Convergence of the Brazil Current and the Malvinas/Falkland Current
[Hat-tip to Amato Evan at CIMSS for pointing out this very interesting AVHRR sea surface temperature imagery] AVHRR sea surface temperature (SST) data (above, viewed using Google Earth) revealed the striking convergence of the Brazil Current and the Malvinas/Falkland Current off the east coast of South America on 07 April 2008. The Brazil Current transports warm subtropical water (SST values of 22º to 28ºC, yellow to orange colors) southward, while the Malvinas/Falkland Current transports cold Antarctic water (SST values of 6º to 12ºC, cyan to dark blue colors) northward. These two ocean currents are seen to converge several hundred kilometers off the coast of Argentina — the exact location of this Brazil/Malvinas convergence zone changes with the seasons.
An animation of daily AVHRR SST images from 01 to 07 April (below) shows subtle variations in the position of the Brazil and Malvinas ocean currents, as well as interesting eddy structures in the vicinity of the Brazil-Malvinas Confluence. Note the appearance of a well-defined “comma cloud” associated with a strong cyclone off the coast on 06 April (recall that winds flow clockwise around a cyclone in the Southern Hemisphere).
The colder waters of the Malvinas Current are rich in nutrients which support the growth of marine plant life, which then attracts large numbers of fish to feed — therefore, the commercial fishing industry is very interested in satellite data that accurately depict the location of such cold ocean currents.
Reference: Convergence Zones – Where the Action Is (NASA Goddard Space Flight Center)