Modeling runoff responses to 1.5 °C and 2 °C rise in temperature in snow-fed basin of western Himalayas

Snowmelt Runoff Model (SRM) was employed to study the impact of climate change on the hydrology of the Sindh basin. The model was calibrated for the year 2010 and validated for the years 2011–2016. Daily discharge of the river was predicted under four possible climate change scenarios, Scenario I (T + 2 °C and P + 10%), Scenario II (T + 1.5 °C, P-10%), Scenario III (T + 2 °C, P + 10%) and Scenario IV (T + 1.5 °C, P-10%). Snow covered area (SCA) was calculated from an 8-day composite Moderate Resolution Imaging Spectroradiometer (MODIS) data product (MOD10A2). The SCA reduced from approximately 90% in January to around 20% in September. The model predicted an increase of 59% in daily runoff during the late Spring and early summer season under scenario III, 45% under Scenario I, 29% under Scenario IV, and 17% under scenario II climatic conditions. The model performance was assessed using volume difference (Dv) and Nash–Sutcliffe coefficient of determination (R²). The model accuracy was satisfactory as the estimated and observed discharge matched precisely with an overall Dv of − 4.9% and the R² remained above 0.9 for the simulation period. The peak discharge month shifted from August in 2010 to May in the simulated scenarios. A significant decrease has been observed in the river discharge in Autumn under the various climate change scenarios. The results of the study point toward an increase in the frequency and magnitude of the floods in peak snowmelt season while drought-like conditions would occur in the lean season.