrtion of pproximtely TQ ppmvF sn the summer months heemer nd tnuryD the temperture rehes vlues of up to EPS°g nd thus wter onentrtions of severl hundreds of ppmvF yur ypEgie spetrometer would thus e lmost perfetly dpted to mesure wter vpor isotopologues in the hrsh environment of the entrti high plteuF feuse of the lotion on the high plteuD less eddy winds oming from inlnd regions re to expeted nd euse of the old temperturesD melting nd evportion of lol wter is less likely to in)uene the IHR 7. Water vapor isotopologues in Antarctica omposition of tmospheri moistureF he osionlly lrge drifts of the instrumentD used minly y temperture regultion proE lems nd mnifesting in reltively lrge di'erenes in the isotope rtios etween di'erent liE rtion runsD were e0iently redued with further improvements of the lser spetrometer fter the mesurement mpignF he opertion temperture ws further inresed to RS°g nd the internl power supply ws repled with n externl one to redue het prodution inside the thermlly insulted instrumentF feuse of the di0ulties enountered with the iezo injetor efore the mpign nd with the two other lirtion systems inEtheE(eldD new nd more roust system sed on highEpreision syringe pumps @setion TFPA ws developed nd o'ers more relile nd utomtized wy to perform isotope lirtions during future mesurement mpignsF IHS (a) pigure UFIRX he gs )ow temperture inside the ypEgie spetrometer ws in)uened y rpid hnges in the mient onditionsF eprt from hnges in the mient ir tempertureD strong winds round the reserh sttion resulted in lrge hnge of the ir smple tempertureF yther then the wind speedD the wind diretion hd no diret in)uene on the tempertureF he dt were postEorreted for the temperture vritionsF (a) pigure UFISX usiEontinuous wter onentrtion mesurement t roll ttion during II dys in perury PHIIF snterruptions re due to lirtion runs with the uler nd minor modi(tions of the ypEgie spetrometerF sn the top pnelD the wter onentrtion is shownD in the seond pnel δ 2 r nd δ 18 yF he third pnel shows wind speed nd wind diretion nd the ottom pnel the mient ir tempertureF IHU (a) pigure UFITX oom into n pprent spike in (gure UFISF he trnsition is reltively slow nd lsts for more thn PS minutesD showing tht the dt is rel nd not n experimentl rtiftF (a) pigure UFIUX gontinuously wrm tempertures nd strong solr rdition temporrily led to strong melting of the ie lyer round roll sttionD whih resulted in higher wter onentrtions in the mient ir nd lrge ontriution of lol wter vpor to the isotope rtios mesured y our spetrometer (a) pigure UFIVX etion of two dys @ITEHP to IVEHPA from the mesurement t roll ttion in perury PHII IHW (a) pigure UFIWX fk trjetories for roll sttion for ITEHPEPHIID lulted with the rvs model of xyee Chapter 8 Water isotope fractionation in simulated ice clouds rious mesurements rried out in the oldest regions of the tmosphere reveled the oE urrene of superEsturtion @prtil pressure of wter ove the sturtion pressureA in the presene of ie rystls in the upper troposphere ISHF uperEsturtion is wellEknown phenomenon in the sene of nuletion entersF roweverD it n lso our in the presene of foreign nulei tht initite heterogeneous freezingD or even in the presene of ie rystlsF wo hypotheses hve een forwrded to explin the ltter seF he (rst hypothesis is known s di'usionElimited superEsturtion ISID while the seond hypothesis is tht of equiliriumElimited rystlliztion ISPF es these two mehnisms would leve very distint signture on the isotopi omposition of the ie rystls nd the tmoE spheri wter vporD mesurements of the isotopi rtios n e exploited to determine their reltive importneF e shemti representtion of the two proposed mehnisms is given in (gure VFIF sn the di'usionElimited seD rystlliztionD e'etively reduing supersturtion to sturtionD is limited y the di'usion time of the wter moleules to the nulei with hevier wter isotopologues di'using more slowlyF his indues negtive grdient in the isotope unE dnes in the diretion of the ie rystlsF roweverD s the proility of dsorption is higher for hevier isotopologuesD the rystls re still enrihed in the hevier isotopesF et the sme timeD the reltive humidity dereses in lose proximity to the ie nuleiD s neighoring wter moleules freeze out fster thn new moleules n e replenished y di'usionF he seond possile mehnismD equiliriumElimited rystlliztionD ssumes tht the sorption pity of the ie rystls is the limiting ftor for the derese of the degree of superEsturtionF sn this seD the di'erent di'usion rtes of the isotopologues do not 'et the isotopi unE dnes in the ie rystlF gonsequentlyD the hevier isotopologues would e more undnt in the rystls thn in the se of di'usionElimited rystlliztion nd neither isotope rtio nor reltive humidityD would hnge in the proximity of the ie nuleiF fy mesuring the di'erent wter isotopologues seprtely in the gs phseD in ie rystlsD nd in the totl wter ontent in the ie loud hmerD we imed to investigteD whih of the ove mentioned mehnisms is primrily responsile for the superEsturtion e'ets oserved in the upper troposphere nd to experimentlly determine frtiontion ftors t very low temperturesF feuse of the di0ult essiility nd very low wter onentrtions @`IH ppmvAD meE surements to investigte these mehnisms in situ re until now to the est of our knowledge not fesileF he eshe loud simultion hmer t the urlsruhe snstitute of ehnologyD (a)

  single pss inEsitu hv @EeiA dditionlly mesured the wter onentrtion in the gs phseF e shemti representtion of the experimentl setEup is shown in (gure VFPD list of the di'erent instruments deployed during the ssoloud mpign nd their most importnt hrteristis re given in tle VFIF 8.1 General set-up he eshe loud hmer is mde of luminumD hs dimeter of R m nd height of UFS m with volume of VRFS m 3 nd n inner surfe of IHQ m 2 F e vuum pump is onneted to the top of the loud hmer nd is used to rpidly derese the pressure in the hmerD whih leds to n diti expnsion nd thus ooling of the ontined irF et the ottom of the hmerD fn is instlled to homogenize the ir inside the hmerF glose to the ground levelD the gs is onneted vi n extrtive tuingD ehind whih one of the ypEgie spetromE eters ws instlledF he seond ypEgie spetrometer ws onneted to ilotek otet IGR inh stinless steel tuing heted to QS °gD tht ws instlled pproximtely IQS m ove the se of the hmerF et distne of IQ m from the hmer wllsD ir ws extrted through the tuing with )ow rte of IQH smF st would hve een estD to onnet this seond ypE gie spetrometer t the sme lotion t whih the other extrtive instruments mesuring solute wterD were onneted nd t the sme level of the hmer s the in situ instrumentsF nfortuntelyD euse of limittions of the lol vililityD this ws not possileF snitillyD the spetrometer ws onneted lose to the top of the eshe hmerD however this did not work IIR 8. Water isotope fractionation in simulated ice clouds le VFIX e list of the di'erent instruments deployed during the ssoloud ssoloud I E QA r 2 16 yD rh 16 yD r 2 18 yD r 2 17 y mostly ie phse IFQVW µm @ssoloud RA r 2 16 yD rh 16 yD r 2 disturnes of the mesurements due to strong virtions of the metl frme on whih the instrument hd to e instlledF feuse of thisD lotion lose to the ottom of the hmerD whih provided more mehnil stilityD ws hosenF et height of pproxF R mD two white ells re instlled into whih the two hv spetrometers of the og nd fGus groups were oupledF he fGus instrumentD ssotope esheE gsEinEloudEhv @syEeiAD hnge etween two di'erent lsers ws mde possile to integrte the lredy existent fility hv hygrometer ei ISSD whih previously mesured gs phse wter on the sme em pth of the hite ellF en dditionl single pss hv spetrometer @EeiA ws onneted to the hmer t the sme level s the other hv spetrometers to independently mesure the wter onentrtion in gs phseF sn ddition to the ypEgie spetrometerD totl wter onentrtion in the loud hmer ws mesured y n extrtive vh spetrometerD AIDA PCI extractive TDL (APeT) nd hilledEmirror frost point hygrometer @wf QUQvA ISS onneted to the sme heted extrE tive line either on the third level of the loud hmer @pproxF T m heightA or on the seond level @pproxF RFS m heightAF he ssoloud projet omprised four mesurement mpigns tht (a) pigure VFPX ixperimentl setEup t the eshe loud hmer during the ssoloud mesurement mpignsD shemtis y rF tho' @usAF he ypEgie instrument ehind the gs ws typilly ssF were onduted in epril PHIPD tune PHIPD ytoer PHIP nd wrh PHIQF he two ypEgie IIT 8. Water isotope fractionation in simulated ice clouds spetrometers were in very similr on(gurtion for the (rst three mpigns nd mesuring t IFQWP µmD the wvelength region tht ws lso used during the mission to entrti @fF UF por the lst mpignD the us ypEgie spetrometer ws dpted to e le to mesure the r 18 2 yGr 16 2 y rtio in very dry ir s enountered in the strtosphereF hese dptions re desried in more detil in setion VFIFIF es the (rst two mpigns served minly s tril mpigns to test the di'erent optil instruE ments nd to revel where modi(tions nd dptions were neessryD the dt presented in the following is from the lst two mesurement mpignsD ssoloudQ nd ssoloudRF 8.1.1 Isocloud OF-CEAS heres the on(gurtion of our ypEgie spetrometer ws very similr to the one lso used for the entrti missionD severl modi(tions were mde etween the mpigns to dpt the instrument to the very demnding onditions tht were enountered during the mesurementsF es derese of the inlet pressureD s experiened y the spetrometer during the loud simulE tion experiments would result in hnging )ow with n ultrsoni nozzleD this )ow restrition ws ompletely removed from the instrumentF sn dditionD the vrileEspeed pumpD whih ws used to regulte the vity pressureD proved to e too wek to provide su0ient )ow t the lower pressuresF feuse of thisD estek oted fronkhorst pressure regultor ws instlled upstrem of the vity nd the vrileEspeed pump ws repled with n ordinry nd lrger memrne pump @uxp xVIQFS exiAF ith this modi(tionD the )ow through the instrument ould e inresed to ISH sm nd e kept onstntD even s the inlet pressure desended to elow IHH mrF por the lst mesurement mpign @ssoloudRAD we repled the lser in ewsEsso with lser operting etween UPUV nd UPWH m -1 F es mentioned in setion QFTD the sorption line of r 2 16 y is more thn ftor SHD nd the r 2 18 y line nerly ftor R stronger t UPVT m -1 ompred to the lines in the spetrl regions t UIVR nd UPHH m -1 F feuse of thisD the onentrtion rnge of the modi(ed instrument in whih suEpermil preision for δ 18 y n e hieved is signi(ntly redued to I ppmv `r2 y `TH ppmvF sn ddition to the mesurement of δ 18 yD spetrl region round UPVH m -1 llows the mesurement of δ 2 rF ineD t nturl undneD in this region the rh 16 y line is out RH times weker thn the mjor isotopologue lineD it is espeilly pproprite for mesurements of smples strongly enrihed in rh 16 yD s were generted during the ssoloud mpignsF wo experimentl spetr for the wvelength region t UPVT m -1 nd UPVH m -1 re shown long with (t to the dt in (gure VFQF he spetrum of (gure VFQ ws reorded t wter onentrtion of PQ ppmv nd the spetrum of (gure VFQ t WH ppmvF IIU VFQX ixperimentl spetr mesured with ewsEsso in the new wvelength rnge t A UPVT m -1 nd A UPVH m -1 F IIV 8. Water isotope fractionation in simulated ice clouds sn (gure VFRD the ellnEerle plot is shown for mesurements of δ 18 y t three di'erent onentrtionsF et IT ppmvD t the optimum integrtion time of QURH sD preision of HFIU is otinedF ith I s vergingD the preision is R t IT ppmv nd IS t S ppmvF pigure VFRX elln devition plot for ewsEsso in the r 18 2 y wvelength regionF et r 2 y a IT ppmvD nd n optimum integrtion time of QURH sD the preision is HFIU 8.2 Pumped Counterow Virtual Impactor (PCVI)

  wter onentrtionsF sn (gure VFWD the e'et of the R 2H lirtion is exemplry shown for one experimentF sn (gure VFW AD the unlirted isotope rtio is shown for grsEs nd in A the lirted dtF elthough one lirtion ws done for the entire mesurement mpignD the lirted dt gree within less thn IHH permilD whih is muh smller thn the isotopi hnges oserved in IPQ

IQH 8 .

