Assessment of water resources and crop yield under future climate scenarios: A case study in a Warangal district of Telangana, India

In the present study, assessment of the impact of climate change on the availability of water resources and crop yield of Warangal district of Telangana state, India has been carried out using Soil and Water Assessment Tool (SWAT). The importance of bias correction methods in regional forecasts with multiple Regional Climate Models (RCMs) along with projected uncertainties have been emphasized, and regionalization of parameters in ungauged watersheds have been dealt with. SWAT model was run using observed data and then calibrated using observed streamflow of Akeru watershed, Warangal district, India. The R-2 and NSE values for calibration (0.72 and 0.84, respectively) and validation periods (0.7 and 0.56, respectively) indicated a significant correlation between observed and simulated streamflow. Then the model was run for historical and future scenarios (early, mid, and end of the 21st century) for four RCMs. Variables such as rainfall, surface runoff, water yield, evapotranspiration, and intensity of rainfall showed an increasing trend under future scenarios, while crop yields (corn, cotton and rice) showed a decreasing trend. The models predicted an increase in the extremity of rainfall events, especially in the months of July and August, for the mid and end of the 21st century. The results showed that the production of cotton is under threat in the district in future. The results obtained can be used to plan the mitigation and adaptation strategies for the region.