Eddy detection in the Brazil/Malvinas Confluence region

SARACENO, M.; PIOLA, A. R.

Workshop; SAMOC 3; 2010

UCAR

The Brazil/Malvinas Confluence region plays a major role in the South AtlanticMeridional Overturning Circulation (SAMOC) since it is a crossroad of waters withdifferent origins and properties such as the North Atlantic Deep Water and the AntarcticIntermediate Waters. The stirring associated with the Brazil/Malvinas Confluenceconstitutes an important factor setting the characteristics of global deep water masses andtherefore plays an important role in global climate variability. Yet the spatio/temporalvariability associated to the Confluence is not well known. One of the factors thatcontribute to the mixing of the waters is the formation and fate of eddies. In the presentstudy, an objective methodology is applied to detect and follow the eddies in theConfluence region using a database of 16 years of remote sensed Sea Surface Height(SSH) images. Preliminary results suggest seasonal and interannual variability in thenumber of eddies: it is found that there is a higher number of eddies in winter than insummer and that the number of eddies decrease considerably in 2001. Links betweenthese observations and the spatio/temporal variability of other major phenomena presentsin the Western South Atlantic are discussed.