The climate of the Last Glacial Maximum (LGM) in southern Europe has been thoroughly documented. Still, discrepancies exist between the climatic information provided by pollen data, which mainly indicate steppe vegetation and thus arid conditions, and some model simulations that rather suggest large amounts of precipitation, notably in winter. Here, we investigate the regional vegetation and seasonal climate from 28 ka to 10 ka using published pollen sequences from five sites, including core SU81-18 located on the western Iberian Margin, ODP Site 976 in the Alboran Sea, Padul in Southeastern Spain, Lago Grandi di Monticchio (Monticchio) in southern Italy and Xinias in Greece. Pollen-based estimates of seasonal temperatures and precipitation are reconstructed using the Modern Analogue Technique with the latest version of the Eurasian Modern Pollen Database (EMPD2), which comprises numerous samples from cold environments and provides potential analogues for the LGM. The results highlight a coherent regional pattern of vegetation dynamics that appears tightly linked to winter temperature and precipitation influenced by the westerlies. Most importantly, we reconstruct high winter and annual precipitation during the LGM at all study sites, with values comparable to, or even exceeding, those estimated for the B & oslash;lling/Aller & oslash;d. Our results indicate high variability in rainfall, particularly along the Atlantic margin, and lower variability further east, notably in the Alboran Sea, suggesting a climatic front located between the two regions. Two phases of increased precipitation are evidenced in our records, one from 24 to 22.5 ka and the other from 21.5 to 19.5 ka. The timing of these humid intervals is in phase with two main glacier advances in the European Alps, suggesting a consistent regional atmospheric pattern. Increased precipitation is attributed to the southward displacement of the jet stream and the westerlies due to the maximum extension of the Northern Hemisphere ice sheets. Conversely, the dry phases might correspond to a weakening or latitudinal shift of the westerlies. Indications of tenuous arboreal vegetation growth during the LGM are observed at the Iberian sites, but not at Monticchio and Xinias, where a cold climate may have prevented forest development. We hypothesize that the classic Mediterranean gradient with increasing dryness and temperature from west to east may have been amplified by the influence of the Fennoscandian and Alpine ice sheets due to the Rossby wave breaking of the jet stream west of the Alps.

The present work is based on the analysis of two hemipelagic sequences collected off the two main fluvial tributaries that enter the southern Bay of Biscay along the Aquitaine margin: the Gironde estuary, for core JB7ST3c retrieved from the West-Gironde mud patch; and the Adour river, for core MD03-2693 retrieved from the Capbreton canyon meanders. Their positioning, at the northern and southern edges of the Aquitaine shelf, not only allows us to obtain a synoptic view of the southern Bay of Biscay past oceanography, but, over the last thousand years covered by these archives, also provides access to key contextual elements related to local as well as global hydroclimatic forcings. This article focuses on the interpretation of the sedimentological signal based on key X-ray fluorescence (XRF) elemental profiles obtained along the cores, within the framework of coherent age models newly built for the two sequences. The consistency of the two records allows us to robustly relate the evolution of the XRF profiles to the hydroclimatic regime of the Bay of Biscay, and to compile and discuss a chronicle of the environmental events that have marked the sites. This is achieved through a regional scale analysis, encompassing synchronous occurrences on the proximate continent, complemented by a broader synoptic perspective within the context of the well-documented European and North Atlantic historical frames. This chronicle is pivotal in comprehending the correlation between continental and oceanic regimes along the Euro-Atlantic margin, in addition to their links to the climatic processes that govern the Northern Hemisphere region. Our results clearly discriminate specific climatic trends, highlighting the Medieval Warm Period, the Little Ice Age and the Current Warm Period as contrasted intervals. The climatic patterns identified during these specific phases are discussed in the light of recent advances in our knowledge of their modes of variability, and raise the question of teleconnections between the North Atlantic Oscillation, Atlantic sea-surface conditions and dynamics, together with atmospheric ones and especially storminess over Europe.

