The Southern Ocean: How does this body of water and its relationship with clouds contribute to the world’s changing climate?
Located at the southernmost end of Earth, the Southern Ocean surrounds Antarctica like a gigantic ring. Its currents flow around the continent in enormous spirals, pushing large amounts of cold water into the other oceans. Despite being remote, the Southern Ocean has an impact on the other oceans and their cloud cover, with effects even in distant tropical locations. Therefore, it is of importance for climate projections.
Between 1979 and 2013, the Southern Ocean surface cooled substantially in observations, and the tropical Pacific has been cooling particularly in the eastern basin at the same time. Both happened despite global warming. However, current coupled climate models fail to simulate the observed pattern and its associated anomalous enhanced tropical cloud cover during that period, which acted like a sunscreen to slow down global warming.
While the Southern Ocean cooling is often attributed to a La Niña–like Pacific sea surface temperature trend, the authors propose an alternative hypothesis in their study: that the observed Southern Ocean cooling may have partially contributed to more negative global climate feedbacks. That means that the cooling of the Southern Ocean sparked a favorable chain of events that lessened the severity of warming due to climate change.
The study is published in the journal Nature Geoscience.
2023-08-24 10:48:03
Source from phys.org