Thomas Haine, John Hopkins University, USA


North Atlantic Impact of Arctic Freshwater Variability?


Large freshwater anomalies clearly exist in the Arctic Ocean. The sources of freshwater to the Arctic from precipitation and runoff have increased in the last few decades while the marine freshwater fluxes draining the Arctic are unchanged. Thus, the balance of sources and sinks of freshwater to the Arctic shifted to freshening during the 2000s. The observed accumulation of liquid freshwater is consistent with this increased supply and the loss of freshwater from sea ice. Discharge of this freshwater may impact the North Atlantic ocean, the Atlantic Meridional Overturning Circulation (AMOC), and hence Atlantic sector climate. AMOC variability can be attributed to other processes, however, and the reasons for observed hydrographic changes in the subpolar North Atlantic and the AMOC remain unclear. I conclude with a discussion of plausible mechanisms and prospects to disentangle them.


Tuesday June 4, 11:15


Rossbysalen C609, Arrhenius laboratory, Svante Arrhenius väg 16C, 6th floor