Zouari Sonda
email: sonda.zouari91@gmail.com

Boussetta Soumaya

Siani Giuseppe

Tisnerat-Laborde Nadine

Thil François

Kallel Abdelaziz

Michel Elisabeth

Kallel Nejib

Sonda Zouari

Mediterranean faunal evolution and biochronological events during the last 24 kyr

Keywords: Mediterranean Sea, planktonic foraminifera, SST, LGM, bio-event, AMS14C

We generated high-resolution biochronological records in the Mediterranean Sea covering the period extending to the Late-glacial. The present study is based on micropaleontological, sea-surface temperature (SST) and oxygen isotopic analyses performed along three well-dated deep-sea cores: REC13-53, KET80-19 and MD84-641 recovered in the Siculo-Tunisian Strait, Tyrrhenian Sea and Levantine Basin, respectively. The quantitative distributional patterns of planktic foraminifera permitted to identify seven biozones based on the apparition and/or disappearance of the main specific taxa or by their noticeable abundance peaks. Abundance records display that major changes in planktic foraminiferal assemblages have a similar pattern mainly in central and western basins. In particular, four recognized bio-events can be used to establish or to improve the chronology of Mediterranean deep-sea cores. The comparison of the SST estimates and foraminiferal records with those of NGRIP ice-core shows a similarity between the Greenland climate and the Mediterranean hydrology. This indicates that the main climate changes recorded in the North Atlantic are globally in phase with those observed in the Mediterranean region.

Highlights

► We present a high-resolution biochronological records in the Mediterranean Sea. ► Seven biozones are identified basing on the distributional patterns of planktic foraminifera. ► Four bio-events were recognized, and they should improve the chronology of Mediterranean cores. ► A similarity between the global climate and the Mediterranean hydrology is observed.

1.

Introduction

Since the Mediterranean Sea is located at the interface between the European temperate westerlies and the African subtropical zone, it's considered of great interest to yield information on paleoclimatic and palaeoceanographic changes acting at different time scales during the Late Quaternary [START_REF] Cacho | Dansgaard-Oeschger and Heinrich event imprints in Alboran Sea paleotemperatures[END_REF][START_REF] Cacho | Evidence for enhanced Mediterranean thermohaline circulation during rapid climatic coolings[END_REF][START_REF] Sierro | Impact of iceberg melting on Mediterranean thermohaline circulation during Heinrich events[END_REF][START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF], 2019;[START_REF] Melki | Abrupt climate change, sea surface salinity and paleoproductivity in the western Mediterranean Sea (Gulf of Lion) during the last 28 kyr. Palaeogeogr. J o u r n a l P r e -p r o o f Journal Pre-proof Palaeoclimatol[END_REF][START_REF] Sprovieri | Centennial-to millennial-scale climate oscillations in the Central-Eastern Mediterranean Sea between 20,000 and 70,000 years ago: Evidence from a high-resolution geochemical and micropaleontological record[END_REF]Gàmiz et al., 2014 and references therein). The present-day Mediterranean climate is characterized by a strong seasonality of rainfall and temperature with mild and wet winters and warm and dry summers [START_REF] Quézel | Ecologie et biogéographie des forêts du bassin méditerranéen[END_REF][START_REF] Lionello | The Mediterranean Climate: An overview of the main characteristics and issues[END_REF][START_REF] Bout-Roumazeilles | Tracking atmospheric and riverine terrigenous supplies variability during the last glacial and the Holocene in central Mediterranean[END_REF].The northern Mediterranean regions are characterized by mean annual SSTs lower than those presented in the other sub-basins. The lowest values are recorded in the Gulf of Lions (17.3°C), the Northern Adriatic Sea (17.1°C) and the Siculo-Tunisian Strait (19°C) [START_REF] Locarnini | Temperature. Mishonov, A[END_REF] whereas the Levantine Basin constitutes the warmest region with mean annual SSTs of about 21.6°C.

Several studies based on different marine proxies (stable isotope, calcareous nannoplankton, benthic and planktonic foraminifera, dinoflagellates) have been used in the reconstruction of palaeoceanographic changes in the Mediterranean Sea during the Late Quaternary providing useful insights to define biological events or biozones [START_REF] Pujol | Palaeoceanography of the last deglaciation in the Alboran Sea (western Mediterranean). Stable isotopes and planktonic foraminiferal records[END_REF][START_REF] Capotondi | The last deglaciation in the South Adriatic Sea: J o u r n a l P r e -p r o o f Journal Pre-proof Biostratigraphy and paleoceanography[END_REF][START_REF] Capotondi | Foraminiferal ecozones, a high resolution proxy for the late Quaternary biochronology in the central Mediterranean Sea[END_REF][START_REF] Asioli | Submillennial scale climatic oscillations in the central adriatic during the lateglacial: Palaeoceanographic implications[END_REF][START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] Stable oxygen isotopes ( 18 O) were measured on planktonic foraminifera at the Laboratoire des Sciences du Climat et de l'Environnement (LSCE) on a GV Isoprime mass spectrometer. Isotopic measurements were obtained for REC13-53 on the planktonic foraminifera G. bulloides (250-315 μm fraction), with a sampling resolution every 8 cm along the 5 meters of the core and corresponding to 65 samples. About 4 to 30 shells were sampled for each analysis, cleaned using methanol and ultrasonic bath, and heated at 380 °C during 45 min. The measurements are reported versus the Vienna Pee Dee Belemnite standard (VPDB) with NSB19 standard at  18 O = -2.20‰, with a mean external reproducibility (1) of carbonate standards of ± 0.05‰.

Radiocarbon analyses

Thirteen radiocarbon dating were performed on core REC13-53 on monospecific planktonic foraminifera shells of G. bulloides, G. ruber and N. incompta in the size fraction >150m. Samples were processed according to the procedure described by [START_REF] Tisnérat-Laborde | Development of a Semi-Automated System for Routine Preparation of Carbonate Samples[END_REF] slightly modified for samples of mass less than 2 mg. Samples were directly introduced in the main branch of Y glass reactor and are leached with only 100 µL of HNO 3 at 10 -2 M. 10 drops of pure H 3 PO 4 were added in the second branch of tube. Then, the reactor is rapidly connected to semi-automated carbonate lines. Samples were transformed by hydrolyse into CO 2 and the released CO 2 is dried, cryogenically transferred into µtubes (3 x 7 mm) and then µtubes were sealed. CO 2 samples (from 70 to 160 µgC) were measured with the gas ion source at ECHoMICADAS at the LSCE (Gif-Sur-Yvette, France) using coupling of cracker system to the gas handling system [START_REF] Wacker | A versatile gas interface for routine radiocarbon analysis with a gas ion source[END_REF][START_REF] Tisnérat-Laborde | ECHoMICADAS: A new compact AMS system to measuring 14C for environment, climate and human sciences[END_REF]. 14 C results are reported in conventional age BP according to the convention of [START_REF] Stuiver | Rapid Reconstruction of Paleoenvironmental Features Using a New Multiplatform Program Short Note Rapid reconstruction of paleoenvironmental features using a new multiplatform program[END_REF], normalized to the base of δ 13 C of -25.0‰ relative to the Pee Dee Belemnite (PDB) international standard, and corrected by the age of the background subtraction. One date was measured on UMS-ARTEMIS (Pelletron 3 MV) AMS facilities (CNRS-CEA Saclay, France). The age models for the cores were derived from the calibrated planktonic ages by applying a variable sea-surface reservoir 14 C correction [START_REF] Siani | Radiocarbon reservoir ages in the Mediterranean Sea and Black Sea[END_REF][START_REF] Siani | Mediterranean sea surface radiocarbon reservoir age changes since the last glacial maximum[END_REF] and using INTCAL20 [START_REF] Reimer | THE INTCAL20 NORTHERN HEMISPHERE RADIOCARBON AGE CALIBRATION CURVE (0-55 CAL kBP)[END_REF] calibration curve in the Oxcal 4.4 software [START_REF] Bronk-Ramsey | Dealing with Outliers and Offsets in Radiocarbon Dating[END_REF].

J o u r n a l P r e -p r o o f

Planktonic foraminifera analyses

For micropaleontological analyses, samples were dried at 50°C, washed through mesh diameters of 150 μm using distilled water. Quantitative and qualitative analyses on planktonic foraminifera have been performed on the fraction > 150 μm. This fraction was subsequently divided by a microsplitter into aliquots each containing at least 300 specimens of planktonic foraminifera. All the specimens present in the sub-samples were then counted and identified according to the taxonomic concept adopted by [START_REF] Pujol | Distribution patterns of live planktic foraminifers as related to regional hydrography and productive systems of the Mediterranean Sea[END_REF] and [START_REF] Schiebel | Planktic Foraminifers in the Modern Ocean[END_REF]. On the basis of this classification, more than 94% of our planktonic foraminifera fauna is dominated by the following species: Globigerina bulloides; the two Neogloboquadrina species N. pachyderma and N. incompta which are referred to left and right coiling forms, respectively; Globorotalia truncatulinoides right (r.c) and left (l.c) coiling species; Globigerinoides ruber (s.l) including both varieties (pink and white);

Orbulina universa; Globorotalia scitula; Globorotalia inflata; Globigerinita glutinata; Turborotalia quinqueloba; Globigerinella calida; Globigerinoides conglobatus; Globigerinoides sacculifer (s.l), including Globigerinoides trilobus and Globigerinoides. sacculifer sensu strictu (s.s).