 8 Water isotope fractionation in simulated ice clouds extrtion portsD the overll shpe of the wter onentrtion mesurement y ee is identil etween the two di'erent smpling heightsF his indites tht the di'erent shpe of the wter onentrtion mesurements of eeGwf nd ewsEsso is not due to di'erent smpling heightF pigure VFIRX gomprison of two susequent expnsion experimentsD in expF PH ee nd wf were smpling t R m height nd in expF PI t T mF feuse of di'erent mesurement onditionsD the wter onentrtions re not equl ut the shpe is identil for oth mesurement heights pinllyD the ridges inside the loud hmer tht improve its mehnil strengthD ould hmper good mixing of the ir loser to the wllsF he ridges extend pproximtely IH m into the hmerD whih is nerly the sme distne t whih ewsEsso is mesuringF roweverD this hypothesis ws exluded in n extensive hmer nd instrumentl interomprison study @equsEIA done in the eshe simultion hmer y phey et lF ITHF por experimentl onditions similr to the onditions enountered during the ssoloud mpignsD they found tht mixing rtio grdients re virtully nonEexistentF gph simultions nd simultneous mesurements t vrious eshe positions during the inE teromprison mpigns equs I nd P support our rguments ginst ll of the oveE mentioned hypotheses ITIF efter exluding lmost ll possile hmer relted resons for the oserved disrepniesD the use my rther e relted to the smpling system with rther smll )ow of ISH smF he di'erene in the totl wter mesurement of ie nd ee is well orrelted with the pressure hnge nd relxes t onstnt pressureF hereforeD prolems with the )ow ontroller system or dynmi lek seem possile uses for the oservtionF hespite numerous lek tests nd other investigtionsD neither of these lst two hypotheses ould e on(rmedF roweverD until now no )ow simultions in the hmer were done for isotope hnges nd prolem due to inomplete mixing of the hmer ir remins possiility s wellF he true use of the disrepny etween the instruments on the lower nd higher ir extrtion lines ould thus not yet e reveled nd remins speultionF 8

  loud expnsion mesurements @A strting t ESH °g nd with IHH prtilesGm -3 nd @A strting t ETH °g nd with SHH prtilesGm -3 F op pnelX r 2 y in gs phseD in the ie ehind the gs nd in totl wterF eond pnelX wesurement of two ygs @els nd elsPA of the prtile density in the loud hmerF hird pnelX he mximl prtile size in A is nerly 100 µm ompred to round 50 µm in AF fottom pnelX ressure nd ir temperture during the experiment IQQ pigure VFITX ixpnsion t ETH°gF op pnelX wesurement of gs phseD totl wter nd ie ehind the gsF genter pnelX rhyGr16 2 y in gs phseD totl wter nd ieF sn the ie phse wterD smll dip in the isotope rtio n e oserved shortly fter the eginning of the ie loud mesurementD whih is proly relted to the wter dynmis in the loud hmerF fottom pnelX ressure nd ir temperture during the experiment ground mesurement efore @left pnelA nd fter the expnsion @right pnelAF sn the enter pnelsD the orresponding δ 18 y mesurements of kground nd expnsion re given nd in the ottom pnelD pressure nd temperture during the expnsionF por (rst estimte of the frtiontion ftor in the experimentD we ssume onstnt frE tiontion ftor nd only trnsition from the vpor phse to ieD thus yleigh frtiontion proess with one sinkF e n then lulte the frtiontion ftor with the following formul @fF IFPFP nd IRSAX R nd R 0 the urrent nd initil isotope rtio nd N nd N 0 the urrent nd initil wter onentrtionD respetivelyF he δ 18 y vlues re 3.5 ± 0.8 nd 3.1 ± 0.7 for the hmer ir efore nd fter the expnsionD respetively nd 10.6 ± 1.8 for the ie phse ehind the gsF he wter onentrtion efore the ie loud formtion ws 8.12 ± 0.05 ppmv nd the lowest wter onentrtion during the expnsion @mesured with eiA 5.65 ± 0.07 ppmvF por the frtiontion oe0ient αD we then get 18 α = 1.018 ± 0.014F his is only (rst estimteD s no dditionl sinks nd soures for wterD suh s the hmer IQR 8. Water isotope fractionation in simulated ice clouds wll were tken into ountF sn dditionD the mesurement ehind the gs risks to e ised s only ie rystls of ertin size n e mesuredF iven with the improved detetion limit in ewsEsso of pproxF R in δ 18 y t wter onentrtions round PH ppmvD the stndrd error mde in the lultion of the frtiontion ftor @0.014A reltively highF e etter estimtion of the frtiontion ftors n e otined y the omprison of inEsitu mesurements of the gs phse @syEei nd grsEsA with mesurements of the totl wter @eeD wf nd ewsEssoAF sn dditionD more omplete model of the wter )uxes in the loud hmer hs to e developedD s ws done y ur vm of the niversity of ghigo s prt of her hh thesisF e rief introdution of this model will e given in the next setionD for more detils we refer to the hh thesis of uF vm nd ITPF pigure VFIUX ixpnsion t very low wter onentrtionF op pnelX wter onentrtion meE surement during the experiment @middleA nd kground mesurements efore @leftA nd fter @rightA the expnsionF widdle pnelX orresponding δ 18 y mesurements of kground nd expnsionsF fottom pnelX pressure nd temperture during the expnsion 8.5 Modeling of uxes in the AIDA chamber es the ie loud formtion experiments re done in (nite volumeD we hve to tke into ount intertions of the gs inside the hmer with the hmer wll nd the removl of ir from the hmer during the experimentsF IQS pigure VFIVX hemtis of the wter nd isotope )uxes inluded in the model pigure VFIV gives shemtis of the wter )uxes tht re simulted in the modelF hree di'erent )uxes of r 2 y re ssumedX IA e redution of [r 2 y] total in the hmer euse of the derese in pressureX ∆ [r 2 y] pump = [r 2 y] ir is onstntly stirred y mixing fnD we ssume homogenous isotopi distriution throughout the hmerD nd X R pump = R(t) @VFSA PA en exhnge etween vpor nd ie phse due to rystlliztion nd sulimtion ∆ [r 2 y] ice = [r 2 y] total -[r 2 y] gas @VFTA es totl wter the mesurement of ee is used nd for wter vpor the dt from eiF por the rystlliztionD yleigh distilltion is ssumed with @fF setion IFPFPA temperture hnge during n experiment is typilly of the order of only R°g to S°g during n ie loud formtionD liner dependene of the frtiontion ftor α on the temperture n e ssumedX α = a 0 + a 1 T @VFVA he o'set a 0 is free prmeter in the (t nd the slope a 1 is derived from the temperture dependene of the frtiontion ftor s desried y werlivt nd xief @QRD eqution @IFIHAAF he result is however insensitive to whether the formultion of werlivt nd xief is used or the formultion y illehøj ITQF α n e seprted into kineti nd equilirium frtiontion @setion IFPFPDQWDRTAX with α = α eq • α k equilirium frtiontion ftor n susequently e determined sed on equtions VFV nd VFIHF he wter tht sulimtes from ie to vpor is ssumed to hve the sme isotope rtio it froze tF QA e )ux of r 2 y from wll ie into the hmer irX ∆ [r 2 y] wall = ∆ [r 2 y] total -∆ [r 2 y] pump @VFIIA es the frtion of ie oming from the wll is muh smller thn the totl mount of wll ieD the isotopi omposition of the wll ie n e ssumed to e onstnt throughout n experimentF sn dditionD the hnge of the wll temperture is very smll during the diti expnsionsF feuse of thisD we n ssume tht the isotope rtio of the ie oming from the wll is prtilly onstntX R v,wall = const. @VFIPA he prmeter R v,wall is (ttedF e list of ll input dt nd prmeters used in the model is shown in tle VFPF 8.5. Modeling of uxes in the AIDA chamber IQU le VFPX snput dt nd prmeters used in the isotope )ux model prmeter

