The North Atlantic Ocean is in a state of reduced overturning

Date: 
Friday, 1 December, 2017 - 14:00 to 15:00
Location: 
NOC Southampton - Henry Charnock Lecture Theatre (Waterfront Campus).
Speaker: 
David Smeed, National Oceanography Centre

The North Atlantic Ocean is in a state of reduced overturning

Throughout the world the oceans and atmosphere transport heat from the equatorial regions towards the poles with one remarkable exception that is the South Atlantic Ocean. A consequence of the equatorward movement of heat in the South Atlantic is a large poleward heat transport in the North Atlantic carried by the Atlantic Meridional Overturning Circulation (AMOC). Variability of the AMOC is believed to be a primary mechanism in decadal changes of the North Atlantic surface temperatures which have in turn been implicated with a number of important climate impacts such as rainfall in the African Sahel, the frequency of hurricanes and European weather.  The RAPID 26°N array has been measuring the AMOC since 2004.    During the period of observation there has been a significant reduction in the AMOC.   The change in state of the AMOC is concurrent with other changes in the North Atlantic such as a broadening and weakening of the Gulf Stream, and an altered pattern of sea-surface temperature (SST). These changes resemble the response to a declining AMOC predicted by coupled climate models.  The observations provide strong  evidence  that the AMOC is a major factor in decadal scale variability of North Atlantic climate. 

Seminar category: 
Friday seminars