CASSIS-MALVINAS: Aviso altimetry and mooring data across the continental slope of Argentina

RAMIRO FERRARI; CAMILA ARTANA; GUILLERMINA PANIAGUA ; MARTIN SARACENO; CHRISTINE PROVOST

Congreso; Ocean Surface Topography Science Team Meeting; 2016

Mooring data were acquired at 3 sites across the continental slope off Argentina around 41°S from December 2014 to December 2015 along Jason satellite ground-track #26 within the CNES-supported CASSIS MALVINAS project (cf poster by Saraceno et al. and Paniagua et al.). We compare altimetry data (AVISO gridded and along- track products) to in situ mooring data using several temporal filters. Different scenarios are observed in 2015. Half of the time the Malvinas Current flows up to 38°S north of the mooring array. This corresponds to the typical situation reported by Vivier and Provost (1999) and Spadone and Provost (2009). Then, the current structure and correlations with altimetry are similar to those previously published.In contrast, the rest of the time, the circulation is totally different with either incoming Brazil Current eddies from the East provoking a blocking of the Malvinas Current (cf Artana et al., 2016) or migrations of the Brazil-Malvinas confluence to the south of the mooring array. This second situation was not observed during previous mooring deployments at the same location. The correlation between altimetry and in situ data decreases during these episodes.We carefully investigate these events using SST (MODIS), MERCATOR operational model outputs (1/12 ) (cf poster by Artana et al.) and a new higher resolution altimetry products (1/8°) from CLS including ciclostrophy and Ekman components (cf poster by Artana et al. and Pujol et al). We are working at describing and understanding the differences in the performance of the various altimetric products in the observed distinct scenarios.