Alexandra Samier Foubert
email: alexandra.samier-foubert@u-bordeaux.fr

Anne Pavy-Le Traon

Tiphaine Saulnier

Melanie Le Goff

Margherita Fabbri

Catherine Helmer

Olivier Rascol

Cecile Proust-Lima

Wassilios G Meissner

Dr Alexandra Foubert-Samier

Mélanie Le- Goff

Cécile Proust-Lima

An Item Response Theory analysis of the Unified Multiple System Atrophy Rating Scale

Keywords: Multiple system atrophy, Unified Multiple System Atrophy Rating Scale, evaluation

de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction

Multiple system atrophy (MSA) is a rare progressive neurodegenerative synucleinopathy characterised by various combinations of autonomic failure, parkinsonism and cerebellar ataxia. Depending on the predominance of the symptoms, two forms are distinguished, i.e. MSA-P with predominant parkinsonism and MSA-C with predominant cerebellar impairment.

The prognosis is poor with a median survival between 6 and 10 years [START_REF] Meissner | Multiple System Atrophy: Recent Developments and Future Perspectives[END_REF][START_REF] Foubert-Samier | Disease progression and prognostic factors in multiple system atrophy: A prospective cohort study[END_REF].

The Unified Multiple System Atrophy Rating Scale (UMSARS) was developed in 2004 for the quantitative assessment of disease severity in MSA patients [START_REF] Wenning | Multiple System Atrophy Study Group, Development and validation of the Unified Multiple System Atrophy Rating Scale (UMSARS)[END_REF]. The scale is composed of four sub-scales: UMSARS I is a functional score based on 12 questions that evaluate activities of daily living. Each question is scored from 0 to 4, with a higher score indicating a lower functional status; UMSARS II is a motor examination comprising 14 questions also scored from 0 to 4; UMSARS III consists of the measurement of supine and standing blood pressure; UMSARS IV is a disability scale which ranges from 1 (no disability) to 5 (severe disability). UMSARS I and II were used to describe disease progression in natural history studies in MSA and as primary endpoints in treatment trials [START_REF] Meissner | Multiple System Atrophy: Recent Developments and Future Perspectives[END_REF].

Despite the use of this scale in MSA for almost 20 years, some essential aspects are still unknown such as the contribution of the different items to the total score and their progression during different disease stages [START_REF] Palma | Limitations of the Unified Multiple System Atrophy Rating Scale as outcome measure for clinical trials and a roadmap for improvement[END_REF]. Hence, the main objective of this study was to identify UMSARS I and II subscale items that best describe MSA progression over time. We also estimated the minimum sample size required for treatment trials according to these items.

Methods

Study design and population

Data of 557 MSA patients who were enrolled at the Bordeaux and Toulouse sites of the French MSA Reference Centre between 2008 and December 2019 were analyzed. Diagnostic procedures and annual follow-up assessments (including UMSARS) of the cohort were described in detail elsewhere [START_REF] Foubert-Samier | Disease progression and prognostic factors in multiple system atrophy: A prospective cohort study[END_REF]. All patients met current consensus criteria for a diagnosis of probable or possible MSA and were examined by a movement disorder specialist [START_REF] Gilman | Second consensus statement on the diagnosis of multiple system atrophy[END_REF]. All patients provided written informed consent and the cohort is registered with the CNIL (Commission Nationale Informatique et Liberté).

Statistical analyses

To identify which items of UMSARS I and II subscales best describe MSA progression, we analyzed the repeated measures of the 26 items using an Item Response Theory (IRT) model extended to handle repeated measures over time [START_REF] Proust-Lima | Analysis of multivariate mixed longitudinal data: a flexible latent process approach[END_REF][START_REF] Baker | Item Response Theory: Parameter Estimation Techniques[END_REF]. IRT models assume that all items measure the same continuum, the severity of the disease, and assess the location and discrimination ability of each item along this continuum. The extension to a longitudinal setting further analyzes the trajectory of the underlying disease severity according to time since the first visit in a linear mixed model. To better translate the severity continuum in a concrete disease course scale, we defined five stages of disease progression according to the UMSARS IV disability subscale (stage 1: completely independent, essentially normal; stage 2: not completely independent, needs help with some chores; stage 3: more dependent, help with half of chores; stage 4: very dependent, does a few chores alone or begins alone; and stage 5: totally dependent and helpless) and assessed the information carried by each item represented by a percentage of information each stage (using the Fisher information) [START_REF] Magis | A Note on the Equivalence Between Observed and Expected Information Functions With Polytomous IRT Models[END_REF]. The most informative items were determined as those providing the highest information percentage at most UMSARS IV stages.

We completed the analysis by estimating the minimum sample size required for treatment trials according to UMSARS I and II total scores or subscores derived from selected items by using Monte Carlo simulations and by assuming a linear mixed model for the statistical analysis of change. We fixed the power of detection for a difference between two treatment groups at 80% and the effect size at 30%. We considered UMSARS data every 6 months and accounted for the high risk of death by generating a dropout of 5% at each visit.

We performed the calculation of the sample size estimates on the entire cohort and on an early disease subpopulation of our cohort relevant for disease-modification trials in MSA, i.e. disease duration since symptom onset less than 3 years and UMSARS IV score ≤ 3.

Results

Demographics

A total of 557 MSA patients were included with a mean follow-up of 2.3 years (maximum of 10.5 years); 418 (75.0%) met consensus criteria for probable MSA and 378 (67.9%) had MSA with predominant parkinsonism (MSA-P) (Table e-1). The study population included 270 (48.5%) male patients. Mean age at the first visit was 64.5 ± 8.3 years and mean disease duration since symptom onset was 4.7 ± 2.7 years. A total of 1545 UMSARS I and II assessments (mean 2.8 per subject) and 1533 UMSARS IV assessments (mean 2.7 per subject) were available for the analysis. Among the 557 MSA patients, 266 (47.8%) died during follow-up.

Progression of UMSARS I and II items over time

The majority of items progressed substantially with disease duration (Figure 1a and1b), with the exception of items I.9 (orthostatic symptoms), I.10 (urinary dysfunction), II.3 (ocular motor dysfunction) and II.4 (tremor at rest) which showed only slight to moderate impairments during follow-up, as well as item I.11 (sexual function), which showed almost maximum impairment at the first visit. Among the progressing items, the first reached maximum impairment after 6 years (e.g., II.11 (arising from chair)).

Progression of UMSARS I and II items at different disease stages

Worsening was progressive across UMSARS IV stages 1 to 4 (Figure 2) for the majority of items. In other words, worsening of the majority of UMSARS I and II items was linked to the increasing disability from UMSARS IV stages 1 to 4. Stage 5 was reached by only 51 patients (9.1% of the cohort), because the majority died before reaching this stage or were unable to come to the hospital for the annual assessment because of disease severity. By UMSARS IV stage 4, 17 items had reached the maximum score of 4. Some items did not follow this progression with disability stages, such as item I.11 (sexual function) which reached maximum scores before UMSARS IV stage 2, or items I.9 (orthostatic symptoms) and II.4 (tremor at rest) which reached moderate to severe levels only at UMSARS IV stage 5.

Most informative items across disease course stages

The information carried by each item at each of the five UMSARS IV stages differed substantially (Figure e-1, and Table e-2 for the stage-specific ranking of the items).

The most informative items at UMSARS IV stage 5 were very different from those at UMSARS IV stages 1 to 4, with the exception of item I.1 (speech) which explained roughly 5% of the information at all stages. Across the first four UMSARS IV stages, seven items consistently appeared among the 10 most informative: I.1 (speech), I.4 (cutting food and handling utensils, stage-specific Information percentage range (I-range)=5.4-9.0%), I.5 (dressing, I-range=7-9.1%), I.6 (hygiene, I-range=6.4-9.3%), I.7 (walking, I-range=6.7-8.7%), II.14 (gait, I-range=7.5-8.6%) and II.9 (leg agility, I-range=4.4-6%). Four additional items brought substantial information, especially at UMSARS IV stages 1-4: II.2 (speech, I-range=4.8-6.4%), II.8 (finger tapping, I-range=3.6-6.0%), II.13 (body sway, I-range=4.3-5.2%) and II.11 (arising from chair, I-range=2.7-9.1%). In total, these 11 items carried 64.8%, 74.3%, 74.6%, 71.3% and 30.1% of information at UMSARS IV stages 1, 2, 3, 4 and 5, respectively.

Sample size estimates

To detect an effect size of 30% with a power of 80% in a linear mixed model at one year for a parallel group trial, the necessary sample size by randomisation arm would be 157 subjects when using the UMSARS I + II score, and 162 subjects with the 11 selected items. For the early disease population (n=227) that is relevant for disease-modification trials in MSA, the necessary sample size would be 100 subjects based on the UMSARS I + II score and 110 subjects with the 11 selected items using the linear mixed model.

Discussion

Based on our cohort of 577 patients with long-term follow-up, we showed that the majority of UMSARS I and II items substantially progressed with disease duration and disability, in both early and advanced stages. We identified 11 items which best described the progression in terms of disability, with a roughly equivalent minimum sample size required for clinical trials.