Climate archives have revealed that rapid climate changes took place during the last glacial period, whereby cold intervals in the North Atlantic region were associated with Atlantic Meridional Overturning Circulation (AMOC) slowdowns1–6. Some of these cold intervals were also characterized by ice rafted debris (IRD) layers in North Atlantic sediments, stemming from iceberg discharges from the northern hemisphere ice sheets7–9. The IRD layers were first interpreted as the imprint of intense melt water input by icebergs to the surface ocean that hindered deep-water formation and led to the observed AMOC slowdowns. However, subsequent studies dismissed iceberg discharges as a cause of AMOC slowdown on the basis of observations from marine cores from the Reykjanes Ridge region, indicating that surface cooling systematically precedes the arrival of IRD10,11. Here we analyse well-resolved IRD and reconstructed surface ocean temperature records from glacial North Atlantic sediments, together with numerical simulations. We show that in vast portions of the North Atlantic, there is no systematic lead of surface cooling over the arrival of IRD. Our results therefore invalidate the arguments made that AMOC slowdowns were not triggered by iceberg discharges and show that surface freshening is a plausible physical trigger of AMOC slowdown.

Marine microfossils (dinoflagellate cysts and planktonic foraminifera) and geochemical (XRF-Ti/Ca)-based matic records from a core (MD13-3438) located off the Fleuve Manche (FM) paleo-mouth have revealed sustained warm summer sea surface temperatures (SSTs) during sub-millennial climate changes within (similar to 18-14.7 ka) may have played a key role in the FM regime related to the European Ice Sheet (EIS) melting In this study, we have analyzed the MD13-3438 pollen content over the HS1 at a mean resolution of similar to 50 years test whether vegetation-based air temperatures were coupled to SSTs face to this rapid climate variability. our results highlight two major phases of pollen sources at site MD13-3438, preventing the pollen record interpreted as a continuous record of the evolution of vegetation and climate occupying a single watershed HS1. The first phase, i.e. the HS1-a interval (similar to 18-16.8 ka), is marked by strong occurrences of boreal pollen (especially Picea-Abies). Considering their spatial distribution and the coalescence of the British and Scandinavian ice sheets into the North Sea during the Last Glacial Maximum, these taxa probably originated from North European Plain, i.e., eastern FM tributaries (east of the Rhine River), where cool-humid conditions generally prevailed. Then, the second phase, i.e. the HS1-b interval (similar to 16.8-14.7 ka BP), is characterized deceleration of the EIS retreat and the drop of boreal pollen values at site MD13-3438 further signing influence of the upstream FM drainage system and thus a better characterization of pollen sources related western FM tributaries. Superimposed to these two HS1 main phases, pollen fluctuations are concomitant sub-millennial variability in the EIS deglaciation intensity. During the early HS1 (HS1-a), we discuss two short-term increases in the ratio between deciduous trees (Quercus-Corylus-Alnus) and herbaceous plants (Plantago-Amaranthaceae-Artemisia). These events are coeval with phases of increasing dinocyst-based SST seasonality through summer SST amplification). We associate these events with lower contribution of the upstream catchment as well as, possibly, atmospheric warming and regional sea-level positive oscillations. The HS1-b composed of three main phases that appear more influenced by the downstream FM drainage system. HS1-b1 (16.8-16.3 ka BP) corresponds to the driest and coldest conditions west of the Rhine River. HS1-b2 (16.3-15.5 ka BP) is coeval with large arrivals of iceberg from the Hudson strait in the Bay of Biscay and likely to a major sea-level positive oscillation associated with a phase of FM valley reworking. HS1-b3 (15.5-14.7 ka BP) corresponds to persistent arid conditions that preceded the subsequent more humid tions recorded from 14.7 ka BP at the start of the Bolling-Allerod.

