AMOC collapse simulations reveal what could happen to the ocean’s carbon

by Rebecca Owen – Phys.org

The Atlantic Meridional Overturning Circulation (AMOC) is the system of currents responsible for shuttling warm water northward and colder, denser water to the south. This “conveyor belt” process helps redistribute heat, nutrients, and carbon around the planet.

During the last ice age, occurring from about 120,000 to 11,500 years ago, millennial-scale disruptions to AMOC correlated with shifts in temperature, atmospheric carbon dioxide (CO₂), and carbon cycling in the ocean—as well as changes in the signatures of carbon isotopes in both the atmosphere and the ocean. At the end of the last ice age, a mass melting of glaciers caused an influx of cold meltwater to flood the northern Atlantic, which may have caused AMOC to weaken or collapse entirely.