Snowmelt runoff prediction under changing climate in the Himalayan cryosphere: A case of Gilgit River Basin

摘要

There are serious concerns of rise in temperatures over snowy and glacierized Himalayan region that may eventually affect future river flows of Indus river system. It is therefore necessary to predict snow and glacier melt runoff to manage future water resource of Upper Indus Basin (UIB). The snowmelt runoff model (SRM) coupled with MODIS remote sensing data was employed in this study to predict daily discharges of Gilgit River in the Karakoram Range. The SRM was calibrated successfully and then simulation was made over four years i.e. 2007, 2008, 2009 and 2010 achieving coefficient of model efficiency of 0.96, 0.86, 0.9 and 0.94 respectively. The scenarios of precipitation and mean temperature developed from regional climate model PRECIS were used in SRM model to predict future flows of Gilgit River. The increase of 3?°C in mean annual temperature by the end of 21th century may result in increase of 35–40% in Gilgit River flows. The expected increase in the surface runoff from the snow and glacier melt demands better water conservation and management for irrigation and hydel-power generation in the Indus basin in future. Graphical abstract Display Omitted Highlights ? Basin hydrology of Gilgit indicated high sensitivity to temperature and precipitation. ? A rise of 1.3?°C in mean annual temperature till 2050 may result in 17% increase in the annual flows of Gilgit River. ? An increase of 3.1?°C in temperature till 2099 may result in 42% increase in the summer flows. ? 1?°C decrease in mean temperature may reduce 3% summer flows of Gilgit River. ? The summer flows would increase by 13% under 10% increase in the cryosphere area of the Gilgit basin.