Why is the Gulf Stream and AMOC so important to our climate?

Complex ocean currents keep Europe warm and bring rain to Africa, but could they come to an end?

The Atlantic Meridional Overturning Circulation (AMOC) is a system of ocean currents within the Atlantic Ocean, transporting warm water north towards the Arctic and returning cold water south towards Antarctica. The Gulf Stream is a component of AMOC, which carries warm water from the Gulf of Mexico, up along the eastern coastline of the United States. AMOC and the Gulf Stream enable heat to be distributed around our planet, and ensure Europe experiences milder weather compared to Canada, despite being on a similar latitude.

AMOC’s currents are driven by changes in water density due to changes in ocean salinity and temperature. Increasing ocean temperatures and freshwater flows from melting ice sheets due to climate change, have the potential to weaken AMOC. This could lead to cooler temperatures in Europe and a drop in rainfall in key agricultural areas in places like Africa and Asia, in turn affecting millions of people.

Host Claire Graham talks to the BBC’s Climate Editor Justin Rowlatt. Produced by Cathy Young for the BBC World Service.