A patch of unusually cold water south of Greenland — dubbed the 'cold blob' — is providing new evidence that the Atlantic Meridional Overturning Circulation (AMOC) is weakening, according to research published in Science News. AMOC acts as a planetary conveyor belt, transporting warm water northward and cold water southward, and plays a central role in regulating Northern Hemisphere climate.
What the data shows
Ocean temperature simulations from 1993 to 2021 reveal that the cold blob has cooled relative to the surrounding ocean over the past three decades. This pattern is consistent with computer models predicting AMOC slowdown due to freshwater influx from melting Greenland ice. The research adds to a growing body of evidence that the current system is less stable than previously thought.
What an AMOC collapse would mean
If AMOC were to shut down entirely, the consequences would be severe: Europe could experience rapid cooling of 5-10 degrees Celsius, while tropical monsoon belts could shift, disrupting agriculture for billions of people. Sea levels along the US East Coast could rise by up to a foot beyond global averages. Scientists stress that a full collapse is not imminent but say the risk increases with every fraction of a degree of global warming.