PROCESSING OF OPTICAL AND RADAR SATELLITE DATA FOR THE DETECTION OF MORPHOMETRIC CHANGES. THE CASE OF THE SAUCE GRANDE RIVER MOUTH (ARGENTINA)

Abstract

This study aims to assess morphometric changes in the mouth of the Sauce Grande river (Argentina) through the processing of optic and radar images. It was made a visual analysis with the high-resolution images during 2011-2018. These images allowed us to identify that the Sauce Grande river's mouth originated a new distributary channel. To detect the occurrence period there were processed Landsat 8 OLI-TIRS and Sentinel 1A and 1B images. It was studied the pluviometric variability during 2018 on a daily time-scale to determine whether the rainfall originated morphometric changes. The distributary channel was evidenced during the period 7th-13th September due to very heavy precipitation events followed by a wet period with heavy precipitation that had an extension of two months. This pluviometric situation is untypical in these regions. The distributary channel was intermittent due to it was observed until November 2018. As a consequence of the rainy condition, optical images did not allow for analyzing the morphometric changes due to the high coverage of clouds. Hence, the method applied is useful for those regions with scarce or non-data and a high-coverage of clouds.