Infamous disaster scenario can rapidly unfold, study finds

Key Points:

• A new study published on April 29 reveals that the Atlantic Meridional Overturning Circulation (AMOC), a critical ocean current influencing global climate, has rapidly changed in the past due to violent volcanic eruptions that cooled the planet.
• The AMOC is a key oceanic conveyor belt that moves warm, salty water from the tropics to the North Atlantic, affecting weather patterns and keeping northern Europe warmer while cooling parts of North America.
• Research indicates that during the Younger Dryas period (about 12,900 to 11,700 years ago), a cluster of volcanic eruptions disrupted the AMOC, causing a significant cooling in the Northern Hemisphere and forcing early humans to adapt to colder conditions.
• Unlike past volcanic causes, the current threat to the AMOC is from human-caused excess carbon dioxide, which may weaken or collapse the current, potentially impacting climate and weather for hundreds of millions of people.
• This study strengthens the theory linking volcanic activity to past AMOC disruptions by using geochemical evidence from North American sedimentary and ice core records, highlighting the AMOC's sensitivity to climate disturbances.