ESTIMATION OF EXTREME WAVE HEIGHT OF FUTURE CLIMATE BY WRF DYNAMICAL DOWNSCALING SIMULATION OF d4PDF

Abstract

 The intensification of future typhoons and the increase in extreme weather events due to climate change are of concern, making it an urgent task to accurately estimate the extreme wave height for future climates. In this study, we improved the precision and resolution of the wind field using WRF dynamical downscaling simulation with d4PDF meteorological data, and examined a method to efficiently estimate the extreme wave height focusing on specific return periods. To calculate the typhoon central pressure on specific return periods, we performed probability distribution and bias correction of the central pressure based on typhoon track data of actual typhoons and d4PDF. As a bias correction method, we proposed a method of polynomial approximation by double-logarithm transformation of the probability distribution. We suggested estimating the extreme wave height from the mean and standard deviation of the maximum value data set, based on wave calculations for cases with the same typhoon central pressure in the same return period from each climate change scenario. The 50-year extreme wave height under the 2K warmer scenario is estimated to increase approximately 1.05 times compared to the present climate in the central part of Tokyo Bay.