Temporal and Spatial analysis in the Southwestern Atlantic

LAURA RUIZ ETCHEVERRY, MARTÍN SARACENO AND ALBERTO PIOLA

Buenos Aires

Congreso; XXXI Scientific Committe on Antarctic Research (SCAR); 2010

We characterize the length scales of the spatio/temporal variability of the surface currents in the Southwestern Atlantic (SWA) using (i) gridded Sea Surface Heights (SSH) with a 1/3 of degree spatial resolution ii) 4-km resolution satellite derived sea surface temperature (SST) , and (iii) a 6 month time-series of in-situ current data collected at 57,003 ºW – 41,987 ºS. Quantifying the dominant spatial scales of patterns in high resolution SST will assist interpretation of the in-situ moored data and of low resolution satellite data. Comparison between geostrophic velocities computed from satellite altimetry and the current meter data suggests that at this location only time scales longer than 35 days can be estimated from altimetry data. Robust statistics of two-dimensional SST autocorrelation shows an organized pattern with high values over the Malvinas Current and relatively low values in the recirculation region of the Brazil Current, indicating low and a high degree of spatial variability, respectively. The SST analysis also shows a region of high standard deviation values in the region where the current meter was moored, which suggests an enhanced exchange of waters across the shelf-break.