Then, all the results of planktonic foraminifera counting are presented in terms of their relative abundances (percentages of the total number).

Modern Analogue Technique (MAT)

We derived Annual SSTs for the three Mediterranean cores by the use of the Modern Analog Technique (MAT; [START_REF] Hutson | The Agulhas current during the Late Pleistocene: Analysis of modern faunal analogs[END_REF][START_REF] Prell | Stability of low-latitude sea-surface temperatures: an evaluation of the CLIMAP reconstruction with emphasis on the positive SST anomalies[END_REF] through planktonic foraminifera census counts using the Paleoanalog program (Therón et al., 2004). For this study, the MAT statistical temperature reconstructions are based on the recently developed ForCenS foraminiferal database (Siccha and Kucera, 2017). This database consists of synthesis of planktonic foraminifera assemblage counts from surface sediment samples which comprise 4.205 singular counts from unique sites worldwide. The data set includes the compilations of numerous data bases: CLIMAP (CLIMAP Project members, 2009), the Brown University Foraminiferal Database (BUFD) (Prell et al., 1999), the ATL947 database (Pflaumann et al., 2003) and MARGO (Kucera et al., 2005;Hayes et al., 2005). The individual datasets of Hüls et al. (1999), Mohtadi et al. (Mohtadi et al., 2005;Mohtadi, 2010), Salgueiro et al. (2008), Siccha et al. (2017) and [START_REF] Munz | ECHo2533 ECHo2535 ECHo2537 ECHo2199 ECHo2539 ECHo3276 ECHo[END_REF] are also considered into the database. However, in J o u r n a l P r e -p r o o f Journal Pre-proof the present study we have considered only the Mediterranean Sea core tops (125 samples) and 632 core tops from the North Atlantic Ocean. We have chosen this dataset as it is the most extensive and most recent compilation to date. It contains more samples in the Atlantic Ocean and has undergone to the process of transparent Quality control. In fact, samples of insufficient quality were flagged and excluded from this database (Siccha and Kucera, 2017). We used the modern analogue technique [START_REF] Hutson | The Agulhas current during the Late Pleistocene: Analysis of modern faunal analogs[END_REF][START_REF] Prell | Stability of low-latitude sea-surface temperatures: an evaluation of the CLIMAP reconstruction with emphasis on the positive SST anomalies[END_REF]Kallel et al., 1997a) to compare fossil planktonic foraminiferal samples to this data base and to identify, for each fossil assemblage, the 10 best modern analogues. The modern analogue approach uses dissimilarity coefficients to measure the mean degree of dissimilarity between each fossil samples and the modern samples of the reference data base. Among the different kinds of dissimilarity coefficients, it has been demonstrated that the "squared chord distances" type, which we use in the present study, gives the best temperature estimates with the smallest standard deviations between the observed and estimated climatic parameters [START_REF] Prell | Stability of low-latitude sea-surface temperatures: an evaluation of the CLIMAP reconstruction with emphasis on the positive SST anomalies[END_REF] and has the advantage of giving importance even to low percentage planktonic species. For each fossil association of planktonic foraminifera, the SST at which it developed is given by the dissimilarity weighted temperatures of the 10 best modern analogues selected by the statistical analysis. According to [START_REF] Prell | Stability of low-latitude sea-surface temperatures: an evaluation of the CLIMAP reconstruction with emphasis on the positive SST anomalies[END_REF], when the dissimilarity coefficient is lower than 0.21, the estimated SSTs are considered as reliable. Annual SSTs are considered in the present study.

Finally, for each sample of the reference database, the temperatures were extracted from the World Ocean Atlas (WOA, 1998) at a depth of 0 m.

Results and discussion

Age model

The age model of core REC13-53 is based on oxygen isotope stratigraphy and by 13 AMS 14 C measurements carried out on monospecific planktonic foraminifera all along the core (Fig. 2). The conventional radiocarbon ages were converted into calendar age using INTCAL20 [START_REF] Reimer | THE INTCAL20 NORTHERN HEMISPHERE RADIOCARBON AGE CALIBRATION CURVE (0-55 CAL kBP)[END_REF] and the 14 C calibration software Oxcal 4.4 (Bronk-Ramsey, 2009;[START_REF] Bronk-Ramsey | Recent and Planned Developments of the Program OxCal[END_REF]. The calibration integrates a marine reservoir correction (reservoir 14 C age) according to [START_REF] Siani | Radiocarbon reservoir ages in the Mediterranean Sea and Black Sea[END_REF][START_REF] Siani | Mediterranean sea surface radiocarbon reservoir age changes since the last glacial maximum[END_REF]. The calibrated age ranges are reported in calendar years BP and refer to an uncertainty at 2σ (Tab 2). The mean calculated sedimentation rate is estimated at about 22 cm/kyr from the Late Glacial to the Holocene.

As for the two other cores, KET80-19 and the MD84-641 presented above, their age model have already been published by Kallel et al. (1997b[START_REF] Kallel | Mediterranean Sea palaeohydrology and pluvial periods during the Late Quaternary[END_REF]; [START_REF] Fontugne | Late Pleistocene variability of the carbon isotopic composition of organic matter in the eastern Mediterranean: Monitor of changes in carbon sources and atmospheric CO2 concentrations[END_REF] and J o u r n a l P r e -p r o o f [START_REF] Melki | The nature of transitions from dry to wet condition during sapropel events in the Eastern Mediterranean Sea Palaeogeogr[END_REF], respectively. In this study, we have refined the previous age models by recalibrating the published radiocarbon ages using INTCAL20 [START_REF] Reimer | THE INTCAL20 NORTHERN HEMISPHERE RADIOCARBON AGE CALIBRATION CURVE (0-55 CAL kBP)[END_REF] (Tab 2). bulloides (Fig. 2, 3) exhibiting a pattern similar to those observed in nearby deep-sea cores [START_REF] Essallami | Hydrological changes in the Mediterranean Sea over the last 30,000 years[END_REF]. The  18 O record for core REC13-53 displays a glacial to Holocene  18 O difference of ~ 3.2 ‰. The heaviest  18 O values (up to ~3.5 ‰) are found from ~23 to ~18 kyr followed by a two-step decreasing deglacial trend reaching 0.7 ‰ at ~8.6 kyr interrupted by centennial to millennial  18 O variability (~2.8 to 2.5 ‰) from ~16 to 12 kyr (Fig. 3). From ~12 to 8.5 kyr, the  18 O values are marked by a decreasing trend (~1.7 ‰) followed by a short-term variability until ~ 5 kyr. Afterwards, steady  18 O values at ~ 1 ‰ are recorded until present-day.

Mediterranean

Sea-surface temperature (SSTs)

Over the last 24 kyr, Siculo-Tunisian Annual SST estimates by modern analogue technique (MAT) display large amplitude temperature fluctuations, indicating a succession of cold and warm periods (Fig. 3). Annual SST estimates range from ~9°C during the glacial period (GS-2) to ~19°C for the Holocene. The lowest values are recorded between 19 kyr to 15 kyr and 12.9 kyr to 11.6 kyr since the transition from the Late Glacial (GS-2b) and the Oldest Dryas/Heinrich Event (HE) 1 (GS-2a) and Younger Dryas (GS-1) respectively, whereas the warmest are observed during the Bolling/Allerod (GI-1) (14.8 kyr to 12.9 kyr) and the Holocene period. SST estimates present good dissimilarity coefficients all along the record generally < 0.21 with an average value of 0.13 (varying between 0.05 and 0.24). The mean standard deviation of SST estimates is ~0.69°C during the Holocene and ~1.38°C since the late glacial period (Fig. 3). Interestingly, the comparison between SST estimates of core REC13-53 with δ 18 O of NGRIP ice core reveal that the main climatic phases observed in the North Atlantic region over the last 24 kyr match well those recorded in the Siculo-Tunisian Strait (Fig. 3).Therefore, in the following sections we relate our planktic foraminiferal record J o u r n a l P r e -p r o o f to the NGRIP event stratigraphic framework [START_REF] Lowe | Synchronisation of palaeoenvironmental events in the North Atlantic region during the Last Termination: a revised protocol recommended by the INTIMATE group[END_REF][START_REF] Blockley | Synchronisation of palaeoenvironmental records over the last 60,000 years, and an J o u r n a l P r e -p r o o f Journal Pre-proof extended INTIMATE 1 event stratigraphy to 48,000 b2k[END_REF][START_REF] Rasmussen | A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three synchronized Greenland ice-core records: Refining and extending the INTIMATE event stratigraphy[END_REF] in order to better identify the relationship between North Atlantic to regional climatic changes and the response of microfaunal assemblages in the Mediterranean basin over the last 24 kyr.

