Potential changes in Korean water resources estimated by high-resolution climate simulation

Because climate change does not occur uniformly throughout the globe, climate change is expected to impact each region differently. Undertaking the first national-level climate impact assessment in Korea, we evaluated the impacts of climate change on Korea's 139 drainage sub-basins, that have varying climate and complex topography. Subsequently, we estimated the spatial and temporal variations of water resources in each sub-basin under a climate change simulation. This simulation was based on high-resolution data (27 x 27 km) that were created by the Korean Meteorological Research Institute using the climate models ECHO-G and NCAR/MM5. In order to generate the climate and runoff simulations for each sub-basin, we used the LARS-WG model, a stochastic weather generator, and the PRMS hydrologic model. The results indicated that the amount of runoff was expected to decrease in spring and summer and to increase in fall and winter. Runoff amounts were also expected to increase in northern regions and decrease in southern regions. In addition, relative changes in water balance components-precipitation, evapotranspiration, and runoff-are investigated. These variations in the timing and amount of runoff under climate change could have significant implications for the sustainable management of water resources in Korea.