Variation of the Cromwell Current Southern Extension off Peru between 3 and 14° S

Abstract

Flores R, Tenorio J, Domínguez N. 2009. Variation of the Cromwell Current Southern Extension off Peru between 3 and
14o
S. Bol Inst Mar Perú XXIV (1-2): 39-52.- The variations of the Cromwell Current Southern Extension (CCSE),
between 3 and 14°S, within 60 mn, are described based on geostrophic calculations. The time series of the mean
depth of the 15 o
C isotherm (1961-2005) and of the mean dissolved oxygen values (1980-2005) are presented. The
geostrophic flow toward the south, calculated in the sections off Paita, Punta Falsa, Chicama, Chimbote, Callao,
Pisco and San Juan up to 200 mn, showed changes mainly during the summer and autumn seasons concerning
latitudinal extension and deepening. The time series of mean depth of the 15 o
C isotherm, along the coast,
showed the biggest depth in January and May-June, being shallower in October-November. Oxygen ranges of
2.0-0.5 mL/L showed a strong correlation with the CCSE for depths between 90 to 180 m in northern Peru (3-8o
S)
where the bottom trawl fishery takes place.