[A-OS07] 季節内から十年規模の気候変動と予測可能性

[AOS07-01] Seasonal Predictions of Tropical Cyclones in 2018 using GFDL and NICAM High-Resolution Global Models

★Invited Papers

*村上 裕之^1,2、中野 満寿男³、V Ramaswamy¹、Thomas Delworth¹、Sarah Kapnick¹、Rich Gudgel¹、望月 崇³、土井 威志³、森岡 優志³ (1.地球流体学研究所、2.大気研究大学連盟、3.海洋研究開発機構)

キーワード：熱帯低気圧、季節予測、Pacific Meridional Mode、人為起源強制力、台風、地球温暖化

We conduct real-time seasonal forecast using high-resolution global models (GFDL-FLOR, GFDL-HiFLOR, and NICAM) that have skill in predicting tropical cyclone statistics over the global ocean basins. The seasonal predictions starting from 2018 July initial conditions show above normal frequency of tropical cyclones in the Western North Pacific and Central Pacific Oceans as observed. To understand physical mechanisms behind the active storm season in the Pacific, we conducted idealized seasonal forecasts by changing sea surface temperature spatial patterns, which is so called "real-time attribution" simulations. We find out that warmer subtropical Pacific associated with positive Pacific Meridional Mode (PMM), rather than central Pacific El Nino, was responsible for the active storm season. In the presentation, we will also show preliminary results for impact of anthropogenic forcing on the 2018 active storm season.