The high central Andes have undergone significant hydroclimatic changes in recent decades, affecting ecosystems through glacier retreat, temperature variations, and shifts in precipitation type (e.g., rain, snow, and hail). Andean peatlands play a crucial role in water regulation and biogeochemical cycles and are highly sensitive to climate change. Here we reconstruct Late Holocene changes in organic matter (OM) accumulation and preservation over the last similar to 2500 years in a peatland of the south-central Peruvian Andes (4210 m a.s.l.) using the 96-cm APA01 core. We integrate bulk organic geochemistry with continuous X-ray fluorescence (XRF) core scanning, centered log-ratio (clr) transformation, principal component analysis (PCA), and accumulation-rate estimates. A key finding is the close temporal coherence between peat PC1-clr (a proxy for OM dynamics) and the decadal snow accumulation record from Quelccaya Ice Cap, indicating that peat carbon dynamics closely track the regional high-elevation moisture balance. Dry phases such as the Medieval Climate Anomaly (MCA) coincide with reduced OM accumulation, whereas cooler and wetter conditions during the Little Ice Age (LIA) favor enhanced OM preservation. Warming phases, such as the MCA, after LIA, and recent decades, showed high clastic mineral input possibly linked to an increased proportion of rain-to-snow precipitation and land use. These results highlight the sensitivity of Andean peatlands to hydroclimatic variability and underscore the vulnerability of their carbon storage and hydrological functions under ongoing climate change.

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.

Geochemical properties measured in core MD19-3575CQ, collected from the Del Cano Rise within the Subantarctic Zone in the Indian sector of the Southern Ocean, provide evidence of orbital-scale changes over eccentricity, obliquity, and precession cycles in phytoplankton productivity and its influence on the organic matter burial over the last 235 kyr. CaCO3 and biogenic opal contents varied oppositely with high CaCO3 and low biogenic opal contents during the interglacial periods and vice versa during the glacial periods. During the glacial periods, the biogenic opal production by diatoms increased as a result of more silica supply when the Subantarctic Front shifted northward across the Del Cano Rise. In addition, Fe-bearing dust and remobilized sediments likely enhanced diatom productivity. In contrast, biogenic carbonate production by coccolithophores and foraminifera was reduced during the glacial periods because of cold ocean temperature and competition for nutrients between coccolithophores and diatoms. More organic carbon was buried at the core site during the glacial periods than during the interglacial periods, probably in relation to a greater export efficiency by diatoms relative to coccolithophores as well as a better preservation of the organic matter when the Circumpolar Deep Water was less ventilated during the glacial periods.

The Southern Ocean is characterized by various ocean fronts that separate surface waters with different hydrographic properties. Ocean fronts’ position changed over glacial-interglacial cycles, which, consequently, affected surface water properties and productivity through time at any given location. The present study reconstructs changes in biogenic carbonate and opal burial at Del Caño Rise (DCR), Indian Ocean sector of the Southern Ocean, over the last three climate cycles. Based on Accelerator Mass Spectrometry radiocarbon dating of planktonic foraminifera as well as comparison of oxygen isotopes of planktonic foraminifera with LR04 stack, the studied core MD19-3575CQ, located today in the Subantarctic Zone, covers the last ~250,000 years. Biogenic carbonate content shows consistent low values during all glacial periods (average 32.4%) and high values during all interglacial periods (average 61.5%). In contrast, biogenic opal content increased during all glacial periods (average 12.8%), compared to interglacial periods (average 8.5%). TOC exhibited a similar pattern to the biogenic opal content, with higher values during glacial periods (average 0.38%) and lower values during interglacial periods (average 0.17%). The increased biogenic opal content during glacial periods is attributed to enhanced silica supply to surface waters due to northward migration of the Subantarctic Front, possibly shifting north of DCR during these periods. However, the relatively low biogenic opal content in the study area compared to other regions of the Polar Frontal Zone (average 55.6%) suggests insufficient silica supply to support high diatom production. The reduction in biogenic carbonate content during glacial periods is related to the decrease in coccolithophore productivity due to low ocean temperatures (~2ºC) and the competition for nutrients and light with diatoms. Despite the shallow water depth (~2400 m) at the core location, the weakened Atlantic Meridional Overturning Circulation and thickening of the corrosive Southern Ocean bottom waters during glacial times may have increased carbonate dissolution. Our study emphasizes that changes in surface water properties by ocean front’s migration impact on regional productivity, which may influence global biogeochemical cycles.

