Scientists warn that a crucial ocean current could collapse, altering global weather

by HAYLEY SMITH at latimes.com

Scientists are sounding the alarm that a crucial component of the planet’s climate system is in gradual decline and could one day reach a tipping point that would radically alter global weather patterns.

The Atlantic Meridional Overturning Circulation, or AMOC, is a system of ocean currents that circulate water in the Atlantic Ocean like a conveyor belt, helping to redistribute heat and regulate global and regional climates. New research, however, warns that the AMOC is weakening under a warming climate, and could potentially suffer a dangerous and abrupt collapse with worldwide consequences.

“This is bad news for the climate system and humanity,” researchers from Utrecht University’s Institute for Marine and Atmospheric Research wrote in a new study published in the journal Science Advances.

Considering the AMOC is the workhorse of the Atlantic, the consequences of such a collapse would result in “hugely chaotic changes in global weather patterns” that extend far beyond the Atlantic, said Daniel Swain, a climate scientist with UCLA who was not involved in the study.

“It would plunge Europe into essentially a regionalized Ice Age, while leaving the rest of the world on its continued warming path,” Swain said. “The Southern Hemisphere would roast, the Pacific storm track would go kind of nuts, and there would be these extreme shifts in weather patterns that are very different from what you would expect from a more incremental or linear warming path.”

The odds of such a collapse are low — about 5% or 10% this century, according to some researchers — but the consequences are so great that it would be unwise to ignore the possibility, Swain said.