Most of these 11 items correspond to activities of daily living (ADL) such as walking/gait, speech, dressing, hygiene, and cutting food. Our results are in agreement with a recent study on the limitations of UMSARS based on a smaller sample of 70 MSA patients [START_REF] Palma | Limitations of the Unified Multiple System Atrophy Rating Scale as outcome measure for clinical trials and a roadmap for improvement[END_REF]. In line with the latter [START_REF] Palma | Limitations of the Unified Multiple System Atrophy Rating Scale as outcome measure for clinical trials and a roadmap for improvement[END_REF], we further observed that UMSARS I and II do not well capture changes in symptoms related to autonomic dysfunction such as orthostatic hypotension or sexual function, as was also reported for orthostatic symptoms during scale development [START_REF] Wenning | Multiple System Atrophy Study Group, Development and validation of the Unified Multiple System Atrophy Rating Scale (UMSARS)[END_REF][START_REF] Palma | Limitations of the Unified Multiple System Atrophy Rating Scale as outcome measure for clinical trials and a roadmap for improvement[END_REF]. This could either be because of an inaccurate construct of these items or because autonomic symptoms are the consequence of interrelated mechanisms including the severity of OH, its treatment and the severity of motor disability. Indeed, the level of supine blood pressure unlikely explains the lack of progression of orthostatic symptoms since we observed only a weak correlation for the first two years of follow-up (Table e-3). In addition, we found a moderate correlation between orthostatic symptoms and the drop in diastolic/systolic blood pressure during the first three years of follow-up (Table e-3 andTable e-4), and a weak correlation with body sway and gait items at baseline, one and three years of follow-up (Table e-5). This finding may also suggest a sort of ceiling effect for the impact of OH; once the patient reaches the later disease stage, being frequently wheelchair bound, OH may lose part of its functional impact. At the same time, the severity of orthostatic hypotension did not progress significantly over time, independently of the presence of anti-hypotensive treatment (Table e-4), in line with our previous observation [START_REF] Foubert-Samier | Disease progression and prognostic factors in multiple system atrophy: A prospective cohort study[END_REF]. Taken together, these observations suggest that the item referring to orthostatic symptoms is complex and depends on several factors including the severity of orthostatic hypotension but also motor disability.

Similarly, the progression of urinary dysfunction was not well captured by the UMSARS I subscale. The item used to evaluate urinary dysfunction refers to drug treatment or catherization and merges incontinence and retention. The most severe score for this item refers to the presence of an indwelling catheter which could be due to the patient's motor disability or the severity of urinary dysfunction itself. It is well known that retention, as reflected by increasing post-void residual volume, progresses with motor disability and that detrusor hypocontractility is associated with the risk of death through infections [START_REF] Xing | Neurogenic lower urinary tract dysfunction predicts prognosis in patients with multiple system atrophy[END_REF][START_REF] Ito | Incomplete emptying and urinary retention in multiple-system atrophy: When does it occur and how do we manage it?[END_REF][START_REF] Yamamoto | The severity of motor dysfunctions and urinary dysfunction is not correlated in multiple system atrophy[END_REF]. An item evaluating urine retention would be useful to follow urinary dysfunction and related patient disability. The lack of an accurate evaluation of these dysautonomic features by the UMSARS may explain why the impact of autonomic dysfunction on disease progression or survival was not consistent across different studies [START_REF] Foubert-Samier | Disease progression and prognostic factors in multiple system atrophy: A prospective cohort study[END_REF][START_REF] Low | Natural history of multiple system atrophy in the USA: a prospective cohort study[END_REF][START_REF] Watanabe | Progression and prognosis in multiple system atrophy: an analysis of 230 Japanese patients[END_REF][START_REF] Wenning | European Multiple System Atrophy Study Group, The natural history of multiple system atrophy: a prospective European cohort study[END_REF].

The UMSARS has been used as primary endpoint in all but one recent randomized, controlled treatment trials [START_REF] Meissner | Multiple System Atrophy: Recent Developments and Future Perspectives[END_REF]. Here, we have identified 11 items which carried the most relevant information for each of the five UMSARS IV disability stages. Most of them represent ADL such as walking/gait, speech, dressing, hygiene, and cutting food, which are also reflected in the items assessing movement (arising from chair, leg agility and finger tapping). Some of these items (hygiene, walking, speech, leg agility, arising from chair, gait) were also identified in the recent study [START_REF] Palma | Limitations of the Unified Multiple System Atrophy Rating Scale as outcome measure for clinical trials and a roadmap for improvement[END_REF]. We note a few differences, for example for handwriting, which could be due to our longer follow-up (one year in the recent study vs. up to 10 years in our). Using the 11 identified items for an abbreviated UMSARS would allow to more directly capture a treatment effect on patient-centered symptoms, with an equivalent sample size compared to the UMSARS I + II score. In this line, the use of a primary endpoints reflecting the patient perspective is an increasing request by regulatory authorities such as the Food and Drug Administration. Having said this, a validation study incorporating these 11 items or the seven directly reflecting relevant activities of daily living plus additional patientcentered outcomes into a scale will nevertheless be necessary.

In conclusion, our study provides novel insights into the construct of the UMSARS, its sensitivity to change and future directions for its improvement. These will be essential for the recently established MDS UMSARS Revision Task Force which aims to develop a scale for the assessment (i) of the full spectrum of symptoms and their severity (e.g. for natural history studies) and (ii) of critical patient-centred outcomes in an abbreviated version that may serve as primary outcome for intervention trials and that satisfies the expectations of regulatory authorities. Black lines represent the transition to a higher level of UMSARS IV.

Figure 1 :

 1 Figure 1: Evolution of each UMSARS I and II item score since the first visit (n=557 MSA

Figure 2 :

 2 Figure 2: Evolution of each UMSARS I and II item during the different disease stages (n=557).

Financial disclosures

AFS reports personal fees from LVL medical, outside the submitted work. APLT reports personal fees from Biohaven. TS, CH, CPL, MF, MLG have nothing to declare. OR has acted as a scientific advisor for drug companies developing antiparkinsonian medications (Abbott, Abbvie, Acorda, Adamas, BIAL, Biogen, Boehringer-Ingelheim, Cynapsus, GSK, Impax, Merck, Osmotica, Oxford-Biomedica, Lundbeck, Novartis, Prexton, Servier, Sunovion, TEVA, UCB, Zambon). WGM reports fees for editorial activities with Elsevier, consultancy fees from Lundbeck, Biohaven, Roche, Alterity, Servier and Inhibikase, and teaching honoraria from UCB.

Financial disclosure related to research

The authors stated no financial disclosure.


Elise Sales

Naïl Mulatier

Louise Wittmann

Antoine Fernandes

B Éatrice Vacher

Jose Penuelas

Effect of dry heat treatment between room temperature and 160 °C on surgical mask

Keywords: Covid-19, Pandemic, Face Masks, Decontamination, Dry Heat

The Covid-19 crisis has led to a high demand and use of surgical masks worldwide, causing risks of shortages and pollution. Therefore, decontamination of surgical masks could be an opportunity to reduce these risks.

In our study, we applied dry heat to the masks for 15 minutes at different temperatures and studied the consequences of heat on surface chemistry and fiber morphology. We focus here on the effects of dry heat treatment on the masks and not on the verification of mask disinfection, which has been thoroughly studied in existing literature.

The masks that were heated to 70°C, 100°C, 130°C, 140°C, 150°C did not show significant changes at the nanometric scale and the standard deviation of the surface temperature of the worn masks is similar to that of the unheated control mask. However we show a slight heating altered the hydrophobicity of the surface, and induced a significative modification of the wetting angle of water droplets. The mask heated to 157°C has a higher surface temperature standard deviation and fused fibers are observed by scanning electron microscopy. The mask heated to 160°C melted and then hardened as it cooled making it completely unusable.

Introduction

The significant impact of the Covid-19 outbreak paralyzed many countries in the world, forcing them to lockdown the population in order to stop the spread of the epidemic. The use of surgical masks helped to slow down the epidemic [START_REF] O'dowd | Face Masks and Respirators in the Fight Against the COVID-19 Pandemic: A Review of Current Materials[END_REF] [START_REF] Cheng | Face Masks Effectively Limit the Probability of SARS-CoV-2 Transmission[END_REF]. In february 2020, single-use face mask production in China increased to 116 million per day [START_REF] Aragaw | Surgical Face Masks as a Potential Source for Microplastic Pollution in the COVID-19 Scenario[END_REF].

Three major types of masks can be used : "Type I" masks, "Type II" and "Type IIR" masks. Type I masks filter 95% of the bacteria from an aerosol of average size 3 µm ; type II masks filter 98% of the bacteria from an aerosol of average size 3 µm ; type IIR filter the same as type II masks but are also splash resistant [START_REF] Quesnel | The Efficiency of Surgical Masks of Varying Design and Composition[END_REF] [START_REF]An Overview of Filtration Efficiency through the Masks: Mechanisms of the Aerosols Penetration[END_REF]. A surgical mask can be either type. Type IIR masks are dedicated to the medical personnel.

