Reconstruction of the Grande Pile Eemian using inverse modeling of biomes and delta C-13

• Published in: Quaternary Science Reviews
• Main Authors: Rousseau, Denis-Didier, Hatté, Christine, Guiot, Joel, Duzer, Danièle, Schevin, Patrick, Kukla, G.
• Other Authors: Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement IRD : UR226, Lamont-Doherty Earth Observatory (LDEO), Columbia University New York, Lehrstuhl für Geomorphologie, Universität Bayreuth, Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Géochrononologie Traceurs Archéométrie (GEOTRAC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2006
• Subjects: HEAT-FLUX; OCEAN CIRCULATION; NORDIC SEAS; ARCTIC ECOSYSTEMS; LAST INTERGLACIAL PERIOD; SEDIMENTARY ORGANIC-MATTER; EUROPEAN POLLEN RECORDS; NORTH-ATLANTIC; CLIMATE-CHANGE; FLUCTUATIONS; [SDE.MCG]Environmental Sciences/Global Changes; Arctic; Climate change; Ice Sheet; Nordic Seas; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/halsde-00339202; https://doi.org/10.1016/j.quascirev.2006.06.011

International audience A new method to reconstruct past climatic conditions between 130 and 100 ka BP from pollen and isotopic data is applied to a previously unanalyzed Grande Pile core, GPXXI. We applied the inverse mode to the Biome4 vegetation model. The method utilizes delta C-13, measured in parallel to the pollen samples as a constraint for the model. First the biomes and the delta C-13 simulated by the model are compared with the biome allocation of the pollen data. The delta C-13 to be simulated takes into account the degradation effect on the preserved organic matter. This procedure allows the reconstruction of the mean annual temperature and precipitation as well as the mean temperatures of the warmest and coldest months. We show that during the Eemian sensu stricto, the reconstructed precipitation is similar to modern values with low variability. The cold stadials and the penultimate glaciation are characterized by very low precipitation amounts. The temperature estimates, however, indicate differences with several oscillations identified. The peak values are reached at about 124-125 ka BP, but two other warm intervals are also identified. The variations in temperature appear to be related to sea-surface temperature oscillations in the North Atlantic region and are also in agreement with the timing of ice sheet build-up in the Northern Hemisphere. Seasonal variations are also identified in the estimated temperatures of the warmest and coldest months. (c) 2006 Elsevier Ltd. All rights reserved.