Species assemblage composition of marine microfossils offers the possibility to investigate ecological and climatological change on time scales inaccessible using conventional observations. Planktonic foraminifera - calcareous zooplankton - have an excellent fossil record and are used extensively in palaeoecology and palaeoceanography. During the Last Glacial Maximum (LGM; 19,000 - 23,000 years ago), the climate was in a radically different state. This period is therefore a key target to investigate climate and biodiversity under different conditions than today. Studying LGM climate and ecosystems indeed has a long history, yet the most recent global synthesis of planktonic foraminifera assemblage composition is now nearly two decades old. Here we present the ForCenS-LGM dataset with 2,365 species assemblage samples collected using standardised methods and with harmonised taxonomy. The data originate from marine sediments from 664 sites and present a more than 50% increase in coverage compared to previous work. The taxonomy is compatible with the most recent global core top dataset, enabling direct investigation of temporal changes in foraminifera biogeography and facilitating seawater temperature reconstructions.

The Gironde estuary in SW France is the largest in Western Europe and has attracted human populations since prehistoric times. From the 1970s to the 1990s, intense archaeological research was undertaken on the long and highly dynamic coastline just south of the estuary mouth. In recent years, the combined action of increased coastal erosion and human pressure has proved a serious threat to the integrity of archaeological sites in the area. As a consequence, a whole array of previously unrecorded archaeological remains across the intertidal zone and coastal strip is being exposed. In this context, innovative interdisciplinary research since 2014 is yielding new information about the settlement and landscape dynamics and about the long-term interaction between human societies and the environment. The sedimentary context and the exceptional preservation conditions of organic remains have made possible a multi-proxy approach combining archaeological, geomorphological, palaeobiological, and archaeoentomological methods. In this paper we discuss the different approaches and the way they jointly contribute to the project. The results obtained so far from this multi-proxy approach challenge the traditional view of the historic occupation and the landscape dynamics around the Gironde estuary from prehistoric times to antiquity. They show that the intense occupation of this area during certain periods of human history is related to the development of marshy environments, which can now be analyzed at higher temporal resolution owing to this approach.

A multiproxy sedimentological study was conducted on five sediment cores retrieved between 67 and 79 degrees N in the Greenland/Iceland/Norwegian seas in order to infer a common chronostratigraphic model for the selected cores. This model is based on the use of a series of geochemical, physical and micropaleontological proxies which are routinely measured in sedimentological investigations of marine sediment cores: the major and minor element content derived from X-Ray Fluorescence (XRF) core scanner analyses; the lightness and color of the sediment derived from spectrophotometry analyses; the magnetic susceptibility of the sediment; the distribution of planktonic foraminiferal assemblages combined to coccolith stratigraphy (acme zones) providing preliminary stratigraphic tie points. All those proxies are correlated independently between the five sediment cores. Our results demonstrate that high resolution studies using those standard paleoceanographical tools are powerful for establishing core-to-core correlation. A chronostratigraphical framework is proposed based on the correlation of the planktonic delta O-18 isotopic record obtained in core M17KC03 with the LR04 benthic delta O-18 reference stack. A comparison between the M17KC03 stratigraphy and other dated cores from the sub-polar North Atlantic confirms the robustness of the approach. Our study suggests that XRF core scanner-derived elemental ratios (especially those related to Ca), the lightness L* and the coccolith-based biostratigraphy provide robust stratigraphic tie-points at the scale of the whole Greenland/Iceland/Norwegian seas. The elemental ratio Sr/sum, the magnetic susceptibility, and planktonic foraminiferal records have a more local stratigraphic significance in the GIN seas. Over the last 1100 ka BP, our datasets are indicative of: (1) an excursion of Ca content and planktonic foraminiferal abundances during MIS 11, (2) an overall decrease toward present of both the detrital content (with the exception of values characterizing MIS 12) and of the magnetic susceptibility of sediments deposited during Glacials.

