講演情報
[ACG45-P10]Large ensemble high-resolution climate simulations – Application to Event Attribution study
*今田 由紀子1、前田 修平1、渡部 雅浩2、塩竈 秀夫3、水田 亮1、石井 正好1、木本 昌秀2 (1.気象庁気象研究所、2.大気海洋研究所、3.国立環境研究所)
キーワード：
Large ensemble climate simulation、AGCM、Extreme event、Heatwaves、Pacific decadal variability、Global warming
Recently, an unprecedentedly large ensemble of climate simulations with a 60 km atmospheric general circulation model and dynamical downscaling with a 20 km regional climate model have been released in Japan (the “Database for Policy Decision making for Future climate change [d4PDF]”) to assess probabilistic change in localized severe events that have large uncertainty from internal variability. Internal variability includes decadal variations in the ocean, inter-annual variability in the extratropical atmosphere, intra-seasonal variation in the tropics, and so on. Two sets of ensemble for past climate with and without historical trends associated with the anthropogenic effect, respectively, and an ensemble for 4 K warmer future climate are simulated more than 5000 years in d4PDF. Here, we will introduce our recent works using large ensemble simulations focusing on how much the inter-annual and decadal variability in the Pacific Ocean contributed to increased occurrence of heatwaves around the globe when compared to anthropogenic global warming.