Human-caused warming has led to an “almost complete loss of stability” in the system that drives Atlantic Ocean currents, a new study has found – raising the worrying prospect that this critical aquatic “conveyor belt” could be close to collapse.

In recent yearsscientists have warned about a weakening of the Atlantic Meridional Overturning Circulation (AMOC), which transports warm, salty water from the tropics to northern Europe and then sends colder water back south along the ocean floor. Researchers who study ancient climate change have also uncovered evidence that the AMOC can turn off abruptly, causing wild temperature swings and other dramatic shifts in global weather systems.

AMOC is running out of steam, making it more susceptible to disruptions that might knock it out of equilibrium, said study author Niklas Boers, a researcher at the Potsdam Institute for Climate Impact Research in Germany.

If the circulation shuts down, it could bring extreme cold to Europe and parts of North America, raise sea levels along the U.S. East Coast and disrupt seasonal monsoons that provide water to much of the world.

If the AMOC does completely shut down, the change would be irreversible in human lifetimes. “It’s one of those events that should not happen, and we should try all that we can to reduce greenhouse gas emissions as quickly as possible,” Boers said. “This is a system we don’t want to mess with.”

Source: The Washington Post

Photo: Salwan Georges/The Washington Post