Projection of the Tidal Component in Tidal River Stage Using SSP Scenarios

Recently, sea level is rising globally through sea ice thawing and thermal expansion caused by climate change. In the case of Korea, the sea level in 2020 increased by 9.1cm compared to 1989 and it is effecting tidal rivers located in the coastal areas. Unlikely to general rivers, tidal rivers have complex hydrological characteristics due to the influence of not only rainfall but also tides of a river estuary. Therefore, the analysis of the tidal level should be preceded in the change of the river stage. In this study, the tide level was projected by using SSP(Shared Socioeconomic Pathways) scenarios and the tide component affecting the Taehwa River stage was projected. For climate change scenarios, SSP5-8.5 and SSP2-4.5 were used, and GCMs(General Circulation Models) data related to sea level height were selected as independent variables such as sea water volume, sea ice area fraction, etc to apply spatial downscaling using artificial intelligence. As a result the tidal component of the Taehwa River was projected to rise by 21cm in the SSP2-4.5 scenario and 28cm in the SSP5-8.5 scenario. Through this study, it was possible to identify an increase in the risk of flooding in coastal areas near tidal rivers, and it can be helpful in establishing the design standards for disaster prevention facilities to reduce the damage caused by rising tides.