has part composed primarily of mesoscale marine eddy field marine mesoscale eddy field A mesoscale eddy field is an expanse of marine water which includes coherent vortices, as well as a rich cascade of other structures such as filaments, squirts and spirals and is characterized by temperature and salinity anomalies with associated flow anomalies that are nearly in geostrophic balance. Although only the surface expression of mesoscale eddies is visible in satellite images of sea surface height or temperature, they are in fact three dimensional structures that reach down into the pycnocline. ORCID:0000-0002-4366-3088