Surgical masks are composed of non-woven polypropylene ; they have three layers and three folders. The first and the third layer are the same and the second one is a filter. The filter is made of meltblown [START_REF] Zuo | Nanofibers from Melt Blown Fiber-in-Fiber Polymer Blends[END_REF] [6] [START_REF] Chua | Face Masks in the New COVID-19 Normal: Materials, Testing, and Perspectives[END_REF] and is charged during the fabrication in order to increase the filtration capacity. Both the first and the third layer are made of 30 µm diameter fibers, the second one is made of 5 µm diameter fibers [START_REF] Peeples | Face Masks: What the Data Say[END_REF]. The daily use of the masks triggered a massive micro-plastic pollution [START_REF] Aragaw | Surgical Face Masks as a Potential Source for Microplastic Pollution in the COVID-19 Scenario[END_REF]. According to the Oceanasia association, 1.56 billion face masks entered the oceans in 2020. Once in the oceans, these masks disintegrate into micro-particles which significantly disrupt the local ecosystem [START_REF] Dybas | Surgical masks on the beach: COVID-19 and marine plastic pollution[END_REF]. Thus, the reuse of surgical masks has been envisioned by many scientists. Various techniques have been tested: UV treatment [10] [11] [12] [13] [START_REF] Côrtes | Decontamination and Re-Use of Surgical Masks and Respirators during the COVID-19 Pandemic[END_REF], steam [START_REF] Li | It's Not the Heat, It's the Humidity: Effectiveness of a Rice Cooker-Steamer for Decontamination of Cloth and Surgical Face Masks and N95 Respirators[END_REF] [16] [14] [START_REF] Suen | Feasibility of Reusing Surgical Mask Under Different Disinfection Treatments[END_REF] [10], dry heat [START_REF] Li | It's Not the Heat, It's the Humidity: Effectiveness of a Rice Cooker-Steamer for Decontamination of Cloth and Surgical Face Masks and N95 Respirators[END_REF] [14] [START_REF] Xiang | Decontamination of Surgical Face Masks and N95 Respirators by Dry Heat Pasteurization for One Hour at 70°C[END_REF] [10] [START_REF] Suen | Feasibility of Reusing Surgical Mask Under Different Disinfection Treatments[END_REF], solvent [START_REF] Côrtes | Decontamination and Re-Use of Surgical Masks and Respirators during the COVID-19 Pandemic[END_REF] [12] [START_REF]Evaluation of Decontamination Methods for Commercial and Alternative Respirator and Mask Materials -View from Filtration Aspect[END_REF]. According to the different studies, dry heat seems to be the easiest method to implement. It is known that the virus dies when exposed to a 63°C environment for 4 minutes [START_REF] Abraham | Using heat to kill SARS-CoV-2[END_REF]. However, decontamination techniques can lead to a degradation and a loss of efficiency of the masks [START_REF] Liao | Can N95 Respirators Be Reused after Disinfection? How Many Times[END_REF]. The origin of the loss of filtration efficiency is not systematically explained. Indeed, this degradation may be due to a modification of the microstructure and the surface chemistry of the masks.

The objective of this study is to focus on the possible degradation of masks (and the causes of this degradation) which have undergone a dry heat treatment.

Methods

Two face masks EN 14683/2019 were heated in an oven at temperatures of 70°C, 100°C, 130°C, 140°C, 150°C, 157°C and 160 °C, for 15 minutes. Wetting angle measurements, thermal camera temperature measurements, and Scanning Electron Microscope (SEM) observations were then performed to assess the impact of dry heat on the mask structure at the micro and nanometric scale. For each heating temperature, a mask was used to perform thermal camera measurements and the other was used to perform both wetting angle and SEM measurements. After being heated at 70°C, 100°C, 130°C, 140°C, 150°C, 157°C and 160°C, the wetting angle of the masks, the surface temperature and the microstructure of the masks were observed.

The wetting angle (β on Figure 1 (a)) measurements were carried out with a tensiometer. Small squares of masks were cut (around 1 cm 2 ) in each layer. The droplet had a constant volume of 1 µL except for the second layer where the droplet had to fall because of the high hydrophobia of the second layer. The measurements were repeated five times for each layer.

The InfraRed (IR) measurements were achieved with an iPi400 camera. A Region Of Interest (ROI) was chosen (the white square presented in Figure 2 (a)) and the mean surface temperature of the ROI was measured during 40 seconds. This experiment was repeated 5 times for each mask with the same ROI and the same subject. Then, data were extracted and processed to extract the standard deviation of the temperature. The SEM images were taken with a TESCAN MIRA3 microscope. Small squares of masks were cut (around 0.25 cm 2 ) in each layer. The samples were placed on double-sided sticky carbon pads, which were sticked to an aluminum plane. The samples were then gold-coated by a sputtering device. The images were taken with an accelerating voltage of 10 kV. The statistic distribution of the standard deviation of the surface temperature (SDST) is represented in Figure 2 (c). The SDST is stable for the temperatures until 157°, when it brutally increases. Indeed, for the control sample the SDST was 0.12°C and it was 0.39°C for the mask heated at 157°C. show the first layer of the mask of the control sample and of the mask heated at 70°C. Up to 155°C no notable changes were observed, the fibers looked like the control sample. However, for the mask heated at 155°C (Figure 3 (c)) the fibers partially fused. For the mask heated at 160°C, the temperature was so close to the fusion temperature that the fibers totally fused. All of the layers fused together, making the mask very hard and unwearable.

Results

The following table synthesizes the results (a = means no notable changes compared to the control sample, a + means an increase and a × means that the measures could not be performed).

Mask

Discussion

The masks heated at the highest temperatures were deeply damaged by the treatment. Indeed, the fibers fused. Regarding the mask heated at 157°C, the fibers partially fused (Figure 3 (c)), making breathing harder for the user (which could explain the higher air flow coming outside from the mask). The mask heated at 160°C was unusable, as it had totally fused it was impossible to wear it. The increase in the airflow coming outside of the mask is not the only notable change.

The wetting angle increased significantly on the heated masks (even the one with the lowest temperature). This result can explain the source of the loss of filtration efficiency. Indeed, an increase in wetting angle means that the treated masks are more hydrophobic, which is important to prevent contaminated drops from reaching the user. However, this increase may be due to the loss of surface charges [START_REF]Evaluation of Decontamination Methods for Commercial and Alternative Respirator and Mask Materials -View from Filtration Aspect[END_REF], that is likely to modify the surface's chemical properties. Surface charges are useful, as they increase the filtration efficiency of the masks. Thus, the filtration efficiency might have decreased during the decontamination process. As the filtration efficiency was not measured, this loss cannot be quantified.

To conclude, when heated, the masks might loose a portion of their surface charges, making them more hydrophobic but less efficient. The only notable changes in airflow coming outside of the mask were visible on the masks heated at 157°C and 160°C. This variation is due to the partial (or total) fuse of the fibers. The impact of a dry heat on face mask seems to be limited to a slight modification of its hydrophobic properties. However other characterization should be performed to ensure the mask integrity.

Figure 1 :Figure 1

 11 Figure 1: (a) Measurement of the wetting angle with a tensiometer, (b) statistic distribution of the wetting angle for each mask

Figure 2 :Figure 2

 22 Figure 2: (a) ROI observed with the IR camera, (b) Evolution of the surface temperature of the mask heated at 70°C as a function of time, (c) Statistic distribution of the Standard Deviation of the Surface Temperature (SDST) for each mask

Figure 3 :Figure 3

 33 Figure 3: (a) Control sample, (b) mask heated at 70°C, (c) mask heated at 155°C, (d) mask heated at 160 °C. (The magnification is 1.12k, all the images correspond to the first layer of the mask)

Table 1 :

 1 Table of results

		SDST	Wetting	Visual	SEM
		(°C)	angle	aspect	(fibers)
			(°)
	control	0.12	130	Normal Intact
	sample
	70°C	=	+	=	Intact
	100°C	=	+	=	Intact
	130°C	=	+	=	Intact
	140°C	=	+	=	Intact
	150°C	=	+	=	Intact
	157°C	+	+	Blistered Partly
					Fused
	160°C	×	×	Fused	Totally
					fused

page 3 of 5

Acknowledgements

The authors thank the NanoLyon platform for access to the equipments. Isabel Nabeth, Thomas Gehin and Henri-Gabriel Glories are acknowledged for technical assistance.


Guillaume Dumas
email: guillaume.dumas@toulouse-metropole.fr

Valéry Masson

Julia Hidalgo

Valérie Edouart

Aurélie Hanna

Guillaume Poujol

Co-construction of climate services based on a weather stations network: Application in Toulouse agglomeration local authority

Keywords: co-construction, local authority, climate services components, user-driven sciences, Internet of things

This article provides insights into the development of climate services in Toulouse, France, based on an automated weather station network for microclimatic applications, such as urban heat island monitoring. Climate services are often thought of as a unique and complete entity that can be built by providers/sellers for users/buyers using different methods and degrees of involvement and participation. In this paper, the the local authority and its technical departments, helped by the national meteorological agency and researchers, were in charge of both providing and using the climate services. Each component, from network deployment to data production and their operational application, was directed by the local authority. Providers, users, products, and solutions were built from the ground up and developed over the last 5 years using the methodology of action research. This article discusses the possibility of understanding climate services by decomposing them into smaller components organized according to the disciplines, abilities, and challenges of each component to easily identify which actors in the local authority administrative organization can most effectively address them. Each component of the climate services based on a weather station network is discussed. This paper also describes how the governance and organization of climate services are built using action research. Co-construction processes with multiple actors encompassing multi-component projects, such as climate services, mobilize multiple disciplinary fields and require project management and organization. This article shows how the different components of the climate services in Toulouse have been integrated into different urban departments taking into consideration their competencies and their associated disciplinary fields with the goal of providing reproducible methods than can be applied elsewhere. The results indicate the real interest of urban departments in climate services. Some departments assumed responsibility for entire parts of the climate services. Their involvement reveals the complexity of truly integrating climate services as a transdisciplinary department into a public structure, in this case, the local authority. Managing the involvement and participation of all the stakeholders of the climate services implies organizing them using a governing body, even if they belong to the same organization or structure.

