A vast ocean conveyor carries water from Greenland through the Atlantic for 350 years and shapes rainfall in Brazil; 15,400 years ago, it suddenly surged beyond today's strength

Recent sediment analyses indicate that the Atlantic Meridional Overturning Circulation has undergone surprising fluctuations in intensity. This crucial system distributes heat throughout the Atlantic Ocean, ultimately affecting global climate conditions. While earlier studies suggested a consistent weakened state, new evidence reveals a more variable dynamic, particularly during previous periods of reduced circulation. Grasping these alterations is essential for anticipating future climate transitions.