Future projection of tropical cyclone precipitation over Japan with a high-resolution regional climate model

Abstract

This study evaluates possible changes in tropical cyclone (C) precipitation over Japan under a future warmer climate using an ensemble projection generated by a non-hydrostatic regional climate model with a resolution of 5 km (HRCM05) under the RCP8.5 scenario. HRCM05 reproduces C precipitation and C intensity more accurately than does a general circulation model with a resolution of 20 km. he number of Cs approaching Japan is projected to decrease under the future climate, while the C precipitation rate increases. s these two effects cancel each other out, total C precipitation, and the frequency of the moderate C precipitation that is usual under the present climate, shows no significant change. On the other hand, the frequency of extreme C precipitation increases significantly because the intensification of the C precipitation rate outweighs the reduction in C frequency. he increase in the C precipitation rate is caused primarily by the increase in water vapor around the Cs, which in turn results from the increase in environmental water vapor. he intensification and structural changes to Cs also contribute to the enhanced C precipitation.