Mechanisms of subsurface thermal structure and sea surface thermohaline variabilities in the southwestern tropical Pacific during 1975-85

Major features of the southwestern tropical Pacific (SWTP), defined between 160E-140W and 24S-10S, are brought to light through analysis of surface water samples (23000) and temperature/depth observations (8500), both collected by ship opportunity programs during the 1979-85 period. The mean vertical thermal structure (and its related parameters), mean sea surface temperature (SST) and salinity (SSS) are first portrayed, to further quantify the 1979-85 variability. It is demonstrated that the observed seasonal and interannual variabilities, the latter being associated with the strong 1982-83 El Nino Southern Oscillation (ENSO) event, are mostly governed by specific mechanisms involving varying wind field and rainfall regimes

Observations of the Equatorial intermediate current in the Western Pacific ocean (165°E)

Direct current measurements (0-600 m; re. 600 m) were carried out every six months from January 1984 to June 1986 in the Western Tropical Pacific Ocean (165°E) from 20°S to 10°N. The Equatorial Intermediate Current (EIC) occurred beneath the Equatorial Undercurrent (EUC) in the 300-500 m depth range between 2°S and 2°N. (D'après résumé d'auteur

Proceedings of US - PRC international TOGA symposium

Major features of the South Western Tropical Pacific are brought to light through analysis of sea surface salinity samples (23000) and temperature profiles (8500) gathered to study the 1979-1985 period. It is shown that the surface and subsurface oceanic variability is schematically dominated both by the seasonal cycle and the strong 1982-1983 ENSO signal. Specific mechanisms responsible for the ENSO impact upon a) the vertical thermal structure and its related parameters, b) the sea surface temperature, and c) the sea surface salinity are identified and tested. (Résumé d'auteur