  prmeter α 1 sed on QR or ITQ he ieD pumpingD nd wll )ux omponents re determined for one seond time intervls y interpolted dt setsF he model is dpted to the experimentl dt with vevenergE wrqurdt lest squres (tF sn (gure VFIWD the isotopi rtio mesured y grsEs is shown for typil expnsion experimentD long with the model (t @top pnelAF sn the middle pnelD the di'erent wter )uxes ssumed in the model @see oveA re givenD showing the removl of hmer ir s negtive )ux nd positive )ux oming from the wllsF he )ux etween vpor nd ie is positive in the eginningD inditing trnsition from vpor to ie phse when the ir temperture dereses nd wter vpor sturtion is rehedF hen the temperture inreses t the end of the experimentD the vporEie )ux is negtiveD representing the trnsition from ie phse to wter vporF sn the ottom pnelD wter onentrtions mesured y ee nd ei re shown long with hmer pressure nd ir tempertureD showing the typil ehvior during the expnsion experiments s desried oveF fsed on the modelD equilirium frtiontion ftors hve een derived from the (t for series of ssoloud experiments t di'erent temperturesF he frtiontion ftors re shown in (gure VFPH nd ompred with previous results y other groups @QRD IPUD ITR!ITVAF he temE perture dependene of frtiontion ftors derived from our experiments gree with previous investigtionsF he reent proposition of higher frtiontion ftors t tempertures elow PSH u IPU is not on(rmedF IQV 8. Water isotope fractionation in simulated ice clouds pigure VFIWX pigure from ITPD op pnelX he isotopi rtio mesured y grsEsD long with the model (tF widdle pnelX wodel )uxes etween ie nd vpor @greenAD from the wlls @lkA nd due to the removl of hmer ir y the pump @lueAF fottom pnelX otl nd vpor phse wter onentrtions mesured y ee @lueA nd ei @greenAF sn dshed red hmer ir temperture nd in dshed lk pressureF 8.6 Summary of Isocloud elthough it ws not yet possile to determineD whih of the two mehnismsD di'usionElimited frtiontion or equilirium frtiontionD is responsile for the supersturtion oserved in the upper tmosphereD the ssoloud projet yielded very promising resultsF st ws possile to estlish mesurement protool to e0iently mesure ie loud formtion t tempertures s low s EVH°g in vpor phseD totl wter nd ie phse simultneouslyF feuse of the isotope lirtion of the externl ypEgie spetrometersD we ould lirte the internl hv spetrometers nd redue the reltive error to `I7 on very lrge isotopi enrihmentF he ie phse ws suessfully mesured with the ypEgie instruments ehind the gs nd (rst omprison of the isotope rtios in ll three phses ould e doneF ewsEsso ould e suessfully dpted to mesure δ 18 y with four times higher preision thn efore nd t wter onentrtions s low s few ppmvF feuse of unde(ned prolems in the onnetion of ewsEsso to the eshe loud hmerD the totl wter mesurement is unfortuntely only prtly exploitle nd hs to e treted refullyF sf the oserved di'erenes etween ewsEsso nd ee re due to )uxes from the hmer wlls tht re ptured y ewsEsso due to the loser proximity to the wllsD these mesurements ould for exmple e used to test the vlidity of the ove desried modeling pproh of wll )uxes nd ould even e used to re(ne the modelF et the time of this writingD 8.6. Summary of Isocloud IQW pigure VFPHX pigure from ur hF vmD ogX gomprison of the temperture dependene of frtiontion ftors derived from the @isotopeA )ux model in the eshe hmer with previously pulished resultsF ink dots represent frtiontion ftors inferred from sygvyh mesureE mentsF reviously experimentl results re shown with dt s symols nd modeling results s lines @solid for experimentl rnges nd dshed for extrpoltionsAF yur results gree with previous pulished dt ut not with the reently proposed inrese of equilirium frtiontion ftors for wter vpor over ieF this ws however work in progress nd ould not e inludedF he mehnisms for supersturtion ould not lerly e identi(ed euse of limittions in the experimentl setEupF wost importntlyD the unertinty in the totl wter mesurement euse of prolems in the ewsEsso smple line mke preise determintion of the isotopi omposition of totl wter impossileF sn dditionD the mesurement of ie phse wter ehind the gs only re)ets portion of the totl ie phseF hue to the inevitle utEo' size of seprted prtilesD smller ie rystls re lost nd re not detetleF hereforeD it is not possile to urtely determine the di'erene etween the isotopi omposition of gs phse wter nd ie phse wter tht would e neessry to further investigte the two possile explntions of supersturtionF o overome these limittionsD for next loud mpignD severl improvements ould e mde nd would led to n even etter result nd etter interompriility of the di'erent instrumentsF ewsEsso should e onneted to the sme outlet s the other two totl wter mesurementsD wf nd eeD in order to eliminte ny unertinty onerning the smpling lotion nd trnsfer of the smple through the extrtion tuingF egulr mesurements should e done t stle onditions inside the loud hmer to lirte the internl isotope mesurements ginst the externl @nd previously lirtedA ypEgie spetrometersF he wvelength rnge of ss should e hnged to the sme rnge s ewsEssoD whih is espeilly importnt for lower tempertures with very low wter onentrtionsF pinllyD regulr lirtions of the ypEgie spetrometers with the yringe xnoliter snjetion IRH 8. Water isotope fractionation in simulated ice clouds glirtion ystem should e mde with two enrihed stndrds pproximtely mthing the isotopi omposition inside the loud hmerF his wyD n dditionl unertinty euse of di'erent isotopi omposition of lirtion nd rel mesurementsD n e elimintedF Conclusion sn the frmework of this thesisD we developed n ypEgie spetrometer tht shows signi(ntly etter performne nd stility thn previous instruments sed on the sme tehniqueF et wter onentrtions round VH ppmvD the preision ws HFV D HFI nd HFP for δ 2 rD δ 18 y nd δ 17 yD respetively with optimum verging time @out QH minAF ith Rs vergingD the preision is IP D IFI nd QFP F sn the optimum mesurement rnge of the instrument t wter onentrtions round TSH ppmvD preisions of HFPV D HFHP nd HFHU n e hieved with verging times of QH to TH minF es limiting ftor of the uryD strong onentrtion dependene of the isotope rtio meE surements ws identi(edF hue to thorough investigtions nd optimiztion of the nlysis proE edureD the min soure of this dependeny ws identi(ed to e onstnt pttern noise in the mesurementsD whih propgtes in the isotope rtios nd eomes espeilly prominent t low sorptionsD orresponding to lower wter onentrtionsF fy ompring the experimentl dt with syntheti sorption spetrD we ould onlude tht pproxF VQ7 of the seline noise is due to slowly hnging strutured noiseF he strutured noise is ssumed to originte from residul ksttering on multiple optil surfes in the em pth nd ould not @yetA e removedF e therefore propose lirtion strtegy with two isotope stndrdsF yne stndrd should e mesured t four di'erent wter onentrtions efore the mesurementD with eh step minE tined for QH min to determine the onentrtion dependeneF sn dditionD the seond stndrd should e mesured t one wter onentrtion to dpt the isotope sleD whih is muh smller orretion thn the orretion for the onentrtion dependeneF efter the mesureE mentD the seond wter stndrd should e mesured t four di'erent wter onentrtions nd the (rst stndrd t only one onentrtionF his wyD the orretion funtion for the unknown smple n susequently lulted s liner omintion of the individul funtions of the two stndrds nd possile drift n e orreted for y the dditionl oneEonentrtion meE surements of the other stndrdD respetivelyF sn this wyD lirtion mesurements re done IRP gonlusion for pproximtely (ve hours per dy nd mesurements of unknown smples n e done for pproximtely the sme time etween the two PFS h lirtionsF sf the wter onentrtion only shows smll vritions during mesurement @no vritions of more thn PHH ppmv nd no wter onentrtions elow VH ppmvAD the numer of onentrtion steps ould e redued to three or even two stepsD thus shortening the time needed for lirtionF ith the in this thesis estlished lirtion nd orretion protoolD the demonstrted uE ry of the mesurements for wter onentrtions ove VH ppmv is etter thn IH for δ 2 rD R for δ 18 y nd S for δ 17 yF he time etween the two lirtions should e su0iently short to redue dditionl unertinties due to drift of the instrumentF fsed on the drift nlE ysis with ellnEerle plotsD we reommend to run lirtions pproximtely every ThF sf mesurements should e done t lower wter onentrtionsD the error mde in the orretion strongly inreses due to n inverse dependeny of the isotope rtios on the wter onentrtionD whih eomes very lrge for drier gs smplesF et SH ppmvD the ury is pproxF QS D V nd IH for δ 2 rD δ 18 y nd δ 17 yD respetivelyF por mesurements of δ 18 y t wter onentrtions s low s S ppmvD we suessfully demonE strted the pplition of modi(ed ypEgie spetrometerD mesuring t UPVT m -1 F ith this modi(ed instrumentD preision etter thn HFP ws demonstrted for δ 18 y t wter onE entrtions elow PH ppmvF sn dditionD due to muh stronger sorption oe0ientsD the wter onentrtion dependeny of the isotope mesurements re muh smller thn in mesurements t UIVR m -1 nd UPHH m -1 F es novel lirtion instrumentD the yringe xnoliter snjetion glirtion ystem @xsgA ws developed nd used for lirtion mesurements in the l nd during severl mesurement mpigns t the eshe loud hmer in urlsruheF e theoretil model ws estlished to etter explin the opertion of the syringe injetion system nd showed good greement with the experimentl resultsF sn prllel mesurements of xsg nd mirodrop injetorD we ould show tht no frtiontion ours in the wter inside the syringe itself nd tht the new system is well dpted for lirtion mesurements t wter onentrtions s low s severl tens of ppmvF pinllyD the ypEgie spetrometer ws suessfully operted during mesurement mpigns in entrti nd t the loud simultion hmer in urlsruheD qermnyF hue to di0ultieswith the lirtion in entrtiD this dt ould not e fully exploitedF roweverD due to its proper funtioning under hrsh onditionsD we were le to show the promising perspetive of using optil spetrometers for isotope mesurements in the oldest region of the plnetF ith the loud hmer experimentsD we were le to show tht the ypEgie tehnique isD fter proper dptionsD ple to mesure wter isotope rtios even t wter onentrtions s low s severl ppm nd ould thus lso e suessfully used for tmospheri studiesD for exmple in the strtosphereF sn the ner futureD more experimentl investigtions will e done in order to redue the wter onentrtion dependene of the ypEgie spetrometerD whih is t the moment the limiting IRQ ftor for higher preision nd ury of the mesurementsF yne possiility tht is going to e studied is the removl of the dditionl referene photo diode nd to extrt this informtion from the mesurement of the signl photodiodeF sn this wyD optil elements in the em pth suh s the em splitterD lens in front of the referene photo diode nd the photo diode itself ould e removedD whih would eliminte prsiti re)etions nd possile optil fringes in the mesurements nd ould result in redued onentrtion dependeneF es it ws shown in the frmework of this thesisD the novel ypEgie spetrometer is well dpted to mesure t very low wter onentrtionsF he instrument n with proper lirtion e used for mesurements under extreme onditions s for exmple enountered in ontinentl entrtiF xext winterD it will proly e prt of n upoming mesurement mpign t the prenh stlin entrti reserh sttion of home gonordi @US°HT9 E IPQ°PI9iAF his mpign will e done in the frmework of the iuropen eserh gounil @igA trting qrnt projet gywfsxsy of eF vndis of vortoire des ienes du glimt et de l9invironnementF et home gonordiD the men ir temperture is round ESHFV°g IRVD whih orresponds t men pressure of round TSH mr to wter mixing rtios s low s TH ppmv ITWF he lE irtion devieD xsgD n e used not only to lirte the ypEgie instrument ut lso otherD eFgF ommerilly villeD instrumentsF st is lso going to e used for the upoming mesurements t home gonordiF he ojetive of these mesurements nd the ig gywfsxsy projet in generl is to estE lish etter desription of the links etween limteD hydrologil yle nd strtospheri inputs over the lst IHH yers in entrtiF por orret use of wter isotopesD it is importnt to etter understnd the reltion etween physil properties suh s temperture nd reltive humidity nd the frtiontion ftorsF pirst mesurements in loud hmer hve thus een done to investigte kineti frtiontion ftors during solid ondenstion t low temperture IUHF purther investigtions will e done to determine wter frtiontion oe0ientsF hese n e used to improve the desription of loud mirophysis in isotopi models nd will thus led to etter understnding of isotope reords in polr ie oresF o omplish the gol of even more stle wter vpor isotope mesurementsD new wter vpor isotope spetrometer sed on the tehnique of yptil peedk prequeny tilized gvity ingEhown petrosopy @yppE ghAIUI is urrently eing developed in this projet to mesure ll three of the wter vpor isotopesD δ 18 yD δ 17 y nd δ 2 rD nd will e employed together with our ypEgie spetrometerF BibliographyI JouzelD t Y Masson-DelmotteD Y CattaniD y Y DreyfusD q Y FalourdD Y Hoff-mannD q Y MinsterD f Y NouetD t Y BarnolaD t wF Y ChappellazD t Y FischerD r Y GalletD t gF Y JohnsenD Y LeuenbergerD w Y LoulergueD v Y LuethiD h Y OerterD r Y ParreninD p Y RaisbeckD q Y RaynaudD h Y SchiltD e Y SchwanderD t Y SelmoD i Y SouchezD Y SpahniD Y StaufferD f Y SteffensenD t F Y StenniD f Y StockerD pF Y TisonD t vF Y WernerD w Y WolffD i FXyritl nd millennil entrti limte vriility over the pst VHHDHHH yersF snX Science (New York, N.Y.) QIU @PHHUAD xoF SVQWD UWQ!T P HoffmannD q Y WernerD w Y HeimannD wX he wter isotope module of the igrew tmospheri generl irultion modelX study on timesles from dys to severl yersF snX J. Geophys. Res. IHQ @IWWVAD xoF hIRD F ITVUI!ITVWT Q RisiD gF Y LandaisD eF Y WinklerD F Y VimeuxD pFX ht ontrols the sptioEtemporl distriution of hEexess nd IUyEexess in preipittionc e generl irultion model studyF snX Climate of the Past Discussions V @PHIPAD xoF TD SRWQ!SSRQ R BaerD hFF Y PaulD tFfF Y GuptaD wF Y O'KeefeD FX ensitive sorption mesureE ments in the nerEinfrred region using o'Exis integrtedEvityEoutput spetrosopyF snX Applied Physics B: Lasers and Optics US @PHHPAD xoF PEQD PTI!PTS S WebsterD ghristopher F Y HeymsfieldD endrew tFX ter isotope rtios hGrD IVyGITyD IUyGITy in nd out of louds mp dehydrtion pthwysF snX Science (New York, N.Y.) QHP @PHHQAD xoF STSID IURP!S T KerstelD iFFF Y IannoneD FF Y ChenevierD w Y KassiD Y JostD rFEtF Y RomaniniD hX e wter isotope @PrD IUyD nd IVyA spetrometer sed on optil feedk vityE enhned sorption for in situ irorne pplitionsF snX Applied Physics B VS @PHHTAD xoF PEQD QWU!RHT IRT fsfvsyqer U DyroffD gF Y FüttererD hF Y ZahnD eFX gompt diodeElser spetrometer sye for highly sensitive irorne mesurements of wterEisotope rtiosF snX Applied Physics B WV @PHIHAD xoF PEQD SQU!SRV V RozanskiD uFX IVF ssotopes in tmospheri moistureF snX AggarwalD rdeep uF @idtFA Y GatD toel F @idtFA Y FroehlichD ulus pF @idtFAX Isotopes in the Water Cycle -Past, Present and Future of a Developing ScienceF PHHSD ghpter IVF ssotopD F PWI!QHI W SolomonD usnX trtospheri ozone depletionX e review of onepts nd historyF snX Reviews of Geophysics QU @IWWWAD xoF QD PUS IH SayresD hvid F Y MoyerD i tF Y HaniscoD pF Y St ClairD t wF Y KeutschD p xF Y O'BrienD e Y AllenD x F Y LapsonD v Y DemuszD t xF Y RiveroD w Y MartinD Y GreenbergD w Y TuozzoloD g Y EngelD q F Y KrollD t rF Y PaulD t fF Y AndersonD t qFX e new vity sed sorption instrument for detetion of wter isotopologues in the upper troposphere nd lower strtosphereF snX The Review of scientic instruments VH @PHHWAD xoF RD HRRIHP II DansgaardD X he undne of IVy in tmospheri wter nd wter vpourF snX Tellus S @IWSQAD xoF RD F RTI!RTW IP EpsteinD Y MayedaD X rition of yIV ontent of wters from nturl souresF snX Geochimica et Cosmochimica Acta R @IWSQAD xoF SD PIQ!PPR IQ CraigD rX ssotopi ritions in weteori tersF snX Science (New York, N.Y.) IQQ @IWTIAD xoF QRTSD IUHP!Q IR DansgaardD X tle isotopes in preipittionF snX Tellus IT @IWTRAD xoF RD RQT!RTV IS JouzelD tF Y MerlivatD vF Y RothD iFX ssotopi study of hilF snX Journal of Geophysical Research VH @IWUSAD xoF QTD SHIS!SHQH IT RisiD gmille Y BonyD ndrine Y VimeuxD prnoise Y DescroixD vu Y IbrahimD four Y LebretonD iri Y MamadouD srhim Y SultanD fenjminX ht ontrols the isotopi omposition of the efrin monsoon preipittionc snsights from eventEsed preipittion olleted during the PHHT ewwe (eld mpignF snX Geophysical Research Letters QS @PHHVAD xoF PRD vPRVHV IU LeeD tungEiun Y PierrehumbertD ymond Y SwannD eigil Y LintnerD fenjmin FX ensitivity of stle wter isotopi vlues to onvetive prmeteriztion shemesF snX Geophysical Research Letters QT @PHHWAD xoF PQD vPQVHI IV KuritaD xoyuki Y NooneD hvid Y RisiD gmille Y SchmidtD qvin eF Y YamadaD riE royuki Y YoneyamaD uunioX sntrsesonl isotopi vrition ssoited with the wddenE tulin ysilltionF snX Journal of Geophysical Research: Atmospheres IIT @PHIIAD xoF hPR fsfvsyqer IRU IW AugustinD vurent Y BarbanteD grlo Y BarnesD iers pF Y BarnolaD ten wF Y BiglerD wtthis Y CastellanoD imilino Y CattaniD ylivier Y ChappellazD terome Y Dahl-JensenD horthe Y DelmonteD frr Y DreyfusD qrielle Y DurandD qel Y FalourdD oni Y FischerD ruertus Y FlückigerD tqueline Y HanssonD wrgret iF Y HuybrechtsD hilippe Y JugieD qérrd Y JohnsenD igfus tF Y JouzelD ten Y Kauf-mannD trik Y KipfstuhlD tosef Y LambertD prie Y LipenkovD ldimir F Y LittotD qeneviève g Y LonginelliD entonio Y LorrainD eginld Y MaggiD lter Y Masson-DelmotteD lerie Y MillerD reinz Y MulvaneyD oert Y OerlemansD tohnnes Y OerterD rns Y OrombelliD qiuseppe Y ParreninD prederi Y PeelD hvid F Y Pe-titD tenEoert Y RaynaudD hominique Y RitzD gtherine Y RuthD rs Y SchwanderD tko Y SiegenthalerD rs Y SouchezD olnd Y StaufferD fernhrd Y SteffensenD torgen F Y StenniD frr Y StockerD homs pF Y TabaccoD sgnzio iF Y UdistiD oerto Y Van De WalD oderik F Y Van Den BroekeD wihiel Y WeissD terome Y WilhelmsD prnk Y WintherD tnEqunnr Y WolffD iri F Y ZucchelliD wrio Y MembersD ipi gFX iight glil yles from n entrti ie oreF snX Nature RPW @PHHRAD xoF TWWPD TPQ!TPV PH Masson-DelmotteD F Y HouD F Y EkaykinD eF Y JouzelD tF Y AristarainD eF Y BernardoD F F Y BromwichD hF Y CattaniD yF Y DelmotteD wF Y FalourdD F Y FrezzottiD wF Y GalléeD rF Y GenoniD vF Y IsakssonD iF Y LandaisD eF Y HelsenD wF wF Y HoffmannD qF Y LopezD tF Y MorganD F Y MotoyamaD rF Y NooneD hF Y OerterD rF Y PetitD tF F Y RoyerD eF Y UemuraD F Y SchmidtD qF eF Y SchlosserD iF Y SimõesD tF gF Y SteigD iF tF Y StenniD fF Y StievenardD wF Y BroekeD wF F dF Y WalD F F F dF Y BergD F tF dF Y VimeuxD pF Y WhiteD tF F gFX e eview of entrti urfe now ssotopi gompositionX yservtionsD etmospheri girultionD nd ssotopi wodelingBF snX Journal of Climate PI @PHHVAD xoF IQD QQSW!QQVU PI GoffD tF eFX turtion pressure of wter on the new kelvin sleF snX Trans. Am. Soc. Heating Air-Cond. Eng. TQ @IWSUAD F QRU!QSR PP GoffD tF eFX Saturation pressure of water on the new Kelvin scale. In Humidity and moisture: Measurement and control in science and industryF einhold ulishingD xew orkD eD IWTS PQ MurphyD hF wF Y KoopD FX eview of the vpour pressures of ie nd superooled wter for tmospheri pplitionsF snX Quarterly Journal of the Royal Meteorological Society

