Elucidation of global carbon cycle and its climate response

• Project/Area Number: 18H01275
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 17020:Atmospheric and hydrospheric sciences-related
• Research Institution: Tohoku University
• Principal Investigator: AOKI Shuji 東北大学, 理学研究科, 学術研究員 (00183129)
• Co-Investigator(Kenkyū-buntansha): 森本 真司 東北大学, 理学研究科, 教授 (30270424)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥16,120,000 (Direct Cost: ¥12,400,000、Indirect Cost: ¥3,720,000); Fiscal Year 2021: ¥3,250,000 (Direct Cost: ¥2,500,000、Indirect Cost: ¥750,000); Fiscal Year 2020: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2019: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2018: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
• Keywords: 二酸化炭素 / 酸素 / 炭素同位体 / 陸上生物圏 / 海洋 / 二酸化炭素濃度 / 同位体比 / 酸素濃度 / モデル / 炭素同位体比 / 全球大気化学輸送モデル / 陸域生態系モデル / 全球3次元大気化学輸送モデル

Outline of Final Research Achievements

Global scale observations of CO2 concentration, the carbon isotopic ratio (delta13C) of CO2, and oxygen concentration (delta(O2/N2)) in the atmosphere have been made since 2001. Based on the observed secular trends of CO2 concentration and delta(O2/N2) as well as anthropogenic CO2 emission data, the average uptake rates of the anthropogenic CO2 during 2001-2020 among the atmosphere, the terrestrial biosphere and the ocean were estimated to be 44±0.3％, 33±6％ and 23±6％, respectively. By using the observed CO2 and delta13C, the corresponding CO2 uptakes were in good agreement with the former method within the estimated error ranges. The terrestrial biospheric CO2 uptake showed large interannual variability in association with El Nino events.

Academic Significance and Societal Importance of the Research Achievements

化石燃料消費によって大気に大量に放出された二酸化炭素が海洋と陸上植物によってどのくらい吸収され、大気にどのくらい在留するかを正確に求めることは、今後の地球温暖化予測にとって重要な課題である。本研究ではそれらをCO2濃度とO2濃度観測から求める方法と、CO2濃度とその炭素同位体から求める方法を用いて解析したが、２つの独立した手法から得られた結果が誤差の範囲で一致したことから、信頼性が高い結果が得られたと結論づけられる。

