Impact of climate change on water availability in Bhagirathi River Basin, India

Abstract

The paper aims at simulating streamflow using Hydrologic Engineering Center Hydrological Modelling System (HEC-HMS) under different Representative Concentration Pathways (RCP's) to access the impact of climate change on hydrological regime of Bhagirathi River at Tehri Dam. The input for the study is precipitation and temperature which are obtained from remote-sensing data. The temperature and precipitation data daily products are obtained from Tropical Rain Monitoring Mission (TRMM) and Atmospheric Infrared Sounder (AIRS) missions and the respective future anomalies were obtained from World Bank Climate Change Knowledge Portal (CCKP). The streamflow simulation is done for RCP's 4.5 and 8.5 under the models csiro_mk3_6_0, bcc_csm1_1, ccsm4 and mri_cgcm3. The study found that the combination of remote-sensing data and HEC-HMS model has been successful in simulating streamflow in the region. The region will experience an increase in streamflow discharge under changing climate over the next coming years. The simulation also indicates that there will be a change in temporal distribution pattern of the discharge. Amidst these uncertainties, the predictions also give an insight into the planning and management of constructed or to be constructed hydraulic structures in the basin.