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.

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.

Paleoclimate studies in Patagonia show a high Holocene climate variability, strongly controlled by the intensity and latitudinal position of the Southern Westerly Winds. In this study, environmental and climate variability, and in particular winter precipitation, was reconstructed over the last centuries through sedimentological and geochemical analyses of a core from Lake Jeinimeni in North East Patagonia. Visual description, X-ray radiographies and thin section observations point to finely laminated sediments, made by fine sands and light brown clayey silts forming an annual deposition (varves) occasionally interrupted by two Hudson volcano-related tephras and 15 pluri-millimetre to pluricentimetre coarser sandy to gravely layers. Varve counting confirmed by Pb-210 and Cs-137 indicates a detrital sequence of at least 750 yr. Based on a correlation with local meteorological data for the 1930 -1988AD interval, varve thickness and statistical treatment of XRF geochemical data give information on transport pathway and sedimentary deposit conditions. The sandy laminae correspond to the deposition of high sedimentary load delivered by austral spring snowmelt whereas the clayey silt laminae result of particle settling in the water column during low hydrodynamical conditions. Thicker varves observed in dry conditions underline the importance of aeolian transport in sedimentary deposition. During locally dry and windy summer, the wind may erode and remobilise the sedimentary deposits along the lake margins. The sandy and gravely layers record massive erosional events due to proximal watershed perturbation driven by climatic or tectonic mechanisms. The clastic varves of Lake Jeinimeni document environmental decadal to multidecadal variability in East Patagonia over the last centuries. The more pronounced sediment transition around 1750 CE is consistent with the inception of the Little Ice Agetype event, in agreement with North Patagonian paleoclimate reconstructions derived from glacier advances, lacustrine varve thickness and tree-ring records. (C) 2021 Elsevier Ltd. All rights reserved.

Here we present a series of connected efforts aiming at curating sediment cores and their related data. Far to be isolated, these efforts were conducted within national structured projects and led to the development of digital solutions and good practices in-line with international standards and practices. Our efforts aimed at ensuring FAIR-compatible practices (Plomp, 2020; Wilkinson et al., 2016) throughout the life cycle of sediment cores, from fieldwork to published data. We adopted a step-by-step, bottom-up strategy to formalize a dataflow, mirroring our workflow. We hence created a fieldwork mobile application (CoreBook) to gather information during coring operations and inject them toward the French national virtual core repository “Cyber-Carothèque Nationale” (CCN). At this stage, the allocation of an international persistent unique identifier was crucial and we naturally chose the IGSN. Beyond the traceability of samples, the curation of analysis data remains challenging. Most international repository (e.g. NOAA palaeo-data, PANGAEA) have taken the problem from the top by offering facilities to display published dataset with persistant unique identifier (DOI). Yet, those data are only a fraction of the gross amount of acquired data. Moreover, those repositories have very low requirements when it comes to the preservation and display of metadata, in particular analytical parameters, but also fieldwork data which are essential for data reusability. Finally, these repositories do not permit to get a synoptic view on the several strata of analyses that have been conducted on the same core through different research programs and publications. A partial solution is proposed by the eLTER metadata standard DEIMS, which offers a discovery interface of rich metadata. In order to bridge the gap between generalist data repositories and samples display systems (such as CCN, but also IMLGS, to cite an international system), we developed a data repository and visualizer dedicated to the re-use of lake sediment cores, samples and sampling locations (ROZA Retro-Observatory of the Zone Atelier). This system is still a prototype but opens yet interesting perspectives. Finally, the digital evolution of science allows the worldwide diffusion of data processing freewares. In that framework, we developed “Serac” an open-source R package to establish radionuclide-based age models following the most common sedimentation hypotheses (serac,). By implementing within this R package the input of a rich metadata file that gathers links to IGSN and other quality metadata, we are linking fieldwork metadata, the physical storage of the core and the analytical metadata. Indeed, Serac also stores data processing procedure in a standardized way.. We hence think that the development of such softwares could help in the spreading of good practices in data curation and favour the use of unique identifiers. By tackling all aspects of data creation and curation throughout a lake sediment core life cycle, we are now able to propose a theoretical model of data curation for this particular type of sample that could serve as the sole for further developments of integrated data curation systems.

