Seasonal and Interannual Variability of Biophysical Submesoscale Fronts in the South Atlantic Ocean

Wednesday, 17 December 2014
Marouan Bouali, Olga T Sato and Paulo S Polito, Instituto Oceanográfico da Universidade de São Paulo, Sao Paulo, Brazil
Ocean structures like filaments, eddies and spirals visible at spatial scales of the order of ~1 km are now known to play a significant role in ocean-atmosphere interactions. Therefore, observation and modelling of ocean submesoscale processes as well as their long term changes have become a major research area in oceanography.
In this study, a 12 years (2002-2014) satellite dataset of level 2 Sea Surface Temperature (SST) and Chlorophyll-a concentration (CHL) derived from NASA's MODIS instrument onboard Terra and Aqua platforms was processed for stripe noise reduction and improved cloud masking to produce a climatology of submesoscale fronts in the South Atlantic Ocean. Instantaneous images of SST and CHL gradient magnitude were binned into seasonal and annual composite maps to 1) identify regions with intense biophysical frontal activity 2) quantify long term trends of SST and CHL submesoscale fronts from 2002-2014 and 3) investigate the spatio-temporal correlation between thermal and biological ocean processes.