Planktic foraminiferal record over the last 24 kyr in the Mediterranean Sea

The study of the assemblage variations of planktonic foraminifera fauna along the Mediterranean cores permits to define biological events or biozones. These biozones are defined, on the basis of temporary local appearance and/or disappearance of some specific taxa of planktonic foraminifera, or by their noticeable abundance peaks. In this biochronological framework, we will present and discuss our results in comparison with previous studies performed in the main basins of the Mediterranean Sea [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF][START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF][START_REF] Principato | Late Pleistocene-Holocene planktonic assemblages in three box-cores from the Mediterranean Ridge area (westsouthwest of Crete): Palaeoecological and palaeoceanographic reconstruction of sapropel S1 interval[END_REF][START_REF] Geraga | Short-term climate changes in the southern Aegean Sea over the last 48,000 years[END_REF][START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF][START_REF] Triantaphyllou | Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages[END_REF].Therefore, according to the planktic foraminiferal distributional pattern, we reconstruct the biochronological events of the three deep-sea sediment cores. Here, we identify seven biozones in cores REC13-53 and KET 80-19 and only six biozones in MD84-641 during the last ~24 kyr (Fig. 4) that are summarized here below.

Biozone 7

The biozone 7 (Fig. 4,5) represents the time interval corresponding to the Late glacial period (GS2-b, c) including the last glacial maximum (LGM). It has been identified in the Siculo- 5a). The planktic foraminiferal fauna presents a high diversity displayed by a mixture between cold and warm species dominated by N. incompta, (40%), T. quinqueloba (11%), G. bulloides (21%), G. glutinata (13%), G. scitula (5%) with a peak of about 11% at 18.1±0.8 kyr, and by G. ruber (10%). A sudden decrease of the subtropical species G. ruber and a coeval peak of the subpolar species T. quinqueloba (28%) at 18.3±0.79, mark the upper boundary of this biozone. The two relevant peaks of G. scitula and J o u r n a l P r e -p r o o f Journal Pre-proof T. quinqueloba simultaneous to the drop of G. ruber were also observed in the core KET80-19, at 18.2±0.58 kyr. The planktic foraminiferal assemblage show a good similarity with that from REC13-53 core whilst SSTs estimates indicate different features with a mean value of 11°C between 23.5-22 kyr and an increase of 3°C until 18 kyr (Fig. 4b,5c).

The particularity of these two faunal assemblages is the simultaneous presence of both the subtropical species G. ruber (up to 13% for KET80-19 and 10% for REC13-53) and the subpolar species N. incompta (32% for KET80-19 and 40% for REC13-53) as well as the relative abundance peak of T. quinqueloba at 18.2 kyr that are also observed in the nearby core GNS84-C106 collected at the same latitude in the Gulf of Salerno but at lesser depth on the continental margin [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]. However, the foraminiferal assemblage is slightly different in core GNS84-C106 marked by higher abundances of the subtropical species G. ruber (30%) and a lower percentage of the subpolar one N. incompta (18%). The low frequency of the latter species was probably due to the low bathymetry of the recovered core at water depth of 293 m off the Sele Plain in the Gulf of Salerno. This location probably prevents the occurrence of the deep dwelling species such as N. incompta especially during the late glacial sea-level lowering whereas the abundance of the warm species G. ruber is rather related to the adopted mesh sieve. Interestingly, [START_REF] Buccheri | A high resolution record of the last deglaciation in the southern Tyrrhenian sea: Environmental and climatic evolution[END_REF] analyzed the same core (GNS84-C106) with lower mesh sieve (>106 µm) and found different percentages (10% for G. ruber and 10% of N. incompta). In both studies, the percentage of N. incompta is lower than that observed in our core, reflecting the shallower depth of the core GNS84-C106 as indicated above. However, the highest percentage of the shallow dwelling taxa G. ruber observed in Di [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] is rather related to the different mesh sieve used in that study (>150 µm) leading to a larger loss of the small size surface dwelling taxa T. quinqueloba (60 to 70% in [START_REF] Buccheri | A high resolution record of the last deglaciation in the southern Tyrrhenian sea: Environmental and climatic evolution[END_REF] compared to 5-10% in Di [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]).

In the Levantine basin the assemblage is dominated by the subtropical species G. ruber (up to 68%) and the subpolar species N. incompta (21%) making it significantly different from that observed in the two other core sites (Fig. 4c).

Based on the stratigraphic subdivision, the identified biozone 7 from our three cores is correlated with the two sub-ecozones 8Fa (GS-2c) and 8Fb (GS-2b) from the ODP hole 963 D [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] as well as the biozone 7 from core79-22 located in the Cefalù basin (southern Tyrrhenian Sea; [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF]. It also corresponds to the two compositional-J o u r n a l P r e -p r o o f zones F5c and F5b of the core GNS84-C106 located in the Gulf of Salerno [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] (Fig. 6).

Biozone 6

Biozone 6 corresponds to the first step of the deglaciation as indicated by progressive lighter  18 O values dated between 18.3±0.79 and 14.8±0.45 kyr in the Siculo-Tunisian Strait (Fig. 3), from 18.2±0.58 to 14.5±0.55 kyr in the Tyrrhenian Sea and between 19±0.64 and 15±0.48 kyr in the Levantine basin respectively. The onset of this biozone is marked by the decline of the subtropical species G. ruber in REC13-53 and KET80-19 cores while those from MD84-641 slightly decrease without reaching values less than 60% (Fig. 4a,4b). The planktic foraminiferal microfauna in core REC13-53 is generally characterized by the predominance of the subpolar species N. incompta (38%), and subordinately G. bulloides (23%), T. quinqueloba (7%), and G. scitula (4%). Interestingly, the species G. glutinata is also highly representative of this interval with a mean percentage of about 23% whereas, the subtropical species G. ruber is almost absent. The first postglacial occurrence of the two species G. truncatulinoides r.c and G. inflata is observed at 14.6±0.4 and 15.3±0.6 kyr, respectively. These two bio-events occurred as well in core KET80-19 at 14.3±0.45 and 15.1±0.78 kyr, respectively. According to the cold Annual SST estimates (9.5°C in REC13-53 and KET80-19); biozone 6 corresponds to the cold GS-2a event recorded in NGRIP ice core (Fig. 5a,5c). This cold episode was identified between 17 kyr and 14.7 kyr in the Gulf of Salerno as indicated by a SST decrease of ~8°C [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]. In addition, this cold event was also recorded in the Alboran Sea by alkenone SST reconstructions and attributed to the Heinrich event H1 [START_REF] Martrat | Similarities and dissimilarities between the last two deglaciations and interglaciations in the North Atlantic region[END_REF][START_REF] Hodell | Anatomy of Heinrich Layer 1 and its role in the last deglaciation[END_REF].

In the Levantine basin, the microfauna assemblage is rather dominated by the subtropical species G. ruber (62%) and by the subpolar species N. incompta (26%). However, due to the high dissimilarity coefficient (>0.21), Annual SST estimates during this time-interval have to be considered with caution (Fig. 5e,5f).

Biozone 6 is tentatively correlated with the sub-biozone 8Fc (GS-2a) of [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] in the Siculo-Tunisian Strait (Fig. 6), despite the small discrepancy related to the quantitative distribution of G. glutinata, more abundant (25%) in our record compared to the nearby ODP site 963 D. It also corresponds to the two sub-zone 6b and 6a of [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF] to the interstadial Bølling/Allerød/GI-1(Fig. 5a,5c). However, the aforementioned warming is less pronounced in the Levantine Basin as indicated by the Annual SSTs record (~2°C) (Fig. 5e). The onset of biozone 5 in the two cores REC13-53 and KET80-19 is defined by the reentry of the warm species G. ruber and the occurrence of G. inflata as well as of G. truncatulinoides r.c and O. universa even with low percentages (Fig. 4a,4b). In addition, in the Siculo-Tunisian Strait, moderate percentages of subpolar and temperate species N. incompta and G. bulloides (20% and 24%, respectively) marked this biozone even though the latter species is more abundant in the Tyrrhenian Sea reaching 41%. The microfaunal assemblage is also characterized by the noticeable decrease of the colder species G. scitula and T. quinqueloba as well as by the cosmopolitan species G. glutinata. A decline of G.

scitula is recorded at 14.8±0.45 kyr in core REC13-53 and at 14.3±0.32 kyr in core KET80-19 respectively. This pattern was also observed in the southern Tyrrhenian Sea by [START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF] and in the Gulf of Salerno by [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]. Two colder SST spells marked by the coeval decrease of G. ruber and the rise of N. incompta, are observed in the Siculo-Tunisian Strait at ~14.4±0.35 and ~13.4±0.40 kyr. These short-term events can be attributed, taking into account the age model uncertainties at 2, to the GI-1d and GI-1b events respectively, described in Greenland ice cores and according to the extended INTIMATE stratigraphy [START_REF] Rasmussen | A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three synchronized Greenland ice-core records: Refining and extending the INTIMATE event stratigraphy[END_REF]. The two falls of G. ruber were already reported in the nearby ODP hole 963D [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] as well as in the central and southern Adriatic and Tyrrhenian seas [START_REF] Asioli | Short-term climate changes during the Last Glacial -Holocene transition : comparison between Mediterranean records and the GRIP event stratigraphy[END_REF][START_REF] Asioli | Submillennial scale climatic oscillations in the central adriatic during the lateglacial: Palaeoceanographic implications[END_REF][START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF] and equally related to the GI-1d and GI-1b events.

In the Levantine basin, despite not having occurred significant changes in the faunal assemblage, the onset of the biozone 5 is rather marked by the first occurrence of the species J o u r n a l P r e -p r o o f G. truncatulinoides r.c at 14.5±0.43 kyr and by the increase in abundance of G. inflata. As mentioned above, Annual SST estimates indicate a slight increase of about 2°C (Fig. 4c,5e).

