Future climate change shaped by inter-model differences in Atlantic
Meridional Overturning Circulation response
Katinka Bellomo
Institute of Atmospheric Sciences and Climate, National Research Council, Turin, Italy, Institute of Atmospheric Sciences and Climate, National Research Council, Turin, Italy, Institute of Atmospheric Sciences and Climate, National Research Council, Turin, Italy
Corresponding Author:[email protected]
Author ProfileMichela Angeloni
Department of Physics and Astronomy, University of Bologna, Bologna, Italy, Department of Physics and Astronomy, University of Bologna, Bologna, Italy, Department of Physics and Astronomy, University of Bologna, Bologna, Italy
Author ProfileSusanna Corti
Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, Italy, Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, Italy, Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, Italy
Author ProfileAbstract
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-4xCO2 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 (ITCZ) 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.