The source: Science everyday
According to one New research published in Nature Climate change, climate-induced seawater warming is slowing deep circulation patterns in the Atlantic and Southern Oceans. The study’s authors, scientists from the University of California, Irvine, analyzed projections from 36 climate models and found that the Atlantic Meridian Circulatory (AMOC) and the Meridian Circulatory South (SMOC) could slow down to 42% by 2100. SMOC could end completely by 2300 in a worse case scenario. “This would be a climate disaster of similar magnitude to the complete melting of land-based ice sheets,” said study co-author J. Keith Moore, UCI’s professor of Earth system science. .
In the Atlantic, as warm water flows north over the surface, it cools and evaporates, making it saltier and denser. This heavier water sinks into the deep ocean and flows south, where it eventually rises again, carrying from the depths the nutrients that are the foundation of marine ecosystems. Over time, according to Moore, disruptions in circulation will cause those nutrients to become trapped in the deep ocean—“leading to a decline in biological productivity in the global ocean.”
In addition, the circulation ensures that carbon dioxide sucked into the ocean is sequestered at depth—what Moore and his colleagues call a “dissolution pump.” There is also a “biological pump” whereby phytoplankton remove carbon dioxide from the atmosphere, and when the animals that consume the phytoplankton die, carbon and nutrients are released at depth. . If ocean circulation is disrupted, both dissolution and biological pumps could be affected—exacerbating global warming.
