Critical Atlantic current significantly more likely to collapse than thought

Key Points:

• New research indicates the Atlantic meridional overturning circulation (Amoc) is more likely to collapse than previously thought, with models predicting a 42% to 58% slowdown by 2100, a level nearly certain to lead to collapse.
• The Amoc, vital for transporting warm tropical water to Europe and the Arctic, influences climate and rainfall patterns; its collapse could cause severe cold winters and droughts in Western Europe, shift tropical rainfall belts, and raise Atlantic sea levels by 50-100cm.
• The study combined real-world ocean observations with climate models, reducing uncertainty and showing that pessimistic models forecasting strong Amoc weakening align better with observed data.
• Scientists warn the Amoc slowdown is driven by Arctic warming, which reduces ocean water density and sinking rates, creating a feedback loop that further weakens the circulation.
• Experts emphasize the urgency of avoiding an Amoc collapse due to its potentially catastrophic impacts on global climate, with some fearing the tipping point could be reached by mid-century.