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Abstract:
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The Atlantic meridional overturning circulation has a vast potential for abrupt climate change due to its large heat transport through the ocean and its nonlinear dynamics . Because of these unique properties , this paper investigates how the climate of West Africa and Europe will respond to a shutdown of the Atlantic meridional overturning circulation at the end of the 21st century . Here we use a regional climate model with 90 -km grid spacing is forced by an idealized sea -surface temperature anomaly , based upon coupled atmosphere /ocean global model water hosing experiments , with a business -as -usual global warming scenario to discover how West African and European climate will change .
In both the boreal spring and summer , cooling in the eastern Atlantic is associated with a strong intensification and eastward extension of the North Atlantic subtropical high over Europe throughout the depth of the atmosphere , a strengthening of the heat low over West Africa at low levels , and a weakening of the Saharan High in the upper atmosphere . Rainfall rates also decrease markedly throughout most of West Africa and Europe : in spring , rainfall rates decrease by 50 -80 % over Sahelian Africa , in summer rainfall over Europe decreases by up to 90 % , while precipitation over West Africa is reduced by 40 % . |