Here's a Disturbing Theory About Why Climate Change Seemed to 'Pause' for 15 Years

Earth's air conditioning system is called the Atlantic Meridional Overturning Circulation (AMOC). It's a massive, looping current that carries warm water over the sea surface toward the North Atlantic and ferries cold (denser) water south along a deeper undersea route. It's the most important reason that much of Europe — a region much farther north than most population centers in North America or Asia — is warm enough to be comfortably inhabited, and it generally moderates temperatures across the North Atlantic region.  

Researchers have suspected for a long time that the fate of the AMOC might be important to the overall fate of a world subject to rapid climate change.