The modulation of the Quasi-biennial Oscillation associated with climate change(Fostering Joint International Research)

2018 Fiscal Year Final Research Report

• Project/Area Number: 15KK0178
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: KAWATANI Yoshio 国立研究開発法人海洋研究開発機構, 統合的気候変動予測研究分野, 主任研究員 (00392960)
• Research Collaborator: Gray Lesley University of Oxford, Department of Physics, Professor ; Osprey Scott ; Hamilton Kevin ; Anstey James ; Butchart Neal ; Richter Yadga ; Bushell Andrew ; Holt Laura ; Kim Young-Ha
• Project Period (FY): 2016 – 2018
• Keywords: 赤道準２年振動 / 成層圏対流圏結合

Outline of Final Research Achievements

Through Quasi-Biennial Oscillation initiative (QBOi) international project, we investigate the reproductivity of the QBO, QBO modulation associated with climate change and seasonal predictability of the QBO by analyzing multi-model data sets. All models project weaker amplitude of the QBO in the lower stratosphere. On the other hand, QBO periods changes differ significantly among the models. Seasonal predictability of the QBO is relatively well at 20 hPa and during westerly phases but it becomes worse in the lower stratosphere and during easterly phases. We also investigate the roles of the stratosphere in tropospheric climate. Models with well-resolved stratosphere tend to simulate better representation for tropospheric circulations, surface pressure and precipitations.

Free Research Field

中層大気科学

Academic Significance and Societal Importance of the Research Achievements

国際プロジェクトを通して多数の気候モデルデータを解析し、気候変動に伴うQBOの変化について堅固な結果を得られたことは、今後の気候変動予測に有益な知見を与え、気候変動に関する政府間パネル(IPCC)にも貢献する。またQBOの季節予報精度に関する研究は、今後の季節予報スキル向上に役立つ知見を提供し、社会にも還元できる成果である。
成層圏が対流圏の気候に与える影響について詳細に調べた成果は、気候モデルに成層圏を含む必要があることを指摘するものであり、今後の気候モデルコミュニティに有益な知見を与えるものである。