A new study reveals that the Atlantic Meridional Overturning Circulation (AMOC), a crucial component of Earth’s climate system, is more likely to collapse than previously thought. Scientists found that the climate models predicting the greatest slowdown are the most accurate, raising concerns about the potential consequences for Europe, Africa, and the Americas.
AMOC, already at its weakest in 1,600 years due to climate change, shows signs of nearing a tipping point. While past models varied widely in projections—ranging from no slowdown to a 65% reduction by 2100—the latest study estimates a slowdown of 42% to 58% by 2100, which would significantly increase the risk of collapse.
A collapse would shift the tropical rain belt crucial for agriculture, lead to severe winters and droughts in Western Europe, and elevate sea levels by 50 to 100 centimeters. Dr. Valentin Portman, who led the study, noted that these findings suggest AMOC is declining more than expected, approaching a tipping point. Professor Stefan Rahmstorf emphasized the urgent need to avoid collapse, cautioning that the risk of AMOC shutting down has risen to over 50%.
The slowdown is driven by rapidly rising Arctic temperatures, leading to less dense water that sinks more slowly, thus creating a feedback loop. The complexity of AMOC makes predictions challenging, but the study’s refined model, using real-world data, suggests even greater weakening could occur, especially with unaccounted factors like Greenland’s meltwater.
Published in Science Advances, the research points to the urgent need for action to mitigate climate impacts associated with a potential AMOC collapse.
