Signature of mesoscale eddies in satellite sea surface salinity data. Issue 2 (21st February 2017) - Melnichenko, Oleg
Abstract: A persistent signature of coherent mesoscale eddies in sea surface salinity (SSS) is revealed by analyzing the relationship between satellite SSS and sea surface height (SSH) variability in an eddy‐following reference frame. Our analysis focuses on mid‐ocean eddies in two representative regions, the southern Indian Ocean and the North Atlantic subtropical gyre. The resulting composite averages reveal a clear signature of mesoscale eddies in satellite SSS with typical SSS anomalies of 0.03–0.05 psu. The spatial structure of eddy‐induced SSS perturbations can be characterized as a superposition of a dipole structure, arising from horizontal advection of the background SSS gradient by eddy velocity field, and a monopole structure related to the eddy core. The observed relationships between SSS and SSH anomalies are used to provide a regional assessment of the role of mesoscale eddies in the ocean freshwater transport in the North Atlantic subtropical gyre. Key Points: Clear and persistent signature of mesoscale eddies in satellite SSS is revealed Westward propagating eddies provide meridional freshwater transport Role of eddies in the ocean freshwater transport can begin to be assessed from existing satellite data