Impact of Climate Change on Flood Discharge and Flood Stage in the River Basin

In recent years, extreme weather events due to climate change have frequently occurred over the world. Meanwhile, the Korean peninsula has suffered from natural disasters such as floods and droughts. Especially in Korea, the flood damage tends to be increasing rapidly. Therefore, it is necessary to estimate the flood discharge and flood stage under climate change for the purpose of reducing flood damage. This study is to assess the impact of climate change on flood discharge and flood stage in Sumjin river basin, Korea. Sumjin, Yochun, and Bosung rivers are selected for this study, and these are the areas in which the model is constructed and applied. SRES A1B climate change scenarios, provided by the IPCC for the simulation of future climate data, were applied for the four different targets periods (Target I : 1971~2010, Target II : 2011~2040, Target III : 2041~2070, Target IV : 2071~2100), and HEC-GeoHMS and HEC-HMS models are used to estimate flood discharge for each target period. Then HEC-RAS model is served for investigating the variation of flood stage due to the climate change at Songjung station, which is located in the basin outlet. The results are compared with the previous studies in which climate change was not considered. Those results could be used as the basic information for the future disaster prevention planning under climate change.