Future climate change shaped by inter-model differences in Atlantic meridional overturning circulation response

• Published in: Nature Communications
• Main Authors: Bellomo, Katinka, Angeloni, Michela, Corti, Susanna, von Hardenberg, Jost
• Other Authors: EC | Horizon 2020 Framework Programme
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Science and Business Media LLC 2021
• Subjects: General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; North Atlantic
• Online Access: http://dx.doi.org/10.1038/s41467-021-24015-w; http://www.nature.com/articles/s41467-021-24015-w.pdf; http://www.nature.com/articles/s41467-021-24015-w

Abstract In climate model simulations of future climate change, the Atlantic Meridional Overturning Circulation (AMOC) is projected to decline. However, the impacts of this decline, relative to other changes, remain to be identified. Here we address this problem by analyzing 30 idealized abrupt-4xCO 2 climate model simulations. We find that in models with larger AMOC decline, there is a minimum warming in the North Atlantic, a southward displacement of the Inter-tropical Convergence Zone, and a poleward shift of the mid-latitude jet. The changes in the models with smaller AMOC decline are drastically different: there is a relatively larger warming in the North Atlantic, the precipitation response exhibits a wet-get-wetter, dry-get-drier pattern, and there are smaller displacements of the mid-latitude jet. Our study indicates that the AMOC is a major source of inter-model uncertainty, and continued observational efforts are needed to constrain the AMOC response in future climate change.