Modelling Snowmelt Runoff from Tropical Andean Glaciers under Climate Change Scenarios in the Santa River Sub-Basin (Peru)

Elmer Calizaya,Fernando Corroto,Efrain Turpo,Abel Mejía,Fredy Calizaya,Elgar Barboza,Rolando Salas,Héctor Vásquez

doi:10.3390/w13243535

Abstract

Effects of climate change have led to a reduction in precipitation and an increase in temperature across several areas of the world. This has resulted in a sharp decline of glaciers and an increase in surface runoff in watersheds due to snowmelt. This situation requires a better understanding to improve the management of water resources in settled areas downstream of glaciers. In this study, the snowmelt runoff model (SRM) was applied in combination with snow-covered area information (SCA), precipitation, and temperature climatic data to model snowmelt runoff in the Santa River sub-basin (Peru). The procedure consisted of calibrating and validating the SRM model for 2005–2009 using the SRTM digital elevation model (DEM), observed temperature, precipitation and SAC data. Then, the SRM was applied to project future runoff in the sub-basin under the climate change scenarios RCP 4.5 and RCP 8.5. SRM patterns show consistent results; runoff decreases in the summer months and increases the rest of the year. The runoff projection under climate change scenarios shows a substantial increase from January to May, reporting the highest increases in March and April, and the lowest records from June to August. The SRM demonstrated consistent projections for the simulation of historical flows in tropical Andean glaciers.

Highlights

Global temperature has increased 0.89 ◦ C since 1901, which has negatively affected the spatial and temporal patterns of precipitation [1]
The snowmelt runoff model (SRM) was used to simulate the runoff of the Santa River sub-basin during the reference period 2005–2009, using the snow cover product MOD10A1 and climatic data of temperature and precipitation
The results show a substantial increase in runoff projected for January to May

Summary

Introduction

Global temperature has increased 0.89 ◦ C since 1901, which has negatively affected the spatial and temporal patterns of precipitation [1]. Global warming is expected to affect river flow and increase the melting of glaciers in the coldest parts [2,3]. Ninety-nine percent of the planet’s tropical glaciers are located in the South American Andes [4]. These glaciers are the natural water storage for downstream populations in high mountain watersheds [5]. Glacier melting affects human populations, changes the hydrological cycle, increases sea level and natural hazards [6]. Besides being an important cause of the change in glacier morphology, it can provide basic parameters for assessing water resources [7]

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Discussion

Conclusion