Delineation of agricultural drought-prone zones considering irrigation capacities of agricultural facilities under climate change

This study was conducted to delineate agricultural drought-prone zones with respect to each agricultural watershed in South Korea, considering irrigation capacity of agricultural facilities under the representative concentration pathways (RCPs) as the latest generation of climate change scenario. Simulated temporal and spatial data (2011–2100) on precipitation and temperature for two RCPs, high-level greenhouse gases emission scenario (RCP 8.5) and intermediate-level one (RCP 4.5) were applied to the standardized precipitation index (SPI) in order to project meteorological drought periods in the twenty-first century. With consideration of irrigation capacity of agricultural facilities on the each watershed, non-beneficial areas on irrigation were designated to be agricultural drought-prone zones during the projected drought periods. One representative watershed was selected to identify the applicability of the delineating method. Results of the SPI simulation exhibited five separate drought periods (2020s, mid-2030s, mid-2040s, 2050s, and 2080s) during the twenty-first century on this watershed. During the projected drought periods, 22 administrative towns (73%) among 30 towns in this watershed would turn out to be continuously irrigated by 61 agricultural facilities enduring 10-year cycle meteorological drought. Remaining 8 towns (27%) would be vulnerable to droughts due to lack of irrigation water. The standardized groundwater level index exhibited groundwater aquifer has an irrigation capacity on the farm fields during long-term drought periods.