Rapid Deepening Mechanism of an Extremely Intense Tropical Cyclone

2016 Fiscal Year Final Research Report

• Project/Area Number: 26400466
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Nagoya University
• Principal Investigator: KANADA Sachie 名古屋大学, 宇宙地球環境研究所, 特任助教 (80727628)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 熱帯低気圧 / 雲解像モデル / 急発達

Outline of Final Research Achievements

Rapid deepening mechanism of an extremely intense tropical cyclone was studied by using a high-resolution cloud resolving model with a horizontal resolution of a few kilometers that can represent the inner-core structures and processes of the tropical cyclone.
First, we conducted numerical simulations of Typhoon Ida (1958), an extremely intense typhoon with a minimum central pressure of 877 hPa. Extremely rapid deepening of the maximum central pressure drop exceeding 90 hPa/24h was successfully simulated. The model-resolution sensitivity experiments revealed that only the cloud-resolving 2km model could reproduce the maximum intensity and intensification rate of Typhoon Ida since the model could produce the convective activity around the storm core region.
We further investigated future changes of an extremely intense tropical cyclone. The results suggest that the maximum intensity and intensification rate of an extremely intense typhoon will increase in the future warmer climate.

Free Research Field

気象学