Climate

  Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate ChangeF gmridgeD nited uingdom nd xew orkD xD eF X gmridge niversity ressD PHHUF ! WWT F IRI JouzelD t Y Masson-DelmotteD X leolimtesX wht do we lern from deep ie oresc snX Wiley Interdisciplinary Reviews-Climate Change I @PHIHAD xoF SD F TSR!TTW IRP HansenD qF Y AspmoD uF Y BergD F Y EdvardsenD uF Y FiebigD wF Y KallenbornD F Y KrognesD F Y LunderD gF Y StebelD uF Y SchmidbauerD xF Y SolbergD F Y YttriD uFiFX etmospheri monitoring t the xorwegin entrti sttion rollX mesurement progrmme nd (rst resultsF snX Polar Research PV @PHHWAD xoF QD QSQ!QTQ IRQ Trigas FIX No TitleF http://www.trigasfi.de/pdf/Sonic-Nozzle-Brochure.pdfF ersionX PHIR IRR HoritaD t Y WesolowskiD ht tFX viquidEvpor frtiontion of oxygen nd hydrogen isotopes of wter from the freezing to the ritil tempertureF snX GEOCHIMICA ET COSMOCHIMICA ACTA SV @IWWRAD xoF ITD QRPS!QRQU IRS MookD illem qFX I E sntrodution E heory D methodsD reviewF snX Environmental Isotopes in the Hydrological Cycle -Principles and ApplicationsF snterntionl etomi inergy egeny nd nited xtions idutionlD ienti( nd gulturl yrgniztionD PHHID F I!ITS IRT DraxlerD FF Y RolphD qFhFX HYSPLIT(HYbrid Single-Particle Lagrangian Integrated Trajectory) Model access via NOAA ARL READY WebsiteF (http://ready.arl.noaa. gov/HYSPLIT.phpF ersionX PHIQ IRU DraxlerD FF Y HessD qFhFX en overview of the rvsR modeling system of trjetoriesD dispersionD nd depositionF snX Aust. Meteor. Mag. RU @IWWVAD F PWS!QHV IRV Institut Polaire Francais -Dome ConcordiaF http://www.institut-polaire.fr/ipev/ bases_et_navires/station_concordia_dome_c IRW KellerD vind wF Y LazzaraD wtthew eF Y ThomD tonthn iF Y WeidnerD qeorge eF Y StearnsD ghrles FX entrti eutomti ether ttion ht for the lendr yer PHHWF @PHIHA ITH fsfvsyqer ISH KrämerD w Y SchillerD g Y AfchineD e Y BauerD Y GenschD s Y MangoldD e Y SchlichtD Y SpeltenD x Y SitnikovD x Y BorrmannD Y ReusD w de Y SpichtingerD X se supersturtions nd irrus loud rystl numersF snX ATMOSPHERIC CHEMISTRY AND PHYSICS W @PHHWAD F QSHS!QSPP ISI KärcherD fX upersturtionD dehydrtionD nd denitri(tion in erti irrusF snX ATMOSPHERIC CHEMISTRY AND PHYSICS S @PHHSAD F IUSU!IUUP ISP KorolevD elexei F Y MazinD sli FX upersturtion of ter por in gloudsF snX Journal of Atmospheric Science TH @PHHQAD xoF PRD F PWSU!PWUR ISQ MoyerD iFtFX snterntionl gollortion in ghemistryX smproving understnding of ie nuletion nd growth inhiition mehnisms vi new isotopi trer studies in the eshe erosol hmerF snX Application for a Research Grant: Project Description @PHIHA ISR GallavardinD tF Y FroydD u hF Y LohmannD Y MoehlerD y Y MurphyD h wF Y CziczoD h tFX ingle prtile lser mss spetrometry pplied to di'erentil ie nuletion experiments t the eshe ghmerF snX Aerosol Science and Technology RP @PHHVAD F UUQ! UWI ISS FaheyD hF F Y GaoD F F Y MöhlerD yFX ummry of the equs ter por snteromprison X tti ixperimentsF PHHW @ytoerAF ! ienti( reportF ! IHP F IST HiranumaD xF Y KohnD wF Y PekourD wF F Y NelsonD hF F Y ShillingD tF iF Y CziczoD hF tFX hroplet tivtionD seprtionD nd ompositionl nlysisX lortory studies nd tmospheri mesurementsF snX Atmospheric Measurement Techniques R @PHIIAD xoF IHD PQQQ!PQRQ ISU BoulterD t iF Y CziczoD h tF Y MiddlebrookD e wF Y ThomsonD h F Y MurphyD h wFX hesign nd erformne of umped gounter)ow irtul smptorF snX Aerosol Science and Technology RH @PHHTAD xoF IID F WTW!WUT ISV KulkarniD qourihr Y PekouraD wikhil Y AfchinebD ermin Y MurphycD hniel wF Y CziczoaD hniel tF Y PekourD wikhil Y AfchineD ermin Y MurphyD hniel wF Y CziczoD hniel tFX gomprison of ixperimentl nd xumeril tudies of the erformne ghrteristis of umped gounter)ow irtul smptorF snX Aerosol Science and Technology RS @PHIIAD xoF QD QVP!QWP ISW MöhlerD yF Y BüttnerD F Y LinkeD gF Y SchnaiterD wF Y SaathoffD rF Y StetzerD yF Y WagnerD F Y KrämerD wF Y MangoldD eF Y EbertD F Y SchurathD FX i'et of sulfuri id oting on heterogeneous ie nuletion y soot erosol prtilesF snX Journal of Geophysical Research IIH @PHHSAD xoF hIID hIIPIH fsfvsyqer ITI ITH FaheyD hF F Y GaoD FEF Y MöhlerD yF Y SaathoffD rF Y SchillerD gF Y EbertD F Y KrämerD wF Y PeterD F Y AmaroucheD xF Y AvalloneD vF wF Y BauerD F Y BozókiD F Y ChristensenD vF iF Y DavisD F wF Y DurryD qF Y DyroffD gF Y HermanD F vF Y HunsmannD F Y KhaykinD F wF Y MackrodtD F Y MeyerD tF Y SmithD tF fF Y SpeltenD xF Y TroyD F pF Y VömelD rF Y WagnerD F Y WienholdD pF qFX he equsEI interomprison of tmospheri wter vpor mesurement tehniquesF snX Atmospheric Measurement Techniques Discussions U @PHIRAD xoF RD QISW!QPSI ITI SaathoffD rFX No TitleF PHIQ ITP LambD ur hF Y ClouserD fen Y SarkozyD vszlo Y StutzD iri Y KühnreichD fenjmin Y LandsbergD tnek Y HabigD tn Y HiranumaD xruki Y WagnerD teven Y EbertD olker Y KerstelD irik Y MöhlerD yttmr Y SaathoffD rrld Y MoyerD ilisethX hiret wesurements of ssotopi prtiontion ptors of ter por over se for PQS uF snX Goldschmidt conference @PHIQA ITQ Ellehø jD wds hFX Ice-vapor equilibrium fractionation factorD xiels fohr snstituteD hissFD PHII ITR MatsuoD do Y KuniyoshiD rideko Y MiyakeD suoX por pressure of ie ontining dPoF snX Science IRS @IWTRAD xoF QTQWD F IRSR!IRSS ITS JohanssonD wF Y Holmberg.D uF iFX eprtion of hevy wter in phse equiliri involving pure wter or sltEwter systemsF snX Acta Chemica Scandinavica PQ @IWTWAD xoF QD F UTS ITT Van HookD F elexnder FX por pressures of the isotopi wters nd iesF snX The Journal of Physical Chemistry UP @IWTVAD xoF RD F IPQR!IPRR ITU PupezinD tovn hF Y JakliD qyorgy Y JancsoD qor Y Van HookD F eFX por pressure isotope efet in queous systemsF iF wterEwterEdP @ETRFdegF to IHHFdegFA nd fsfvsyqer ISR wterEwterIVEH @EIUFdegF to ITFdegFAF ie nd liquidF iiF lkli metl hloride solution in wter nd wterEdP @ESFdegF to IHHFdegFAF snX The Journal of Physical Chemistry UT @IWUPAD xoF SD F URQ!UTP ITV MéheutD werlin Y LazzeriD wihele Y BalanD itienne Y MauriD prnesoX iquiliE rium isotopi frtiontion in the koliniteD qurtzD wter systemX redition from (rstE priniples densityEfuntionl theoryF snX Geochimica et Cosmochimica Acta UI @PHHUAD xoF IQD F QIUH!QIVI ITW Antarctic Meteorology Research at the University of Wisconsin-Madison (AMRC & AWS)F http://amrc.ssec.wisc.edu/data/view-data.php?action=list&product= surface/plotF ersionX PHIR IUH CasadoD wthieu Y CauquoinD elexndre Y LandaisD emelle Y LandsbergD tnek Y KerstelD irik Y DoussinD tenEprnçoisX ixperimentl determintion for kineti frE tiontion during solide ondenstion t low temperture nd theoretil frmeworkF snX Geophysical Research Abstracts, Vol. 16D PHIR IUI BurkartD tohnnes Y RomaniniD hniele Y KassiD mirX yptil feedk stilized lser tuned y singleEsidend modultionF snX Optics letters QV @PHIQAD xoF IPD PHTP!R IUP HarrisD tF F Y StockerD rFX pheril egment @pheril gpAF snX Handbook of Numerical Analysis. Special Volume: Foundations of Computational MathematicsF IWWVD F IHU IUQ NooneD hF Y RisiD gF Y BaileyD eF Y BerkelhammerD wF Y BrownD hF F Y BuenningD xF Y GregoryD F Y NusbaumerD tF Y SchneiderD hF Y SykesD tF Y VanderwendeD fF Y WongD tF Y MeillierD F Y WolfeD hFX hetermining wter soures in the oundry lyer from tll tower pro(les of wter vpor nd surfe wter isotope rtios fter snowstorm in golordoF snX Atmospheric Chemistry and Physics IQ @PHIQAD xoF QD ITHU!ITPQ IUR BolotD wF Y LegrasD fF Y MoyerD iF tFX wodelling nd interpreting the isotopi omposition of wter vpour in onvetive updrftsF snX Atmospheric Chemistry and Physics IQ @PHIQAD xoF ITD UWHQ!UWQS IUS MoyerD iFtF Y SayresD hFF Y EngelD qFF Y St. ClairD tFwF Y KeutschD pFxF Y AllenD xFF Y KrollD tFrF Y AndersonD tFqFX hesign onsidertions in highEsensitivity o'Exis integrted vity output spetrosopyF snX Applied Physics B WP @PHHVAD xoF QD RTU!RUR IUT RomaniniD hF Y LehmannD uF uFX ingEdown vity sorption spetrosopy of the very wek rgx overtone nds with sixD sevenD nd eight strething quntF snX The Journal of Chemical Physics WW @IWWQAD xoF WD TPVU IUU EhlersD trik Y SilanderD ssk Y WangD tunyng Y AxnerD yveX pierElserEsed noiseEimmune vityEenhned optil heterodyne moleulr spetrometry instrumentE tion for hopplerErodened detetion in the IH¢â¢9IPâ¿â¿m¢â¢9Iâ¿rz¢â¢9IGP regionF snX Journal of the Optical Society of America B PW @PHIPAD xoF TD IQHS IUV LaurentD Y ClaironD e Y BreantD gX prequeny noise nlysis of optilly selfEloked diode lsersF snX Quantum Electronics, IEEE . . . PS @IWVWAD xoF T IUW GianfraniD v Y GagliardiD q Y BurgelD w vn Y KerstelD i FX ssotope nlysis of wter y mens of nerEinfrred dulEwvelength diode lser spetrosopyF snX Optics Express II @PHHQAD F ISTT!for eir eserh yeEsgy y'Exis sntegrted gvity yutput petrosopy ypEgie yptil peedk gvity inhned esorption petrosopyyppEgh yptil peedk prequeny tilized gvity ingEhown petrosopy fFPX @A he droplet is ssumed to hve n enrihed surfe with volume V s (t) nd ore volume V c (t) with isotopi omposition s the wter in the reservoir @A he di'erent volumes of wter in the model pprohF ter from the reservoir is injeted to the ore volume V c D trvels into the surfe lyer volume V s nd is evportedF he )ow from the reservoir to the ore is Φ 0 D the )ow from the ore to the surfe lyer Φ C D nd the )ow of evported wter Φ e F fefore we look in detil into the ehvior of the isotopesD we investigte the ehvior of totl wter in this modelD whih llows us to derive n expression for the droplet sizeD s well s the evported wter )owD s funtion of timeF gomining the ltter with the dry ir )owD we then otin n expression for the wter volume mixing rtio s funtion of timeF he volume of the droplet equls the )ow towrds the droplet minus the )ow out of the dropletF sn disrete time one otins the following integrtion formulX V drop (t + ∆t) = V drop (t) + (Φ 0 (t) -Φ e (t)) h ≤ 2r ith r 2 = r 2 0 + r 2 d nd r d = r -h @fF (gure fFIAD A S n lso e written s A S = π r 2 0 + h 2 @fFSA e now wnt to express the p height in terms of the droplet volume V drop F tht the evportion rte Φ e (t) is proportionl to the @exposedA surfe of the wter dropletX Φ e (t) := k e • A s (t) @fFVA with k e onstnt evportion ftorF ith this nd the injetion rte Φ 0 (t)D the itertion step yields