Practical application

Many cities are interested in climate services provided by national meteorological agencies or private companies; however, they may encounter difficulties in correctly translating the available information into adaptation decisions [START_REF] Giordano | Urban adaptation to climate change: Climate services for supporting collaborative planning[END_REF]. At the same time, some cities are more interested in mastering the production of the data themselves, particularly within the trend of smart cities and open data [START_REF] Huang-Lachmann | Systematic review of smart cities and climate change adaptation[END_REF]. For cities, the main objectives for integrating climate services are (1) to reduce the operating and purchasing costs of solutions, in particular those based on high-density observation networks, and (2) to facilitate interactions between stakeholders from the same entity and produce tailored data. However, the available literature does not address these types of needs because climate services are more often treated as a complete product in a market more than a competence or a public service for a public administration such as a city.

This paper is based on work carried out over the last 5 years in a collaboration between researchers and the local authority of Toulouse in the south of France. It sheds light on the methods used to provide the local authority with internalized climate services based on, among other things, a weather station observation network. This paper is an application of the ongoing theories of the coproduction of climate services [START_REF] Vincent | What can climate services learn from theory and practice of co-production?[END_REF][START_REF] Bremer | Toward a multi-faceted conception of co-production of climate services[END_REF] in the particular case where the administration of a local authority covers all aspects of the users and producers of the data, being more than an "external factor" 1 to the development of the climate services [START_REF] Stegmaier | Reflexive climate service infrastructure relations[END_REF]. This paper is organized into two parts. The first focuses on how a climate service and all its components, which can be complicated to identify in their entirety, can be incorporated into a local authority organized into departments with specific competences. This paper seeks to decompose and deconstruct climate services based on networks of observations into distinct objects of study attached to separate but interacting disciplinary fields and related competences. This approach is built on a bibliographic classification, based on the World Meteorological Organization conceptualisation of urban climate services (Grimmond et al., 2019). Consequently, each revealed competence allows the department of the local authority that will be in charge of each component of the climate services to be chosen wisely. The second part describes the collaborations between researchers and the local authority that call for methods relating to participation and, in particular, to co-construction. The aim of this study is to establish the governance and organization of the climate services in a local authority administration. This paper therefore proposes a reproducible and interdisciplinary approach to the implementation of an urban climate service based on a meteorological network into a structure organized by the competences. It aims to mobilize methods put in place by research in urban climatology directed toward operational urban planning with the objective of participating in scientific debates concerning the development of urban climate services.

Introduction

Decades of work already exist concerning the concept of climate services [START_REF] Vaughan | Climate services for society: origins, institutional arrangements, and design elements for an evaluation framework[END_REF][START_REF] Changnon | Examples of applications of climatic data and information provided by state climate groups[END_REF]. Throughout this period, the meaning of climate services has evolved from a focus on improving access to climate sciences and data to a concept of integrated services, that is, informed users and climate science-driven applications [START_REF] Vaughan | Climate services for society: origins, institutional arrangements, and design elements for an evaluation framework[END_REF]Lourenco et al., 2016;[START_REF] Bessembinder | Need for a common typology of climate services[END_REF]. In this sense, climate services are meant to establish a connection between two distinct universes: scientists, who are usually the providers of these services, and society, i.e., the users [START_REF] Mcnie | Delivering climate services: Organizational strategies and approaches for producing useful climate-science information[END_REF].

Because some connection issues remain between service providers and users (Lucio and Grasso, 2016;[START_REF] Buontempo | Climate service development, delivery and use in Europe at monthly to inter-annual timescales[END_REF], multiple methodological frameworks, structures, guidelines, and scientific papers have been produced to help correctly establish the link between providers and users. We can cite as a flagship the World Meteorological Organization (WMO) and the global framework for climate services (GFCS) [START_REF] Hewitt | The global framework for climate services[END_REF]. As one of the many guidelines available, we can evoke the one designed for cities that we use as a reference point in this paper: Guidance on Integrated Urban Hydrometeorological, Climate and Environmental Services (Grimmond et al., 2019). Institutional non-climate-related stakeholders are also involved, such as the European Commission through its H2020 Research and Innovation Program, which published in 2015 a European roadmap for climate services. With more and more papers on climate services addressing the topic of connection issues, research concerning the interface linking users and providers has expanded considerably over the last seven years [START_REF] Lugen | Framing Climate Services: Logics, Actors, and Implications for Policies and Projects[END_REF]. To describe these relationship between users and providers, terms such as participation, co-construction, and collaboration are used [START_REF] Vincent | What can climate services learn from theory and practice of co-production?[END_REF]. However, even in these studies, the users are often considered to be an "external factor" instead of being a part of the process of building climate services [START_REF] Stegmaier | Reflexive climate service infrastructure relations[END_REF]. The fact that the users often do not have a sufficient level of climate knowledge (concerning for example what types of data, technologies, products, and stakeholders exist) separate them from the development of the services themselves. This can lead to a paradox with respect to the wish to have user-driven climate services and justifies a market approach to develop the range of actors involved in the development of climate services [START_REF] Cavelier | Conditions for a market uptake of climate services for adaptation in France[END_REF].

In 2016, the local authority of Toulouse in the south of France decided to build its own climate services, starting with an automatized weather station network to monitor the urban heat island (UHI) effect. The local authority, taking advantage of the physical proximity of climate specialists (from the national meteorological agency and the university), built a partnership that allowed work on the following scientific question: "How can climate services, in their entirety, be integrated in a user-driven methodology through co-construction processes into a structure-here a local authority-to produce climate-related data for its own specific needs?" This paper, after briefly presenting the local context of the study , proposes a methodology in which climate services are decomposed into components embracing the interdisciplinary fields inherent to their nature (Section 2). This deconstruction of climate services allows a selection of different stakeholders of the local authority for collaborations, building the governance of the climate services. This methodology of governance construction is presented in Section 3 and is here applied to the specific case of a weather station network but is reproducible with any other type of climate service.

Local context

Because of their capacity to concentrate populations, networks, and activities, urban areas have an increased vulnerability in the face of climatic events, whether ordinary or not. Cities then develop and organize their interventions around so-called adaptation and mitigation strategies. This is about both limiting the risks and reducing greenhouse gas emissions. To better calibrate these responses, it is necessary to control, assess, and calculate climate risks and vulnerabilities [START_REF] Cortekar | Why climate change adaptation in cities needs customised and flexible climate services[END_REF][START_REF] Baklanov | From urban meteorology, climate and environment research to integrated city services[END_REF]. Local authorities, administrations, and stakeholders of the urban fabric then try to respond to legislative frameworks and to local, national, and international political ordinances.

In France, there is no legal obligation for a local authority to engage in any type of climate monitoring. The only obligation for a climate plan exists in laws related to the Grenelle de l'Environnement (the August 3, 2009, "Grenelle 1" law and the July 12, 2000, "Grenelle II" law). Climate plans are divided into two components focusing on mitigation and adaptation to climate change. Air quality and energy consumption management are also taken into consideration. Climate change mitigation concerns efforts to control greenhouse gas (GHG) emissions into the atmosphere. This first section of these documents includes particularly well-established regulation tools such as GHG assessments (compulsory for communities with more than 20,000 inhabitants), even though several calculation methods exist. The second part, which is still ill-defined, focuses on the notion of adaptation to climate change.

To provide the adaptation part of the climate plan with a strong tool, in the same way as the GHG assessment, the local authority of Toulouse, within its department in charge of the Climate Plan and supported by its elected representative, wanted to establish urban climate services. The needs expressed concerning these services related in particular to internally produced data adapted and used in conjunction with other documents (e.g., the master plan and building permits). The desired climate services first need to characterize and map areas of lower temperatures and urban overheating. Second, these services need to provide indicators to monitor the impacts of urbanization on the local climate. Finally, they need to thematically and locally complement the climatological profile regularly provided by the national meteorological agency (Météo-France).

Accordingly, the local authority and climate researchers from Météo-France and the University of Toulouse, both based in Toulouse, built a partnership. The aim was to introduce the expertise necessary to develop a weather station network producing near real-time data for the local authority and the entire data treatment chain. This means that all the components of the climate services should, ultimately, be implemented in the structure of the local authority.

Methodology: decomposition of components to identify the necessary competences in the departments of the local authority

Climate services are often treated as a "black box," or as a single object; however, such services are complex and contain many interdisciplinary retroactive processes. Climate services based on weather stations, for example, imply knowledge necessary to choose measurement sites, choose telecommunications technologies, or to provide user-friendly data visualization. For a local authority, which works with a structure organized into departments related to competences, climate services need to be decomposed into multiple parts related to those competences. Then, each part can be redistributed to the different relevant departments of the local authority (Fig. 1). This constitutes the first part of the methodology described in this paper. We used the component organization for climate services provided by the WMO (Grimmond et al., 2019) and separated the components related to each disciplinary field into stakes, norms, and standards. We use this methodology for our case study (an observation-based service) to demonstrate how it can be operationally applied.

Then, once every component (and associated required competence) of the service is identified, we work with the local authority departments to discuss how they will oversee each identified component. This leads to the governance, which will discussed in detail in the second part of the paper (Section 3), with the territory of the agglomeration of Toulouse, France, as an example. The departments are hierarchical and organized depending their participation levels and their involvement in their dedicated component . The paper general methodology is described in Fig. 1.

