Circulation of Concern

The Atlantic Meridional Overturning Circulation (AMOC) is a vast system of ocean currents. It basically carries heat; carbon and nutrients from the tropics towards the Arctic Circle. When these currents arrive, their waters cool and sink into the deep ocean, distributing energy around the Earth. The AMOC includes the Gulf Stream and is a key component of global climate regulation. A paper in Science Advances suggests the AMOC is heading towards a tipping point (https://www.theguardian.com/environment/2024/feb/09/atlantic-ocean-circulation-nearing-devastating-tipping-point-study-finds). Tipping points occur, when changes can't be reversed. The AMOC is being eroded, by faster than expected melts of Greenland's glaciers and the Arctic ice sheets. This melt pours freshwater into the ocean and weakens the mixing effect. The AMOC's power has declined by 15% since 1950. It's currently in its weakest state for 1000 years. The Science Advances paper used a combination of modelling and measurements. It concluded, contra to earlier expectations, that a slow decline in AMOC could lead to its sudden collapse in less than 100 years. The climate, throughout much of the Northern hemisphere, would change in very damaging ways.