Ice-dammed lake outburst flood risk in the plomo basin, central andes (33º s): Perspectives from historical events

Abstract

High mountain regions are extremely sensitive to current climate change affecting natural processes and related hazards (i.e. glacier retreat, slope instability, formation and enlargement of proglacial lakes). Ice-Dammed Lake Outburst Floods (IDLOFs) are highlighted among these phenomena and reach a greater socio-economic impact due to their highly destructive power. Facing on forecasting of more frequency and intensity of dangerous events, risk analysis of communities exposed is required. The purpose of this research was to assess the hazard, vulnerability, and risk against IDLOF in the Plomo and Mendoza valleys in current scenarios. We analyze historical IDLOF events occurred in the Plomo River that was dammed at least three times by surges of the Grande del Nevado del Plomo glacier (GNP) generating six outburst floods in the 1788-2018 period. Almost one century after the most catastrophic event in 1934, many changes in land usage and occupation along the Mendoza valley have occurred, exposing new vulnerable elements to natural hazards in this area. Our findings show a greater risk mainly due to higher vulnerability as a consequence of higher habitat exposition associated with increasing tourist activity and land-use changes. This fact exposes an urgent necessity of land-use planning in Andean regions.