Decomposing theoretical climate services into several operational parts

Climate services are often associated with a clear frontier between users and providers, between buyers and sellers, between demand and supply, and between science, society, and policy [START_REF] Harjanne | Servitizing climate science-Institutional analysis of climate services discourse and its implications[END_REF]. In the case of this paper, these frontiers are less distinct. The main user and main provider are the same entity, the Department of Environment and Energy of the Toulouse Metropole, in charge of the climate plan. Therefore, the following climate services were envisaged as a sum of components linked to specific competences instead of as an entire product.

Translating general urban climate service components into weather stationbased urban climate service components

The first step was to decompose the climate service into a sum of multiple smaller components using the WMO structure for climate services. Once this step was complete, we translated the component to our specific case, that is, a climate service based on an observation network, to identify the competences that were needed to implement an operational climate service. Accordingly, we used state-of-the-art methods in each of the disciplinary fields involved in each component. On the form, it is linked to an organized state of the art, but with respect to the content, it is more a guideline to enable urban actors or other to approach each component according to their issues, objectives, and standards.

We started using the WMO integrated urban service (IUS) general components, which are organized via a retroactive process (Fig. 1). This dictates a relationship between the users (and their needs) and the providers.

Ten key points define the structure of an IUS, and these points are organized into four interdependent components.

• The first core component consists of data production with three subcomponents acting in interaction with each other: -Database and Sharing; -Observation/Monitoring; and -Modeling and Prediction. • The next three components show the effective use of the data by the users:

-Applications; -Decision Making, Support System, and Human Response; and -Communication and Outreach. • The following two components are framing:

-Research and Development; and -Capacity Development.

• The remaining components materialize the retroactive process, that is, the component "Evaluation, Assessment, and Impacts" returns to the starting component "Understanding of Needs and Partners." • Fig. 2. Schematic of the components of an integrated urban service system (Grimmond et al., 2019).

As shown in Fig. 2, IUS development requires interactions between the users and the providers (sometimes called the "suppliers") as a co-construction process. This is shown by the bidirectional arrows in the structure. This follows recommendations to strengthen the link existing in climate services between scientists and non-scientists [START_REF] Hewitt | The global framework for climate services[END_REF][START_REF] Baklanov | From urban meteorology, climate and environment research to integrated city services[END_REF]. This is a key point as many studies rank the collaboration aspect, including co-construction, as being the main criterion to successfully create and perpetuate an IUS [START_REF] Mcnie | Delivering climate services: Organizational strategies and approaches for producing useful climate-science information[END_REF][START_REF] Christel | Introducing design in the development of effective climate services[END_REF]Grimmond et al., 2019). The goal is to avoid the usual process of production delivery from sciences to society commonly described as a "loading dock" or linear model [START_REF] Cash | Countering the loading-dock approach to linking science and decision making: comparative analysis of El Niño/Southern Oscillation (ENSO) forecasting systems[END_REF]McNie, 2011).

Co-construction needs to be distinguished from collaboration. Co-construction is an interdependent relationship [START_REF] Panet-Raymond | Partenariat ou pater-nariat?: la collaboration entre établissements publics et organismes communautaires oeuvrant auprès des personnes âgées à domicile[END_REF] and here is understood to be a social process of the construction and sharing of long-term relationship goals (Levesque, 2001). Co-construction is balanced by multiple points including legitimacy (between stakeholders involved), interests ( financials, pedagogical, etc.), and mutualizing (Audoux and Gillett, 2011).It is strongly related to the IUS component "Understanding of Needs and Partners." Today a lot of literature is dedicated to the co-construction of climate services, from theoretical concepts to application cases, as shown later in Sections 2.2.5 and 2.2.6.

The multiplicity of partners in a co-construction process implies interdisciplinary and transdisciplinary work and some project management [START_REF] Webber | Putting climate services in contexts: advancing multi-disciplinary understandings: introduction to the special issue[END_REF]. In this paper, interdisciplinary refers to the integration of disciplines in terms of, for example, methods, models, and data, while transdisciplinary refers to cooperation across scientific and mostly non-scientific stakeholder communities.

For an IUS based on observations, every component must be discussed when co-construction begins. Because the observation component is the core component of this type of IUS, from which the production of data will result, this process could start with building the following three components:

• Observation/Monitoring, which can be divided into three subcomponents: choosing measurement sites, sensor types, and telecommunication types;

• Database and Sharing, which are already divided and refer to how the data are organized and available; and • Applications, which embody the effective use of the data.

The transdisciplinary and interdisciplinary aspects of co-construction can be observed when each component is connected to several disciplinary fields. For example, the two components Observation/Monitoring and Database and Sharing are composed of six main distinct disciplinary fields. The organization of the co-construction process applied to these components, and their associated disciplinary fields, is shown in Fig. 3. Figure 3 describes a retroactive process. Once the observational needs are determined, a succession of steps must be taken.

• The quantity and position of the measurement sites are discussed in the Observation/Monitoring component. The type of sensors and the technologies for transmitting the data are also determined. These three subcomponents are linked together. For example, for a given budget, it needs to be determined if the focus will be on the number of sensors or on their quality. • In the Database and Sharing component, questions focus on how to store the data and how to make them available and understandable to specific users. Applications are based on the form of data delivery. The boundary between this component and the Observation/Monitoring component is permeable. For example, the frequency of sampling is determined in the "real-time/automated data transmission" subcomponent but will be limited by the storage capacity and its organization. • Applications result in new demands or needs as users manipulate the applications and ask for improvements or novel functions. The providers can also propose technologies or new and improved observation systems. This component is not related to only one main disciplinary field specifically, we discuss it through the prism of the interdisciplinarity as it question multiple aspects of climate services.

To facilitate and conceptualize this co-construction process of an IUS based on weather stations, Tables 123456present several references that clearly express the different components of Fig. 3. These references include guidelines, experience feedback, reviews, and standards. Some references come from organizations such as the WMO for climatology. All of these references help build an IUS because they indicate the specificities that each user and provider need for each component. Choosing where to locate meteorological stations is an important step in mobilizing urban studies and applied urban climatology. The urban heat island (UHI) effect is a well-known phenomenon, particularly the canopy layer (UHIcl) type. The canopy layer corresponds to the external air that extends from the surface (e.g., a road, garden, or car park) to the building top. UHIcl is evaluated according to the difference between the temperature of the air in the city and the corresponding height in the near-surface layer in the countryside (Stewart, 2011). This is the most important and commonly studied type of heat island (Stewart, 2011) because it describes the characteristics of the air where people live.

Six components of urban climate services based on a weather station network 2.2.1 Choosing measurement sites

To observe this microclimatological effect, stationary or mobile thermometers, preferably in radiation shields, are used. In a stationary approach, each probe is usually placed at representative sites in urban and rural local climate zones (Stewart andOke, 2009, 2012). A sensor can also be mounted on a vehicle, which would constitute a mobile approach to studying small-scale spatial variations in the temperature.

Moreover, a weather station network can be deployed in various forms or shapes [START_REF] Robinson | The London Meteorological Monitoring Network[END_REF]Muller et al., 2013), as described below.

• A systematic network has a point for every square of a grid. Such a network could be interesting for a city with large identical urban areas but is not relevant if there is high variability in the urban forms. • A radial-type network corresponds to a star shape with samples along transects of each branch of the star. Such a network is useful to determine the temperature gradient of a city starting from the downtown area and extending to peripherical areas. • A random network, or a semi-random network with random samples, can occur when amateur weather stations are used because there is no one authority in charge of the overall placement of the network. This type of network can also occur when the sites are imposed. Some considerations are less constraining, such as using only traffic light poles. Everything depends on the density of the potential authorized sites and the number of sites that can be equipped. For example, if there are 10 stations and there are only 10 schools, the network is fully random (from a meteorological point of view), while if there are 5 stations for 10 schools, then the network is semi-random. The boundary between semi-random-type and gradient/transect-type networks can be very blurred. • In political networks, administrative boundaries impact the sample positions.

• Gradient/transect-type networks have gradient samples at different densities or along lines.

Such networks can look random; however, every location corresponds to a specific choice.

The transect method can represent the thermal amplitude between a city center and its surroundings following different axes and thematics [START_REF] De Lapparent | Pseudovertical temperature profiles and the urban heat island measured by a temperature datalogger network in Phoenix, Arizona[END_REF]. Such a network can follow a river or follow a succession of increasingly dense industrial or residential areas.

In any case, well-chosen measurement sites will determine the sample quality of the network in terms of the representativity of their immediate environment.

Table 1 shows different types of bibliographic references concerning these subjects. The standards are described as guidelines. These documents explain how to interpret urban areas from a climatological point of view using a systemic approach. The WMO is one of the main providers of this type of document.

Experience feedback allows a network to be evaluated, to compare its characteristics with standards via a point of view anchored in its environment (e.g., geography or policy) with the relevant specificities (e.g., economics or density).

The third type of reference consists of reviews, which allow networks to be compared to each other.

A user can then quickly see the varieties and complexities of networks and look for a network corresponding to stakes relevant to that user.