Through these results, we correlate biozone 5 with ecozone 7F (GI-1) of ODP site 963 D [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] also characterized by a lower percentage of T. quinqueloba and a higher abundance of N. incompta, G. ruber and G. inflata. This biozone is also correlated with the biozone 5 of [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF]) (Fig. 6) marked by a greater abundance of G. ruber and a lower abundance of G. glutinata and displaying two consecutive peaks of G. inflata and with the lower part of the compositional-zone F4 proposed by [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF].

Moreover, based on the inferred age models, biozone 5 also corresponds to biozone 5 of the core C69 in the southern Aegean Sea [START_REF] Geraga | Short-term climate changes in the southern Aegean Sea over the last 48,000 years[END_REF] and to ecozone APFE-9 (14-13.1 kyr) of the core NS-14 in the south-eastern Aegean Sea [START_REF] Triantaphyllou | Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages[END_REF] (Fig. 6).

Biozone 4

Biozone 4 has been identified in the Siculo-Tunisian Strait between 12.9±0.37 and 11.6±0.31 kyr, in the Tyrrhenian Sea from 12.9±0.91 to 11.6±0.33 kyr and in the Levantine basin between 13.5±0.35 and 11.6±0.43 kyr. It corresponds to the Younger Dryas/GS-1 cold event when Annual SST estimates decrease by about 7.5°C and 9.5°C in the REC13-53 and KET80-19 respectively, marking the return to full glacial conditions (Fig. 5a,5c). The abrupt decrease of the subtropical species G. ruber in the three cores permits to define the lower boundary of this biozone. The microfaunal assemblage from core REC13-53 characterizing this interval is marked by the increase in the abundance of cold species N. incompta (38%) with a relevant peak (up to 55%) at 12.8 kyr and of T. quinqueloba (12%), accompanied by the presence of G. glutinata (12%) and G. bulloides (21%). The assemblage is also characterized by the near disappearance of G. ruber even though a slight increase is observed at ~12.3 kyr. While showing a large resemblance with core REC13-53, the planktic assemblage from core KET80-19 slightly differs in the abundance of the two species N. incompta and G. glutinata reaching 22 and 35%, respectively. A similar planktic foraminiferal assemblage to core KET80-19 is observed in the nearby core GNS84-C106 [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]. However, a marked difference concerns the significant presence of the subtropical species G. ruber (10%), which is not present in our record. As indicated above, the highest frequency of the shallow dwelling taxa G. ruber observed in Di [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] is related to the different J o u r n a l P r e -p r o o f mesh sieve used in that study (>150 µm) leaded to a large loss of the surface dwelling taxa T.

quinqueloba.

The YD cold event recorded in the Tyrrhenian Sea is also observed in other Mediterranean basins with April-May SST estimates decrease by about 6.5°C in the Siculo-Tunisian Strait [START_REF] Essallami | Hydrological changes in the Mediterranean Sea over the last 30,000 years[END_REF], 4°C in the South Adriatic Sea [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF] and 4.5°C in the Gulf of Lions [START_REF] Melki | Abrupt climate change, sea surface salinity and paleoproductivity in the western Mediterranean Sea (Gulf of Lion) during the last 28 kyr. Palaeogeogr. J o u r n a l P r e -p r o o f Journal Pre-proof Palaeoclimatol[END_REF]. Our SST estimates in core MD84-641 also show a slight decrease of 2.5°C during the same time interval (Fig. 5e). This cooling is accompanied by a slight decrease of the warm species G. ruber, together with the sudden drop of the subpolar species N. incompta. However, a rise in G. bulloides is observed from 13.5 kyr with a peak (26%) just at the lower zonal boundary of this biozone. The planktic foraminiferal assemblage is mainly represented by two species of G. ruber (65%) and G. bulloides (17%) and punctuated by the disappearance of G. scitula.

Biozone 4 is correlated with the ecozone 6F (GS-1) of [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] (Fig. 6) although G. ruber and G. glutinata are almost absent and T. quinqueloba is more abundant. These discrepancies could be explained by the difference between the mesh-size of the sieve adopted in our study (150 µm) and the one (125µm) used by [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF]. In fact, larger sieve meshes lead to a major loss of small sized species such as T. quinqueloba. Moreover, this biozone also corresponds to the biozone 4 of [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF] characterized by a drop in the abundance of G. ruber and G. inflata and an increase of G. glutinata with a peak at 12.3 kyr, and with the upper part of the zone F4 of Di [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]. On the other hand, the biozone 5/4 boundary of MD84-641 is correlated with the biozone 5/4 boundary of [START_REF] Geraga | Short-term climate changes in the southern Aegean Sea over the last 48,000 years[END_REF] in the southern Aegean Sea and with ecozone APFE-9/APFE-8 boundary of core NS-14 in the south-eastern Aegean Sea as indicated by an important increase in G.

bulloides [START_REF] Triantaphyllou | Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages[END_REF] (Fig. 6).

Biozone 3

Biozone 3 marks the onset of the Holocene as characterized by a consistent lowering of the  18 O values (Fig. 3) covering the time interval between 11.6±0.31 to 9.5±0.14 kyr in the Siculo-Tunisian Strait, 11.6±0.33 to 9.5±0.24 kyr in the Tyrrhenian Sea and from 11.6±0.43 to 9.5±0.29 kyr in the Levantine basin respectively. Annual SST estimates increased again and reached higher values with a large amplitude change of about 7.5 and 8.5°C indicating the end of glacial conditions in the two studied cores REC13-53 and KET80-19 respectively (Fig. 5a,5c). In accordance with chronology and the climatic feature, this interval corresponds to J o u r n a l P r e -p r o o f the upper part of the Early Holocene (11.6 -8.2 kyr after [START_REF] Walker | Formal ratification of the subdivision of the Holocene Series/ Epoch (Quaternary J o u r n a l P r e -p r o o f Journal Pre-proof System/Period): two new Global Boundary Stratotype Sections and Points (GSSPs) and three new stages/ subseries[END_REF]. In fact, the reoccurrence of the warmer species G. ruber, associated with the marked decrease of the subpolar species N. incompta, define the onset of this biozone at about 11.6 kyr (Fig. 4a,4b).

Biozone 3 is characterized by the predominance of G. ruber (38%), G. bulloides (24%), G. inflata (18%), and G. truncatulinoides l.c (8%) and by a sudden drop of subpolar species N. incompta and by the re-entry of O. universa, G. calida, and G. sacculifer group from 11±0.34 kyr. Interestingly, a significant rise in G. inflata is observed in both cores between 11 to 9.5 kyr and culminating with a peak (38%) at 10.3 kyr. A similar increase in G. inflata was previously recognized in the northern Tyrrhenian Sea [START_REF] Carboni | Late Quaternary paleoclimatic and paleoenviromental changes in the Tyrrhenian Sea[END_REF], in the Gulf of Salerno [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF], in the south Tyrrhenian Sea [START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF] as well as in the south Adriatic sea [START_REF] Rohling | 200 Year interruption of Holocene sapropel formation in the Adriatic Sea[END_REF][START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF], and from several eastern Mediterranean cores [START_REF] Principato | Late Pleistocene-Holocene planktonic assemblages in three box-cores from the Mediterranean Ridge area (westsouthwest of Crete): Palaeoecological and palaeoceanographic reconstruction of sapropel S1 interval[END_REF][START_REF] Geraga | Short-term climate changes in the southern Aegean Sea over the last 48,000 years[END_REF], suggesting a strong vertical mixing of the water column and cool environments with relatively eutrophic waters.

In the Levantine basin, the onset of this biozone is especially characterized by the first entry of the subtropical species G. sacculifer group (up to 27%) and G. calida (4%), and the synchronous disappearance of N. incompta (Fig. 4c). Moreover, the last occurrence of G. truncatulinoides species with low percentage (4%) is also observed at 10.6 kyr. This biozone is also marked by the strongest presence of G. ruber reaching 70% of the total assemblage. Biozone 3 is correlated with the ecozone 5F of [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF], displaying the two coeval major peaks of G. ruber at ~11.2 and ~9.7 kyr and the peak of G. inflata at ~10.6 kyr, respectively. It also corresponds to the biozone 3 of [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF]

Biozone 2

Biozone 2 is identified between 9.5±0.14 and 5.6±0.34 kyr in the Siculo-Tunisian Strait, from 9.5±0.24 to 5.6±0.21 kyr in the Tyrrhenian Sea and between 9.5±0.29 to 4.5±0.27 kyr in the Levantine basin. This biozone is related to the interval between the end of the Early Holocene and the middle Holocene including the sapropel S1 deposition in the Eastern Mediterranean Sea [START_REF] De Lange | Synchronous basin-wide formation and redox-controlled preservation of a Mediterranean sapropel[END_REF]. In our records, the sapropel S1 was only observed in core MD84-641 and deposited between 9.3 and 6.7 kyr during the most recent period of stagnation in the J o u r n a l P r e -p r o o f Eastern Mediterranean [START_REF] Rossignol-Strick | After the deluge: Mediterranean stagnation and sapropel formation[END_REF][START_REF] Rohling | Review and new aspects concerning the formation of eastern Mediterranean sapropels[END_REF][START_REF] Fontugne | Paleoenvironment, sapropel chronology and Nile river discharge during the last 20,000 years as indicated by deep-sea sediment records in the eastern Mediterranean[END_REF]Kallel et al., 1997a;[START_REF] Mercone | Duration of S1, the most recent sapropel in the eastern Mediterranean Sea, as indicated by accelerator mass spectrometry radiocarbon and geochemical evidence[END_REF].