  wter isotope pleothermometer UU nd for the understnding of irrus loud formtion nd troposphereEstrtosphere exhnges QD IURD respetivelyF ntil nowD smll numer of optil instruments hve een developed with the im to mesure in situ wter isotopes with high preision t very low wter undnes S!UD IHD VQD IIVD IUSF nfortuntelyD resolving the detils of isotope frtiontion e'ets t these low wter onenE trtions requires even higher levels of sensitivity nd preisionF e stndrd qunti(tion of the sensitivity of n sorption spetrometer is given y the noise equivlent sorption sensitivity @xieA IUSD IUTD whih gives the minimum detetle E sorption per unit pth length normlized to the mesurement rte w @the inverse of the time required to reord full spetrumAF sf δI represents the unertinty @1σA of the deteted light trnsmission of intensity I over n e'etive sorption pth length L e D the xie is given

  IUS he e'et of inresing F is quite di'erent in the se of optilEfeedk vityEenhned E sorption spetrosopy @ypgieAD s this tehnique enles optiml nd rpid oupling of the lser rdition to the trnsmission modes of the highE(nesse vity VIF sn ftD in this vetter we demonstrte n ypgie spetrometer with F ≈ 144, 000F st relizes high level of light injetion nd vityEthroughput nd gin in sensitivity proportionl to the (nesse for given mesurement timeF sn dditionD we were le to inrese T opt ompred to previous lower (nesse setupF sn order to reord sorption spetr with the ypgie tehniqueD lser is pproximtely modeEmthedD then optilly loked to suessive longitudinlD iw 00 modes of threeEmirror Eshped vityF his geometry returns portion of the light resonting inside the vity s optil feedk to the lser soureF et the sme timeD it voids un(ltered feedk of the diret re)etion from the input mirrorD s desried inD eFgFD VIF he forementioned high light throughput is predominntly due to nrrowing of the lser linewidth to elow the vity trnsmission mode width @∼ p/FA VID VPD IUVF husD ypgieD in ontrst to other gie or gh tehniquesD does not su'er from n indequte light trnsmission t very high mirror re)etivityF sn ftD no diminution of the light intensity fter the vity is oservedD despite sevenEfold ugmenttion of FF he instrument presented in this vetter is ompred to previous instrument developed in our groupF his older instrumentD lled isotope rtio infrred spetrometer @ssA prtiipted in irorne mpigns to study the upper troposphere nd lower strtosphere nd is desried in detil in TD VQD IIVF ss ws equipped with highEre)etivity mirrors resulting in ringEdown time of τ 0 = 21 µs nd xie of 4 × 10 -10 m -1 rz -1/2 F he new highE(nesse isotope rtio instrument @ripsA is equipped with mirrors of re)etivity 99.99897 @I E a II ppm nd roughly equl losses nd trnsmissionY vyerte qmrAD resulting in τ 0 = 150 µsF he (nesse of Eshped vity with rms of length L 1 nd L 2 is given yF = πR/(1 -R 2 ) = πcτ 0 /(L 1 + L 2 )VPF sn this seD with L 1 = L 2 = 489 mmD F ≈ 144, 000 @ stndrd liner vity of the sme externl length using the sme mirrors would hve F = 288, 000D nd twie s lrge pD for the sme ringEdown timeAF es ssD rips mesures the four wter vpor isotopologues r rnge ner UIVR m -1 F e delierte hoie ws mde to work in the nerEinfrred region of the spetrumD where stteEofEtheErt mirror otings llow for more thn ten times inrese in (nesse ompred to the midEinfrred @wsA regions round PFU nd TFU µmF he ssoited longer L e is expeted to outweigh the roughly one order of mgnitude higher E sorption nd strength in the wsD without even onsidering the lower performne of ws detetors nd other optil omponentsF pigure gFI shows typil rips spetrumF et wter onentrtions elow SHH ppmvD the xie is typilly 6 × 10 -11 m -1 rz -1/2 D n improvement y ftor of lmost U ompred to ss whih is equl to the rtio of the (nessesF glerlyD the penlty of the slower sn rte is not s severe s might hve een expetedD mostly euse the sn time is still used e'etively @see IUT C. Optics Letter elowA to etter de(ne the vity mode trnsmission mxim needed to lulte the sorption spetrumF husD the produt of the (rst nd lst ftors in iqF gFI remins unhngedD nd the improvement in xie ppers to e determined y the inrese in L e F elthough in oth instruments no fringes re visile on the spetrum selineD we nnot ompletely exlude tht prt of the improvement is due to redution of the fringes underneth the noise strutureF st is noted tht our xie vlues re sed on the w noise of the (t residuls of single spetrumF husD they would lso inlude possile e'ets of (t imperfetions nd fringesF sn the followingD we rie)y disuss the improvements tht were neessry to ommodte the pigure gFIX ingle spetrum reorded with rips t SHH ppmv r 2 16 y nd P rz mesurement rteF he w of the residuls is 8 × 10 -11 m -1 F new ultrhighE(nesse vity nd inrese T opt D nd we present our (rst results illustrting instruE ment stility nd performneF rips is mounted in thermlly insulted IW inF rk housingF he Eshped vity hs n internl volume ∼PS mv tht is eletroEpolished nd oted with

  tetle IIVF pigure gFP shows n ellnEerle plot of the r 2 18 yD r 2 17 y nd rh 16 y isotope rtios from mesurements t the lowest smple onentrtion of PH ppmvF he (gure lso inE ludes the elln devitions for the deuterium exess d = δ 2 H -8 δ 18 O IR nd the 17 OEexess = ln(1 + δ 17 O) -0.528 ln(1 + δ 18 O) RR whihD howeverD re prtilly indistinguishle from the δ 2 r nd δ 17 y elln devition urvesD respetivelyF hependent on the wter onentrtionD the optimum integrtion time for the isotope rtio deE termintion is up to ∼UH minF por longer integrtion timesD drift degrdes the preisionF he IUV

  in the denomintor ounts for the two equivlent positions of the hydrogen tom in the wter moleuleF st is ommon to report isotope rtios not in solute numers ut in respet to referene smple or stndrdF yne of the resons for this is tht the solute rtios re in generl less relevnt thn hnges in the rtios euse of phse trnsitions or moleulr hngesF enother reson is tht most of the instruments ple to mesure isotope undnes re not suitle to mesure solute rtios ut rely on the omprison with referene smple PSF es the hnge of the isotope rtios during the trnsitions is often very smllD the hnge of the isotope rtio of smple e is normlly reported reltive to the rtio of referene smple r s permil devitionX

	1.2. Isotopes	S
	he ftor P
	1.2.1	Isotope ratios
	ssotope undnes re generlly reported s rtio of the less undnt isotope nd the most
	undnt isotopeX
	R =	undne of rre isotope undne of undnt isotope	@IFSA
				@IFTA

he isotope rtio normlly hs supersript efore the rtio symol to indite whih isotope

is onsidered PSF por exmpleX 2 R(H 2 O) = [HD 16 O] 2[H 16 2 O]

  hese equtions re vlid for -34 °g ≤ T ≤ 0 °g for α ice-vapor ( 18 yG 16 y) nd 0.75 °g ≤ ≤ 91.6 °g for the phse hnge liquidEvporF uineti frtiontion on the other hnd desries n irreversile proessD with removl of moleules from the vpor phse eFgF euse of di'usionF sf one ssumes tht moleules re

	1.2. Isotopes					U
	formulted y wjoue QSD QTX
	ln α liquid-vapor ( 2 H/ 1 H) = -52.612 • 10 -3 -	76.248	+	24.844 • 10 3 2	@IFIIA
	ln α ice-vapor ( 18 O/ 16 O) = -28.224 • 10 -3 +	11.839			@IFIPA
	ln α liquid-vapor ( 18 O/ 16 O) = -2.06667 • 10 -3 -	0.4156	+	1.137 • 10 3 2	@IFIQA
	with in uelvinF

removed due to di'usion from the oundry lyer etween liquid nd vpor phseD the kineti frtiontion ftor n e expressed s QPD QUD QVX

  The optical alternative: Stable Isotope Ratio Infrared Spectroscopy

IS gomining equtions PFP nd PFQ we getX

  with the vity modes k nd mD τ k the ringEdown time of mode kD nd H k the mesured intensity rtio t mode kF e derivtion of this reltion n e found in VIF his pproximtion is very good under typil gie onditionsD nd even in the limit of reltively strong sorptionF sn

	PT		2. Measurement of isotopes
	viner gvity	Eshped vity
	p	c/(2L)	c/2(L 1 + L 2 )
	ringEdown time empty
	vity
	(a)		(b)
	pigure PFUX ixemplry ypEgie signlD A signl over the entire lser sn A t the end of eh
	sn the lser is interrupted to reord h event to onvert the reorded spetr to sorption
	sle
	tle PFID the most importnt hrteristi dimensions like the p nd pinesse re ompred
	for liner vity nd Eshped vityF

  very long residene times for eh single mode in the vityD snning frequeny of IFWT spetr per seond ws hosenD orresponding to pproximtely QFS ms per single modeF he snning frequeny is thus ftor three smller thn in the predeessor ssF roweverD