A better understanding of the past dynamics of local sectors of the Greenland ice sheet (GIS) with regards to ocean circulation and climate changes can be developed from proxy records derived from marine sedimentary archives. Here we investigate the post 9.1 cal. Kyr BP history of the western sector of the GIS from the XRF core scanner-derived geochemistry of a sediment core retrieved from Upernavik Trough, Melville Bay. The elemental signature of material derived from Melville Bay glaciers, Upernavik Isstrom and Rink Isbrae can be inferred from the geology of the bedrocks drained by these major ice streams of the western GIS. Changes in abundance of Ferich basaltic material reflect changes in West Greenland Current (WGC) strength. Contributions from Melville Bay glaciers were dominant during the early part of the record as a result of the rapid retreat of this stretch of the NW GIS. Atmospheric warming and strengthened WGC between 7.5 and 5 cal. Kyrs BP promoted contributions from distal southern sources of lithic material to the sedimentation over Upernavik Trough. The Neoglacial shift in climate and ocean circulation led to a general reduction in the delivery of lithic material from western GIS glacier outlets glaciers. The particular geomorphology of the fjord hosting Rink Isbrae as well as the important depth of the Uummannaq Trough likely explain the high relative contribution of this glacier to the lithic sedimentation over Upernavik Trough during the later part of the Holocene despite a weakened WGC.

La gestion des donnees constitue l’un des defis de l’Open science dans le contexte de la loi « Pour une republique numerique ». Ceci est particulierement important dans le domaine des sciences de la Terre et de l’environnement dans lequel la multiplication des echantillons de terrain et de mesures qui sont realisees sur chaque conduit a une croissance exponentielle du nombre de donnees. Dans le cas de l’etude des carottes sedimentaires, l’engouement pour les methodes paleoenvironnementales, pour repondre a des problematiques variees allant des chroniques de contaminations recentes aux evolutions climatiques pluriseculaires a plurimillenaire, voire plus, participe de cette croissance. Or, l’absence de systemes d’information dediee ne permet pas de capitaliser sur cette grande richesse en reliant les donnees entre elles. Dans cette contribution, nous presentons un systeme developpe dans le cadre du programme Equipex CLIMCOR afin de bancariser les informations de terrain collectees lors du prelevement de carottes sedimentaire. Ce systeme est constitue de deux modules : i) CoreBook, qui est une application mobile de collecte d’information sous Android et ii) la Cyber-carotheque nationale (Base MySQL), qui est un portail d’import, de consultation et de diffusion des informations. CoreBook a ete pense pour etre embarquee sur une tablette durcie du commerce. Elle apporte une plus-value lors des operations de carottage sur le terrain. Il comprend notamment des fonctionnalites comme le reperage des carottages precedents, une aide a la navigation et aux operations d’ancrage ou encore la visualisation en coupe des carottages multi-sections et/ou multi-trous, ou en carte des carottages simple section. Optimise pour la carottage multi-sections multi-sequences, il est adapte a tout type de methode de carottage (carottier russe, gravitaire, piston stationnaire, etc.). Chaque entite de recherche (labo) a la possibilite de creer des configurations de materiels dans le portail « Cyber-carotheque » en constituant un referentiel qu’il retrouvera dans le CoreBook ; ce referentiel facilite la selection d’outils une fois sur le terrain et associe automatiquement les parametres de carottage et d’outils aux futurs echantillons ce qui permet de gagner en precision et qualite. Les donnees collectees par CoreBook sont directement synchronisables avec la cyber-carotheque. Un format d’echange permettra egalement d’alimenter les bases de donnees locales de laboratoire. La cyber-carotheque permet de gerer les configurations materielles des entites de recherche. Elle recueille les metadonnees des operations de prelevement de carottes, soit via CoreBook, soit via un fichier d’import respectant un format specifique. Interoperable, elle est capable, via des web-services, de moissonner des bases existantes et d’etre moissonnee par celles-ci par des protocoles standardises (OGC WFS). Une fois entree dans la Cyber-carotheque, chaque echantillon recoit un identifiant unique au format international IGSN. Equivalent d’un DOI pour les echantillons geologiques, cet identifiant permet de tracer la carotte et les operations de terrain ayant permis de la prelever, a chaque fois qu’elle est utilisee pour une publication ou integree dans un systeme d’information. Il s’agit d’une etape prealable indispensable vers la bancarisation, la qualite, le partage et la reutilisabilite des donnees. Pour l’utilisateur final, la Cyber-carotheque offre des fonctionnalites de recherche et constitue une base de reference, structuree, ouverte et standardise permettant de connaitre les echantillons deja preleves dans une region donnee, ou encore de suivre l’activite d’un groupe de chercheur ou d’une entite de recherche. En prenant le probleme de la gestion des donnees a la base, au niveau des operations de terrain, le systeme CoreBook & Cyber-carotheque fournit a la communaute scientifique nationale un socle solide pour developper des bases de donnees, soit pour la gestion interne des donnees et/ou des echantillons, soit pour evoluer vers des systemes plus integres en associant de donnees analytiques. La Cyber-carotheque est accessible a l’adresse : https://cybercarotheque.fr/index.php, on y trouve notamment le lien et les instructions pour telecharger l’application CoreBook.

