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With Dr. Regina Rodrigues The climate of the northern region of South America, including the Amazon River basin, is highly dependent on the temperatures of the tropical South Atlantic. This is because the Intertropical Convergence Zone, a band of strong precipitation oriented from west to east just north of the equator, shifts north-south with the warmer temperatures of the tropical Atlantic. Excessive rain and floods in northern South America are often associated with the southward shift of the ITCZ when the waters of the tropical South Atlantic are warmer than those in the tropical North Atlantic. On the other hand, droughts in this region are linked to a northward shift of the ITCZ when the tropical North Atlantic is warmer. Therefore, a skilful forecast of rainfall in the region depends on accurately predicting the temperatures of the tropical South Atlantic. Unfortunately, the South Atlantic has been historically under-researched and as such regional forecast systems and global climate models do not simulate well the South Atlantic. To make matters worse, climate change alters the distribution of heat between the South and North Atlantic. For instance, a slowdown of the Atlantic Meridional Overturning Circulation (AMOC) due to climate change would lead to less heat being transported from the South Atlantic to the North Atlantic and, thus, to a warming of the South Atlantic. There is evidence that this is already happening. However, most of the AMOC research focuses on changes in the North Atlantic. Therefore, more research is needed to fully understand the past, present and future changes in the South Atlantic and the climate of South America.