Climate change projection for the marsyangdi river basin, Nepal using statistical downscaling of GCM and its implications in geodisasters

Abstract

There is a very high uncertainty in the future climate change in the Himalayas and few studies has been carried out towards predicting future climate scenario in the Nepal Himalayas. In this study, climate change projection has been carried out for the Marsyangdi River Basin in the Nepal Himalaya which is focused on quantifying impacts of climate change with meteorological parameters (temperature and precipitation) for the future period, based on the outputs from fifth assessment report of Intergovernmental Panel on Climate Change. The study makes use of CanESM2 dataset which are statistically downscaled using statistical downscaling model (SDSM). Climate projections are available for three representative concentration pathways (RCPs) namely RCP 2.6, RCP 4.5 and RCP 8.5 for up to 2100. The study revealed that both the temperature and precipitation will increase for three RCPs in future. Compared to the baseline period, the annual average of maximum temperature has been projected to increase by 0.82 °C, 1.35 °C and 2.29 °C by 2090s, while, annual average of minimum temperature has been projected to increase by 0.87 °C, 1.44 °C and 2.43 °C by 2090s for RCP 2.6, RCP 4.5 and RCP 8.5 respectively. Similarly, annual average precipitation has been projected to increase by 4, 14 and 21 % by 2090s for RCP 2.6, RCP 4.5 and RCP 8.5 respectively. The projected percentage increase in annual precipitation has been found to have inverse relationship with the elevation. The study suggests that climate change is evident in the study area and these findings will be useful in climate change impact assessment in different sectors such as geodisasters and future management strategies in the Marsyangdi River Basin.