A marked increase of the subpolar species N. incompta (25%) marks the base of this biozone in core REC13-53, even though SST estimates indicate almost constant values (19.5°C) throughout the entire interval. The dominant species are represented by G. inflata (19%), G. ruber (33%) and G. bulloides (20%). The warm species O. universa, G. calida, G. sacculifer group, are also present within this interval even though with low percentages. The assemblage characterizing this biozone is slightly different to that observed in the Tyrrhenian Sea core KET80-19 where the abundance of the species G. inflata is of 15%, 22% for G. ruber and 11% for G. bulloides. However, the subpolar planktic foraminifera N. incompta (45%) is more abundant, exhibiting an outstanding peak of 66% at 6.8±0.15 kyr, that could explain the SST decrease by about 3.5°C in this core. The planktic faunal assemblage characterizing this biozone is slightly different from that recorded in the continental shelf (i.e. core GNS84-C106; Di [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF], which is characterized by lower abundances of the subpolar deep-dwelling species N. incompta (13%) and higher percentages of the subtropical species G. ruber (35%). These differences are likely related to the low bathymetry of the GNS84-C106 core. The decrease in SST (between 9.5 and 5.6 kyr) is also observed in the southern Tyrrhenian Sea [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF] but less pronounced than that recorded in core KET80-19, in the Gulf of Lion [START_REF] Melki | Abrupt climate change, sea surface salinity and paleoproductivity in the western Mediterranean Sea (Gulf of Lion) during the last 28 kyr. Palaeogeogr. J o u r n a l P r e -p r o o f Journal Pre-proof Palaeoclimatol[END_REF] and in South Adriatic Sea [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF].

However, this cooling period is not recorded in GNS84-C106 core [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF], once again related to the low depth of the collected core which would record a greater development of planktic superficial forms.

The onset of biozone 2 in the Levantine basin is characterized by an increase of N. incompta and by a drop of G. truncatulinoides (l.c) as well as by a significant increase of G. ruber (more than 90%) followed by the disappearance of G. inflata, G. sacculifer group and G. truncatulinoides l.c. From 8 kyr, the two species G. sacculifer group and G. inflata reappear again reaching 26 and 9% at 7.4±0.198 and 5.8±0.245 kyr respectively (Fig. 4c). The planktic foraminifera assemblage characterizing this biozone indicate the onset of enhanced water column stratification in the eastern Mediterranean basin during the S1 deposition. The peak of G. inflata observed after the end S1 is correlated with that recorded by [START_REF] Geraga | Short-term climate changes in the southern Aegean Sea over the last 48,000 years[END_REF] and [START_REF] Triantaphyllou | Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages[END_REF] in the south-eastern Aegean Sea suggesting the return of deep water ventilation and the onset of the modern circulation regime in the Levantine Basin.

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Journal Pre-proof Biozone 2 is correlated with the ecozone 4F and the lower part of the ecozone 3F of [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] in the Siculo-Tunisian Strait (Fig. 6), even though a higher percentage of G. inflata is observed in our record. On the basis of the planktic foraminiferal species, biozone 2 is also correlated to the biozone 2 of [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF] and with the compositionalzone F2 of Di Donato et al. ( 2008) (Fig. 6).

Biozone 1 Biozone 1 corresponds to the time interval between 5.6±0.34 and 0.4±0.10 kyr in the Siculo-Tunisian Strait, from 5.6±0.21 to 1.3±0.08 kyr in the Tyrrhenian Sea. This interval covers the upper interval of the middle Holocene and the whole period of the upper Holocene (the last 4.2 kyr). The onset of this biozone is marked by the reoccurrence of G. truncatulinoides r.c species (Fig. 4a,4b). In core REC13-53, no remarkable Annual SST changes can be observed since 5.6 kyr, with mean values around 19°C similar to those observed today. The planktic foraminifera assemblage is dominated by G. bulloides (23%) and G. inflata (around 30% with a peak of about 43% at 5.3 kyr) and by the subtropical species G. ruber (26%).The warmer species, including G. sacculifer group, G. calida and O. universa also characterize this biozone even if with low percentages. The subpolar species N. incompta is present with moderate percentage of about 15% in the lower boundary and starts to decline at about 4 kyr before disappearing. G. truncatulinoides reaches its highest abundances (up to 10%) with right coiling forms in the lower part between 4.3 and 2.3 kyr and left coiling forms in the middle and upper part of this interval from 4.1 kyr. Indeed, the re-occurrence of this species at 5.6 kyr has been previously recorded by [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF] even though the inferred chronology indicates for this bio event and older age (6.5 kyr) compared to our record. This phase shifts between the Tyrrhenian Sea cores (KET80-19, BS79-22, and BS79-38) could be due to a discrepancy in the age models, indeed in core KET80-19, the inferred bioevent is well constrained between two 14 C dated control points, whereas in both cores BS79-22 and BS79-38, the age model was rather based on the correlation of some regional Holocene cooling events observed in core MD95-2043 recovered far in the Alboran Sea [START_REF] Cacho | Dansgaard-Oeschger and Heinrich event imprints in Alboran Sea paleotemperatures[END_REF].

Biozone 1 is correlated respectively with the upper part of the ecozone 3F (marked by the reoccurrence of G. truncatulinoides), ecozone 2F and 1F of [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF], with the biozone 1 of [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF] and with the two compositional-zone F1b and F1a of [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] (Fig. 6) indicated also by the reoccurrence of G. truncatulinoides.

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Factors controlling the biochronological events in the Mediterranean Sea

In this study, in order to define biozones and/or biochronological events, we have compared the micropaleontological and climatic reconstructions ( 18 O and SST) obtained from three sediment cores recovered from the Siculo-Tunisian Strait, the Tyrrhenian Sea and the Levantine Basin and relate the changes in planktic foraminifera to different hydrological parameters such as temperature, productivity as well as water column stratification. The quantitative planktic foraminiferal distribution patterns, the succession of the biozones and the climatic records are reported in Fig. 4 and5.

Throughout these records, we have identified seven biozones in the western and central basins and six in the eastern Mediterranean basin during the last 24 kyr. We used the abundance variations of some planktic foraminiferal species living at different depths of the water column to interpret the palaeoceanographic changes along the sediment cores and to define the boundary of the different biozones.

A notable consistency is observed between the faunal record from the Siculo-Tunisian Strait and the Tyrrhenian Sea (Fig. 4 and5). In fact, the abundance of the colder species in the biozone 7 allows us to deduce that cold and productive waters occupied both the Siculo-Tunisian Strait [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] and the Tyrrhenian Sea [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF] at that time interval. In addition to the presence of the subpolar species (i.e. N. incompta and G. scitula), T. quinqueloba is also abundant with a peak at around 18.2 kyr considering the uncertainties in the age models recorded in both basins. Former studies in the Mediterranean Sea reported that high percentage of T. quinqueloba, that thrives in cool surface waters [START_REF] Rohling | 200 Year interruption of Holocene sapropel formation in the Adriatic Sea[END_REF], is linked to high surface water productivity [START_REF] Pujol | Distribution patterns of live planktic foraminifers as related to regional hydrography and productive systems of the Mediterranean Sea[END_REF][START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF], whereas the abundance of N. incompta is related to the presence of deep chlorophyll maximum (DCM) [START_REF] Rohling | Late Quaternary changes in Mediterranean intermediate water density and formation rate[END_REF][START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF]. The high abundance of G. scitula in these records should also reflect, during the late glacial period, enhanced vertical mixing which leads to enhanced eutrophic condition in the surface water masses [START_REF] Rogerson | The Azores Front since the Last Glacial Maximum[END_REF].

The LGM-Holocene temperature gradient of 5.5°C recorded in the Siculo-Tunisian Strait and Tyrrhenian Sea, is in agreement with reconstructed SST in the central and the western Mediterranean Sea [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF]Hayes et al., 2005;[START_REF] Essallami | Hydrological changes in the Mediterranean Sea over the last 30,000 years[END_REF]. This scenario is however different in core MD84-641 where SST difference between LGM and

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Journal Pre-proof Holocene is only  2.5°C most likely due to the high dissimilarity coefficients associated to the glacial SST estimates in this region, which make the inferred SST not very representative (Fig. 5e,5f). Indeed, the weak late glacial cooling was also reported in the eastern Mediterranean Sea by a previous study using artificial neural network (ANN) applied to planktic foraminiferal counts (Hayes et al., 2005).

During the Oldest Dryas/GS-2a climatic event (Biozone 6; Fig. 5a,5c), Annual SSTs are colder than the Holocene period by  9.5°C in the Siculo-Tunisian Strait and Tyrrhenian Sea.In fact, this cold period is associated with the disappearance of warm fauna and by the presence of the subpolar species N. incompta, G. scitula, and T. quinqueloba. This interval was previously identified in the Tyrrhenian Sea [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] and also well correlated with SSTs cooling by Uk 37 alkenones reconstructions recorded in the Alboran Sea, corresponding to the Heinrich event H1 [START_REF] Martrat | Similarities and dissimilarities between the last two deglaciations and interglaciations in the North Atlantic region[END_REF][START_REF] Hodell | Anatomy of Heinrich Layer 1 and its role in the last deglaciation[END_REF].

