The Implications of Climate Change on Water Resources of Rajasthan

Abstract

Climate change is expected to have a significant impact on the hydrological cycle, which includes precipitation, evapotranspiration, and soil moisture. The most visible sign of climate change is change/increase in temperature. The evapotranspiration or crop water requirement is the most sensitive to temperature changes. Therefore, any temperature change will have a profound effect on the overall crop water requirement and in turn on the water resources of any area. The current study attempts to comprehend the likely impact of climate change on Rajasthan’s water resources. Reference evapotranspiration (ETo) was calculated using the Penman-Monteith equation and the sensitivity of ETo was examined by increasing the temperature from 1% to 3% while keeping other parameters constant. A temperature increase of 1% (≤0.42 °C based on Rajasthan’s normal maximum temperature) will augment the evapotranspiration demand by 11.7 mm on an annual basis. This will further add annual water demand of 718 mcm and 2245 mcm for the whole state based on net irrigated area and total cropped area respectively. The drought-prone region like Rajasthan is not blessed with worthy perennial river systems, so any surge in water demand requires watchful planning for future water resource development.