seanoe:86428 data@seanoe.org 2024-10-03 ISO 19115:2003/19139 1.0 Environmental changes in the Fleuve Manche paleoriver drainage system (Western Europe) directly linked to the North Atlantic sub-millennial climate variability across HS1 : a Bay of Biscay pollen record 2024 2024-10-03 Penaud Aurélie, Fersi Wiem, Toucanne Samuel, Sanchez Goni Maria Fernanda, Rossignol Linda, Naughton Filipa, Wary Mélanie, Eynaud Eynaud (2024). Environmental changes in the Fleuve Manche paleoriver drainage system (Western Europe) directly linked to the North Atlantic sub-millennial climate variability across HS1 : a Bay of Biscay pollen record. SEANOE. https://doi.org/10.17882/86428 Marine microfossils (dinoflagellate cysts and planktonic foraminifera) and geochemical (XRF-Ti/Ca)-based climatic records from a core located off the Fleuve Manche (FM) paleo-mouth (MD13-3438) have revealed that sustained warm summer sea surface temperatures (SSTs) during sub-millennial climate changes within HS1 (~18–14.7 ka) may have played a key role in the FM regime related to the European Ice Sheet (EIS) melting rate. In this study, we have analyzed the MD13-3438 pollen content over the HS1 at a mean resolution of ~50 years to test whether vegetation-based air temperatures were coupled to SSTs face to this rapid climate variability. First, our results highlight two major phases of pollen sources at site MD13-3438, preventing the pollen record to be interpreted as a continuous record of the evolution of vegetation and climate occupying a single watershed across HS1. The first phase, i.e. the HS1-a interval (~18–16.8 ka), is marked by strong occurrences of boreal pollen taxa (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 the 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 (~16.8–14.7 ka BP), is characterized by a deceleration of the EIS retreat and the drop of boreal pollen values at site MD13-3438 further signing a less influence of the upstream FM drainage system and thus a better characterization of pollen sources related with western FM tributaries. Superimposed to these two HS1 main phases, pollen fluctuations are concomitant with sub-millennial variability in the EIS deglaciation intensity. During the early HS1 (HS1-a), we discussed two short-term increases in the ratio between deciduous trees (Quercus-Corylus-Alnus) and herbaceous plants (Plantago-Amaranthaceae-Artemisia). These events were coeval with phases of increasing FM meltwater runoff and SST seasonality (i.e., dinocyst-based summer SST amplification). We associated these events with lower contribution of the upstream FM catchment as well as, possibly, atmospheric warming and regional sea-level positive oscillations. The HS1-b is 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 (16.3–15.6 ka BP) is coeval with large arrivals of iceberg from the Hudson strait in the Bay of Biscay and thus likely to a major sea-level positive oscillation associated with a phase of FM valley reworking. HS1-b3 (15.6–14.7 ka BP) corresponds to persistent arid conditions that preceded the subsequent more humid conditions recorded from 14.7 ka BP at the start of the Bölling-Alleröd. This work was supported by the French projects: ANR IDEGLACE, INSU RISCC, INSU ICE-BIO-RAM and ERC ACCLIMATE. This project includes regional, national and international collaborations, between Geo-Ocean laboratory (Brest University, Ifremer, Plouzané), EPOC laboratory (Bordeaux University, Pessac) and LOCEAN (Paris). We received funding from the CG29 (Conseil Général du Finistère, 29) and financial support from Geo-Ocean and EPOC laboratories. We thank Muriel Georget (EPOC; Bordeaux University) for the helpful support for laboratory assistance. This work was supported by the ISblue project, Interdisciplinary graduate school for the blue planet (ANR-17-EURE-0015), co-funded by a grant from the French government under the program "Investissements d'Avenir" as well as the project Hydroshifts (PTDC/CTA-CLI/4297/2021). Penaud Aurélie Univ Brest, CNRS, Ifremer, Geo-Ocean, UMR6538, F-29280 Plouzané, France Fersi Wiem Univ Brest, CNRS, Ifremer, Geo-Ocean, UMR6538, F-29280 Plouzané, France TOUCANNE Samuel Univ Brest, CNRS, Ifremer, Geo-Ocean, UMR6538, F-29280 Plouzané, France Sanchez Goni Maria Fernanda Univ Bordeaux, CNRS, UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), F-33615, Pessac France Ecole Pratique des Hautes Etudes (EPHE, PSL), 75014, Paris Rossignol Linda Univ Bordeaux, CNRS, UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), F-33615, Pessac France Naughton Filipa Portuguese Institute for Sea and Atmosphere (IPMA), Rua Alfredo Magalhaes Ramalho 6, 1495-006 Lisboa, Portugal Center of Marine Sciences (CCMAR), Algarve University, Campus de Gambelas, 8005-139 Faro, Portugal Wary Mélanie Univ Bordeaux, CNRS, UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), F-33615, Pessac France Eynaud Eynaud Univ Bordeaux, CNRS, UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), F-33615, Pessac France SEANOE https://www.seanoe.org/data/00752/86428/illustration.gif Heinrich Stadial 1 northern Bay of Biscay paleoriver runoff-discharge pollen and dinocysts land-sea approach Marine geology Geology ODATIS aggregation parameters and Essential Variable names 2024-09-16 geonetwork.thesaurus.external.theme.NVS.OD1 Marine geology SeaDataNet Parameter Disciplines 2021-04-07 geonetwork.thesaurus.external.parameter.NVS.P08 /Observational data/in-situ Type de jeux de donnée ODATIS 2024-10-15 geonetwork.thesaurus.local.theme.type_jeux_donnee CC-BY (Creative Commons - Attribution) Environmental changes in the Fleuve Manche paleoriver drainage system (Western Europe) linked to North Atlantic sub-millennial climate variability across Heinrich Stadial 1: Palynological evidence from the Bay of Biscay 2024 Elsevier BV Penaud Aurélie Fersi Wiem Toucanne Samuel Goñi Maria Fernanda Sanchez Rossignol Linda Naughton Filipa Wary Mélanie Eynaud Frédérique 10.1016/j.palaeo.2024.112512 Imprint of seasonality changes on fluvio-glacial dynamics across Heinrich Stadial 1 (NE Atlantic Ocean) 2021 Elsevier BV FERSI WIEM PENAUD AURÉLIE WARY MÉLANIE TOUCANNE SAMUEL WAELBROECK CLAIRE ROSSIGNOL LINDA EYNAUD FRÉDÉRIQUE 10.1016/j.gloplacha.2021.103552 10.17600/95200110 10.17600/13200040 oceans -15.0 30.0 42.0 65.0 XLS, XLSX https://www.seanoe.org/data/00752/86428/data/110581.xlsx WWW:DOWNLOAD-1.0-link--download Raw data Data - 258 KB https://doi.org/10.17882/86428 WWW:LINK-1.0-http--metadata-URL DOI of the product https://www.seanoe.org/data/00752/86428/ rel-canonical Seanoe One excel file with raw data acquired on study core MD13-3438 : - age-model (synchronization of study core MD13-3438 vs. age model of MD95-2002 in Toucanne et al., 2023) - Palynological analyses : pollen, dinocysts, other non-pollen palynomorphs - XRF data (complete file) - Planktonic foraminiferal data (only Neogloboquadrina pachyderma abundances)