The onset of the post glacial warming, dated at 14.8±0.45 kyr in the Siculo-Tunisian Strait and at 14.5±0.55 kyr in the Tyrrhenian sea records, is characterized by an abrupt increase in Annual SST (7.5°C warmer than the glacial period) (Biozone 5; Fig. 5a,5c). This episode, attributed to the Bolling/Allerod/GI-1, is equally synchronously recognized in the South Adriatic [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF], Ionian [START_REF] Geraga | Northeastern Ionian Sea: Palaeoceanographic variability over the last 22 ka[END_REF] and Aegean Sea [START_REF] Triantaphyllou | Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages[END_REF]. In the Siculo-Tunisian Strait record, we distinguish three warming episodes corresponding to three abundance peaks of G. ruber, interrupted by two short colder events indicated by a slight increase in the abundance of N. incompta. Based on the ice-core stratigraphy proposed by [START_REF] Rasmussen | A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three synchronized Greenland ice-core records: Refining and extending the INTIMATE event stratigraphy[END_REF], the five episodes defined in the GI-1 period correspond to the Bølling/GI-1e, Older Dryas/GI-1d, Allerød/GI-1c, Intra Allerød/GI-1b and Allerød/GI-1a respectively match well the Annual SSTs variations in core REC13-53. In addition, the first occurrence of the transitional species G. truncatulinoides, even with low percentage, and the abundance of G. inflata at the base of this interval, suggests the presence of well-mixed water column during winter [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF], accompanied by relatively eutrophic waters [START_REF] Pujol | Distribution patterns of live planktic foraminifers as related to regional hydrography and productive systems of the Mediterranean Sea[END_REF]. The occurrence of G. inflata and G. truncatulinoides, was also recorded in the Levantine Basin at 15 kyr, demonstrating the presence of deep winter mixed layer. Indeed, G. inflata is considered as a species related to cool environment with relatively eutrophic conditions ( Pujol and Vegnaud-Grazzini, 1995;[START_REF] Rigual-Hernández | Seasonal and interannual changes of planktic foraminiferal fluxes in the Gulf of Lions ( NW Mediterranean ) and their implications for paleoceanographic studies : Two 12-year sediment trap records[END_REF][START_REF] Mallo | Low planktic foraminiferal diversity and abundance observed in a spring 2013 westeast Mediterranean Sea plankton tow transect[END_REF] and G. truncatulinoides is a deep dwelling species [START_REF] Hemleben | Modern planktonic foraminifera[END_REF][START_REF] Rigual-Hernández | Seasonal and interannual changes of planktic foraminiferal fluxes in the Gulf of Lions ( NW Mediterranean ) and their implications for paleoceanographic studies : Two 12-year sediment trap records[END_REF], which reproduces in winter near to the surface and continues to grow at greater depths [START_REF] Tolderlund | Seasonal distribution of planktonic foraminifera in the western North Atlantic[END_REF]; Rohling

J o u r n a l P r e -p r o o f

Journal Pre-proof et al., 1993). The first post glacial occurrence of G. inflata in the Mediterranean Sea at around 15 kyr was also documented by previous studies in the Tyrrhenian Sea and the South Adriatic Basin [START_REF] Jorissen | Late Quaternary central Mediterranean biochronology[END_REF][START_REF] Capotondi | Foraminiferal ecozones, a high resolution proxy for the late Quaternary biochronology in the central Mediterranean Sea[END_REF][START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF][START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF][START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF].

The drastic drop in Annual SST (9.5 and 7.5°C in the Siculo-Tunisian Strait and Tyrrhenian Sea, respectively) and the micropaleontological features prevailing during the Biozone 4 indicate a strong cold phase (Fig. 5a,5c) at the time of the Younger Dryas/GS-1 event. The onset of this biozone is marked by the strong increase of the subpolar species N. incompta, in response to this cooling event recorded both in the Siculo-Tunisian Strait and the Tyrrhenian Basin. This species is considered as a deep dweller [START_REF] Fairbanks | Foraminifera and chlorophyll maximum: Vertical distribution, seasonal succession, and paleoceanographic significance[END_REF] which reproduces on a synodic cycle [START_REF] Schiebel | Modern planktic foraminifera[END_REF] and that could well live at or below the thermocline [START_REF] Bé | Ecology of recent planktonic foraminifera: Part 2: Bathymetric and seasonal distributions in the Sargasso Sea off Bermuda[END_REF][START_REF] Bé | An ecological, zoogeographic and taxonomic review of recent planktonic foraminifera[END_REF][START_REF] Rigual-Hernández | Seasonal and interannual changes of planktic foraminiferal fluxes in the Gulf of Lions ( NW Mediterranean ) and their implications for paleoceanographic studies : Two 12-year sediment trap records[END_REF]. According to previous Mediterranean studies [START_REF] Rohling | 200 Year interruption of Holocene sapropel formation in the Adriatic Sea[END_REF][START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF][START_REF] Carboni | Late Quaternary paleoclimatic and paleoenviromental changes in the Tyrrhenian Sea[END_REF][START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF][START_REF] Donato | The palaeoclimatic and palaeoceanographic history of the Gulf of Taranto (Mediterranean Sea) in the last 15 ky[END_REF], the abundance of the N. incompta, indicates the development of a DCM. Even in the Levantine Basin, the fauna composition is marked by a slight reduction in the contribution of G. ruber, which rather indicates a decrease in the SST estimates in this region (Fig. 4c, 5e), while the increase of G. bulloides, suggests an enhanced surface primary productivity [START_REF] Pujol | Distribution patterns of live planktic foraminifers as related to regional hydrography and productive systems of the Mediterranean Sea[END_REF][START_REF] Lirer | Integrated stratigraphy for the Late Quaternary in the eastern Tyrrhenian Sea[END_REF] in this oligotrophic basin. The cooling phase was also observed in the nearby core MD84-632, from SST estimated by MAT [START_REF] Essallami | Hydrological changes in the Mediterranean Sea over the last 30,000 years[END_REF]. So, the effect of the Younger Dryas climatic change originated from the North Atlantic region was still sensitive as far as the Eastern Mediterranean area [START_REF] Almogi-Labin | Climatic variability during the last ∼90 ka of the southern and northern Levantine Basin as evident from marine records and speleothems[END_REF][START_REF] Revel | 100 , 000 Years of African monsoon variability recorded in sediments of the Nile margin[END_REF][START_REF] Mojtahid | Thirteen thousand years of southeastern Mediterranean climate variability inferred from an integrative planktic foraminiferal-based approach[END_REF].

The onset of the Holocene, with the biozone 3 is characterized by the warmer taxa G. ruber, associated with high Annual SSTs (19.5°C) (Fig. 4a, 4b, and5a, 5c). The abundance of the non-spinose species G. inflata, the reappearance of G. truncatulinoides synchronous with the decline of N. incompta in the lower part of this interval recorded both in the Siculo-Tunisian Strait and the Tyrrhenian Basin indicates a strong vertical mixing of the water column during winter [START_REF] Pujol | Distribution patterns of live planktic foraminifers as related to regional hydrography and productive systems of the Mediterranean Sea[END_REF][START_REF] Rohling | 200 Year interruption of Holocene sapropel formation in the Adriatic Sea[END_REF][START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF]. In fact, the lower abundance of N. incompta during this interval preceding the deposition of Sapropel S1, indicates a deep pycnocline between the LIW and the MAW that prevents the development of DCM [START_REF] Rohling | Late Quaternary changes in Mediterranean intermediate water density and formation rate[END_REF].

J o u r n a l P r e -p r o o f

Journal Pre-proof Biozone 2, corresponding to the upper part of the Early Holocene and the middle Holocene until 5.6 kyr, is marked by a SST drop of 3.5°C in the Tyrrhenian Sea (Fig. 5c). The SST decrease occurs in two steps from 9.5 to 8.2 and 7.9 to 5.6 kyr respectively. This cooling phase was also recorded in the southern Tyrrhenian Sea by [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF], in the Gulf of Lion by [START_REF] Melki | Abrupt climate change, sea surface salinity and paleoproductivity in the western Mediterranean Sea (Gulf of Lion) during the last 28 kyr. Palaeogeogr. J o u r n a l P r e -p r o o f Journal Pre-proof Palaeoclimatol[END_REF] and in the South Adriatic Sea by [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF]. However, such cooling was not recorded in the Gulf of Salerno [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]. This is probably attributed, as indicated in section 3.2, to the difference between the faunal assemblages of the shallow water core GNS84-C106 when compared to those from deeper Mediterranean basins.