We combine consistently dated benthic carbon isotopic records distributed over the entire Atlantic Ocean with numerical simulations performed by a glacial configuration of the Norwegian Earth System Model with active ocean biogeochemistry in order to interpret the observed Cibicides delta C-13 changes at the stadial-interstadial transition corresponding to the end of Heinrich Stadial 4 (HS4) in terms of ocean circulation and remineralization changes. We show that the marked increase in Cibicides delta C-13 observed at the end of HS4 between similar to 2000 and 4200 m in the Atlantic can be explained by changes in nutrient concentrations as simulated by the model in response to the halting of freshwater input in the high-latitude glacial North Atlantic. Our model results show that this Cibicides delta C-13 signal is associated with changes in the ratio of southern-sourced (SSW) versus northern-sourced (NSW) water masses at the core sites, whereby SSW is replaced by NSW as a consequence of the resumption of deep-water formation in the northern North Atlantic and Nordic Seas after the freshwater input is halted. Our results further suggest that the contribution of ocean circulation changes to this signal increases from similar to 40 % at 2000 m to similar to 80 % at 4000 m. Below similar to 4200 m, the model shows little ocean circulation change but an increase in remineralization across the transition marking the end of HS4. The simulated lower remineralization during stadials compared to during interstadials is particularly pronounced in deep subantarctic sites, in agreement with the decrease in the export production of carbon to the deep Southern Ocean during stadials found in previous studies.

Marine Isotope Stage (MIS) 4 (ca. 71-57 ka; within the Middle Weichselian Substage) is considered a significant Pleistocene glaciation, but it remains poorly constrained in comparison to that of the Late Weichselian Last Glacial Maximum (LGM; ca. 29-19 ka, during MIS 2), or even the Late Saalian MIS 6 (ca. 190-130 ka). Most MIS 4 glacial landforms in Europe were erased by the more extensive LGM ice advance, precluding a robust reconstruction of its extent and dynamic through time. Marine sedimentary archives, in preserving the source-to-sink sediment transfer signals of ice-sheet and glacier processes, help to bridge this gap. Here, the signals west of the European Ice Sheet (EIS) are tracked for MIS 4 from the deep Bay of Biscay (NE Atlantic), which was the outlet for Fennoscandian Ice Sheet (FIS) sediment-laden meltwater during extensive glaciations, specifically when the British-Irish Ice Sheet (BIIS) and the FIS coalesced into the North Sea (as during MIS 6 and the LGM). Sedimentological, geochemical, and mineralogical proxies reveal the absence of FIS-derived material in Bay of Biscay sediment throughout MIS 4, which indicates that FIS meltwater and huge river systems from the North European Plain never drained into the Bay of Biscay at that time. This suggests that contrary to MIS 6 and the LGM, the BIIS and FIS were not likely large enough to coalesce and form a (grounded) ice bridge onto the North Sea, thus confirming geomorphic evidence for a significant, but relatively limited, glaciation in Europe during MIS 4. Closer to the Bay of Biscay, ice-marginal fluctuations of the BIIS are identified in the Celtic-Irish Sea region from the deep-sea record. More specifically, our findings suggest an early retreat of the Irish Sea Ice Stream as soon as ca. 68-65 ka, a few millennia before the demise of the EIS, and the Northern Hemisphere ice sheets as a whole, during Heinrich Stadial (HS) 6. This pattern is similar to that already recorded during MIS 2. Finally, this study reveals that the MIS 4 period in Western Europe corresponds, as for MIS 2, to a complex combination of general ice advance interspersed by preliminary-to-final EIS demises highlighted by HS conditions.

