For two decades, the Atlantic meridional overturning circulation (AMOC) or “great ocean conveyor” has been measured at 26°N in the Atlantic.  The AMOC is responsible for redistributing heat and freshwater in the Atlantic, and is associated with climate impacts like drought in the Sahel and changes in hurricane intensity and frequency.  What do we know about AMOC variability from in situ observations?  What is there left to learn?  I will review some of the ways in which the AMOC affects climate, what we’ve learned from observations (including challenges with making consistent, large-scale observations spanning an entire ocean basin) and finish with some recent progress into understanding how the AMOC behaves as a coherent entity (or not) and what we are learning about the ocean circulation’s response to high-latitude forcing.

Ocean conveyor,Overturning circulation,Large-scale observations