Urban studies are not presented here directly. However, they play a role in obtaining other readings in a territory. The type of population, future real estate operations, and urban renewal are some examples of points for urban stakeholders to consider when choosing measurement sites appropriate to the evolution of the urban area studied. The choice of sensor depends on the physical variables observed; this is relevant to the disciplinary field of electronics. Most weather station networks used for UHIcl studies are only able to measure the temperature or the temperature and moisture data. In France, the city of Dijon has installed more than 50 temperature and moisture probes since 2014 as a part of the MUSTARDijon research project [START_REF] Richard | How relevant are local climate zones and urban climate zones for urban climate research? Dijon (France) as a case study[END_REF][START_REF] Richard | Les Local Climate Zones face à la canicule de 2018 à Dijon[END_REF]De Lapparent, 2015). Few of these probes include a complete range of sensors including rain, temperature, moisture, pressure, wind speed and direction, and solar radiation. In France, excepting the present study, only the University of Rennes possesses a complete network of approximately 30 weather stations at the intra-urban scale [START_REF] Foissard | L'îlot de chaleur urbain et le changement climatique: application à l'agglomération rennaise[END_REF].

Choosing sensors

Measuring more than just the temperature allows a network to be used for deeper analyses of the relationships between the UHI and other meteorological effects and enables other applications in addition to UHIcl studies [START_REF] Chapman | The Birmingham urban climate laboratory: an open meteorological test bed and challenges of the smart city[END_REF]. The quality of the sensors themselves vary from amateur to professional. For example, participative science and crowdsourcing data sometimes use amateur weather stations such as Netatmo [START_REF] Napoly | Development and application of a statistically-based quality control for crowdsourced air temperature data[END_REF]. The quality of such data can fluctuate and demand a less dense and more accurate network for validation [START_REF] Meier | Crowdsourcing air temperature from citizen weather stations for urban climate research[END_REF], but the amount of data is often sufficient [START_REF] Chapman | Can the crowdsourcing data paradigm take atmospheric science to a new level? A case study of the urban heat island of London quantified using Netatmo weather stations[END_REF].

Each sensor has its own technical characteristics. There are many criteria to take into consideration, including the accuracy and lifetime of a sensor. Moreover, it must be determined if the technical solution will be made using a subcontractor or a pre-existing ready-to-use product. The costs can vary drastically, and partners must communicate to adjust the products to their specific needs. The cited references can be used to compare and analyze different technical solutions with respect to their qualities and limitations (Table 2). A weather station network is related to telecommunications technologies via two aspects.

Choosing telecommunications technologies

• The first aspect is its characteristics as an Internet of Things (IoT) structured object.

Telecommunications technologies mobilize new concepts and categorize different components of a network. This aspect involves certain questions. Are the terminals of the network able to receive information? Are the gateways able to communicate with each other? • The second aspect concerns the telecommunications system used to transmit the data. This is strongly related to the electronics and informatics. Data transmission can be performed using a manual or an automatic routine. Depending on the definition of the network used, a manual transmission type is usually referred to as a "collection sensor." This means that, until someone comes to collect the data, the data are stored using a datalogger. This is the method used by the MUSTARDijon project and the HiSAN network in Taiwan [START_REF] Chen | The application of a high-density street-level air temperature observation network (HiSAN): Dynamic variation characteristics of urban heat island in Tainan, Taiwan[END_REF]. Some networks, conversely, can provide real-time data with automatic weather stations, such as the network in Szeged, Hungary [START_REF] Skarbit | Employing an urban meteorological network to monitor air temperature conditions in the 'local climate zones' of Szeged, Hungary[END_REF]. Additional questions include if the network is wireless, if it has a long range, and if it has sufficient energy if connected to a solar panel.

For both aspects, standards, including ISO, exist and must be respected. These standards may change from one country to another. For example, Europe is regulated by the European Telecommunications Standards Institute. Organizing a database requires focusing on both the methods and the tools and is related to informatics.

Organizing databases

• The methods concern how the data content are organized with respect to their type. Satellite data and observational data require specific metadata and can require some amount of storage management. For example, guidelines and standards provided by the WMO enable data to be homogenized and shared in a common format used in climate sciences. • The tools depend on the software architecture of the desired data platform, and there are several studies that provide comparisons of various technologies. Criteria that should be examined include the virtual space storage efficiency, Internet portal utilization or speed of information transmission, and access. The delivery of data consists of both aesthetics and substance. Where climate data are concerned, some aspects of the results need to be refined. The reliability, accuracy, political sensitivity, and limits of the data are all criteria that need to be taken into consideration. Experience feedback is a way to address these issues. However, there is a lack of comparative reviews concerning the delivery of climate data in climate services.

Delivering data

An interesting point here is the appearance of the "design" disciplinary field. The delivery of climate services to users is often associated with a visualization interface, and there are studies available concerning this specific aspect. This aspect can also serve as a point for exchange and coconstruction and can refer to design study methodologies [START_REF] Sedlmair | Design study methodology: Reflections from the trenches and the stacks[END_REF]. Data visualization in climate services is still a field of active research. This may be due to the relative novelty of the exercise. One point to remember is that the variation range of the data visualization and the data delivery characteristics correspond to the variation range of the users. In other words, the more the user's needs and applications vary, the more the data will be shaped in different forms. Last, but not least, climate services are transdisciplinary projects, including multiple actors involved with climate science production and delivery. As expected for an emerging field, many recent references are available to conceptualize and assess the goals and stakes of projects through this transdisciplinarity prism; however, there is less experience feedback concerning their application.

Climate services transdisciplinarity

Guidelines exist to develop these services, including co-construction methods. Experience feedback can give examples of climate services applied to specific territories via multiple aspects (e.g., observations, delivery, and data transmission).

In addition, researchers have studied the development of climate services as general science services [START_REF] Harjanne | Servitizing climate science-Institutional analysis of climate services discourse and its implications[END_REF], questioning their forms, stakes, utilities, languages [START_REF] Vaughan | Climate services for society: origins, institutional arrangements, and design elements for an evaluation framework[END_REF][START_REF] Lugen | Framing Climate Services: Logics, Actors, and Implications for Policies and Projects[END_REF] and applications.

Co-construction applied to urban departments in Toulouse

Here, we present an application of this conceptual framework to the co-construction of an IUS based on observations in the Toulouse metropolitan area. Indeed, this section presents the expressed needs of the urban departments, their participation levels, and the final climate services governance.

The governance (Fig. 4) and participation levels (Table 7) illustrate how the urban departments are connected to each component of the network and how they interact.

We first explain the organization of the local authority and the three participation levels we used to describe the form of interaction with the urban departments. Once the list of stakeholders is presented (including external partners as private companies), we structure the climate services using a governance chart where only the urban departments appear because they are the owners of the climate services.

Organization of the metropolis

This project involved various partners at different levels of involvement and participation, including urban departments from the Toulouse Metropole and public organizations, such as NMHS (Météo-France and its national climate research center), universities2 , and private companies (mostly equipment suppliers). Public organizations provided economic support, and some organizations were interested in developing softwares solutions around the data produced, such as the Deposits and Consignments Fund. Several private companies showed similar interests (e.g., Capgemini).

Because the data were intended to be freely accessible on an open data platform3 , external software developers were not directly related to the climate service. The NMHS and the universities bring expertise and knowledge to the co-construction process, while the urban departments are the main actors and stakeholders. Indeed, because they own the observation network, the urban departments play multiple roles, including as product owners, users, and data producers.

The Toulouse local authority is divided into departments, themselves subdivided into smaller subdepartments. For example, there is the Environment and Energy Department (EED), which manages climate plan, air quality, and sound quality teams. There are also specific teams in charge of rivers and hydrological structures. In France, there is no legislation to concretely organize a metropolitan area, just a list of possessed competences that are described within the law4 (Le [START_REF] Bras | Métropoles en chantiers[END_REF][START_REF] Chabrot | La métropole dans les réformes territoriales françaises[END_REF]. Each department can be organized by the mayor of the city and its board as they see fit. The challenge therefore is to identify where the competences are in each department with respect to the components of the IUS.

Participation levels

The participation levels of the urban departments are not homogeneous. Some are only consulted, others are coordinated with, and still others participate in the co-construction. These terms reflect the different levels of participation. Here, we develop the terms we used to define three levels of participation: consultation, coordination, and co-construction.

• Consultation (first level) In consultation, a need is expressed without continuous exchanges, only when the work is finished are the results presented. Take, for example, the departments consulted concerning the choice of site locations for measurements. These departments have specific needs that correspond to an envisioned application and to particular locations. For example, actors in Green Areas want to observe data from parks, in particular during the summer, to compare temperatures in different parks. Meanwhile, actors in Territorial Centers prefer to place sensors in urban projects, renovations, or new neighborhoods to monitor temperature changes. Their needs are considered but, because there is no feedback to them concerning the validation of the locations, their role is limited to consultation.

• Coordination (second level) At the second level, there is coordination. Here, needs are expressed and the results are shown, followed by the collection of opinions, however, without any obligation to take these opinions into account. In this category, we see departments that are involved for the selection of sensors for specific applications. Requested locations can considered and evaluated on a case-by-case basis for validation with the departments. For example, the department concerned with construction and new buildings may request sensors located on school grounds to compare outdoor temperature data to indoor data from their sensor network. Coordination is a intermediary level of participation, were the relationships are discontinuous but the exchanges and the implications from the contacted departments are consequents.

• Co-construction (third level) The final level is co-construction. Here, needs are expressed and exchanges are continual until a solution is found. This concerns several components. The suggestions of the involved urban departments significantly impact the structure of the IUS. They may change the size of the network, its objectives, or any other specifications. For example, the Streetlights Department could invalidate the entire network if its needs are not met. The network must comply with European directives regarding wireless emissions; however, the weight of the stations and their mounting brackets cannot jeopardize the stability or integrity of the streetlight poles.