This cooling period recorded in the western Mediterranean during the biozone 2, and in part coeval with the deposition of the Sapropel S1 in the Eastern Mediterranean basin, was characterized by a consistent change in the composition of the faunal assemblage marked by the increase of the subpolar species N. incompta. In addition, the simultaneous presence of G. inflata and N. incompta could indicate a period of cooling and/or an intensified contrast in seasonal conditions. In fact, since N. incompta is mainly found in association with DCM at the base of eutrophic layer, its higher abundance would suggest stratified waters with euphotic layer [START_REF] Pujol | Palaeoceanography of the last deglaciation in the Alboran Sea (western Mediterranean). Stable isotopes and planktonic foraminiferal records[END_REF][START_REF] Rohling | 200 Year interruption of Holocene sapropel formation in the Adriatic Sea[END_REF][START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF]. [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF] reported two short-term Uk 37 derived SST cooling (labelled C4 and C3) centered at 8 and 5.5 cal kyr BP respectively. This cooling (3.5-4°C with respect to the Holocene average) related to the high frequency of N. incompta is also recorded by using MAT estimates [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF]. Several studies carried out in the Mediterranean Sea show a similar cooling recorded in the Adriatic Sea at 8.2 kyr and between 7.3 to 6.1 kyr [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF] and in the Gulf of Lions since 9.9 kyr [START_REF] Melki | Abrupt climate change, sea surface salinity and paleoproductivity in the western Mediterranean Sea (Gulf of Lion) during the last 28 kyr. Palaeogeogr. J o u r n a l P r e -p r o o f Journal Pre-proof Palaeoclimatol[END_REF]. This Holocene cooling pattern is also corroborated by pollen data from Aegean Sea cores showing a temperature decrease by about 3°C at 7 and 4.7 kyr respectively [START_REF] Kotthoff | J o u r n a l P r e -p r o o f Journal Pre-proof Climate dynamics in the borderlands of the Aegean Sea during formation of sapropel S1 deduced from a marine pollen record[END_REF]. Conversely, our SST estimates in the Siculo-Tunisian Strait does not indicate a Middle Holocene cooling trend. [START_REF] Essallami | Hydrological changes in the Mediterranean Sea over the last 30,000 years[END_REF] display however, two short and lesser cooling events in the Siculo-Tunisian Strait at about 8.5 kyr and 7 kyr. Although δ 18 O data from Greenland ice cores (NGRIP, GISP2) do not show apparent cooling during this period except for the short event at 8.2 kyr, a reconstructed Greenland temperature in GISP2 ice core using argon and nitrogen isotopes exhibits a similar cooling trend to those observed in the central Mediterranean Sea [START_REF] Kobashi | Volcanic influence on centennial to millennial Holocene Greenland temperature change[END_REF]. Moreover, recent findings on the Greenland and Laurentide past ice sheet dynamic show short-term glacier re-advance centered at 10.4 kyr, J o u r n a l P r e -p r o o f 9.1 kyr, 8.1 kyr, and 7.3 kyr respectively, indicative of regional abrupt cooling [START_REF] Young | Deglaciation of the Greenland and Laurentide ice sheets interrupted by glacier advance during abrupt coolings[END_REF]. Hence, the most plausible feedback mechanism at the origin of such cooling phases could be related to a southward displacement of the polar front in the Mediterranean region initially affecting the Gulf of Lions since about 9.9 kyr and later the central part of the Tyrrhenian Sea. Either, the SST cooling, recorded in the Middle Holocene in the Aegean [START_REF] Kotthoff | J o u r n a l P r e -p r o o f Journal Pre-proof Climate dynamics in the borderlands of the Aegean Sea during formation of sapropel S1 deduced from a marine pollen record[END_REF] and Adriatic sea [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF] was attributed to the enhanced intensity of northerly air outbreaks from the Siberian high during winter and spring [START_REF] Rohling | Holocene atmosphereocean interactions: Records from Greenland and the Aegean sea[END_REF]. These cold and dry winter winds lead to buoyancy loss which is at the origin of the recovery of deep-water formation in both North Aegean and South Adriatic seas just after the sapropel S1 [START_REF] Kotthoff | J o u r n a l P r e -p r o o f Journal Pre-proof Climate dynamics in the borderlands of the Aegean Sea during formation of sapropel S1 deduced from a marine pollen record[END_REF][START_REF] Siani | Paleohydrology reconstruction and Holocene climate variability in the South Adriatic Sea[END_REF].

In the Levantine Basin, the distinct disappearance of the deep dwelling foraminifer species G. inflata and G. truncatulinoides in the biozone 2 (9.5-4.5 kyr) (Fig. 4c), seems likely to be in response to the stagnation conditions related to the cessation of the water column mixing and to the limited horizontal exchange of the water masses between the eastern and western basin.

In contrast to the southern Adriatic Sea [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF], G. inflata does not reappear in the core MD84-641 at the time corresponding to S1 interruption between 8.3 and 8.1 kyr [START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF]. This could also be due to the low sedimentation rate of this core particularly during S1 that would preclude the tracking of this short-term cooling. Moreover, the water mass stratification was likely related to increased biological productivity resulting from increased nutrient supply and to enhanced Nile river discharge and precipitation over the Mediterranean Sea (Kallel et al., 1997a(Kallel et al., , 1997b;;[START_REF] De Lange | Synchronous basin-wide formation and redox-controlled preservation of a Mediterranean sapropel[END_REF][START_REF] Mojtahid | Thirteen thousand years of southeastern Mediterranean climate variability inferred from an integrative planktic foraminiferal-based approach[END_REF]. Therefore, the eastern Mediterranean Sea seems to be characterized by slightly different oceanographic conditions from those occurred in the Tyrrhenian and the Siculo-Tunisian Strait records during the S1 interval.

During the biozone 1 interval corresponding to the upper part of the middle Holocene and the Upper Holocene, Annual SST estimates increase again and reach the same values (19°C) as those recorded at the beginning of the Holocene (Fig. 5a,5c). The presence of G. inflata and the reoccurrence of G. truncatulinoides at the onset of this interval starting from 5.6 kyr in the Tyrrhenian Sea and the Siculo-Tunisian Strait confirms the end of water stratification conditions and the establishment of vertical mixing and water convection during winter, as for the modern Tyrrhenian Sea [START_REF] Pujol | Distribution patterns of live planktic foraminifers as related to regional hydrography and productive systems of the Mediterranean Sea[END_REF][START_REF] Rohling | 200 Year interruption of Holocene sapropel formation in the Adriatic Sea[END_REF][START_REF] Carboni | Late Quaternary paleoclimatic and paleoenviromental changes in the Tyrrhenian Sea[END_REF].

J o u r n a l P r e -p r o o f

Our study on the abundance record of planktic foraminiferal species has displayed synchronous fluctuations, within age uncertainties at 2, at a regional scale even though some diachronisms have been observed. These findings allow us to identify four biochronological events (bio-events) which can be used as tie-points to establish or to improve the chronology of Mediterranean deep-sea cores. The first bio-event is relative to the peak of T. quinqueloba dated at 18.3±0.79 and 18.2±0.58 kyr in the Siculo-Tunisian Strait and the Tyrrhenian Sea, respectively. This bio-event was previously recorded at 18 kyr in the southern Tyrrhenian Sea [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF], in the Gulf of Salerno [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] and in the Siculo-Tunisian Strait [START_REF] Essallami | Hydrological changes in the Mediterranean Sea over the last 30,000 years[END_REF][START_REF] Rouis-Zargouni | Environmental and climatic changes in the central Mediterranean Sea (Siculo-Tunisian Strait) during the last 30 ka based on dinoflagellate cyst and planktonic foraminifera assemblages[END_REF]. The second bio-event corresponds to the first postglacial occurrence of G. inflata dated at 15.3±0.6 kyr, in the Siculo-Tunisian Strait and 15.1±0.78 kyr in the Tyrrhenian Sea and at 15.6±0.53 kyr in the Levantine Basin. This event was identified by [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF] in the Siculo-Tunisian Strait, by [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF] and [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] at 15.2 kyr in the Tyrrhenian Sea. The last postglacial disappearance of the subpolar species G.scitula at 14.3±0.32 kyr (Neapolitan Yellow Tuff tephra layer dated by 14 C) in the Tyrrhenian Sea and at 14.58 ± 0.32 kyr in the central basin indicates the third bio-event (Last Common postglacial Disappearance (LCD)). This event is also recorded in other well dated core of the Siculo-Tunisian Strait at 14 kyr [START_REF] Essallami | Hydrological changes in the Mediterranean Sea over the last 30,000 years[END_REF][START_REF] Rouis-Zargouni | Environmental and climatic changes in the central Mediterranean Sea (Siculo-Tunisian Strait) during the last 30 ka based on dinoflagellate cyst and planktonic foraminifera assemblages[END_REF]. This bio-event corresponding to LCD of G. scitula has been previously reported by several study carried out in the different basins od the Mediterranean [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF][START_REF] Minisini | Morphologic variability of exposed mass-transport deposits on the eastern slope of Gela Basin ( Sicily channel ) LT[END_REF][START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF][START_REF] Melki | Abrupt climate change, sea surface salinity and paleoproductivity in the western Mediterranean Sea (Gulf of Lion) during the last 28 kyr. Palaeogeogr. J o u r n a l P r e -p r o o f Journal Pre-proof Palaeoclimatol[END_REF][START_REF] Siani | Late glacial to Holocene planktic foraminifera bioevents and climatic record in the South Adriatic Sea[END_REF]. In the Levantine Basin, this event is however observed at 13.6±0.36 kyr despite being well constrained by 14 C pointers.

