INFLUENCE OF OCEAN COLOR DATA REPROCESSINGS ON SATELLITE-DERIVED CHLOROPHYLL CONCENTRATIONS IN THE PATAGONIA ARGENTINEAN SEA

ANGEL-BENAVIDES, I.M.; GARCIA, C.A.E.; DOGLIOTTI, A. I.

alt Lake City

Congreso; ASLO/AGU 2012 Ocean Sciences Meeting; 2012

A complete reprocessing of the entire satellite ocean color images is performed by OBPG-NASA when significant changes are made in algorithms, in processing schemes, etc. OBPG-NASA also performs a global scale validation and comparison of ocean color products after every reprocessing. In this work, we compared three distinct datasets: in situ, SeaWiFS and MODIS/Aqua satellite-derived chlorophyll data in the Patagonia Argentinean Sea, for two successive reprocessings (R2007 and R2009). Reports based on R2007 have pointed that SeaWiFS satellite data tends to overestimate chlorophyll concentration in zones of high pigment concentration in global scale. In R2007, the differences between SeaWiFS and MODIS/Aqua chlorophyll were dependent on concentration, with higher SeaWiFS(MODIS/Aqua) values at low (high) pigment concentrations in Patagonian waters. Validation based on R2009, showed that SeaWiFS and MODIS/Aqua sensors underestimated in situ chlorophyll for concentrations above 1 mg.m-3. Moreover, in R2009, the satellite-derived differences were independent on concentration, with higher MODIS/Aqua than SeaWiFS chlorophyll values. Therefore, changes in the differences between satellite/satellite and satellite/in situ chlorophyll concentrations caused by different reprocessing have also to be assessed at regional scales.