Reconstructions of ocean primary productivity (PP) help to explain past and present biogeochemical cycles and climate changes in the oceans. We document PP variations over the last 50 kyr in a currently oligotrophic subtropical region, the Gulf of Cadiz. Data combine refined results from previous investigations on dinocyst assemblages, alkenones, and stable isotopes (18O, 13C) in planktonic (Globigerina bulloides) and endobenthic (Uvigerina mediterranea) foraminifera from cores MD04‐2805 CQ and MD99‐2339, with new isotopic measurements on epibenthic (Cibicides pachyderma‐Cibicidoides wuellerstorfi) foraminifera and dinocyst‐based estimates of PP using the new n = 1,968 modern database. We constrain PP variations and export production by integrating qualitative information from bioindicators with dinocyst‐based quantitative reconstructions such as PP and seasonal sea surface temperature and information about remineralization from the benthic Δδ13C (difference between epibenthic and endobenthic foraminiferal δ13C signatures). This study also includes new information on alkenone‐based SST and total organic carbon which provides insights into the relationship between past regional hydrological activity and PP regime change. We show that PP, carbon export, and remineralization were generally high in the NE subtropical Atlantic Ocean during the last glacial period and that the Last Glacial Maximum (LGM) had lower Δδ13C than the Heinrich Stadials with sustained high PP, likely allowing enhanced carbon sequestration. We link these PP periods to the dynamics of upwelling, active almost year‐round during sadials, but restricted to spring‐summer during interstadials and LGM, like today. During interstadials, nutrient advection through freshwater inputs during autumn‐winter needs also to be considered to fully understand PP regimes.

The physical, sedimentological, mineralogical and elemental geochemical properties of sediment cores AMD1803‐02BC and 01PC from the Cape Norton Shaw Inlet were investigated to reconstruct glacial sediment discharges from southeastern Manson Icefield and document the impact of ice–ocean interactions on the sediment dynamics and opening of the North Water Polynya (NOW) in northwestern Baffin Bay since the last deglaciation. Laminated glaciomarine sediments rich in quartz and feldspar are observed prior to 11 cal. ka BP and were probably deposited by hyperpycnal currents triggered by the local retreat of the southern margin of the Innuitian Ice. Detrital proxies suggest that Early Holocene sediment dynamics were mainly influenced by sea ice and iceberg rafting and meltwater discharges related to the deglaciation of eastern Smith (~11 to 10.65 cal. ka BP) and Jones (~10.7 cal. ka BP) sounds. This also provides an upper limit to the timing of formation of the NOW. The high detrital carbonate contents during 8.8 to 6.6 cal. ka BP confirm that enhanced carbonate‐rich sediment export from Nares Strait to northern Baffin Bay occurred during and after the deglaciation of Kennedy Channel (8.8 to 8.2 cal. ka BP). Canadian Shield sediment inputs have dominated since 6.6 cal. ka BP, indicating that sedimentation is mainly influenced by Cape Norton Shaw glacier discharges. The lower level of sedimentation recorded in core 01PC during the Middle to Late Holocene suggests an accelerated landward retreat of the Cape Norton Shaw glaciers in response to warmer marine conditions. During the Neoglacial period, higher sedimentation rates and detrital proxies in the cores suggest increased glacial erosional processes, probably associated with the long‐term declines in boreal summer insolation and glacier growth. Finally, mineralogical and grain‐size data in core 02BC support the idea that increased Arctic atmospheric temperatures have had an important influence on the glacial dynamics during the industrial period.

The main drivers of Europe's climate during the Holocene result from the coupling and interplay of external and internal radiative processes with the shifting patterns of many dynamic components (e.g. glaciers, ocean currents, wind fields, vegetation cover). Those driving forces were expressed across a range of geographical scales, from local to global, in a diverse set of records forming a patchwork of evidence as to the fundamental pacing effect of climate on past ecosystems. Various sedimentary deposits resulting from those complex forcing contexts bear climatic signatures that it is not always easy to disentangle especially with respect to local factors. The present paper focuses on a coastal archaeological site on the Medoc peninsula (the Lède du Gurp site in south-western France) that records Holocene palaeoenvironmental changes, decoded here century after century and integrated with ongoing events on a pan-North-Atlantic scale. Based on updated geoarchaeological approaches, thanks to new applications of proxies, especially X-ray fluorescence (XRF) core scanning methods for this article, continuous sedimentary records have been analysed in order to reconstruct a regional framework for past ecosystem events, including events potentially related to human activity. Our work identifies signals on various scales in the record under study, with both long- and short-term trends and local and global imprints, but all closely bound up with proximal North Atlantic Ocean dynamics. It highlights how western European environments (and so populations) were dependent upon the linearity of climate evolution at the key Northgrippian/Meghalayan transition.

