2018 Fiscal Year Final Research Report
Clarification of cessation mechanisms of tropical cyclone intensification for developing tropical cyclone intensity forecasts
| Project/Area Number |
15K05292
|
|---|
| 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 | Japan, Meteorological Research Institute |
|---|
Principal Investigator |
WADA Akiyoshi 気象庁気象研究所, 台風研究部, 主任研究官 (20354475)
|
|---|
| Research Collaborator |
USUI Norihisa
Chakraborty Pinaki
KANADA Sachie
KUNII Masaru
SAWADA Masahiro
TAKAMURA Nao
|
|---|
| Project Period (FY) |
2015-04-01 – 2019-03-31
|
| Keywords | 大気海洋相互作用 / 台風 / 数値モデル / 数値予測 |
|---|
| Outline of Final Research Achievements |
By comparing the simulation results of tropical cyclones (TCs) Haiyan (2013) and Mike (1990) performed by the regional atmosphere-wave-ocean coupled model, we propose the following processes associated with the intensification and subsequent termination: (1) the moving speed ofTC are largely influenced by atmospheric environments. The faster the moving speed, the smaller the TC-induced sea surface cooling (SSC). (2) Warm and moisten air was supplied toward the TC center by surface frictiononal flow convergence in the atmospheric boundary layer. (3) The faster moving speed, the stronger a convergence area is formed ahead of the TC, causing strong convection. (4) When the convection burst is suppressed due to warming and stabilization of the atmosphere, intensification is less likely to occur. From the simulation results of Lionrock (2016) by global atmosphere-ocean coupled model, the TC track and intensity and TC-induced SSC was greatly affected by cumulus convection scheme.
|
| Free Research Field |
数物系科学
|
| Academic Significance and Societal Importance of the Research Achievements |
台風強度予測は進路予測と比べて目立った発展が見られなかった原因の１つとして、台風発達メカニズムを支配する大気力学及び海洋の効果を台風予測技術に十分反映させてこなかったことが挙げられる。本研究では非静力学大気波浪海洋結合モデル等を用いて、台風に関する様々な数値実験や数値シミュレーションを実施した。本研究にて発達期後の台風強化停止過程及び台風の衰退期における強度維持過程のメカニズムを解明したことは、台風強度変化メカニズムに新たな知見を与えた。また大気海洋相互作用と積雲・雲過程が数値モデルにより異なることによる台風強化停止過程の違いは今後の台風予測システムを発展する上で重要な知見となった。
|
