Impact of solar forcing on the surface mass balance of northern ice sheets for glacial conditions

• Published in: Earth and Planetary Science Letters
• Main Authors: Woillez, Marie-Noëlle, Krinner, Gerhard, Kageyama, Masa, Delaygue, Gilles
• Other Authors: 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), 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), Modélisation du climat (CLIM), 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)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2012
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-02931514; https://doi.org/10.1016/j.epsl.2012.04.043

International audience The climate of the last glacial period has been punctuated by abrupt changes, termed the Dansgaard–Oeschger (DO) events, occurring every 1500–4500 yr. So far, the cause of these events, which involve changes in the thermohaline circulation, remains an open issue. It has been proposed that small changes in the freshwater flux in the North Atlantic, possibly coming from cyclic variations in solar activity, could act as a pacemaker and synchronize the events. Here we use the general circulation model IPSL_CM4 to investigate the impact of changes in the total solar irradiance (TSI) on the freshwater flux coming from ablation of the Northern hemisphere ice sheets. We test four different TSI values between 1360 and 1375 W/m2, and in this range establish a linear relationship between TSI and ablation rates over different sectors of the ice sheets. Our results show that a change in TSI smaller than 1%, that would be undetectable in paleo-records, can trigger changes in the freshwater flux in the North Atlantic at an amplitude similar to the one required to synchronize abrupt events in the climate model of intermediate complexity CLIMBER. Given the uncertainties on the past solar activity, we conclude that the hypothesis of a solar origin of the periodicity of D/O events cannot be ruled out and that the relationship between ice ablation and TSI variations is worth being further investigated.