High coastal erosion rates along the beaches of the Médoc peninsula urge for the study of the Pleistocene and Holocene deposits buried under the modern dune. Those deposits are known to be exceptionally rich in archaeological remains (from the Mesolithic at least). The aggressive predation of these fossil deposits by the sea explains the urgency of exploring their content and their sedimentological history. Within these formations, the “Lède du Gurp” archaeological site located on the shore, on the administrative boundary of Soulac-sur-Mer and Grayan-et-l’Hôpital, is of tremendous value for palaeogeographical and palaeoenvironmental reconstructions of the Médoc peninsula. This site has preserved remains of dense anthropic activity but also evidence of the history of the estuary’s migration before our contemporary era (i.e. recent centuries). Here we present results of new sedimentological investigations conducted as part of the LITAQ project on and around the site. Continuous and undisturbed sections several metres thick (up to 3.5 m) have been obtained by sampling (sediment slides) and coring operations in the field and studied for their lithostratigraphy (using classic and X-ray imaging coupled with spectrocolorimetry, X-ray fluorescence and grain-size analyses together with radiocarbon dating) along with simultaneous archaeological investigations. Our study refines the palaeoenvironmental evolution of the site over at least the Neolithic period and supports previous interpretations of the origin of these atypical lithofacies, i.e. the deposition of a thick Holocene sequence of clays and peats in a depression associated with karstification processes. Our new datings and observations suggest the possible occurrence of a thermokarst system during the coldest phases of the last deglaciation.

The past two million years of eastern African climate variability is currently poorly constrained, despite interest in understanding its assumed role in early human evolution1–4. Rare palaeoclimate records from northeastern Africa suggest progressively drier conditions2,5 or a stable hydroclimate6. By contrast, records from Lake Malawi in tropical southeastern Africa reveal a trend of a progressively wetter climate over the past 1.3 million years7,8. The climatic forcings that controlled these past hydrological changes are also a matter of debate. Some studies suggest a dominant local insolation forcing on hydrological changes9–11, whereas others infer a potential influence of sea surface temperature changes in the Indian Ocean8,12,13. Here we show that the hydroclimate in southeastern Africa (20–25° S) is controlled by interplay between low-latitude insolation forcing (precession and eccentricity) and changes in ice volume at high latitudes. Our results are based on a multiple-proxy reconstruction of hydrological changes in the Limpopo River catchment, combined with a reconstruction of sea surface temperature in the southwestern Indian Ocean for the past 2.14 million years. We find a long-term aridification in the Limpopo catchment between around 1 and 0.6 million years ago, opposite to the hydroclimatic evolution suggested by records from Lake Malawi. Our results, together with evidence of wetting at Lake Malawi, imply that the rainbelt contracted toward the Equator in response to increased ice volume at high latitudes. By reducing the extent of woodland or wetlands in terrestrial ecosystems, the observed changes in the hydroclimate of southeastern Africa—both in terms of its long-term state and marked precessional variability—could have had a role in the evolution of early hominins, particularly in the extinction of Paranthropus robustus. A multiple-proxy reconstruction for the catchment of the Limpopo River and of sea surface temperatures in the Indian Ocean provides evidence for hydroclimatic changes that may have been important in hominin evolution.

