Oceanography The Official Magazine of
The Oceanography Society
Volume 28 Issue 01

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Volume 28, No. 1
Pages 106 - 113


Variability and Interleaving of Upper-Ocean Water Masses Surrounding the North Atlantic Salinity Maximum

Andrey Y. Shcherbina Eric A. D’Asaro Stephen C. Riser William S. Kessler
Article Abstract

The North Atlantic subtropical salinity maximum harbors the saltiest surface waters of the open world ocean. Subduction of these waters gives rise to Subtropical Underwater, spreading the high-salinity signature over the entire basin. The Salinity Processes in the Upper-ocean Regional Study (SPURS) is aimed at understanding the physics controlling the thermohaline structure in the salinity maximum region. A combination of moored and autonomous float observations is used here to describe the vertical water mass interleaving in the area. Seasonal intensification of interleaving in late spring and the abundance of small-scale thermohaline intrusions point to an important role for submesoscale processes in the initial subduction and subsequent evolution of Subtropical Underwater.


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