One of Earth’s Largest Ocean Circulation Systems Slows to Unprecedented Rates

Nature Geoscience, February 25

After a long and relatively stable period, one of Earth’s largest ocean circulation systems — the Atlantic Meridional Overturning Circulation (AMOC) —started weakening during the early 19th century; followed by a second, more rapid, decline in the mid-20th century. Over the past few months, according to this study the AMOC has been weaker than we have ever seen in at least the past 1,000 years; but this finding is not entirely accepted by some researchers. These Atlantic Ocean currents redistribute heat across our planet and have a major impact on Northern Hemisphere weather. Authors emphasize that improved understanding of this slowdown is desperately needed, especially regarding the importance of specific components and pathways of the AMOC and how these have changed.

Note: The New York Times published an excellent, extensive animation of the AMOC and this study earlier this week; see:

Compiled by Amy Imdieke.