The northern Bay of Biscay has previously proven its great potential for recording the 'Fleuve Manche' paleoriver (i.e., the largest Pleistocene river in Europe) fluvio-glacial activity. In this study, new dinoflagellate cyst (dinocyst) analyses have been carried out at sub-centennial resolution in core MD13-3438 to reconstruct the deglacial history of the 'Fleuve Manche' paleoriver runoff coupled with European Ice Sheets (EIS) fluctuations across Heinrich Stadial 1 (HS1: 18.2-14.6 ka BP), a key extreme climatic event of the last glacial period. Prior to Heinrich Event (HE) 1 (16.7-14.6 ka BP), the onset of HS1 (18.2-16.7 ka BP) appears here marked by enhanced 'Fleuve Manche' paleoriver runoff, materialized by laminated deposits. Our work suggests a novel sub-centennial scale subdivision of the early HS1 (laminated) interval into 5 sub-phases when episodes of substantial fluvioglacial delivery concomitant with warm summers alternate with episodes of moderate runoff associated with extended cold winters. We argue that multidecadal seasonal changes played a key role in the hydrological regime of western Europe during this HS1 interval, with the retreat of the southern limb of the EIS, and associated influx of meltwater and fluvio-glacial delivery, which were strongly influenced by those multidecadal changes in seasonality. Interestingly, our paleoclimatic record not only evidences the crucial role of seasonality in controlling climate and hydrological variations during HS1 but also shows a remarkable echo with reconstructions from the western Mediterranean Basin, highlighting common climate forcings at regional scale during the last deglaciation.

Since its existence, paleoceanography has relied on fossilized populations of planktonic foraminifera. Except for some extreme environments, this calcareous protist group composes most of the silty-to-sandy fraction of the marine sediments, i.e., the foraminiferal oozes, and its extraction is probably the simplest among the currently existing set of marine fossil proxies. This tool has provided significant insights in the building of knowledge on past climates based on marine archives, especially with the quantification of past hydrographical variables, which have been a turning point for major comprehensive studies and a step towards the essential junction of modelling and paleodata. In this article, using the modern analog technique and a database compiling modern analogs (n = 1007), we test the reliability of this proxy in reconstructing paleohydrographical data other than the classical sea-surface temperatures, taking advantage of an update regarding a set of extractions from the World Ocean Atlas for transfer functions. Our study focuses on the last glacial period and its high climatic variability, using a set of cores distributed along the European margin, from temperate to subpolar sites. We discuss the significance of the reconstructed parameters regarding abrupt and extreme climate events, such as the well-known Heinrich events. We tested the robustness of the newly obtained paleodata by comparing them with older published reconstructions, especially those based on the complementary dinoflagellate cyst proxy. This study shows that the potential of planktonic foraminifera permits going further in reconstructions, with a good degree of confidence; however, this implies considering ecological forcings in a more holistic perspective, with the corollary to integrate the message of this fossil protist group, i.e., the obtained parameters, in light of a cohort of other data. This article constitutes a first step in this direction.

