Suscetibilidade à inundação de lagos glaciais na sub-bacia Chajolpaya, norte da Cordilheira Real, Bolívia

Susceptibility to Glacial Lake Outburst Flood in the Chajolpaya subbasin, northern Cordillera Real, Bolivia

Abstract

Most of the glaciers across the planet have been retreating in recent decades as a response to global climate change. The loss of glacier area in all regions of the world over the 20th and 21st centuries has resulted in an increase in glacial lakes. The aim of this study was to investigate the flood susceptibility associated with glacial lakes fed by tropical glaciers, located in a pilot study area of the Chajolpaya sub-basin, in the north of the Cordillera Real, Bolivia, using the AHP methodology - Weighted Hierarchical Analysis, with aid of remote sensing and geoprocessing tools. Satellite images were used, referring to the years 1999, 2011, 2015 and 2022, from which 16 glacial lakes in the study area were selected, according to established criteria, to be analyzed and monitored. The results found indicated that two lakes have very high susceptibility to flooding (GLOF - Glacial Lake Outburst Flood), four lakes have high susceptibility to GLOF, six lakes have medium susceptibility, no lake has low susceptibility and four have very low susceptibility to GLOF. These results indicate the existence of cryospheric risks associated with very high and high risk lakes, which can impact downstream communities.