Estimation of Deglaciation in the Quillcay River Sub-Basin-Peru, in the Face of Climate Change

Abstract

In recent decades, glaciers globally and mainly tropical glaciers have experienced an accelerated retreat of snow cover due to climate change. In the tropical glaciers of Peru, this has generated the development of numerous gaps and an increase in their volume over the years. In the present research, a methodology with new improved indexes is proposed: Normalized Differential Snow Index without water information (NDSInw) and Normalized Differential Water Index without snow information (NDWIns). The changes occurred are identified through a multitemporal analysis of the snow surface in the Quillcay river sub-basin during 1986 to 2021 using satellite images of Landsat 5, 8 and 9 collection 2 of the Google Earth Engine (GEE) data catalog and processing the spatial data using the API (Application Programming Interface) from rgee. The results obtained from the deglaciation of the snow-capped mountains in the 35 years of analysis resulted in a decrease of 27.82% with respect to 1986. The projection of the glacier coverage estimate was made using the linear regression method where the R2 is 0.9614, it was carried out until the year 2056 and the glacier coverage trend is to decrease its volume by 69.5% with respect to the year 1986.