‘Reemergence’ areas of winter sea surface temperature anomalies in the world's oceans

Abstract

Using datasets of sea surface temperature (SST), surface heat flux, upper ocean thermal data, and climatological temperature and salinity profiles, we try to detect ‘reemergence’ areas of winter SST anomalies in the world's oceans, and describe characteristics of these areas in terms of mixed layer depth (MLD), annual mean heat flux and properties of waters formed in winter mixed layer. Eventually, seven reemergence areas are found: four in the Northern Hemisphere and three in the southern Hemisphere. All areas have a large seasonal variation of MLD, and are the regions where annual mean heat fluxes are relatively small except for two regions in the Northern Hemisphere. In the viewpoint of water properties, it is found that these areas correspond to the mode water formation regions: subtropical mode waters of the Indian Ocean, South Pacific, South Atlantic, North Pacific and North Atlantic, and North Pacific central and North Atlantic subpolar mode waters.