Projected drought risk assessment from water balance perspectives in a changing climate

In the face of changing water environment due to climate change, the assessment of water demand and water supply capacity by region is needed to prevent and mitigate droughts. Herein, we propose a quantitative approach to identify high drought risk areas in South Korea by applying future climate and socio‐economic change scenarios to calculate the demand and supply of municipal, agricultural, and industrial water. Three Coupled Model Intercomparison Project 5 Global Climate Models were selected to assess future drought risk under different climate change scenarios by combining meteorological and socio‐economic factors. The drought hazard was assessed by calculating the severity and frequency of drought based on a rating method. Drought vulnerability was assessed by calculating water shortages in domestic, industrial, and agricultural waters based on water demand and supply capacity and applying entropy weightings. According to future climate change scenarios, the Youngsan River Basin was more vulnerable to drought than other basins. The results of the IPSL‐CM5‐LR model also suggest that the drought risk in the Youngsan River Basin will increase during the period 2071–2099. By demonstrating the relative sensitivity of drought risk on the Korean Peninsula to various future emission scenarios, our work provides valuable information to update mid‐ to long‐term drought mitigation strategies. This study provides a detailed assessment of future drought risk in South Korea based on future climate projections and socio‐economic scenarios affecting water demand up to 2099. We have developed a novel approach that accounts for both drought risk and drought vulnerability in the assessment of overall hazard. We categorize levels of risk based on projected changes in precipitation and the supply and demand of domestic, industrial, and agricultural water. Percentile changes in DRI for S1 (2011–2040), S2 (2041–2070), and S3 (2071–2099) under RCP 4.5 and 8.5 emission scenarios. For each panel, red (blue) indicates an increase (decrease) in drought risk compared to S0 (1976–2005) as a baseline.