Influence of regional parameters on the surface mass balance of the Eurasian ice sheet during the peak Saalian (140kya)

• Published in: Global and Planetary Change
• Main Authors: Colleoni, Florence, Krinner, Gerhard, Jakobsson, Martin, Peyaud, Vincent, Ritz, Catherine
• Other Authors: Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS), Department of Geology and Geochemistry Stockholm, Stockholm University, ANR IDEGLACE, The Berto Bolin Center of Climate Research, Explora doc, Lavoisier cotutelle, ANR IDEGLACE, ANR-05-BLAN-0310,IDEGLACE,Impact de Décharges d'Eau douce provenant de la GLace continentale sur le Climat Européen et méditerranéen(2005)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2009
• Subjects: surface mass balance; Eurasian ice sheet; Saalian; proglacial lakes; dust SST; vegetation; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; [SDE.MCG]Environmental Sciences/Global Changes; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Ice Sheet; Tundra
• Online Access: https://hal.archives-ouvertes.fr/hal-00411080; https://doi.org/10.1016/j.gloplacha.2009.03.021

International audience Recent geologically-based reconstructions of the Eurasian ice sheet show that during the peak Saalian (≈140kya) the ice sheet was larger over Eurasia than during the Last Glacial Maximum (LGM) at ≈21kya. To address this problem we use the LMDZ4 atmospheric general circulation model to evaluate the impact on the Saalian ice sheet's surface mass balance (SMB) from proglacial lakes, dust deposition on snow, vegetation and sea surface temperatures (SST) since geological records suggest that these environmental parameters were different during the two glacial periods. Seven model simulations have been carried out. Dust deposition decreases the mean SMB by intensifying surface melt during summer while proglacial lakes cool the summer climate and reduce surface mel on the ice sheet. A simulation including both proglacial lakes and dust shows that the presence of the former parameter reduces the impact of the latter, in particular, during summer. A switch from needle-leaf to tundra vegetation affects the regional climate but not enough to significantly influence the SMB of the nearby ice margin. However, a steady-state vegetation in equilibrium with the climate should be computed to improve the boundary conditions for further evaluations of the vegetation impact on the ice sheet's SMB. Finally, changes of the SST broadly affect the regional climate with signicant consequences for the SMB.