	PV QH 3.4. Data acquisition and storage	2. Measurement of isotopes 3. OCEAS instrument design QI
	1/ H max (m) for ll modes m nd then multiplying y the ftor (γ k /c) H max (k) determined of mirrors for the wsD this would lso hve required the use of less sensitive photodetetorsF 3.4 Data acquisition and storage
	y the ringEdown mesurement t mode kF st should e underlined tht the sorptionEsle he gin of stronger trnsitions would thus hve een neled out or even overompensted y
	lirtion proedure n lso e performed in the presene of intrvity sorptionF he liE rtion of gie mesurements in solute sorption units does not require mesurement of the ringEdown time for n empty vityF en investigtion of the ury of the normliztion these disdvntgesF he entire instrument is ontrolled y g progrm on ewWEsed miroEontroller @eE Chapter 3 sn our instrumentD the photodetetors re snqes detetors @rmmtsuA wired in the k wivAD whih is lso used for the dt quisition in omintion with nlogGdigitl onverterF OCEAS instrument design of the detetorD whih redues the risk of optil fringes indued y prsiti re)etions on the gommunition with the ewW is estlished vi n ithernet onnetion with vview @xE
	is disussed in detil in VIF wiresF tionl snstrumentsA sed progrmD whih is lso used to ontrol the instrumentF ht nlysis por typil ypEgie vity with ringEdown time of 20 µsD the reltive error due to the norE o orret the mesurements for wter sorption ourring outside of the gs ellD the pth is done onEline with the sme vview progrm in omintion with g sed nlysis progrm
	mliztion proedure is smller thn IHH ppm for vity trnsmissions lrger thn IH7 of the lengths outside the vity for referene nd signl photodiode were mthedF his eomes inorporting the winuit lirry of gix VSF he signl of the two photodiodes is digitized
	mximum vlue @H > 0.1AF his would orrespond to n sorption oe0ient of 4 × 10 -6 Gm sn this hpterD the ypEgie lser spetrometerD ss @petromètre snfrrouge des pports espeilly importnt when the smple mesured in the gs ell is muh drier thn the mient y IT it eGh onverter with TH HHH points per hnnelF hue to the high ringEdown timesD
	orD onsidering typil noise level of 4 × 10 -10 GmD to dynmi rnge of four dedesF por ssotopiquesAD developed within the frmework of this thesisD is desriedF e (rst ypEgie irF whih result in
	higher (nesse vity suh s the one used in our spetrometerD the ury of the normlizE spetrometer for wter vpor isotope mesurements ws introdued y uerstel et lF in PHHT TD
	tion is even etterF por vity trnsmissions lrger thn S7D the reltive error for vity with n improved version ws desried y snnone et lF in PHHW VQF ith the novel spetrometer ssD we spei(lly imed for n instrument le to mesure wter vpor isotopes in very dry ringEdown times of IQH µs would e smller thn SH ppmF onditions with wter onentrtions well elow SHH ppmv s enountered in entrti nd 3.2 Mechanical layout
	the upper tmosphereF his requires n instrument with muh higher sensitivity nd stility
	nd ould e hieved with the design detiled in the followingF sn dditionD we refer to our he instrument is mounted in thermlly insulted luminum singD whih hs volume of
	pulition in yptis vetters VRD whih n e found in ppendix gF lese note tht for the pproxF RS l nd weight of PS kg nd is thus esily trnsportleF he ore of the spetrometer
	purpose of the yptis vetter pulitionD the instrument developed in this work nd referred to is n dditionlly insulted tringulr se mounted on four metlli springs on whih the optil
	s ss throughout this entire thesis ws nmed ripi @for righ pinesse petrometerA to o'er setEup is instlledF he Eshped vity onsists of two rms of SH m under n ngle of HFWR°F
	more interntionl nmeF yther thn previous versionsD the gs ell is other thn in previous versions now mhined from
	single stinless steel loD whih redues the risk of leksF
	3.1 Optical Layout 3.3 Flow system
	he lser soure used in the lser spetrometer ss isD s in the predeessor ssD distriuted
	feedk @hpfA diode lser @otined from either vsergomponents or xnoplusA with typE en importnt ftor in)uening the response time of n instrumentD is the soElled memory
	il mximl output power of IHmF por the di'erent spetrl regions @disussed in detil in e'etF hue to for exmple dsorption of wter to the wlls of tuing nd vity of the instrument
	setion QFTAD vrious lsers were usedF or smll ded volumes tht re not e0iently exhnged with new gsD the time response of n
	he vity mirrors @from vyerte qmrA hve rdius of I m nd wedge of I°F ith n optil spetrometer n sometimes e in the order of severl minutesF empty vityD these mirrors yield ringEdown time of ISH µs @t UIVR m -1 D whih is more thn o redue the memory of our systemD the eletropolished stinless steel of the gs ell is now
	ftor seven higher thn in previous instruments nd requires n even more preise lignment dditionlly oted with )uoroliphti polymer @gytonix pluoroel VHHeAF
	of the optil setEupF he ringEdown time orresponds to re)etivity of WWFWWVW7 @IEaII feuse of the very low wter onentrtionsD speil ttention ws pid to the gs inlet system
	ppmA nd leds to vity with (nesse of pproxF IRRDHHH @ stndrd liner vity of the to redue memory e'etsF ell inlet tuing is oted y9frin tuingD nd iltek treted inlet
	sme externl length using the sme mirrors would hve F ≈ 288, 000AF his high (nesse results (lter @estekA is used to protet the system ginst ontmintion from lrger prtilesF he
	in n e'etive pth length of nerly RS km nd is neessry to e sensitive enough to mesure pressure is regulted to QS mr y iltek treted pressure ontroller @fronkhorstA t )ow
	he totl loss oe0ient γ k n e determined experimentlly y (tting exp(-γ k t) to ringE t very low wter onentrtionsF rte of pproxF ISH smF he gs ell hs hnnels with dimeter of S mmD whih results in
	down eventD whih n e produed y n rupt interruption of the lser one the mximum injetion for mode k hs een rehedF he gie spetrum n then e otined in soE snsted of using very high re)etivity mirrorsD it would hve een possile to hnge from the volume of IVFT m nd therefore in gs exhnge time of only HFIV sF nerEinfrred into the midEinfrred @wsA t PFU µmD whih would hve resulted in trnsitions huring in (eld deployment of the instrumentD dditionl y9frien tuing is used for the inlet nd
	lute sorption unitsD prt from n o'set due to the empty vity losses @γ 0 AD y lulting tht re pproxF ftor IH strongerF roweverD prt from the urrently still lower re)etivities is temperture stilized to pproximtely 50°g with n utoEregulting heting nd @rorstAF

insted of one ringEdown event per seondD the lser is now interrupted for pproximtely QFS ms @RHH dt pointsA t the end of eh snF rousekeeping dt suh s vity temperture nd pressure re reorded with IP it nd verged over IH onseutive quisitions efore eing written to (leF

  sn (gure RFIHD typil ringEdown event reorded t the end of eh lser snD is shownF por the nonElinerity hekD we verged over QH susequent ringEdown events to further redue the noise on the mesurementF sn (gure RFIHD the (t of n ordinry exponentil dey nd the

residul of this (t re shownF he redued hiEsqure of the (t is χ 2 red = 8.8 × 10 -9 nd gives ringEdown time of τ = 119.25 ± 0.01 µsF he residul of the (t is uniform nd does not show ny devitions during the ringEdown eventF sn (gure RFIHD the sme ringEdown event (t with n dditionl qudrti term @eqution RFIHA is givenD ssuming nonElinerity of the photo detetorsF he (t hs redued hiEsqure of

  eh isotopologueD the funtion of eqution @SFQA is (t independently to the two lirtion mesurements of qRV nd qSHF he dt is weighted with the stndrd error of the dt pointsF he (t is shown in (gure SFTD the resulting prmeters re given in tle SFIF he

	TR			5. Data Corrections and Calibration
	tndrd ssotope qRV δ 2 r δ 18 y δ 17 y	δ 0 -58 ± 5 -12 ± 2 -9 ± 3	b 3619 ± 459 -416 ± 125 0.021 ± 0.004 m -0.02 ± 0.01 -1302 ± 248 0.018 ± 0.007
	qSH	δ 2 r δ 18 y δ 17 y	-282 ± 7 -38.8 ± 0.8 -24 ± 2	7489 ± 504 -529 ± 64 -1069 ± 145 0.013 ± 0.005 0 ± 0.02 0.01 ± 0.002
				t
	results re given in tle SFI

