Characteristics and formation mechanisms of the subtropical convergence zones in the global atmosphere

2011 Fiscal Year Final Research Report

• Project/Area Number: 21540449
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Hirosaki University
• Principal Investigator: KODAMA Yasumasa 弘前大学, 大学院・理工学研究科, 准教授 (30205421)
• Co-Investigator(Kenkyū-buntansha): SATO Naoki 東京学芸大学, 自然科学系, 講師 (90392935)
• Co-Investigator(Renkei-kenkyūsha): NINOMIYA Kozo 独立行政法人海洋研究開発機構, 地球環境変動領域, 特任上席研究員 (60292950) ; KAWAMURA Ryuichi 富山大学, 大学院・理工学研究科, 教授 (30303209) ; YOSHIKANE Takao 独立行政法人海洋研究開発機構, 地球環境変動領域, 主任研究員 (40392964)
• Project Period (FY): 2009 – 2011
• Keywords: 亜熱帯収束帯 / SACZ / SPCZ / 梅雨前線帯 / 亜熱帯ジェット気流 / 大気海洋相互作用

Research Abstract

There are three subtropical convergence zones (STCZ) in the global atmosphere. The Baiu frontal zone is one of them. We studied mechanisms how each STCZ is maintained. We examined the roles of the Brazilian Plateau in maintaining the SACZ (South Atlantic convergence zone) by data analysis of long-term observation and numerical experiments. On the roles of subtropical jets, we found that the hypotheses proposed by Sampe and Xie (2010), in which warm advection by jet in the middle troposphere may intensify the rainfall along the Baiu frontal zone, can be applied for the SACZ and the SPCZ (South Pacific convergence zone). The Baiu frontal zone has direction and latitudes differ from those of the other STCZs in the Southern Hemisphere. Dynamic influence of Kuroshio current on these unique features of the Baiu frontal zone was discussed using observational data of the ocean.

Research Products

• [Journal Article] The Madden-Julian Oscillation and extratropical teleconnection over East Asia during the Northern winter in IPCC AR4 climate models (2012)
  • Author(s): Takahashi, C., K. Yoneyama, N. Sato, A. Seiki, R. Shirooka, and Y. N. Takayabu
  • Journal Title: J. Meteor. Soc. Japan Volume: (in press)
• [Journal Article] Relationship of the reproducibility of multiple variables among global climate models (2012)
  • Author(s): Nishii, K., T. Miyakawa, H. Nakamura, Y. Kosaka, S. Yokoi, Y. N. Takayabu, H. Endo, H. Ichikawa, T. Inoue, K. Oshima, N. Sato, and Y. Tsushima
  • Journal Title: J. Meteor. Soc. Japan Volume: (in press)
• [Journal Article] Impact of Arctic sea-ice retreat on the recent change in cloud-base height during autumn (2012)
  • Author(s): Sato, K., J. Inoue, Y.-M. Kodama, and J. E. Overland
  • Journal Title: Geophysical Research Letters Volume: 39 Pages: L10503, 6
  • DOI: doi:10.1029/2012GL051850
• [Journal Article] Roles of the Brazilian Plateau in the formation of the SACZ (2012)
  • Author(s): Y.-M. Kodama, T. Sagawa, S. Ishida, and T. Yoshikane
  • Journal Title: J. Climate Volume: 25 Pages: 1745-1758
• [Journal Article] Projected future change of MJO and its extratropical teleconnection in East Asia during the northern winter simulated in IPCC AR4 Models (2012)
  • Author(s): Takahashi, C., N. Sato, A. Seiki, K. Yoneyama, and R. Shirooka
  • Journal Title: SOLA Volume: 7 Pages: 201-204
• [Journal Article] Application of cluster analysis to climate model performance metrics (2011)
  • Author(s): Yokoi, S., Y. N. Takayabu, K. Nishii, H. Nakamura, H. Endo, H. Ichikawa, T. Inoue, M. Kimoto, Y. Kosaka, T. Miyasaka, K. Oshima, N. Sato, Y. Tsushima, and M. Watanabe
  • Journal Title: J. Appl. Meteor. Clim Volume: 50 Pages: 1666-1675
• [Journal Article] The influence of observations propagated by convectively coupled equatorial waves Quart (2011)
  • Author(s): Moteki, Q., K. Yoneyama, R. Shirooka, H. Kubota, K. Yasunaga, J. Suzuki, A. Seiki, N. Sato, T. Enomoto, T. Miyoshi, and S. Yamane
  • Journal Title: J. Roy. Meteor. Soc Volume: 137
  • DOI: doi:10.1002/qj.779
• [Journal Article] Charcteristics of atmospheric waves in the upper troposphere observe dwith the Gadanki MST Radar-RASS (2011)
  • Author(s): T.V. C. Sarma, Y.-M. Kodama, and T. Tsuda
  • Journal Title: J. Atmospheric and Solar-Terrestrial Physics Volume: 73 Pages: 1020-1030
• [Journal Article] Climatology of warm rain and associated latent heating derived from TRMM-PR observations (2009)
  • Author(s): Y.-M. Kodama, M. Katsumata, S. Mori, S. Satoh, Y. Hirose, and H. Ueda
  • Journal Title: J. Climate Volume: 22 Pages: 4908-4929
• [Journal Article] Air mass transformation along trajectories of airflow and its relation to the vertical structures of the maritime atmopshoere and clouds in Yamase events (2009)
  • Author(s): Y.-M. Kodama, Y. Tomiya and S. Asano
  • Journal Title: Journal of the Meteorological Society of Japan Volume: 87 Pages: 665-685
• [Journal Article] Diurnal and intraseasonal variation of UTLS vertical wind disturbance in the equatorial region and its relation to tropospheric convective activities (2009)
  • Author(s): Kozu, T., Y.-M. Kodama, Y. Shibagaki, T. Shimomai, M. Kawashima, and S. P. Alexander
  • Journal Title: Earth, Planets and Space Volume: 61(4) Pages: 535-544
• [Presentation] Roles of the Brazilian Plateau in the formation of the SACZ (2011)
  • Author(s): Y.-M. Kodama
  • Organizer: IUGG2011
  • Place of Presentation: メルボルン、オーストラリア
  • Year and Date: 20110602-0713
• [Remarks]
  • URL: http://www.st.hirosaki-u.ac.jp/~kodama/#senmon