Research Products

• [Journal Article] Shipboard observations of atmospheric oxygen in the Southern Ocean during the 2017-2018 austral summer (2021)
  • Author(s): Morimoto, S., S. Takebayashi, D. Goto, G.Hashida, and S. Aoki
  • Journal Title: Polar Science, Volume: 29 Pages: 1-9
  • DOI: 10.1016/j.polar.2021.100691
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Antarctic surface temperature and elevation during the Last Glacial Maximum (2021)
  • Author(s): Christo Buizert, T. J. Fudge, William H. G. Roberts, Eric J. Steig, Sam Sherriff-Tadano, Catherine Ritz, Eric Lefebvre, Jon Edwards, Kenji Kawamura, Ikumi Oyabu, Hideaki Motoyama, 他（全42名）
  • Journal Title: Science Volume: 372 (6546) Issue: 6546 Pages: 1097-1101
  • DOI: 10.1126/science.abd2897
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Composition of firn air at the North Greenland Ice Core Project (NGRIP) site (2021)
  • Author(s): Kawamura, K., T. Umezawa, S. Sugawara, S. Ishidoya, K. Ishijima, T. Saito, I Oyabu, S. Murayama, S. Morimoto, S. Aoki, and T. Nakazawa
  • Journal Title: Polar Data Journal Volume: 5 Pages: 89-98
  • DOI: 10.20575/00000030
  • NAID: 120007143946
  • ISSN: 2432-6771
  • URL: http://id.nii.ac.jp/1434/00000030/
  • Peer Reviewed / Open Access
• [Journal Article] Fractionation of O2/N2 and Ar/N2 in the Antarctic ice sheet during bubble formation and bubble-clathrate hydrate transition from precise gas measurements of the Dome Fuji ice core (2021)
  • Author(s): Oyabu, I., Kawamura, K., Uchida, T., Fujita, S., Kitamura, K., Hirabayashi, M., Aoki, S., Morimoto, S., Nakazawa, T., Severinghaus, J. P., and Morgan, J. D.
  • Journal Title: The Cryosphere Volume: 15 Issue: 12 Pages: 5529-5555
  • DOI: 10.5194/tc-15-5529-2021
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Global and regional CH4 emissions for 1995-2013 derived from atmospheric CH4, d13C-CH4 and dD-CH4 observations and a chemical transport model (2020)
  • Author(s): Fujita, R., S. Morimoto, S. Maksyutov, H.-S. Kim, M. Arshinov, S. Aoki, and T. Nakazawa
  • Journal Title: J. Geophys. Res., Atmospheres Volume: - Issue: 14 Pages: 1-23
  • DOI: 10.1029/2020jd032903
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Spatio-temporal variations of the atmospheric greenhouse gases and their sources and sinks in the Arctic region (2020)
  • Author(s): Morimoto, S., D. Goto, S. Murayama, R. Fujita, Y. Tohjima, S. Ishidoya, T. Machida, Y. Inai, P. K. Patra, S. Maksyutov, A. Ito, and S. Aoki
  • Journal Title: Polar Science Volume: -
• [Journal Article] New technique for high-precision, simultaneous measurements of CH<sub>4</sub>, N<sub>2</sub>O and CO<sub>2</sub> concentrations; isotopic and elemental ratios of N<sub>2</sub>, O<sub>2</sub> and Ar; and total air content in ice cores by wet extraction (2020)
  • Author(s): Oyabu Ikumi、Kawamura Kenji、Kitamura Kyotaro、Dallmayr Remi、Kitamura Akihiro、Sawada Chikako、Severinghaus Jeffrey P.、Beaudette Ross、Orsi Ana?s、Sugawara Satoshi、Ishidoya Shigeyuki、Dahl-Jensen Dorthe、Goto-Azuma Kumiko、Aoki Shuji、Nakazawa Takakiyo
  • Journal Title: Atmospheric Measurement Techniques Volume: 13 Issue: 12 Pages: 6703-6731
  • DOI: 10.5194/amt-13-6703-2020
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Implication of tropical lower stratospheric cooling in recent trends in tropical circulation and deep convective activity (2019)
  • Author(s): Kodera, K., N. Eguchi, R. Ueyama, Y. Kukoda, C. Kobayashi, Beatriz M. Funatsu, and Chantal Claud
  • Journal Title: Atmospheric Chemistry and Physics Volume: 19 Issue: 1 Pages: 2655-2669
  • DOI: 10.5194/acp-19-1-2019
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Seasonal characteristics of trace gas transport into the extratropical upper troposphere and lower stratosphere (2019)
  • Author(s): Inai, Y., T. Machida, H. Matsueda, Y. Sawa, K. Tsuboi, K. Katsumata, S. Morimoto, S. Aoki, and T.,Nakazawa
  • Journal Title: Atmos. Chem. Phys. Volume: 19 Issue: 10 Pages: 7073-7103
  • DOI: 10.5194/acp-19-7073-2019