por

  PU De WitD tFgF Y StraatenD gFwF vn dF Y MookD FqX hetermintion of the esolute rydrogen ssotopi tio of wy nd veF snX Geostandards Newsletter R @IWVHAD xoF ID F QQ!QT PV BaertschiD FX esolute IVy gontent of tndrd wen yen terF snX Earth and Planetary Science Letters QI @IWUTAD F QRI!QRR PW LiD F Y NiD fF Y JinD hF Y ChangD FvX wesurement of the esolute eundne of yxygenEIU in wyF snX Chinese Science Bulletin QQ @IWVVAD F ITIH!ITIQ QH WiseD FeF Y WattersD FvFX eport of snvestigtion eferene wterils VSQSD VSQTD VSQU G xtionl snstitute of tndrds 8 ehnologyF PHHSF ! ienti( report QI GonfiantiniD F Y RozanskiD uF Y StichlerD FX snterlirtion of invironmentl ssotope wesurementsX he rogrm of the snterntionl etomi inergy egenyF snX MerlivatD vilineX heuterium nd oxygen IV in preipittionX wodeling of the isotopi e'ets during snow formtionF snX Journal of Geophysical Research: . . . VW @IWVRAD xoF hUD IIURW RH MerlivatD vilineX woleulr di'usivities of rPITyD rhITyD nd rPIVy in gsesF snX The Journal of Chemical Physics TW @IWUVAD xoF TD PVTR RI LoriusD gF Y MerlivatD vF Y HagemannD FX rition in the men deuterium ontent of preipittions in entrtiF snX Journal of Geophysical Research UR @IWTWAD xoF PVD UHPU!UHQI RP JouzelD ten Y MerlivatD viline Y LoriusD gludeX heuterium exess in n ist entrti ie ore suggests higher reltive humidity t the oeni surfe during the lst glil mximumF snX Nature PWW @IWVPAD xoF SVVSD TVV!TWI RQ VimeuxD p Y MassonD Y JouzelD t Y StievenardD w Y PetitD tX qlilEinterglil hnges in oen surfe onditions in the southern hemisphereF snX NATURE QWV @IWWWAD xoF TUPTD RIH!RIQ RR BarkanD iugeni Y LuzD fozX righ preision mesurements of IUyGITy nd IVyGITy rtios in rPyF snX Rapid communications in mass spectrometry : RCM IW @PHHSAD xoF PRD QUQU!RP RS BarkanD iugeni Y LuzD fozX hi'usivity frtiontions of rP@ITAyGrP@IUAy nd rP@ITAyGrP@IVAy in ir nd their implitions for isotope hydrologyF snX Rapid communications in mass spectrometry : RCM PI @PHHUAD xoF IVD PWWW!QHHS RT LandaisD emelle Y BarkanD iugeni Y LuzD fozX eord of δ IV y nd IU yEexess in ie from ostok entrti during the lst ISHDHHH yersF snX Geophysical Research Letters QS @PHHVAD xoF PD vHPUHW RU GatD tF F Y MatsuiD iFX etmospheri wter lne in the emzon sinX en isotopi evpotrnspirtion modelF snX Journal of Geophysical Research WT @IWWIAD xoF hUD IQIUW RV BermanD ilen pF Y LevinD xomi iF Y LandaisD emelle Y LiD huning Y OwanoD homsX wesurement of δIVyD δIUyD nd IUyEexess in wter y o'Exis integrted vity output spetrosopy nd isotope rtio mss spetrometryF snX Analytical chemistry VS @PHIQAD xoF PID IHQWP!V RW SteigD iF tF Y GkinisD F Y SchauerD F tF Y SchoenemannD F F Y SamekD uF Y HoffnagleD tF Y DennisD uF tF Y TanD F wFX glirted highEpreision IUyexess mesurements using lserEurrent tuned vity ringEdown spetrosopyF snX Atmospheric Measurement Techniques Discussions T @PHIQAD xoF TD IHIWI!IHPPW SH WinklerD F Y LandaisD eF Y SodemannD rF Y DümbgenD vF Y PriéD pF Y Masson-DelmotteD F Y StenniD fF Y JouzelD tFX heglition reords of IUyEexess in ist entrtiX relile reonstrution of oeni reltive humidity from ostl sitesF snX Climate of the Past Discussions U @PHIIAD xoF QD IVRS!IVVT SI SchoenemannD prue F Y SteigD iri tF Y DingD inghu Y MarkleD frdley F Y SchauerD endrew tFX riple wterEisotopologue reord from es hivideD entrtiX gontrols on glilEinterglil hnges in IUEy@exessA of preipittionF snX Journal of Geophysical Research: Atmospheres IIW @PHIRAD xoF IRD VURI!VUTQ SP Steen-LarsenD rF gF Y SveinbjörnsdottirD F iF Y PetersD F tF Y Masson-DelmotteD F Y GuishardD wF F Y HsiaoD qF Y JouzelD tF Y NooneD hF Y WarrenD tF uF Y WhiteD tF F gFX glimti ontrols on wter vpor deuterium exess in the mrine oundry lyer of the xorth etlnti sed on SHH dys of in situD ontinuous mesurementsF snX Atmospheric Chemistry and Physics Discussions IR @PHIRAD xoF PD PQTQ!PRHI SQ KerstelD i F Y MeijerD r e tFX yptil ssotope tio wesurements in rydrology @ghpter WAF snX AggarwalD FuF @idtFA Y GatD tF @idtFA Y FroehlichD uF @idtFAX Isotopes in the Water Cycle: past, present and future of a developing scienceF PHHSD F GröningD w Y AggarwalD F Y HellikerD fFFX elile determintion of oxygen nd hydrogen isotope rtios in tmospheri wter vpour dsored on Qe moleulr sieveF snX Rapid Communications in Mass Spectrometry PH @PHHTAD xoF PQD QTIP!QTIV TI RothmanD vFF Y GordonD sFiF Y BabikovD F Y BarbeD eF Y Chris BennerD hF Y BernathD FpF Y BirkD wF Y BizzocchiD vF Y BoudonD F Y BrownD vFF Y CampargueD eF Y ChanceD uF Y CohenD iFeF Y CoudertD vFrF Y DeviD FwF Y DrouinD fFtF Y FaytD eF Y FlaudD tFEwF Y GamacheD FF Y HarrisonD tFtF Y HartmannD tFEwF Y HillD gF Y HodgesD tFF Y JacquemartD hF Y JollyD eF Y LamourouxD tF Y Le RoyD FtF Y LiD qF Y LongD hFF Y LyulinD yFwF Y MackieD gFtF Y MassieD FF Y MikhailenkoD F Y MüllerD rFFF Y NaumenkoD yFF Y NikitinD eFF Y OrphalD tF Y PerevalovD F Y PerrinD eF Y PolovtsevaD iFF Y RichardD gF Y SmithD wFFrF Y StarikovaD iF Y SungD uF Y TashkunD F Y TennysonD tF Y ToonD qFgF Y TyuterevD lFqF Y WagnerD qFX he rsexPHIP moleulr spetrosopi dtseF snX Journal of Quantitative Spectroscopy and Radiative Transfer @PHIQA TP Chapter ssotopetF snX KerstelD i FX Handbook of Stable Isotope Analytical Tech-niquesF fdF IF ilsevierD PHHRD F USW!UVU TQ RothmanD vF F Y RinslandD gF F Y GoldmanD eF Y MassieD F F Y EdwardsD hF F Y FlaudD tF wF Y PerrinD eF Y Camy-PeyretD gF Y DanaD F Y MandinD tF F Y TrigtD vn Y DamD x Y J Reuss Y MeijerD r e tFX imultneous determintion of the PrGIrD IUyGITyD nd IVyGITy isotope undne rtios in wter y mens of lser spetrometryF snX Anal. Chem. UI @IWWWAD xoF PQD F SPWU!SQHQ TS LeeD Y SargentD X sn itu wesurement of the ter por IV yGIT y ssotope tio for etmospheri nd iologil epplitionsF snX Journal of Atmospheric & . . . @PHHSAD xoF IWWWD SSS!STT TT WenD ueEp Y SunD ioEwin Y ZhangD hiEghun Y YuD quiEui Y SargentD teve hF Y LeeD uhuiX gontinuous mesurement of wter vpor hGr nd IVyGITy isotope rtios in the tmosphereF snX Journal of Hydrology QRW @PHHVAD xoF QERD RVW!SHH TU LübkenD prnzEtosef Y DinglerD plorin Y LuckeD renrih von Y AndersD tohim Y KühnreichD fF Y SmitD rF qF tF Y EbertD FX lidtion of n exE trtiveD irorneD ompt hv spetrometer for tmospheri humidity sensing y lind interomprisonF snX Applied Physics B IIH @PHIPAD xoF PD F PRW!PTP TW GurlitD Y ZimmermannD Y GiesemannD g Y FernholzD Y EbertD Y WolfrumD AemiseggerD pF Y SturmD F Y GrafD F Y SodemannD rF Y PfahlD F Y KnohlD eF Y WernliD rFX wesuring vritions of dIVy nd dPr in tmospheri wter vpour using lser spetrosopyX n instrument hrteristion studyF snX Atmos. Meas. Tech. S @PHIPAD xoF UD IRWI!ISII UW CrossonD iFFX e vity ringEdown nlyzer for mesuring tmospheri levels of methneD ron dioxideD nd wter vporF snX Applied Physics B WP @PHHVAD xoF QD RHQ!RHV VH YeD tun Y MaD v Y HallD tvX ltrsensitive detetions in tomi nd moleulr physisX demonstrtion in moleulr overtone spetrosopyF snX JOSA B IS @IWWVAD xoF ID T!IS VI MorvilleD térôme Y RomaniniD hniele Y KerstelD irikX gvity inhned esorpE tion petrosopy with yptil peedkF ersionX PHIRF http://dx.doi.org/10.1007/ 978-3-642-40003-2_5F snX GagliardiD qF @idtFA Y LoockD rFEF @idtFAX Cavity Enhanced Spectroscopy and Sensing (Vol. 179)F pringer ferlin reidelergD PHIRF ! hys IHFIHHUGWUV!Q!TRP!RHHHQ!PSD ghpter IQD F ITQ!PHU VP MorvilleD tF Y KassiD F Y ChenevierD wF Y RomaniniD hFX pstD lowEnoiseD modeE yEmodeD vityEenhned sorption spetrosopy y diodeElser selfElokingF snX Appl. Phys. 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W @IWTUAD F UHI!UIT WR GalatryD vX imultneous e'et of hoppler nd foreign gs rodening on spetrl linesF snX Physical Review IPP @IWTIAD xoF RD F IPIV WS LeshchishinaD yF Y MikhailenkoD F Y MondelainD hF Y KassiD F Y CampargueD eFX gh of wter vpor t HFIorr etween TVVT nd URHTmEIF snX Journal of Quantitative Spectroscopy and Radiative Transfer IIQ @PHIPAD xoF IUD PISS!PITT WT CampargueD eF Y LeshchishinaD yF Y WangD vF Y MondelainD hF Y KassiD F Y NikitinD eFFX e(nements of the uwg empiril line lists @SVSPEUWIWmEIA for methne etween VHu nd PWTuF snX Journal of Quantitative Spectroscopy and Radiative Transfer IIQ McManusD t fF Y UrbanskiD Y HerndonD Y ZahniserD w FX High precision measurements of atmospheric nitrous oxide and methane using thermoelectrically cooled mid-infrared quantum cascade lasers and detectors IHI GagliardiD qF Y CastrilloD F Y IannoneD FF Y KerstelD iFFF Y GianfraniD vFX righEpreision determintion of the IQgyPGIPgyP isotope rtio using portle PFHHVE cm diodeElser spetrometerF snX Applied Physics B: Lasers and Optics UU @PHHQAD xoF ID IIW!IPR IHP KerstelD i F Y GianfraniD vX edvnes in lserEsed isotope rtio mesurementsX eleted pplitionsF snX Appl. 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B @PHHVA IHQ GiusfrediD qF Y BartaliniD F Y BorriD F Y CancioD F Y GalliD sF Y MazzottiD hF Y De NataleD FX turtedEesorption gvity ingEhown petrosopyF snX Physical Review Letters IHR @PHIHAD xoF IID IIHVHI IHR RomaniniD h Y DupréD Y JostD X xonEliner e'ets y ontinuous wve vity ringdown spetrosopy in jetEooled xy PF snX Vibrational spectroscopy IW @IWWWAD xoF PD WQ!IHT MaseykD udmiel Y LettD géline Y BironD hilippe Y RichardD trii Y BariacD hierry Y SeibtD lliX gonentrtion e'ets on lserEsed del yEIV nd del rEP mesurements nd implitions for the lirtion of vpour mesurements with liquid stndrdsF snX Rapid Communications in Mass Spectrometry PR @PHIHAD xoF PRD F QSSQ!QSTI IIP AemiseggerD pF Y PfahlD F Y SodemannD rF Y LehnerD sF Y SeneviratneD F sF Y WernliD rFX heuterium exess s proxy for ontinentl moisture reyling nd plnt trnspirtionF snX Atmospheric Chemistry and Physics IQ @PHIQAD xoF IID PWUPI!PWUVR IIQ LisD q Y WassenaarD v sF Y HendryD w tFX righEpreision lser spetrosopy hGr nd IVyGITy mesurements of miroliter nturl wter smplesF snX Analytical chemistry VH @PHHVAD xoF ID PVU!WQ IIR KuritaD xF Y NewmanD fF hF Y Araguas-AraguasD vF tF Y AggarwalD FX ivlution of ontinuous wter vpor δh nd δIVy mesurements y o'Exis integrted vity output spetrosopyF snX Atmospheric Measurement Techniques Discussions S @PHIPAD xoF PD KnohlD eX ter vpor δPr nd δIVy mesurements using o'Exis integrted vity output spetrosopyF snX AMT Q @PHHWAD F TU!UU IPI GkinisD sileios Y PoppD revor tF Y JohnsenD igfus tF Y BlunierD homsX e ontinuE ous strem )sh evportor for the lirtion of n s vity ringEdown spetrometer for the isotopi nlysis of wterF snX Isotopes in environmental and health studies RT @PHIHAD xoF RD RTQ!US IPP TremoyD quillume Y VimeuxD prnçoise Y CattaniD ylivier Y MayakiD ll Y SouleyD sde Y FavreauD quillumeX wesurements of wter vpor isotope rtios with wvelengthE snned vity ringEdown spetrosopy tehnologyX new insights nd importnt vets for deuterium exess mesurements in tropil res in omprison with isotopeErtio mss spetrometryF snX Rapid communications in mass spectrometry : RCM PS @PHIIAD xoF PQD QRTW!VH IPQ ClairD t w F Y HaniscoD pF Y WeinstockD i wF Y MoyerD i tF Y SayresD h F Y KeutschD p xF Y KrollD t rF Y DemuszD t xF Y AllenD x F Y SmithD t fF Y J. R. Spackman Y AndersonD t qF Y St ClairD t wF Y SpackmanD t FX e new photolysis lserEindued )uoresene instrument for the detetion of rPy nd rhy in the lower strtosphereF snX The Review of scientic instruments UW @PHHVAD xoF TD HTRIHI IPR IannoneD osrio F Y RomaniniD hniele Y CattaniD ylivier Y MeijerD rrro F tF Y KerstelD irik F FX ter isotope rtio @ δ P r nd δ IV yA mesurements in tmoE spheri moisture using n optil feedk vity enhned sorption lser spetrometerF snX Journal of Geophysical Research IIS @PHIHAD xoF hIHD hIHIII IPS JohnsonD v F Y SharpD hF Y GalewskyD t Y StrongD w Y Van PeltD hF Y DongD p Y NooneD hX rydrogen isotope orretion for lser instrument mesurement is t low wE ter vpor onentrtion using onventionl isotope nlysesX pplition to mesurements from wun vo yservtoryD rwiiF snX Rapid communications in mass spectrometry : RCM PS @PHIIAD xoF SD THV!IT IPT WenD ueEp Y LeeD uhui Y SunD ioEwin Y WangD tinEvin Y TangD Euun Y LiD hengEqong Y YuD quiEui Y HavenD xewX snteromprison of pour gommeril enE lyzers for ter por ssotope wesurementF snX Journal of Atmospheric and Oceanic Technology PW @PHIPAD xoF PD PQS!PRU IPU EllehojD w hF Y Steen-LarsenD r gF Y JohnsenD tF Y MadsenD w fFX seEvpor equilirium frtiontion ftor of hydrogen nd oxygen isotopesX experimentl investigE tions nd implitions for stle wter isotope studiesF snX Rapid communications in mass spectrometry : RCM PU @PHIQAD xoF IWD PIRW!SV IPV PicarroX High-Precision VaporizerF http://www.picarro.com/products_solutions/ peripherals/high_precision_vaporizerF ersionX PHIR IPW GkinisD sileios Y MorrieD lerie Y JonesD yler Y VaughnD frue Y WhiteD tmesX righ resolution D high preision D simultneous mesurements of δh nd δIV y using gh nlyzer with n ultrsoni neulizer smple preprtion module F IS @PHIQA IQH LeeD iri FX Microdrop GenerationF fo tonD pv X gg ressD PHHQF ! PUP F ! IQU RothmanD vFF Y JacquemartD hF Y BarbeD eF Y Chris BennerD hF Y BirkD wF Y BrownD vFF Y CarleerD wFF Y ChackerianD gF Y ChanceD uF Y CoudertD vFrF Y DanaD F Y DeviD FwF Y FlaudD tFEwF Y GamacheD FF Y GoldmanD eF Y HartmannD tFEwF Y JucksD uFF Y MakiD eFqF Y MandinD tFEF Y MassieD FF Y OrphalD tF Y PerrinD eF Y RinslandD gFF Y SmithD wFeFrF Y TennysonD tF Y TolchenovD FxF Y TothD FeF