The latest bio-event corresponds to the reoccurrence of G. truncatulinoides r.c in the upper part of the Middle Holocene at 5.6±0.34 and 5.6±0.21 kyr in the central and the western basins respectively. This event was previously identified at 5.5±0.34 in the eastern Tyrrhenian Sea [START_REF] Lirer | Integrated stratigraphy for the Late Quaternary in the eastern Tyrrhenian Sea[END_REF], in the Gulf of Salerno [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF] and in the Sicily channel [START_REF] Minisini | Morphologic variability of exposed mass-transport deposits on the eastern slope of Gela Basin ( Sicily channel ) LT[END_REF].

Results from the central basin presents a striking similarity with those obtained in the western basin in terms of planktic foraminiferal assemblages and of biochronological events (Fig. 6).

However, minor differences in timing of the different bio-events and boundaries may be related to the available radiocarbon dataset but in general they can be considered synchronous considering the 2σ uncertainty. This finding suggests that these records reflect coeval responses to Mediterranean wide changes in sea-surface temperature and hydrology.

J o u r n a l P r e -p r o o f

Conclusions

We performed a high-resolution micropaleontological study to generate accurate climate and biochronological records along well dated deep sea cores recovered in three major basins of the Mediterranean Sea (the Siculo-Tunisian Strait, the Tyrrhenian Sea and the Levantine Basin). Quantitative variations of fossil planktic foraminiferal assemblages reconstructed along these three cores, covering the last 24 kyr, have permitted to identify seven successive biozones. Our results display that major changes in planktic foraminiferal assemblages have a similar pattern in the central and western basins unlike that of the Levantine Basin.

The comparison of our SSTs estimates and foraminiferal records with those of NGRIP icecore shows a similarity between the Greenland climate and the Mediterranean hydrology. This indicates that the main climate changes recorded in the North Atlantic are globally in phase with those observed in the Mediterranean region.

Abundance records of planktonic foraminifera display synchronous fluctuations at a regional scale. Four bio-events were hence identified during the last 24 kyr that can be used to establish or to improve the chronology of Mediterranean deep sea cores: i) the peak of T. quinqueloba at 18.3±0.79 and 18.2±0.58 kyr in the Siculo-Tunisian Strait and in the Tyrrhenian Sea respectively, ii) the first postglacial appearance of G. inflata dated at 15.3±0.6 kyr in the Siculo-Tunisian Strait, 15.1±0.78 kyr in the Tyrrhenian Sea and and at 15.6±0.53 kyr in the Levantine Basin, iii) the postglacial disappearance of the subpolar species G. scitula at 14.3±0.32 kyr in the western basin and at 14.58±0.32 kyr in the central basin (Last Common postglacial Disappearance) but at 13.6±0.36 kyr in the Levantine Basin and iiii) the reoccurrence of G. truncatulinoides r.c recorded at 5.6±0.34 and 5.6±0.21 kyr in the central and western basin respectively. Some observed differences may be due to the 14 C dating uncertainties during some time intervals. They can be used to establish or to improve the chronology of Mediterranean deep-sea cores.

These results provide an improvement and extension of previous climatic and biochronological events elaborated in the different basins of the Mediterranean Sea, facilitating climatic and microfaunal correlations at regional and global scale over the last 24 kyr. Mediterranean records mentioned in the text: Hole 963D [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF]; BS79-22 [START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF]; BS79-38 [START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF]; C69 [START_REF] Geraga | Short-term climate changes in the southern Aegean Sea over the last 48,000 years[END_REF]; GNS84-C106 [START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF]; NS-14 [START_REF] Triantaphyllou | Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages[END_REF] (Purple diamonds). [START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF][START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF][START_REF] Sbaffi | Millennial-to centennial-scale palaeoclimatic variations during Termination I and the Holocene in the central Mediterranean Sea[END_REF][START_REF] Geraga | Short-term climate changes in the southern Aegean Sea over the last 48,000 years[END_REF][START_REF] Donato | Coupled atmospheric and marine palaeoclimatic reconstruction for the last 35 ka in the Sele Plain-Gulf of Salerno area (southern Italy)[END_REF][START_REF] Triantaphyllou | Late Glacial-Holocene ecostratigraphy of the south-eastern Aegean Sea, based on plankton and pollen assemblages[END_REF].

  Oxygen isotope stratigraphyStable oxygen isotopes ( 18 O) were analyzed on the planktonic foraminifera species G.

  in the Tyrrhenian Sea as corroborated by deglacial lighter  18 O values as well as the compositionalzone F5a of Di Donato et al. (2008) considering the disappearance of G. ruber and the J o u r n a l P r e -p r o o f predominance of the cold and temperate species N. incompta, G. scitula and G. glutinata respectively. Biozone 5 Biozone 5 corresponds to the time interval between 14.8±0.45 and 12.9±0.37 kyr in the Siculo-Tunisian Strait, from 14.5±0.55 to 12.9±0.91 kyr in the Tyrrhenian Sea and between 15±0.48 and 13.5±0.35 kyr in the Levantine basin. A prominent Annual SST rise of about 7.5°C marks this biozone in the Siculo-Tunisian Strait and the Tyrrhenian Sea, corresponding

  as also corroborated by a coeval lowering of the planktic foraminifera  18 O values in the south Tyrrhenian Sea and compositional-zone F3 of Di Donato et al. ( 2008) (Fig. 6) equally characterized by the reoccurrence of G. ruber and the decrease of N. incompta.

Figure 1 :

 1 Figure 1: Map of the Mediterranean annual mean SSTs (°C, 1955-2012) from Word Ocean Atlas 2013 (http://odv.awi.de/de/data/ocean/world ocean atlas 2013 /) showing the locations of studiedcores: REC13-53, KET80-19, MD84-641 (Red diamonds) and the others

Figure 2 :

 2 Figure 2: a) Variations in oxygen isotope (δ 18 O) of the planktonic foraminifera Globigerina bulloides vs. depth. b) Age-depth relation for REC13-53 core based on 13 AMS 14 C dates.

Figure 3 :

 3 Figure 3: Comparison of palaeoclimatic record from REC13-53 core and Greenland ice-core over the last 24 kyr BP. (a) Oxygen isotope record from NGRIP ice core and event stratigraphy protocol recommended by the INTIMATE group (GS-2, Greenland stadial 2 (GS-2a-c are sub-stadials); GI-1,Greenland Interstadial 1 (GI-1a-e are sub-interstadials); GS-1, Greenland Stadial 1; Lowe et al., 2008) and the corresponding main climatic transitions (sensu Mangerud et al., 1974). (b) SST fluctuations generated by modern analogue technique. (c) Dissimilarity coefficient record. (d) Variations in oxygen isotope (δ 18 O) of the planktonic foraminifera Globigerina bulloides.

Figure 4 :

 4 Figure 4: a) Relative abundances of planktic foraminiferal assemblages in REC13-53 core vs. age (cal. Kyr BP), b) Relative abundances of planktic foraminiferal assemblages in KET80-19 core, c) Relative abundances of planktic foraminiferal assemblages in MD84-641 core.

Figure 5 :

 5 Figure 5: a) Annual SST (°C) by MAT in REC13-53 core, b) Dissimilarity coefficient in REC13-53 core, c) Annual SST (°C) by MAT in KET80-19 core, d) Dissimilarity coefficient in KET80-19 core, e) Annual SST (°C) by MAT in MD84-641 core and, f) Dissmilarity coefficient in MD84-641 core. The red star represents the present day temperature at the location of each core.

Figure 6 :

 6 Figure 6: Comparison between the biochronological schemes developed in this study with previous reconstructions in the adjacent basins[START_REF] Sprovieri | A high-resolution record of the last deglaciation in the Sicily Channel based on foraminifera and calcareous nannofossil quantitative distribution[END_REF][START_REF] Sbaffi | Response of the pelagic environment to palaeoclimatic changes in the central Mediterranean Sea during the Late Quaternary[END_REF]

Figure 2 Figure 3 Figure 4 Figure 5

 2345 Figure2

Figure 6

 6 Figure6

Table 1 .

 1 Summary of the core details used in this paper

		J o u r n a l P r e -p r o o f
					Water depth
	Core name	Location	Long.	Lat.
					(m)
	REC13-53	Siculo-Tunisian	12°08'E	36°45'N	1113

Table 2 .

 2 AMS radiocarbon dating obtained for REC13-53, KET80-19 and MD84-641 cores.

	code	Core	Depth	Conventional	Standard	Corrected	Median	Error median	Material
			(cm)	Radiocarbon	deviation	14C Age	Cal Age	Age
				Age	(±1σ)		(yr BP)	(2σ)

Acknowledgements

We are grateful to Ministry of Higher Education and Scientific research of Tunisia and "Ecole doctorale Sciences Fondamentales de la Faculté des Sciences de Sfax" for financial support.

We would like to thank the direction of international relations of the Paris-Sud Paris Saclay University for its Support. This work was financially supported by the French-Tunisian Joint Project PHC-Utique (Partenariats Hubert Curien: N° 14G1002). Financial support was also provided by the French INSU PALMEDS project. We thank the URANIA officers and crew for support and organization of the coring cruise in 2013. The ARTEMIS program is thanked for providing 14 C from the Accelerator Mass Spectrometer. The authors would also to thank two anonymous reviewers, and the editor Xavier Crosta for their constructive and stimulating reviews that deeply improved the manuscript.

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Supplementary data

Supplementary material