Connection between sea surface temperature patterns and low level geopotential height in the South Atlantic Ocean

ROLLA, ALFREDO LUIS; GARBARINI, EUGENIA MARÍA; GONZALEZ, MARCELA HEBE

ATMóSFERA

CENTRO CIENCIAS ATMOSFERA UNAM

Lugar: México; Año: 2020 vol. 33 p. 175 - 185

0187-6236

The aim of this work is to study the connection between sea surface temperature in the South Atlantic Ocean and the semi-permanent Anticyclone. In order to do this, sea surface temperature (SST) and geopotential height in 1000hPa (HGT1000) from the reanalysis NCEP/NCAR for the 1981-2016 period were used, with a spatial resolution of 2.5°x2.5° and restricted for the domain 65°W?20°E, 50°S?0° to study the South Atlantic Ocean. Theoretical variability modes of the seasonal anomalies of both variables were calculated using the T mode of the Principal Component Analysis (PCA). In addition, to study the connection between both variables, the linear correlation between the temporal series of the eigenvectors of the different principal components of TSM and HGT1000 was calculated. Results showed that, both in summer and spring, an intensification of the sub polar lows is associated with warmer temperatures in the centre and north regions of the South Atlantic Ocean and cooler to the south. During autumn, a strengthening of sub polar lows southwest of the region is associated with cooler temperatures in the centre of the Atlantic basin, and warmer waters north and south of it. Finally, during winter, positive anomalies of HGT1000 over the argentine coast are associated with cooler temperatures in the centre of the South Atlantic Ocean and warmer over the coasts of both continents.