AMOC decline and recovery in a warmer climate
Paulo Nobre, Sandro F. Veiga, Emanuel Giarolla, André Lanfer Marquez, MANOEL B. DA SILVA, Vinícius Capistrano, Marta Malagutti, Júlio Pablo Reyes Fernández, Helena Cachanhuk Soares, Marcus Jorge Bottino, Paulo Y. Kubota, Silvio Nilo Figueroa, José Paulo Bonatti, Gilvan Sampaio, Fernanda Casagrande, Mabel Calim Costa, Carlos A. Nobre
Abstract
This study presents novel insight into the mechanisms of Atlantic Meridional Overturning Circulation (AMOC) reduction and its recovery under a warmer climate scenario. An one-thousand-year-long numerical simulation of a global coupled ocean-ice-atmosphere climate model, subjected to a stationary atmospheric radiative forcing, depict a coherent picture of the Arctic sea ice melting as a trigger for the initial AMOC reduction, along with decreases in the northward fluxes of salt and heat. Further atmospheric-driven ocean processes contribute to an erosion of the stable stratification of the fresher, yet colder waters in the surface layers of the North Atlantic, contributing to the recovery of a permanently altered AMOC.