The combined impact of global warming and AMOC collapse on the Amazon Rainforest

Abstract The Amazon rainforest is threatened by both anthropogenic climate and land use change. Observations and some modelling results suggest that the Amazon rainforest might abruptly transition to a savanna-like state and that this transition would be practically irreversible. Here, we analyze observations of precipitation, temperature and tree cover together with high-resolution simulations of several comprehensive climate models to investigate the combined effect global warming and a potential collapse of the Atlantic Meridional Overturning Circulation (AMOC) will have on the Amazon. Our results show that, while high levels of warming lead to forest dieback, an AMOC collapse would tend to stabilize the forest by increasing rainfall and decreasing temperature in most of the Amazon basin. Although an AMOC collapse would have devastating impacts globally, our results hence suggest that it may delay or even prevent parts of the Amazon rainforest from transitioning to a savanna-like state.