3.3.Work organization

For all levels of participation, the necessary exchanges cannot be completed in a single meeting with all the urban departments in the same room. Indeed, these departments do not have the same needs. Consequently, meetings need to be spread out over several months with the relevant people in each department to build an interface where feedback is appreciated and solicited. Note that each urban department may mobilize a particular disciplinary field; therefore, the language of the meetings needs to be adapted to each discussion. The project may therefore be constantly renegotiated, especially if its content and contours are co-constructed in a dynamic process. In meetings, there was an attempt to emphasize the multi-faceted co-construction prism developed by [START_REF] Bremer | Co-production in climate change research: reviewing different perspectives[END_REF][START_REF] Bremer | Toward a multi-faceted conception of co-production of climate services[END_REF] because discussions covered multiple topics. In addition, we benefitted from being an agent of the local authority. This facilitated our connections and links with the urban departments.

As an example of co-construction, one focus of the Numerical Department of the Toulouse metropolitan area was to integrate any data into their open data application and their future "Artificial Intelligence Data" internal application. The weather station network provides a proof of concept for their platform, which is presently under construction, and they integrated the storage of the data components into their Geographic Information System platform architecture. Discussions with the Numerical Department cover topics such as software, data organization according to their point of view, and their capacity. It is important to communicate in appropriate terms when specific points arise with specific departments. During work with the Numerical Department, design and graphics questions were also evoked, which is an aspect that has already been studied in the scientific literature of climate services [START_REF] Christel | Introducing design in the development of effective climate services[END_REF].

The results of the co-construction process, and in general any participation level, reveal the real expectations of the contacted departments in addition to their aspirations. The number of partnerships and urban projects related to the observation network has grown as the study has progressed. This has not really modified the technical solution itself; however, it has changed the extent of the applications of the network as a tool for many departments. The main consequence has been an increase in the number of weather stations in the network. To illustrate this size modification, two projects linked to the network are presented below.

• The first is an urban planning project led by the Garonne River and Canals Department, which is a sub-department of the EED in charge of the Garonne River, the Canal du Midi, and the Canal de Brienne, the three of which run through the city. This department wants to measure the impact of future renovations along both sides of the Canal du Midi. They plan to remove a large amount of vehicular traffic, create larger green spaces, and plant thousands of trees. Currently, the project is in the design phase and there will be a five-year construction period from 2021 to 2025. Therefore, 10 stations have been bought and specifically designed to observe this operation. • The second is both an urban planning project and a scientific project: the transformation of an island in the center of Toulouse into a park. Currently, this island is home to a huge parking structure and an exhibition center. This is a location that includes a large amount of impermeable surfaces and few trees that will be transformed into an urban park.

Approximately 10 stations are related to this project, which is called the "Project LIFE île du Ramier" or the "LIFE project Ramier Island." The goal is to conduct microclimatic simulations with high-resolution models in combination with additional meteorological stations to assess the impact of future changes on the region.

Altogether, the project involves 11 departments (Table 7). Some departments (as future users) are directly concerned by the choices of the measurement sites and expect results from the "sharing" component for specific applications, while other departments participate in meetings but are still waiting for results to prove the utility of climate services as applied to their technical fields. The "data transmission," "data storage," and "sharing" components are strongly connected to the Numerical Department (as climate service user interface developers). The "data transmission" component is also related to the Streetlights Department to ensure compatibility with their networks and to validate each pole.

In parallel, three departments are waiting on the results from other departments either to evaluate the climate services or to start developing their own services.

• The Innovation Department is in charge of overseeing all "smart-city" projects (they are a sub-department of "Modernization" in the Numerical Department). • The Regulation Department is in charge of all urban areas built by public authorities and the writing of urban planning documents. • The Civil Security and Major Risk Department is awaiting protocols from the EED to efficiently manage heatwaves.

Table 7 shows all the partners involved in the climate services and their associated participation levels.

Governance of the urban climate service

Co-construction involves multiple urban departments; however, they are not hierarchically organized in the metropolis. A hierarchy needs to be created to direct the IUS and its components.

In addition, even if some departments may only be integrated into the consultation or coordination of specific components of the network, their role can still be crucial and highly hierarchical.

Figure 4 shows the governance of the climate services. To construct this governance, we used two criteria: the participation level and the dependency of a component on a department. The dependency can be:

-Complete, which means that, if the department stops its work on the IUS, the component also stops;

-Partial, which means that the department is not fully in charge of a component, if it stops, the component can still work; and -Null, which means that the department, even if it is involved in a component with any level of participation, has no impact on that component if it leaves the climate services.

The hierarchy was constructed by prioritizing the dependency criterion over the participation. For example, a department partially in charge of a component and involved in coordination processes will rank higher than a department with a null dependency but with co-construction involvement. Therefore, the governance chart contains five levels in our case (Fig. 4a). Each level is associated with the name of the department involved, its operational needs, and the climate service component with which it is interacting.

The first level is for co-construction and total dependency. The second is for coordination and partial dependency (Fig. 4b). Levels 3, 4, and 5 are for co-construction, coordination, and consultation, respectively, with no dependency (Fig. 4c).

Conclusions

This paper described work done on the expansion of climate services for the Toulouse local authority in partnership with Météo-France and local universities. Its main objective was to show how the different components of climate services can be integrated into urban departments using the co-construction process. In this case, it was the development of an automated weather station network in real time for microclimatological studies.

From our point of view, as well as that of the metropolis, co-construction is a long-term process, here relating to a long-term project including multiple stakeholders over multiple years. This work was developed in the framework of a three-year PhD project. In the two previous years, the local authority also funded a masters-level internship and a student group to conduct a feasibility study and to find technical solutions. Currently, the local authority provides funds for a full-time position in the Climate Research Center to finalize the implementation of the climate services. At the same time, they have started an audit to evaluate the possibility of building a specific IoT team and, in two years, recruiting individuals for one or two full-time positions to internally produce climate information, achieving an internalization of the climate services competence. This demonstrates how the integration of climate services via an automated station network into the administration of a local authority and its urban departments is an exercise mobilizing multiple disciplinary fields.

This experience demonstrated that co-construction can be divided into the following three steps.

• First, there is the "birth" of the project, where the aims, goals, possibilities, and capacities of each stakeholder need to be defined for each partner even if they are clear to the stakeholders themselves. This step involves the carriers of the project. • Second, there is the "growth" or development of the project, where more partners are integrated into the process, the specificities become more detailed, and the terms of providing and using the services are conceptualized. In this step, the disciplinary fields enable the clear separation of what is relevant with respect to good practice, standards, or needs, as well as the involvement of specific urban departments with respect to their technical domains. • Third, there is the "maturity" of the project where the deliverables are realized. The project can stop at this step or can continue into a retroactive structure where feedback evaluations are made and the process of growth continues.

For each step, two parts emerged.

• The first is an acculturation part, where each partner comes with their own specificities, such as their own language, needs, and goals. • A second part follows where both sides, the providers and the users, are connected. Their languages are common, and their separate capabilities are merged into one.

For example, in this project, there was an important acculturation step to explain to the urban departments the differences between remote sensing and air temperature in ground level UHI studies during the birth step of the project. Indeed, the air-temperature measurement method needed to be justified because of its large cost compared to remote sensors, which do not observe the same variable. This acculturation needed to occur because many other cities simply use surface UHI studies, and the urban departments were already familiar with these technologies. Moreover, in the same local authority, some urban departments were already using surface UHI studies with the belief that they were using air-temperature data. This resulted in misled decisions and communication issues. This point also informed the climate scientists of a gap in the communication associated with their research. After acculturation was complete, the connection step occurred. This was the moment when the urban departments in the growth step of the project directly asked for new measurement sites, specifying if they served thematic or transect studies, the important variables to observe, and even sometimes proposals for lampposts and local representatives to deploy the materiel. Acculturation also occurred in the other direction, from the users to the providers. For example, in the maturity step of the project, the Numerical Department explained how their internal data architecture worked and what was possible under what conditions.

Today, the main interest is to continue to capitalize on this work and on the network capacities and to prove its ability to last and to be pertinent to urban planning, which means strengthening the links between the urban departments. The work around the creation of the network has already brought urban departments together to a surprisingly level, proving its value with just this aspect, prior to obtaining any results. This validates the co-construction process, showing that meetings can have a greater value than their goals. The metropolis has financed a three-year position to continue work on the network from both research and operational points of view.

At this point of the IUS structure, the co-construction process can be considered a success. A strong choice was made by the local authority to internalize the service instead of buying a service solution from a private company or the NMHS. This point strongly diverged from a market approach for climate services. In addition, this particular point made this IUS a complete integrated climate service as a new competence for the local authority, where the role of the NMHS is only to provide knowledge and act as a scientific organism to validate a desired tool. This is a win-win relationship. In effect, urban department studies will be supported by science in exchange for access to data from a complete network built at scientific gold standards but maintained by urban departments with more significant technical support.

Our work was designed as a reproducible approach for any other city or structure that wants to develop its own climate services and does not know where to start or the scale of the task. We strongly hope to see other cities become empowered, becoming climate service and knowledge providers, in the same way they develop their competences in other fields. In addition, their feedback will provide interesting insights into methods to deal with network maintenance and management over long periods, which are key to the success of these types of climate services.

Fig. 1 .

 1 Fig. 1. Methodology to translate general climate services into multiple components to integrate them as hierarchical and organized climate services into the organization chart of a local authority.

Fig. 3 .

 3 Fig. 3. Components and disciplinary fields of climate services built for UHI monitoring using a weather station network.

