LAUSR

Abstract In this study, we evaluate the effect of climate change on explosive cyclones (ECs) using mega-ensemble projection data (d4PDF), which has 50 members of 60-years present climate experiments and 90 members of 60-years +4K future climate experiments. Subsequently, we evaluate the future change of coastal hazards due to high-swell waves, called Yorimawari waves, caused by strong and stagnant ECs around Japan. The number of ECs passing over the Sea of Japan increased, but the number passing over the Pacific Ocean decreased under future climate. The annual average of the minimum central pressure (MCP) of the EC did not change, but the 10- to 60-year probability value increased for the future. Wave simulations with the d4PDF wind conditions for ECs with an MCP of the 10-year probability value that stagnated for over 24 h around Hokkaido, were conducted. The ensemble average of the maximum significant wave height increased from 0.5 to 1.0 m along the Sea of Japan. The significant wave period increased by over 0.25 s. However, the standard deviation was as large as the wave height of future change. The wave height of high waves depends on the characteristics of the EC.