RELATIONSHIP BETWEEN SEA SURFACE TEMPERATURE AND OCEANIC MIXED LAYER ON THE PASSAGE OF EXTRATROPICAL CYCLONES AT THE SOUTHWEST ATLANTIC

The importance of the oceanic mixed layer (OML) variation on the sea surface temperature (SST), under the influence of atmospheric extratropical cyclones was investigated in this paper. An OML simplified model derived from HYCOM (Hybrid Coordinate Ocean Model) model, based on Kraus and Turner model, was inserted as a subroutine on the BRAMS (Brazilian Regional Atmospheric Modelling System), to update the TSM every time step in the atmospheric model. The OML-BRAMS was characterized by narrowing during the trajectories of low pressure, but has not indicated a significant deepening following the anticyclone rear frontal system. The SST calculated by the BRAMS OML showed large variations (1.0°C-5.0°C) at the initial times. However, as soon as SST has been adjusted, few variation over time occurs (1.0°C-2.5°C), with the deepening (narrowing) of OML associated with decreasing (creasing) temperature.

Oceanic mixed layer; SST; South Atlantic cyclone; Numerical modeling; BRAMS; HYCOM.