  Fig. 4. (a) Governance based on the hierarchy and participation level of the departments. The department type and name and the range of actions in the climate services is indicated. (b) Levels 1-3 of the governance using co-construction. (c) Levels 4 and 5 of the governance using coordination or consultation as defined in the text.

Table 1 .

 1 Choosing measurement sites. World Meteorological Organization, Guide to Instruments and Methods of Observation Volume III -Observing Systems, 2018, p.371-398 • Oke, T.R., et al. Initial guidance to obtain representative meteorological observations at urban sites. 2006 • Oke, T.R., Mills, G., Christen, A., et al. Urban climates. Cambridge University Press, 2017

	Subject	Purpose	Example
	Guidelines Provide standardized	•
		methods to deploy
		a network

•

Baranka, G., BOZÓ, L., KOMAC, B., et

al. Urban Heat Island Gold Standard and Urban Heat Island Atlas. In : Counteracting Urban Heat Island Effects in a Global Climate Change Scenario. Springer,Cham,2016.p.41-7070. Experience feedback Present networks • Chapman, L., Bell, C., & Bell, S. (2017). Can the crowdsourcing data paradigm take atmospheric science to a new level? A case study of the urban heat island of London quantified using Netatmo weather stations. International Journal of Climatology, 37(9), 3597-3605. • Warren, E.L., Young, D.t., Chapman, L., et al. The Birmingham Urban Climate Laboratory-A high density, urban meteorological dataset, from 2012-2014. Scientific data, 2016, vol. 3, no 1, p. 1-8. Review of networks Compare networks • Muller, C.L., Chapman, L., Grimmond, C.S.B., et al. Sensors and the city: a review of urban meteorological networks. International Journal of Climatology, 2013, vol. 33, no 7, p. 1585-1600. • Stewart, I.D., A systematic review and scientific critique of methodology in modern urban heat island literature. International Journal of Climatology, 2011, vol. 31, no 2, p. 200-217.

Table 2 .

 2 Choosing sensors.

	Stake	Type of sensor	Sources of evaluation/comparison	Examples
				• No, expert guide. The Davis Instruments Vantage Pro2 wireless AWS-an independent
				evaluation against UK-standard meteorological
				instruments. 2009
	Provide evaluations of sensors to help in choosing technologies	• Professional sensors • Semi-professional sensors • Amateur sensors	• Independent reviews • WMO or NMHS observation department reviews • Electronics company reviews (grey literature)	• World Meteorological Organization, Guide to Instruments and Methods of Observation Volume III -Observing Systems, 2018, p.81-112 • Lacombe, M., Bousri, d., Leroy, m., et al. WMO field intercomparison of thermometer screens/shields and humidity measuring instruments. World Meteorological Organization, Instruments and Observing
				Methods, Report, 2011, no 106
				• National Instruments "Engineer's Guide to Accurate Sensor Measurements." (white
				paper)

Table 3 .

 3 Choosing telecommunications technologies.

	Subject	Purpose	Example
	The Internet of Things (IoT) or cyberstructure (including smart cities)	Analyze and compare the characteristics of IoT objects

•

  Minerva, R., Biru, A., et Rotondi, D. Towards a definition of the Internet of Things (IoT).IEEE Internet Initiative, 2015, vol.

			1, no
			1, p. 1-86
			• European Telecommunications Standards Institute works (BESEN, Stanley M. The European telecommunications standards
			institute: A preliminary analysis. Telecommunications policy,
			1990, vol. 14, no 6, p. 521-530.)
			• Morin, E.. Interopérabilité de protocole de communication adaptatifs basse-consommation pour des réseaux de capteurs.
			2018. Thèse de doctorat. // Morin Elodie, Interoperability of
			communication protocole for low consumption sensors networks.
			IoT Standards landscape and future evolutions (European
	Standards and	Compare technologies and	Telecommunications Standards Institute 2016, technical report)
	communications systems	standards

• Liu, J., Zhang, B., et Lv, B.. An intelligent framework of Automatic Weather Station • Murty, R.N., Mainland, G., Rose, I., et al. Citysense: An urbanscale wireless sensor network and testbed. In : 2008 IEEE conference on technologies for homeland security. IEEE, 2008. p. 583-588

Table 4 .

 4 Organizing databases.

	Type	Purpose	Examples
			• The SMM-CD Working Group, 2019: The guidance booklet on the WMO-Wide Stewardship Maturity Matrix for Climate Data. Document
			ID:WMO-SMM-CD-0002.Version: v03r00 20190131.
	Database standards and guidelines (methods)	Help in homogenizing and organizing data and associated metadata	• Guidance for creating WMO Core Profile Metadata in version 1.3, 2015. • Secretariat, W. M. O. I-Purpose and Scope of WIGOS Metadata. • Guide to the WMO Information System, 2017. • Muller, C.L., Chapman, l., Grimmond, c.s.b., et al. Toward a standardized metadata protocol for urban meteorological networks.
			Bulletin of the American Meteorological Society, 2013, vol. 94, no 8, p.
			1161-1185.
	Database (tools) comparisons software	data and metadata software suites to process Help in choosing the best	• Li, Y., et Manoharan, S. A performance comparison of SQL and NoSQL databases. In : 2013 IEEE Pacific Rim Conference on Communications, Computers and Signal Processing (PACRIM). IEEE, 2013. p. 15-19

•

[START_REF] Jatana | A survey and comparison of relational and non-relational database[END_REF]

. A survey and comparison of relational and non-relational database. International Journal of Engineering Research & Technology, 1(6), 1-5.

Table 5 .

 5 Delivering data.Christel, I., Hemment, D., Bojovic, D., et al. Introducing design in the development of effective climate services. ClimateServices, 2018, vol. 9, p. 111-121.

	Type	Purpose

•

Dandin, P., Corre, l., et l'hôte, d.

. Drias, une stratégie de service pour l'adaptation.

Villes et climat, p. 15

• Jourdain, S., Roucaute, e., Dandin, p., et al. Le sauvetage de données climatologiques anciennes à Météo-France: De la conservation des documents à la mise à disposition des données. La Météorologie, 2015

Table 6 .

 6 Climate services transdisciplinarity.

	Type	Purpose	Example
	Guidelines	Provide guidelines for development (e.g., co-construction and components)	• Guidance on Integrated Urban Hydrometeorological, Climate and Environmental Services, 2018 WMO Guideline series. • Daniels, E., bharwani, S., Butterfield, R.. The Tandem framework: a holistic approach to co-designing climate services. Sei Discussion Brief. Stockholm
			Environment Institute, 2019
	Climate services as science services	Provide the conceptualization, goals, and stakes of climate services	• McNie, E. C. (2012). Delivering climate services: Organizational strategies and approaches for producing useful climate-science information. Weather, Climate, and Society, 5(1), 14-26. • Brasseur, G. P., Gallardo, L. (2016). Climate services: Lessons learned and future prospects. Earth's Future, 4(3), 79-89.
			• Bessembinder, J., Terrado, M., Hewitt, C., Garrett, N., Kotova, L., Buonocore, M., Groenland, R. (2019). Need for a common typology of
			climate services. Climate Services, 16, 100135.
	Experience	Present integrated climate
	feedback	services via different
		aspects

•

  Chapman, L., Muller, C.L., Young, D.T., et al. The Birmingham urban climate laboratory: an open meteorological test bed and challenges of the smart city. Bulletin of the American Meteorological Society, 2015, vol. 96, no 9, p. 1545-1560.

•

Christel, I., Hemment, D., Bojovic, D., et

al. Introducing design in the development of effective climate services. Climate Services, 2018, vol. 9, p. 111-121. • Kotova, L., Terrado, M., Krzic, A., Djurdjevic, V., Garrett, N., Stratchan, J., Bessembinder, J. Lessons and practice of co-developing climate services with users, European climate observations, monitoring and services initiative, 2017 • McNie, E. C. (2012). Delivering climate services: Organizational strategies and approaches for producing useful climate-science information. Weather, Climate, and Society, 5(1), 14-26.

Table 7 .

 7 Public and private actors in Toulouse's observation-based urban climate service and their associated participation levels. TM refers to Toulouse Metropolis technical departments.

	Actors	Sector	Participation	Component
	TM: Environment and Energy

-Toulouse University II: Jean Jaurès (Social and Human Sciences) and its Interdisciplinary Laboratory on Solidarity, Societies and Territories (LISST) -Toulouse University III: Paul Sabatier (Medical, Engineering, and Technological Sciences) and its Institute for Research in Computer Science of Toulouse (IRIT)

https://data.toulouse-metropole.fr/pages/accueilv3/, we recommand to use « station » as keyword to find the data.

LAW n° 2014-58, January 27, 2014: "Modernization of territorial public action and affirmation of metropolises"

Acknowledgments

This research is a part of the URCLIM project. URCLIM is a four-year project funded by ERA4CS that started in September 2017. URCLIM received funding from the EU H2020 Research and Innovation Program under Grant Agreement number 690462. Funding was also received from the local authority of the Toulouse Metropole. This research results from the association of the Interdisciplinary Solidarity, Societies, Territories Laboratory (UMR 5193) from Jean Jaurès University (UMR 5193), the Toulouse Metropole (Environment and Energy Department), and CNRM (National Center for Meteorological Research, UMR 3589). We thank Martha Evonuk, PhD, from Evonuk Scientific Editing (http://evonukscientificediting.com) for editing a draft of this manuscript.