Investigation of the linear relationship between the midlatitude eddy heat flux and fall-to-spring polar ozone buildup

• Project/Area Number: 19K03961
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17020:Atmospheric and hydrospheric sciences-related
• Research Institution: Hokkaido University
• Principal Investigator: Hasebe Fumio 北海道大学, 地球環境科学研究院, 名誉教授 (00261735)
• Co-Investigator(Kenkyū-buntansha): 秋吉 英治 国立研究開発法人国立環境研究所, 地球環境研究センター, シニア研究員 (80211697)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2021: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2020: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 極域オゾン全量 / 渦熱フラックス / 線形性 / オゾン輸送 / オゾン光化学 / アンサンブル実験

Outline of Research at the Start

オゾンホールとして知られる春季極域オゾン破壊は、冬季に発達する極渦内において中低緯度から隔離された成層圏大気中で進行する塩素の活性化を鍵として進行する。極渦の発達と安定性には南北半球間で大きな相違があるため、春季極域オゾン破壊は、しばしば南北別々に議論されるが、Weberらは、中緯度100 hPaにおける冬季の極向き渦熱フラックスと極域オゾン全量の「春/秋」比との間に南北半球を通した極めて良い線形性を見出した。オゾンの春季極大が冬季のオゾン輸送によりもたらされるのは当然としても、極渦内化学過程を無視した議論は成り立たない。本課題は、上述の線形性の根拠を明らかにすることを目指して研究を進める。

Outline of Final Research Achievements

Stratospheric ozone variations simulated by a chemistry-climate model are investigated for the purpose of clarifying the theoretical foundation of the globally-unified linear relationship between the fall-to-spring ozone accumulation in the polar stratosphere and the winter-time eddy heat flux in midlatitudes. Under the recognition that the interannual variations of the poleward ozone transport are controlled by those in the upper stratosphere, the dynamical foundation of the linear relationship is identified by defining a quantity C-EP flux that combines the stratospheric ozone transport with the poleward eddy heat flux. Because of the large inter-hemispheric difference in the chemical ozone depletion, the attempt to express the linear relationship in the globally-unified form should be treated with caution.

Academic Significance and Societal Importance of the Research Achievements

主に熱帯成層圏で生成されるオゾンは、秋から春にかけて成層圏内を極向きに輸送され、高緯度地方に蓄積して春に極大となる。この蓄積量と冬季の中緯度で大気中の波動により極向きに輸送される熱との対応をグラフに表すと、南北半球を区別することなく、一直線上に乗ることが経験的に知られている。この研究では、化学気候モデルによるシミュレーション結果を解析することにより、なぜ、そのような直線関係が成立するのかを明らかにした。得られた結果は、化学的オゾン破壊量の違いが南北半球間で無視できないために、両半球を区別することなく一直線上に乗るという理解には無理のあることを示している。

