[A-AS02] Extreme Events: Observations and Modeling

[AAS02-02] Assessing the Impacts of Extreme Weather on Local-Scale Hazards under Climate Change

★Invited Papers

*Tetsuya Takemi¹ (1.Disaster Prevention Research Institute, Kyoto University)

Keywords:extreme weather, dynamical downscaling, climate change impact, urban disaster risk, global warming

Understanding hazards and risks due to extreme weather phenomena is critically important in order to consider disaster risk reduction under climate change. Quantitative representations of meteorological hazards are critically important in order to assess the impacts of such hazards not only for past disastrous events but also as for anticipated extreme events under future global warming. Furthermore, hazard information at local-scales is required because the resulting phenomena occur depending on their local geographic features. Since the Innovative Program of Climate Change Projection for the 21st Century (KAKUSHIN Program, FY2007-2012) funded by the Japanese Government, we have been studying the impacts of extreme weather under future global warming under the subsequent Program for Risk Information on Climate Change (SOUSEI Program, FY2012-2017) and the latest Integrated Research Program for Advancing Climate Models (TOUGOU Program FY2017-). Meteorological hazards such as heavy rainfalls, strong winds, and tropical cyclones were quantitatively examined as case studies. In this presentation, we will talk about how the quantitative representation of meteorological hazards helps to assess the impacts of the hazards for climate change adaptation and disaster risk reduction. We will focus on tropical cyclones and heavy rainfalls as extreme weather and use a dynamical downscaling technique with the Weather Research and Forecasting (WRF) model for the impact assessment studies. Past extreme weather that caused severe disaster can be regarded as a baseline to consider local-scale hazards. The impacts of climate change are investigated with the use of pseudo-global warming technique in which warming increments are added to past meteorological fields. The results from case studies on tropical cyclones and heavy rainfalls are demonstrated in this presentation. Furthermore, the analysis of airflows downscaling to urban districts with the use of a building-resolving large-eddy simulation model is demonstrated. Strong wind hazards are quantitatively assessed by the building-resolving modelling technique.