Assessment of climate change impact on hydrological components of Ponnaiyar river basin, Tamil Nadu using CMIP6 models

Abstract This study aims to assess the climate change impacts on hydrological components in Ponnaiyar river basin using Soil Water Assessment Tool (SWAT) model. used 13 Global Climate Models (GCM) from Coupled Model Inter-comparison Project Phase 6 (CMIP6). Based performance evaluation of CMIP6-GCMs, best GCMs selected for future projections were EC-Earth3, MPI-ESM1-2-LR and MPI-ESM1-2-HR. SWAT-CUP (SWAT – Calibration Uncertainty Programs) successfully calibrated validated SWAT The model simulated period under SSP245 SSP585 emission scenarios. results indicated increased streamflow over projected due rainfall basin. annual surface runoff varied −20.41 −15.46%, −10.51 18.34% 73.88 134.56% scenario 2020s, 2050s 2080s, respectively. For water yield −7.02 11.36% −1.41 6.15% SSP585. During there was an increase (7.89–21.18% 36.12–115.25%) could help policymakers stakeholders develop adaptive strategies Ponniyar