Research Products

• [Journal Article] Theoretical foundation of the linear relationship between the midlatitude eddy heat flux and fall-to-spring polar ozone buildup (2023)
  • Author(s): Hasebe, F., Kodera, S., Akiyoshi, H.
  • Journal Title: Journal of Atmospheric Sciences Volume: 80 Issue: 3 Pages: 889-908
  • DOI: 10.1175/jas-d-22-0023.1
  • Peer Reviewed / Open Access
• [Journal Article] Dependence of column ozone on future ODSs and GHGs in the variability of 500-ensemble members (2023)
  • Author(s): Akiyoshi Hideharu、Kadowaki Masanao、Yamashita Yousuke、Nagatomo Toshiharu
  • Journal Title: Scientific Reports Volume: 13 Issue: 1
  • DOI: 10.1038/s41598-023-27635-y
  • Peer Reviewed / Open Access
• [Journal Article] Analysis of Arctic spring ozone anomaly in the phases of QBO and 11-year solar cycle for 1979-2017 (2021)
  • Author(s): Yamashita, Y., H. Akiyoshi, and M. Takahashi
  • Journal Title: Atmosphere Volume: 12
  • Peer Reviewed / Open Access
• [Journal Article] Impact of Unmitigated HFC Emissions on Stratospheric Ozone at the End of the 21st Century as Simulated by Chemistry‐Climate Models (2021)
  • Author(s): Dupuy Eric、Akiyoshi Hideharu、Yamashita Yousuke
  • Journal Title: Journal of Geophysical Research: Atmospheres Volume: 126 Issue: 21
  • DOI: 10.1029/2021jd035307
  • Peer Reviewed / Open Access
• [Journal Article] Projecting ozone hole recovery using an ensemble of chemistry-climate models weighted by model performance and independence (2020)
  • Author(s): Amos, M., P. J. Young, J. S. Hosking, J.-F. Lamarque, N. L. Abraham, H. Akiyoshi, A. T. Archibald, S. Bekki, M. Deushi, P. Joeckel, D. Kinnison, O. Kirner, M. Kunze, M. Marchand, D. A. Plummer, D. Saint-Martin, K. Sudo, S. Tilmes, and Y. Yamashita
  • Journal Title: Atmos. Chem. Phys. Volume: 20 Issue: 16 Pages: 9961-9977
  • DOI: 10.5194/acp-20-9961-2020
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] 極域オゾンと中高緯度渦熱フラックスの線形関係に関する考察 (2) (2022)
  • Author(s): 長谷部文雄、小寺沙也加、秋吉英治
  • Organizer: 日本気象学会 2022 年秋季大会
• [Presentation] Impact of unmitigated HFC emissions on stratospheric ozone at the end of the 21st century as simulated by chemistry-climate models (2022)
  • Author(s): Akiyoshi, H., E. Dupuy, Y. Yamashita
  • Organizer: 7th SPARC General Assembly
  • Int'l Joint Research
• [Presentation] CCMI-2022 Ref-D1 stratospheric ozone profiles: trends, natural variability and comparisons to observations and CCMI-1 Ref-C2 (2022)
  • Author(s): Tourpali, K., H. Akiyoshi, F. Dennison, A. Pfeiffer, B. Josse, F. Cheroux, D. Kinnison, P. Colarco, D. Plummer, E. Rozanov, O. Morgenstern, G. Zeng, J. Keeble, I. Petropavlovskikh, S. Godin-Beekmann, N. Azouz, V. Sofieva
  • Organizer: 7th SPARC General Assembly
  • Int'l Joint Research
• [Presentation] Assessment of transport in the latest chemistry climate model initiative (CCMI-2022) simulations (2022)
  • Author(s): Plummer, D., H. Akiyoshi, F. Dennisson, S. Frith, B. Josse, J. Keeble, D. Kinnison, M. Marchand,O. Morgenstern, A. Pfeiffer, E. Rozanov
  • Organizer: 7th SPARC General Assembly
  • Int'l Joint Research
• [Presentation] Analysis of Arctic spring ozone anomaly in the phases of QBO and 11-year solar cycle for 1979-2011 (2021)
  • Author(s): Yamashita, Y., H. Akiyoshi, M. Takahashi
  • Organizer: JpGU Meeting 2021 (日本地球惑星科学連合2021年大会)
  • Int'l Joint Research
• [Presentation] A CCM forecast experiments of the ozone reduction event over the southern tip of south America in November 2009 using ozone assimilated initial data (2021)
  • Author(s): Nakamura, H., T. Hirooka, H. Akiyoshi, T. Sugita, A. Mizuno
  • Organizer: Quadrennial Ozone Symposium 2021
  • Int'l Joint Research
• [Presentation] Insights into the linear relationship between extratropical eddy heat flux and polar ozone build-up (2021)
  • Author(s): Hasebe, F., S. Kodera, and H. Akiyoshi
  • Organizer: Quadrennial Ozone Symposium 2021
  • Int'l Joint Research
• [Presentation] Analysis of Arctic spring ozone anomaly in the phases of QBO and 11-Year solar cycle for 1979-2017 (2021)
  • Author(s): Yamahsita, Y., H. Akiyoshi, M. Takahashi
  • Organizer: Quadrennial Ozone Symposium 2021
  • Int'l Joint Research
• [Presentation] Impact of unmitigated HFC emissions on stratospheric ozone at the end of the 21st century as simulated by chemistry-climate models (2021)
  • Author(s): Dupuy, E., H. Akiyoshi, Y. Yamashita
  • Organizer: Quadrennial Ozone Symposium 2021
  • Int'l Joint Research
• [Presentation] ODS and GHG dependence of total ozone at mid- and high latitudes indicated by multi-ensemble simulations using MIROC3.2 and MIROC5 chemistry-climate models (2020)
  • Author(s): Akiyoshi, H., M. Kadowaki, Y. Yamashita, E. Dupuy, T. Nagatomo
  • Organizer: JpGU-AGU Joint Meeting 2020、Virtual meeting（オンライン開催）
  • Int'l Joint Research
• [Presentation] 500アンサンブル実験による低中高緯度オゾン全量のODS・GHG濃度依存性 (2019)
  • Author(s): 秋吉英治, 門脇正尚, 山下陽介, 長友正晴
  • Organizer: 日本気象学会 2019年度秋季大会