Marine microcharcoal records provide invaluable information to understand changes in biomass burning and its drivers over multiple glacial and interglacial cycles and to evaluate fire models under warmer climates than today. However, quantitative reconstructions of burnt area, fire intensity and frequency from these records need calibration studies of the current fire-microcharcoal relationship. Here, we present the analysis of microcharcoal concentration and morphology in 102 core-top sediment samples collected in the Iberian margin and the Gulf of Cádiz. We show that microcharcoal concentrations are influenced by the water depth or the distance from the river mouth. At regional scale, the mean microcharcoal concentrations and microcharcoal elongation (length to width ratio) show a marked latitudinal variation in their distribution, primarily controlled by the type of burnt vegetation in the adjacent continent. High microcharcoal concentrations in marine sediments represent rare, large and intense fires in open Mediterranean woodlands. Based on these results, the increasing trend of microcharcoal concentrations recorded since 8 ka in the well-known marine sedimentary core MD95-2042 off the Iberian margin indicates the occurrence of large and infrequent fires of high intensity due to the progressive degradation of the Mediterranean forest and the expansion of shrublands.

The northern Bay of Biscay has proven, in previous studies, its great potential for recording fluvio-glacial activity thanks to its proximity to the mouth of the ‘Fleuve Manche’ paleoriver, the largest Pleistocene river in Europe. In the present work, new dinoflagellate cyst (dinocyst) analyses have been carried out at pluri-decadal resolution in core MD13-3438. Our principle objective is to reconstruct the deglacial history of the ‘Fleuve Manche’ paleoriver runoff coupled with European glacial fluctuations across Heinrich Stadial 1 (HS1: 18.2-14.6 ka BP), a key extreme climatic event of the last glacial period. We identify warm conditions preceding HS1, at the end of the Last Glacial Maximum, highlighted by a significant penetration of the warm and salty North Atlantic Drift (NAD) at the study site. The onset of HS1 is marked by enhanced ‘Fleuve Manche’ paleoriver runoff leading to the formation of laminated deposits, here referred to as the ‘HS1-a laminated interval’. We also suggest a novel pluri-decadal scale subdivision of HS1 in 7 sub-phases including 5 sub-phases within the laminated interval (HS1-a1 to HS1-a5: 18.2–16.7 ka BP) and 2 sub-phases during the Heinrich Event 1 (HE1: HS1-b: 16.7–15.6 ka BP including the ‘conventional’ HE1 layer at ~16 ka and HS1-c: 15.6-14.6 ka BP). Within HS1-a, substantial terrigenous inputs are coeval with high marine primary productivity and large sea surface salinity drops, with reconstructed values as low as 29 psu at the study site. This results from substantial fluvio-glacial delivery of the ‘Fleuve Manche’ paleoriver in response to the seasonal influx of meltwater associated with the retreat of the southern limb of the European Ice Sheets. Additionally, in this interval, pluri-decadal variability is here detected. Two major events (HS1-a2: 17.8–17.6 ka BP and HS1-a4: 17.4–17 ka BP) of huge fluvial inputs (i.e., substantial erosional processes in the ‘Fleuve Manche’ basin and strong stratification of the water column) are revealed, and occur concomitantly with warm summers. In the rest of HS1-a (HS1-a1: 18.2–17.8 ka BP, HS1-a3: 17.6–17.4 ka BP and HS1-a5: 17–16.7 ka BP), fluvio-glacial discharges via the ‘Fleuve Manche’ paleoriver, although significant, were comparatively moderate induced by decreased seasonality dominated by extended cold winters that could have limited the EIS melting. We argue for the main role of seasonality (i.e., temperature contrast between summer and winter) within HS1-a in controlling fluvio-glacial dynamics. Subsequent intervals HS1-b and HS1-c (first and second phase of HE1, respectively), show a significant decrease of fluvial inputs as well as extended sea-ice cover occurrences and extremely low sea surface temperatures (-1.8°C), especially during HS1-b (associated to Laurentide-sourced Ice Rafted Debris). At the end of HS1-c, the NAD influence in the study area marks the onset of the transition to the warm Bolling/Allerod interval.Interestingly, our paleoclimatic record (i) confirms the crucial role of seasonality in controlling climate variations during the HS1 interval and (ii) shows a remarkable echo with reconstructions from the western Mediterranean Basin, highlighting common regional forcings acting on multi-scale climate variability during the last deglaciation.