(1) AGEs Geology, University of Liege, Quartier Agora, Liege, Belgium (nathalie.fagel@uliege.be), (2) Aquatic Systems Research Unit, EULA – Chile Environmental Sciences Centre, University of Concepcion, Casilla 160-C, Concepcion, Chile, (3) Patagonian Ecosystems Research Center (CIEP), Coyhaique, Chile, (4) UMR Environnements et Paléoenvironnements Océaniques et Continentaux, Université de Bordeaux, France

Dansgaard–Oeschger and Heinrich events constitute ones of the most enigmatic features of the last glacial period. Many studies have focused on their characteristic millennial climatic variability, testing atmospheric/cryospheric/oceanic couplings, but major uncertainties and discrepancies still remain. A new scenario, robustly supported by an approach coupling paleoreconstructions and freshwater hosing experiments simulating Heinrich-type perturbations, has recently emerged. Reconciling most of the up to now hypothesized theories, it suggests the occurrence of a regional seesaw between a cooled-down North Atlantic Ocean and warmed-up Nordic Seas during cold atmospheric phases, in relation to enhanced subsurface advection of warm Atlantic waters re-emerging in the Norwegian Sea. The associated ocean warming, thus reaching Nordic basins at a critical location beyond the Faeroe-Shetland sill, is proposed to be involved in the concomitant release of European icebergs. Here we further investigate this promising scenario over the 35–41 ka BP interval by (i) outlining its precise spatial pattern in a crucial area, i.e. the junction between the North Atlantic and the Norwegian Sea close to European ice-sheets, (ii) resolving its very fine temporal and regional evolution during critical transitions associated with the onset of warm advection, i.e. Greenland Interstadial to Greenland Stadial and Greenland Interstadial to Heinrich Stadial, and (iii) assessing its impact on the spatio-temporal dynamic of iceberg discharges from the European and Laurentide ice-sheets during cold stadial episodes especially including Heinrich event 4.

ABSTRACTThe last glacial millennial Heinrich and Dansgaard–Oeschger events have been the subject of many studies in recent decades. However, significant uncertainties remain, notably regarding associated oceanic mechanisms. Here we investigate the evolution of hydrographical conditions in the 3–41 ka cal BP interval of core MD99‐2285 located in the southern Norwegian Sea. Our results reveal an unusual scheme with: (i) warm Greenland interstadials marked by a relatively cold and homogeneous upper water column seasonally ice‐covered and active deep water formation, (ii) cold Greenland and Heinrich stadials marked by a warm, low‐salinity and nearly sea ice‐free surface layer with iceberg calving, separated by a strong halocline from a colder and saltier subsurface layer, as well as strongly reduced deep convection, and (iii) close to modern Holocene oceanic conditions, but showing significant differences from interstadial conditions. Hence, our work strongly suggests different deep‐water convection modes in the Nordic Seas, with, notably, interstadial deep water formation mainly forced by brine release. According to our results, the transition from the glacial mode of deep water formation to the modern open ocean convection mode might have occurred at the end of deglaciation/beginning of the Holocene, when both modes probably occurred.

Managing scientific data is probably one the most challenging issues in modern science. In plaeosciences the question is made even more sensitive with the need of preserving and managing high value fragile geological samples: cores. Large international scientific programs, such as IODP or ICDP led intense effort to solve this problem and proposed detailed high standard work- and dataflows thorough core handling and curating. However many paleoscience results derived from small-scale research programs in which data and sample management is too often managed only locally – when it is… In this paper we present a national effort leads in France to develop an integrated system to curate ice and sediment cores. Under the umbrella of the national excellence equipment program CLIMCOR, we launched a reflexion about core curating and the management of associated fieldwork data. Our aim was then to conserve all data from fieldwork in an integrated cyber-environment which will evolve toward laboratory-acquired data storage in a near future. To do so, our demarche was conducted through an intimate relationship with field operators as well laboratory core curators in order to propose user-oriented solutions. The national core curating initiative proposes a single web portal in which all teams can store their fieldwork data. This portal is used as a national hub to attribute IGSNs. For legacy samples, this requires the establishment of a dedicated core list with associated metadata. However, for forthcoming core data, we developed a mobile application to capture technical and scientific data directly on the field. This application is linked with a unique coring-tools library and is adapted to most coring devices (gravity, drilling, percussion etc.) including multiple sections and holes coring operations. Those field data can be uploaded automatically to the national portal, but also referenced through international standards (IGSN and INSPIRE) and displayed in international portals (currently, NOAA’s IMLGS). In this paper, we present the architecture of the integrated system, future perspectives and the approach we adopted to reach our goals. We will also present our mobile application through didactic examples.