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	IQI @PHHSAD xoF THVD ISQW!ISTS PR McNaughtD eF hF Y WilkinsonD eFX Compendium of Chemical Terminology, 2nd ed. "The Gold Book"F PndF yxford X flkwell ienti( ulitionsD IWWU PS MookD illem qFX Lecture Notes on Stable Isotope HydrologyF snterntioF PHHIF ! SU ! TH F PT International Atomic Energy AgencyX eferene heet for snterntionl wesureE ment tndrds G seieF PHHW @wyAF ! ienti( reportF ! S F Radiocarbon QP @IWWHAD xoF QD F QTW!QUR QP CrissD F iFX Principles of Stable Isotope DistributionF yxford niversity ressD eD IWWW QQ ChackoD F Y ColeD hF Y HoritaD tFX iquilirium oxygenD hydrogen nd ron isoE tope frtiontion ftors pplile to geologi systemsF snX Reviews in Mineralogy and Geochemistry RQ @PHHIAD F I!VI QR MerlivatD v Y NiefD qX prtionnement isotopique lors des hngements d9étt solideE vpeur et liquideEvpeur de l9eu à des tempértures inférieures à H°gF snX Tellus IW @IWTUAD xoF ID IPP!IPU QS MajoubeD wFX prtionnement en IVy entre l gle et l vpeur d9euF snX J. Chim. Phys. 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Chem.1 UI @IWWWAD F PPSH!PPSQ SU BegleyD sFF Y ScrimgeourD gFwFX righEpreision dPr nd dIVy mesurement for wter nd voltile orgni ompounds y ontinuousE)ow pyrolysis isotope rtio mss spetrometryF snX Anal. Chem. TW @IWWUAD F ISQH!ISQS SV PhillipsD eF Y FourelD pF Y MorrisonD tFX yxygenEdeuterium isotopi mesurements using vriety of pyrolysis methods â¿ sw ontinuousE)ow tehniquesF snX Isotopes in Environ. Health Stud. QT @PHHHAD F QRU und Spektrometer sowie die Anwendung für die AtmosphärenforschungD urlsruhe snstiE tute of ehnology G niversity of reidelergD hissFD PHIQ WW RomaniniD hF Y ChenevierD wF Y KassiD F Y SchmidtD wF Y ValantD gF Y RamonetD wF Y LopezD tF Y JostD rFEtFX yptilEfeedk vityEenhned sorptionX ompt strtegies for isotope rtio infrred spetrosopy for tmospheri IQgyPGIPgyP mesureE mentF snX Atmospheric Measurement Techniques Discussions T @PHIQAD xoF ID UWS!VPQ tio petrometerF tournl of etmospheri nd yeni ehnologyF snX J Atmos Ocean Technol PT @PHHWAD xoF UD IPUS!IPVV for GasesF http://www.bronkhorst.com/files/downloads/datasheets/el-flow/ f-201cv.pdfF ersionX PHIR SW WPW!QP TH HanD vEp Y SchroederD tF Y McCannD eF Y GamacheD F F Y WattsonD F fF Y YoshinoD uF Y ChanceD uF F Y JucksD uF F Y BrownD vF F Y NemtchinovD F Y VaranasiD FX ri rsex wyvigve igygysg heefei exh reu @rsE ex ewyrisg yuesyxAX IWWT ihssyx @eprint from t unt peE tros dit rnsferD vol THD pg TTSEUIHD IWWVAF snX JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER III @PHIHAD xoF IID ISTV!ITIQ TR KerstelD i F Y t Y PlattD Y BurrowsD tX vightweight diode lser spetrometer grsvh @gompt righEltitude snEsitu vser hiodeA for lloonorne mesurements of wter vpor nd methneF snX APPLIED OPTICS RR @PHHSAD xoF ID WI!IHP UH HuangD rifeng Y LehmannD uevin uFX ensitivity limits of ontinuous wve vity ringEdown spetrosopyF snX The journal of physical chemistry. A IIU @PHIQAD xoF SHD IQQWW!RII UI RomaniniD h Y VentrillardD s Y MéjeanD q Y MorvilleD t Y KerstelD iX sntrodution to vity enhned sorption spetrosopy I sntrodutionF ersionX PHIRF http://dx. doi.org/10.1007/978-3-642-40003-2_1F snX GagliardiD qF @idtFA Y LoockD rFEF @idtFAX Cavity-Enhanced Spectroscopy and Sensing (Vol. 179)F pringer ferlin reidelergD PHIRF ! hys IHFIHHUGWUV!Q!TRP!RHHHQ!PID F I!SI UP Paldus B. A. Y Zare R. N.X esorption petrosopiesX prom irly feginE nings to gvityEingdown petrosopyF ersionX IWWWF http://dx.doi.org/10.1021/ bk-1999-0720F snX BuschD uenneth F @idtFA Y BuschD wrinn eF @idtFAX Cavity-Ringdown Spectroscopy fdF UPHF shingtonD hg X emerin ghemil oietyD IWWWF ! hys IHFIHPIGk!IWWW!HUPHF ! sfx H!VRIP!QTHH!QD RW!UH UQ ZeeD oger hF Y HodgesD toseph F Y LooneyD tF FX ulsedD ingleEwode gvity ingdown petrosopyF snX Applied Optics QV @IWWWAD xoF IVD QWSI UR DemtröderD olfgngX Laser Spectroscopy: Vol. 1: Basic PrinciplesF fdF WF pringerE erlgD PHHUF ! sfx QSRHUQRIV US PaulD t fF Y LapsonD v Y AndersonD t qFX ltrsensitive sorption spetrosopy with highE(nesse optil vity nd o'Exis lignmentF snX Applied optics RH @PHHIAD xoF PUD RWHR!IH UT WEBSTERD g Y MAYD h Y TRIMBLED ge Y CHAVED q Y KENDALLD tX esgep @iEPA vei sxpeihEefysyx igywii @evseA py sxEs eyrisg wieiwix yp rgvD xPyD grRD xyPD exh rxyQF snX APPLIED OPTICS QQ @IWWRAD xoF QD RSR!RUP Rapid Communications in Mass Spectrometry PQ @PHHWAD F IVUW!IVVR VU HabigD tn gFX Bestimmung von Wasserdampfpartialdrücken und Wasserisotopenverhält-nissen mittels resonatorverstärkter Absorptionsspektroskopie -Entwicklung von Software WV WerleD X eury nd preision of lser spetrometers for tre gs sensing in the presene of optil fringes nd tmospheri turuleneF snX Applied Physics B -Lasers and Optics IHP @PHIHAD F QIQ!QPW mesurements of delt gEIQ nd delt yEIV in ron dioxide with ryogenEfree gveF snX APPLIED PHYSICS B-LASERS AND OPTICS WP @PHHVAD xoF QD F RSI!RSV IIH WenD FEpF Y MengD F Y ZhangD FEF Y SunD FEwF Y LeeD FX ivluting lirtion mentsD ijksuniversiteit qroningenD hissFD PHHW IIW IannoneD osrio F Y RomaniniD hniele Y KassiD mir Y MeijerD rrro F tF Y Ker-stelD irik F FX e wirodrop qenertor for the glirtion of ter por ssotope spetrosopi dtseF snX Journal of Quantitative Spectroscopy and Radiative Transfer WT @PHHSAD xoF PD IQW!PHR IQV Bronkhorst High-Tech B.V.X Datasheet F-201CV, Mass Flow Controller UU SturmD g Y maniniD hniele Y MeijerD rrro e tF Y DhaniyalaD uresh Y SnelsD wrel Y KerstelD irik FX hevelopment nd irorne opertion of ompt wter isotope rtio infrred spetrometerF snX Isotopes Environ Health Stud. RS @PHHWAD xoF RD QHQ!PH VR LandsbergD t Y RomaniniD h Y KerstelD iX ery high (nesse optilEfeedk vityE enhned sorption spetrometer for low onentrtion wter vpor isotope nlysesF snX Optics letters QW @PHIRAD xoF UD IUWS!V VS JamesD pF Y RoosD wFX winuit E system for funtion minimiztion nd nlysis of the prmeter errors nd orreltionsF snX Computer Physics Communications IH @IWUSAD xoF TD QRQ!QTU spetrosopy versus highEtemperture onversion isotope rtio mss spetrometry nd se study on PS àPr nd àIVy of pure wter smples nd loholGwter mixturesF snX Y NelsonD h hF Y McManusD t fF Y EmmeneggerD vX righ preision nd ontinuous (eld Absorption Spectrometer (OF-CEAS) for atmospheric water vapor isotope ratio measure-Y Vander AuweraD tF Y VaranasiD F Y WagnerD qFX he rsex PHHR moleulr P IHW TuzsonD f Y MohnD t Y ZeemanD w tF Y WernerD eF Y EugsterD Y ZahniserD w F IIV IannoneD osrio FX Development of a near-infrared Optical Feedback Cavity Enhanced WU AllanD hFFX essg yp eywsg piixg exhehF SR @IWTTAD xoF VT BrandD eF Y GeilmannD r Y CrossonD i F Y Y RellaD g FX gvity ringEdown VV DemtröderD olfgngX UF imission und esorption elektromgnetisher trhlung durh etomeF snX Exerimentalphysik 3 -Atome, Moleküle und FestkörperF PHHSD F PQI!PQV VW TittelD prnk uF Y RichterD hirk Y FriedD elnX widEsnfrred vser epplitions in petrosopyF ersionX PHHQF http://dx.doi.org/10.1007/3-540-36491-9F snX SorokinaD srin F @idtFA Y VodopyanovD uonstntin vF @idtFAX Solid-State Mid-Infrared Laser Sources fdF VWF ferlinD reidelerg X pringer ferlin reidelergD PHHQF ! hys IHFIHHUGQ!SRH!QTRWI!WF ! sfx WUV!Q!SRH!HHTPI!QD RSV!SPW WH LepèreD wurielX vine pro(le study with tunle diode lser spetrometersF snX Spec-trochimica acta. Part A, Molecular and biomolecular spectroscopy TH @PHHRAD xoF IRD QPRW! SV IHT MorettiD v Y SassoD e Y GianfraniD v Y CiuryloD X gollisionlEfrodened nd hikeE xrrowed vineshpes of rPITy nd rPIVy rnsitions t IFQW umF snX Journal of molecular spectroscopy PHS @PHHIAD xoF ID PH!PU IHU WilliamsD hvid FX NASA -Earth Fact SheetF http://nssdc.gsfc.nasa.gov/ planetary/factsheet/earthfact.htmlF ersionX PHIQ IHV R.D qon(ntiniX he deltEnottion nd the mssEspetrometri mesurement tehniquesF snX R.D qt tF @idtFA Y GonfiantiniD F @idtFAX Stable Isotope Hydrology, Deuterium and Oxygen-18 in the Water CycleF ehnilF ienn X seieD IWVID ghpter RD F QS!VR IIT WangD vixin Y CaylorD uelly uF Y DragoniD hniloX yn the lirtion of ontinuousD highEpreision dIVy nd dPr mesurements using n o'Exis integrted vity output spetrometerF snX Rapid Communications in Mass Spectrometry PQ @PHHWAD xoF RD F SQH!SQT IIU GuptaD riy Y NooneD hvid Y GalewskyD toseph Y SweeneyD golm Y VaughnD frue rFX hemonstrtion of highEpreision ontinuous mesurements of wter vpor isoE topologues in lortory nd remote (eld deployments using wvelengthEsnned vity ringEdown spetrosopy @ Egh A tehnologyF snX . . . in mass spectrometry @PHHWAD PSQR!PSRP systems to elevted temperturesF snX PalmerD hF eF @idtFA Y Fernández-PriniD F @idtFA Y HarveyD eF rF @idtFAX Aqueous systems at elevated temperatures and pressures: Physical chemistry in water, steam and hydrothermal solutionsF ilsevierD PHHRD F PUU!QIW IQT Harvard ApparatusX ser9s wnul E ump II io lus iliteF PHIPF ! ienti( reportF ! V F WI HuangD inglei Y @PHIPAD xoF ISD IVSS!IVUQ spetrometer for relEtime mesurement of tmospheri methneF snX Appl. Phys. B VQ @PHHTAD xoF RD TSW!TTU HyperPhysicsF http://hyperphysics.phy-astr.gsu.edu/hbase/ kinetic/menfre.htmlF ersionX PHHI IIS FranzD eter Y RöckmannD homsX e new ontinuous )ow isotope rtio mss spetromE etry system for the nlysis of deltPrD deltIUy nd deltIVy of smll @IPH mirogA wter smples in tmospheri pplitionsF snX Rapid communications in mass spectrometry : IQS HoritaD tF Y ColeD hF FX tle isotope prtitioning in queous nd hydrotherml RCM IV @PHHRAD xoF IQD IRPW!QS IQR BirdD Ffyron Y StewartD rren iF Y LightfootD idwin xFX Transport Phenomena (Second Edition)F tohn iley 8 sonsD PHHP IHH NelsonD h hF Y IHS NaveD grl FX IQI IannoneD F Y RomaniniD hF Y MeijerD rF Y KerstelD iFX glirtion of diode lser wter isotope rtio spetrometer for inEsitu mesurements in the troposphere nd lower strtosphere X sing piezoEinjetor to produe wter with know onentrtion nd isotopi signture in the lortoryF snX Geophysical Research Abstracts (Vol. 9, p. 02398)D PHHU IQP GansD ferendEtn de Y SchubertD lrih FX snkjet printing of wellEde(ned polymer dots nd rrysF snX Langmuir : the ACS journal of surfaces and colloids PH @PHHRAD xoF IVD UUVW!WQ IQQ MeinhartD gFhF Y ZhangD rFX he )ow struture inside mirofrited inkjet printE hedF snX Journal of Microelectromechanical Systems W @PHHHAD xoF ID TU!US III SchmidtD wrkus Y PVPI!PVSS IQW Harvard ApparatusX Harvard Apparatus -Pico Plus EliteF http://www. harvardapparatus.com/webapp/wcs/stores/servlet/product_11051_10001_64201_ -1_HAI_ProductDetail___#specificationstabF ersionX PHIR IPH SturmD Y sfx H!VRWQ!ISSW! 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HellikerD frent F Y RodenD tohn F Y CookD grig Y EhleringerD tmes FX e rpid nd preise method for smpling nd determining the oxygen isotope rtio of tmospheri wter vporF snX Rapid communications in mass spectrometry : RCM IT @PHHPAD xoF IHD RiedelD olfgng tF Y WolfD relmutX weiesX oketforne unle hiode vser esorption petrometerF snX Applied Optics QV @IWWWAD xoF PSD SQQV ISP fsfvsyqer TV BuchholzD fF Y ZhangD Y NooneD hX en introdution to stle wter isotopes in limte modelsX ene(ts of forwrd proxy modelling for pleolimtologyF snX Climate of the Past T @PHIHAD xoF ID IIS!IPW fsfvsyqer ISQ UV

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Acknowledgments

QA he surfe lyer of the droplet with volume V S (t) nd isotope rtio R S (t)D whih is in)uened y the evportion from the surfe lyer nd ontinuous supply of the isotope stndrd from the ore volume V C F por the surfe volumeD we ssume onstnt thikness dD whih is determined y the di'usion of wter moleules in the surfe lyerF por smll dD we n pproximte V C to e the surfe re A S multiplied with the thikness of the lyerX

pigure fFIX sllustrtion of the dimensions of droplet formed during wter injetion with xsgF @A he syringe needle hs dimeter of 2r 0 nd the height of the droplet is h(t)F @A untities used to ompute the volume of the droplet over time elterntivelyD we n lso express V C (t) s the di'erene etween the totl droplet volume

sn volume V with onstnt densityD the isotope rtio n e lulted s

with V inditing the volume of the most undnt nd V the volume of rre isotopeF por V D this leds to

he rre isotope in the surfe lyer n thus e desried y the following reltionX

whih leds together with eqution @fFIIA toX

husD we (nlly get

ith eqF fFID fFVEfFIHD we n now lulte the isotope rtio in the surfe lyer nd the evported wterF he isotope rtio of the enrihed surfe lyer n e lulted y R S (t) = ψ(t) 1 + ψ(t) @fFPUA nd the isotope rtio of the vpor phse with R e (t) = R S (t) • α V @fFPVA