Measuring ocean circulation in the North Atlantic



The Atlantic Meridional Overturning Circulation (AMOC), which carries warm water from the tropics to northern latitudes and brings dense, cold water back southward, is a major conveyer of heat and an important element of the climate system. Some scientists have worried that AMOC may slow down as Earth's climate warms, but more measurements of the current state of ocean circulation are needed to fully understand AMOC dynamics. Using yearly hydrographic measurements in the North Atlantic at 59.5°N latitude and satellite altimetry data from 2002 through 2008, Sarafanov et al. assessed the mean state of the summer circulation in between Cape Farewell in Greenland and the Greenland-Scotland ridge and quantified transports in the upper ocean, middepth, and deep currents. The measurements contribute to the understanding of ocean circulation dynamics in the northern North Atlantic and provide a benchmark for numerical models. (Journal of Geophysical Research-Oceans, doi:10.1029/2011JC007572, 2012)