Snow runoff modelling in the upper Indus River Basin and its implication to energy water food nexus

• Snowmelt-Runoff Model (SRM) indicated significant increases in annual and seasonal runoff. • RCP4.5 scenario shows stronger seasonal runoff increases compared to RCP8.5, suggesting potential loss of snow and glaciers due to early warming. • Future hydropower capacity projected to increase by 93 % to 167 % under RCP4.5 and RCP8.5 scenarios, respectively. • Construction of multipurpose dams are crucial to mitigate peak flow risks and ensure resilient EWF resources. Pakistan's hydropower sector depends heavily on glacier and snowmelt water that originates from the Upper Indus Basin (UIB). It is expected that climate change may adversely affect future hydropower generation capacity as a result of fluctuations in the magnitude, seasonality and hydrological extremes of the Indus River flow. This study employed the Degree-Day Snowmelt Runoff Model alongside the Moderate Resolution Imaging Spectroradiometer MODIS and daily ground-based hydro-meteorological data to model the snowmelt runoff response in the UIB. The results indicated a significant increase in the annual and seasonal runoff under both RCP4.5 and RCP8.5 scenarios, suggesting more water availability for hydropower and irrigation. By the end of the century, annual river flow is projected to increase by 28 % to 69 % under the RCP4.5 and RCP8.5 climate scenarios. Consequently, rise in annual river flow is expected to increase the electricity generation capacity of future hydropower projects by 93 % to 167 % under the RCP4.5 and RCP8.5 scenarios, respectively. The construction of robust multipurpose dams may potentially reduce flood risks in downstream areas during peak flows, while also supplying water for hydropower generation and irrigation during low flows. This, in turn, may enhance the resilience of both the hydropower and agriculture sectors in the face of climate change.