  • Peer Reviewed / Open Access
• [Journal Article] Temporal variations of the mole fraction, carbon and hydrogen isotope ratios of atmospheric methane in the Hudson Bay Lowlands, Canada. (2018)
  • Author(s): Fujita, R., S. Morimoto, T. Umezawa, K. Ishijima, P. K. Patra, D. E. J. Worthy, D. Goto, S. Aoki and T. Nakazawa
  • Journal Title: J. Geophys. Res. Volume: 123 Issue: 9 Pages: 4695-4711
  • DOI: 10.1002/2017jd027972
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Balloon-borne tropospheric CO 2 observations over the equatorial eastern and western Pacific (2018)
  • Author(s): Inai Yoichi、Aoki Shuji、Honda Hideyuki、Furutani Hiroshi、Matsumi Yutaka、Ouchi Mai、Sugawara Satoshi、Hasebe Fumio、Uematsu Mitsuo、Fujiwara Masatomo
  • Journal Title: Atmospheric Environment Volume: 184 Pages: 24-36
  • DOI: 10.1016/j.atmosenv.2018.04.016
  • Peer Reviewed / Open Access
• [Journal Article] Coordinated Upper-troposphere-to-stratosphere Balloon Experiment in Biak (CUBE/Biak) (2018)
  • Author(s): Hasebe, F., S. Aoki, S. Morimoto, Y. Inai, T. Nakazawa, S. Sugawara, C. Ikeda, H. Honda, H. Yamazaki, Halimurrahman, N. Komala, F. Putri, A. Budiyono, M. Soedjarwo, S. Ishidoya, S. Toyoda, T. Shibata, M. Hayashi, N. Eguchi, N. Nishi, M. Fujiwara, S. Ogino, M. Shiotani, and T. Sugidachi
  • Journal Title: Bulletin of the American Meteorological Society Volume: 99 Issue: 6 Pages: 1213-1230
  • DOI: 10.1175/bams-d-16-0289.1
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Gravitational separation of the stratospheric air over Syowa, Antarctica and its connection with meteorological fields (2018)
  • Author(s): Ishidoya, S., S. Sugawara, Y. Inai, S. Morimoto, H. Honda, C. Ikeda, Y. Tomikawa, S. Toyoda, D. Goto, S. Aoki, and T. Nakazawa
  • Journal Title: Atmos Sci Lett. Volume: e857 Issue: 11 Pages: 1-7
  • DOI: 10.1002/asl.857
  • Peer Reviewed
• [Presentation] Vertical profiles of halocarbons in the stratosphere over Japan in 2020 and implications for the “mean age” of stratospheric air (2022)
  • Author(s): Shoko Hikichi, Shinji Morimoto, Taku Umezawa, Takuya Saito, Sakae Toyoda, Satoshi Sugawara, Shigeyuki Ishidoya, Hideyuki Honda and Shuji Aoki
  • Organizer: JpGU 2022
• [Presentation] 大気ポテンシャル酸素の季節変動に対する 南北半球間大気輸送の影響 (2021)
  • Author(s): 石戸谷重之, 丹羽洋介, 坪井一寛, 森本真司, 遠嶋康徳, 後藤大輔, 青木周司, 村山昌平, 青木伸行, 石島健太郎, 亀崎和輝, 松枝秀和
  • Organizer: 大気化学討論会
• [Presentation] ractionation of O2/N2 and Ar/N2 in the Antarctic ice sheet from precise gas measurements of the Dome Fuji ice core -Constraining permeabilities of O2, N2 and Ar in the ice sheet with a simple diffusion model- (2021)
  • Author(s): Ikumi Oyabu, Kenji Kawamura, Tsutomu Uchida, Shuji Fujita, Kyotaro Kitamura, Motohiro Hirabayashi, Shuji Aoki, Shinji Morimoto, Takakiyo Nakazawa, Jeffrey P. Severinghaus, Jacob D. Morgan
  • Organizer: The 12th symposium on Polar Science
  • Int'l Joint Research
• [Presentation] Variations of partial pressure of CO2 in the surface seawater (2021)
  • Author(s): Takayuki Matsuura, Shinji Morimoto, Gen Hashida, Tomomi Takamura, Shin-ichiro Nakaoka and Shuji Aoki
  • Organizer: The 12th symposium on Polar Science
  • Int'l Joint Research
• [Presentation] ドームふじ氷床コアにおけるO2/N2とAr/N2の分別 (2021)
  • Author(s): 大藪幾美，川村賢二，内田努，藤田秀二，北村享太郎，平林幹啓，青木周司，森本真司，中澤高清
  • Organizer: JSSI & JSSE Joint Conference, 2021
• [Presentation] 成層圏大気重力分離と空気年齢の新たな応用;海洋貯熱量変動評価における重要性 (2021)
  • Author(s): 石戸谷重之，菅原敏，青木周司，森本真司，本田秀之，豊田栄， 遠嶋康徳，後藤大輔，石島健太郎，長谷部文雄，丹羽洋介，青木伸行， 村山昌平，飯島一征，吉田哲也
  • Organizer: 大気球シンポジウム
• [Presentation] Temporal and spatial variations of the mole fraction, carbon and hydrogen isotope ratios of atmospheric methane in the western Pacific region (2021)
  • Author(s): Mahito Yasuda, Shinji Morimoto, Shuji Aoki, Ryo Fujita, and Taku Umezawa
  • Organizer: JpGU 2021
• [Presentation] In-situ and continuous observation of atmospheric N2O and CO concentrations at Syowa Station, Antarctica (2020)
  • Author(s): 赤井 章吾、森本 真司、李 偉、後藤 大輔、青木 周司
  • Organizer: JpGU-AGU Joint Mee ting 2020
