2023 Fiscal Year Final Research Report
On formation mechanism of blocking: Excitation from the climatic fields without blocking
Project/Area Number |
18K13617
|
Research Category |
Grant-in-Aid for Early-Career Scientists
|
Allocation Type | Multi-year Fund |
Review Section |
Basic Section 17020:Atmospheric and hydrospheric sciences-related
|
Research Institution | Japan Agency for Marine-Earth Science and Technology |
Principal Investigator |
Yamazaki Akira 国立研究開発法人海洋研究開発機構, 付加価値情報創生部門(アプリケーションラボ), 研究員 (20633887)
|
Project Period (FY) |
2018-04-01 – 2024-03-31
|
Keywords | 大気ブロッキング現象 / 寒気流出 / ストームトラック / 成層圏循環 / 再解析 |
Outline of Final Research Achievements |
In the climatological sense, Interannual variability of atmospheric blocking was investigated. The following three facts could be unvailed. (1) In Northern Hemisphere winter, we found that more (less) frequent blocking is associated with stronger (weaker) southward Northern Hemispheric cold airmass outbreaks and weaker (stronger) storm track activities. (2) Utilizing a global atmospheric data assimilation system, there could be a relationship between reproducibility of a blocking formation and that of a stratospheric circulation in a Southern Hemisphere winter. (3) East Siberian blocking can modulate local structures of the climatological east Asian cold air streams, and then could modulate the barolicnicity and air-sea interaction around Japan, which in turn could contribute to formation of blocking.
|
Free Research Field |
気象学
|
Academic Significance and Societal Importance of the Research Achievements |
ブロッキングの形成メカニズムは昔から注目されるテーマで,いまだに不明な点が多い.そのためか,最近の大気大循環・気候モデルでのブロッキングの予測精度やブロッキングが気候場や極端現象の発生に与える影響の理解も十分でなく,その原因もまだ未解明な点が多い.今回の研究は,こういったブロッキングのメカニズムについて新たな知見を与える.さらに研究課題を通じて,大気大循環・領域モデルやデータ同化システムを使った調査を行ったことで,ブロッキングの気候学的な予測精度の向上のために,モデル・観測・データ同化システムの開発で何を進めるべきかについての方針を与える結果を得た.
|