Transports and Accumulations of Greenland Sea Intermediate Waters in the Norwegian Sea

Abstract

The Greenland Sea intermediate waters transported via the Jan Mayen Channel (JMCh) are a significant source for the Iceland-Scotland Overflow Water. Based on hydrographic data collected by a Norway-China survey in 2015 and Argo floats, we classify the water masses of the Greenland Sea outflow and then reveal their distributions in the Norwegian Sea. The Atlantic-origin water produced by density increase during winter in the northern Greenland Sea was an important component of the intermediate waters exported to the Norwegian Sea, accounting for about 30% of the total volume in 2015. The hydrographic data revealed that the major passage of outflow from the Greenland Sea was located in the southern Mohn Ridge in 2015, rather than in the JMCh, as generally recognized. The transport of intermediate waters from the Greenland Sea via the southern Mohn Ridge in the summer of 2015 is estimated to be about 0.8–1.7 Sv. This transport pattern provides a perspective that there exists a multi-passage system of outflow in the JMCh and Mohn Ridge, promoting a stable supply of intermediate waters to the Norwegian Sea.