IMPACT OF SEA LEVEL RISE ON JAPANESE COASTAL AREAS AND ECONOMIC ASSESSMENT VIA SHARED SOCIOECONOMIC PATHWAYS

Abstract

 Sea level rise (SLR) due to climate change poses a serious threat to human populations in coastal areas. This study evaluated the impact of SLR and astronomical tides in coastal Japanese prefectures, and assessed factors such as the potential inundated area, affected populations, and economic damage. Utilizing the latest climate scenarios, tidal data, and socioeconomic scenarios (SSP), sea level rise and inundation effects in the coastal areas of Japan were evaluated with a resolution of 1 km. Based on the results, the potential inundated area of Japan’s landmass was determined to be from about 2,127 km² in 2050 to about 2,598 km² in 2100, under the Representative Concentration Pathway 8.5 (RCP 8.5) scenario. The affected population was estimated to be 4.61-5.51 million in 2050 and 2.53-5.65 million in 2100, depending on the scenario given by each of the five SSPs. The economic damage was also estimated under SSP1-5, and was determined to vary from 40-64 billion US dollars in 2050 to 58-185 billion US dollars in 2100. In addition, specific features of prefectures such as populated urban coastal areas and terrain conditions were also discussed.