Sensitivity of the Atlantic Meridional Overturning Circulation to the melting from northern glaciers in climate change experiments

• Published in: Geophysical Research Letters
• Main Authors: Swingedouw, D., Braconnot, P., Marti, O.
• Other Authors: Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), 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)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Modelling the Earth Response to Multiple Anthropogenic Interactions and Dynamics (MERMAID), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-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)-Direction de Recherche Fondamentale (CEA) (DRF (CEA))
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2006
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Sea ice
• Online Access: https://hal.science/hal-03023546; https://hal.science/hal-03023546/document; https://hal.science/hal-03023546/file/2006GL025765.pdf; https://doi.org/10.1029/2006GL025765

International audience A weakening of the Atlantic Meridional Overturning Circulation (AMOC) in the next century is simulated by most state-of-the-art coupled models but none of them accounted for land-ice melting. Here we evaluate the impact of this melting on future climate projection using the IPSL-CM4 coupled ocean-atmosphere model. For this purpose we use two different versions of the model, one with a crude land-ice melting parameterization, and the other without. The analysis compares results of experiments where atmospheric CO 2 increases by 1%/yr, performed with the two versions of this model. The AMOC is reduced by 47% when the melting of land-ice is considered, and represents an extreme melting scenario. This reduction is of 21% without this melting. It is shown that this difference in AMOC impacts the northern hemisphere mostly through the sea-ice cover feedback.