ASSESSING THE MEGADROUGHT IN PROVINCE OF CACHOPOAL, CHILE, USING MODIS PRODUCTS

Abstract

The mega-drought affecting the province of Cachapoal, in Libertador General Bernardo O'Higgins Region, Chile, was assessed by mapping the temporal change magnitude of NDVI (normalized difference index) and LST (land surface temperature) variables, retrieved from MODIS (Moderate Resolution Imaging Spectroradiometer)/Terra composite products in quinquennia of the last 20 years. For this purpose, the current values (within a period bounded to mid-summer of 2021) of both variables were compared in accordance to their quinquennial equivalents between 2001 and 2016 and normalized regarding their temporal variability. Results indicate significant relative NDVI relative decreases, as well as significant LST relative increases, involving not only land uses located in the valley but in the mountain as well. These could be attributed to the water shortage advocated by the mega-drought. It is expected this study may orientate further planning and environmental managing actions regarding the mega-drought in the Province, in pursuit of replicate it in other geographical ranges of the Chilean territory.