• [Presentation] Studies on variations of atmospheric greenhouse gases in the ArCS project 2015-2019 (2020)
  • Author(s): Shinji Morimoto, Daisuke Goto, Shohei Murayama, Ryo Fujita, Yasunori Tohjim, Shigeyuki Ishidoya, Toshinobu Machida, Kazuhiro Tsuboi, Yoichi Inai, Prabir K. Patra, Shamil Maksyutov, Akihiko Ito and Shuji Aoki
  • Organizer: 極域科学シンポジウム2020
• [Presentation] マルチクロックトレーサーによる大気年代推定（B20-04 結果速報） (2020)
  • Author(s): 菅原敏, 青木周司, 森本真司, 本田秀之, 豊田栄, 石戸谷重之, 後藤大輔, 梅澤拓，長谷部文雄、石島健太郎、飯嶋一征, 吉田哲也
  • Organizer: 大気球シンポジウム2020
• [Presentation] In-situ observation of atmospheric N2O and CO concentrations st Syowa Station, Antarctica (2020)
  • Author(s): Shogo Akai, Shinji Morimoto, Li Wei, Daisuke Goto, Shuji Aoki
  • Organizer: JpGU-AGU Joint Mee ting 2020
• [Presentation] Atmospheric Gases and Isotopes as Passive Tracers of Climatic Processes (2020)
  • Author(s): Shigeyuki Ishidoya, Satoshi Sugawara, Shinji Morimoto, Daisuke Goto, Yasunori Tohjima, Kentaro Ishijima, Dmitry Belikov, Fumio Hasebe, Kazuhiro Tsuboi, Shohei Murayama, Nobuyuki Aoki, Shuji Aoki, Takakiyo Nakazawa
  • Organizer: AGU fall meeting 2020
• [Presentation] Selection bias of quasi-fixed-point observations in the ExUTLS and its impact on the seasonal record (2019)
  • Author(s): Yoichi Inai, Toshinobu Machida, Hidekazu Matsueda, Yousuke Sawa, Kazuhiro Tsuboi, Keiichi Katsumata, Shinji Morimoto, Shuji Aoki, Takakiyo Nakazawa, Ryo Fujita
  • Organizer: 日本地球惑星科学連合2019年大会
• [Presentation] Accurate chronology and climatic reconstruction around MIS 11 (interglacial period ~400,000 years ago) from Dome Fuji ice core, Antarctica (2019)
  • Author(s): Kenji Kawamura, Ikumi Oyabu, Shuji Aoki, Takakiyo Nakazawa, Ayako Abe-Ouchi, Fuyuki SAITO
  • Organizer: 日本地球惑星科学連合2019年大会
• [Presentation] Global inverse analysis of CH4 fluxes using NICAM-TM 4D-Var (2019)
  • Author(s): Yosuke Niwa, Akihiko Ito, Toshinobu Machida, Motoki Sasakawa, Yasunori Tohjima, Yukio Terao, Taku Umezawa, Shinji Morimoto, Shuji Aoki, 他
  • Organizer: 日本地球惑星科学連合2019年大会
• [Presentation] レーザー分光法による大気中N2OおよびCO濃度連続観測システムの開発と南極・昭和基地における大気観測への応用 (2019)
  • Author(s): 赤井章吾、森本真司、李偉、後藤大輔、青木周司
  • Organizer: 日本気象学会
• [Presentation] マルチクロックトレーサーによる大気年代の推定 (2019)
  • Author(s): 菅原敏, 青木周司, 森本真司, 稲飯洋一, 本田秀之, 豊田栄, 石戸谷重之, 後藤大輔, 梅澤拓, 長谷部文雄, 石島健太郎
  • Organizer: 大気球シンポジウム
• [Presentation] Development of a continuous measurement system for atmospheric N2O and CO concentrations and its application to in-situ observation at Syowa Station, Antarctica (2019)
  • Author(s): Shogo Akai, Shinji Morimoto, Li Wei, Daisuke Goto, Shuji Aok
  • Organizer: 極域科学シンポジウム
• [Presentation] 熱帯成層圏大気の重力分離とその数値シミュレーション (2018)
  • Author(s): 菅原敏, 石戸谷重之, 青木周司，森本真司，中澤高清， 稲飯洋一，本田秀之，豊田栄， 長谷部文雄，池田忠作，後藤大輔
  • Organizer: 日本気象学会
• [Presentation] Measurements of δ13C and δD of atmospheric CH4 in the northern North Pacific and the Arctic Ocean and interpretation of Arctic CH4 sources (2018)
  • Author(s): R. Fujita S. Morimoto1, S. Ishidoya2, Y. Tohjima3, K. Ishijima4, S. Aoki1 and T. Nakazawa
  • Organizer: IGAC
• [Presentation] Past variations of atmospheric methane and its isotope ratios reconstructed from firn air and ice core measurements (2018)
  • Author(s): Taku Umezawa, Satoshi Sugawara, Kenji Kawamura, Takanori Sugiyama, Prabir K. Patra, Kentaro Ishijima, Takuya Saito, Shinji Morimoto, Shuji Aoki and Takakiyo Nakazawa
  • Organizer: IGAC
• [Presentation] Temporal variations of the mole fraction and carbon isotope ratio of atmospheric methane observed at Ny-Alesund, Svalbard and Syowa Station, Antarctica (2018)
  • Author(s): Shinji Morimoto, Ryo Fujita, Shuji Aoki, Daisuke Goto and Takakiyo Nakazawa
  • Organizer: IGAC
• [Presentation] In-situ continuous observations of atmospheric O2/N2 ratio and CO2 concentration on-board “SHIRASE” in the Southern Ocean (2018)
  • Author(s): S. Takebayashi, S. Morimot1, D. Goto, G. Hashida, Y. Inai and S. Aoki
  • Organizer: 極域科学シンポジウム
• [Book] 南極読本 (2019)
  • Author(s): 阿保敏広、青木周司、ほか28名
  • Total Pages: 270
  • Publisher: 成山堂書店
  • ISBN: 9784425948123