ACTIVE AND PASSIVE MICROWAVE SYSTEMS IN THE ASSESSMENT OF FLOODED AREA FRACTION AND MEAN WATER LEVEL IN THE PARANÁ RIVER FLOODPLAIN.

SALVIA, MARÍA MERCEDES; GRINGS, FRANCISCO MATIAS; PERNA, PABLO; BARRAZA, VERONICA; KARSZENBAUM HAYDEE; FERRAZZOLI, PAOLO

Ciudad de Córdoba

Congreso; 1° Congreso Argentino de Teledetección; 2012

Over the past decade, several flood monitoring/forecasting methodologies based on remote sensing data have been proposed. Among them, the ones based on microwave observations are the most successful, since large flood events and intense cloud covers are often encountered simultaneously. This is a severe limitation for observations with optical instruments. In a previous work the authors presented a methodology to obtain flooded area fraction as well as floodplain water level using active and passive microwave systems, collected in the same days, and theoretical emission models. First of all, the fraction of inundated area is evaluated by applying a threshold technique to SAR signatures. Then, AMSR-E signatures and the fraction of flooded area derived by SAR are used in order to estimate the polarization difference of the flooded area inside the AMSR-E pixel. Finally, the average water level is estimated by inverting the results of model simulations. In this work, the 2009-2010 ENSO event is analyzed using SAR data from Envisat ASAR, and passive microwave data at X band (~10 GHz) from AMSR-E and Windsat. The estimated water level is compared with in situ water level measurements and an overall error budget that includes several sources of uncertainties is presented.