Preliminary study on impact assessment of climate change on building risks induced by typhoons in Japan

The present paper investigates possible impacts of the climate change on building risks caused by typhoons. The inputs to this investigation are: (1) outcomes from the numerical simulations with a Global Climate Model (GCM) developed under the framework of the KAKUSHIN program, (2) statistics on building damage in the event of Typhoon Songda, and (3) numerical simulation of the wind field induced by the typhoon Songda with the JMA Non- Hydrostatic Model (JMA-NHM). The first input is utilized to develop two sets of probabilistic typhoon models; i.e. corresponding to the current climate and the future climate subject to the climate change, whereas the other inputs are utilized to develop a model for structural performance of buildings. Taking basis in these models, changes of building risks under the climate change are investigated. The result shows that the building risks slightly decrease in most of the regions in Japan, due to the decrease of the frequency of typhoon events, in spite of the increase of the frequency of intensified typhoon events.