| Project/Area Number |
11219204
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| Research Category |
Grant-in-Aid for Scientific Research on Priority Areas
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| Allocation Type | Single-year Grants |
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| Review Section |
Science and Engineering
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| Research Institution | Kyushu University |
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Principal Investigator |
ITOH Hisanori Kyushu University, Department of Earth and Planetary Sciences, Professor, 大学院・理学研究院, 教授 (80112100)
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| Co-Investigator(Kenkyū-buntansha) |
MIYOSHI Yasunobu Kyushu University, Department of Earth and Planetary Sciences, Associate Professor, 大学院・理学研究院, 助教授 (20243884)
KAWAHIRA Kohji Fukui Prefectural University, Center for Arts and Sciences, Professor, 生物資源学部, 教授 (30025457)
HIROOKA Toshihiko Kyushu University, Department of Earth and Planetary Sciences, Professor, 大学院・理学研究院, 教授 (90253393)
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| Project Period (FY) |
1999 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥40,200,000 (Direct Cost: ¥40,200,000)
Fiscal Year 2002: ¥7,000,000 (Direct Cost: ¥7,000,000)
Fiscal Year 2001: ¥7,000,000 (Direct Cost: ¥7,000,000)
Fiscal Year 2000: ¥10,400,000 (Direct Cost: ¥10,400,000)
Fiscal Year 1999: ¥15,800,000 (Direct Cost: ¥15,800,000)
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| Keywords | Stratospheric ozone / Ozone hole / General circulation / Climate / General circulation model / Arctic oscillation |
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| Research Abstract |
The ozone hole appeared at the end of the 1970s in the Antarctic lower stratosphere and has developed early each austral spring. In addition, large ozone depletion has been observed over the Arctic during early spring in recent years. Hence, we have investigated interannual variations of the general circulation as well as climate and their relationship with polar stratospheric ozone losses by using a general circulation model.
The resultant interannual variability of the general circulation in the stratosphere becomes larger than that in an experiment without polar ozone losses, which is intimately connected with the change of UV heating due to the polar stratospheric ozone change. The spatial pattern of the interannual variation shows a annular seesaw between the Arctic and mid-latitudes in the stratosphere, which furthermore extends down to the troposphere. In the Southern Hemisphere, the interannual change of stronger polar night jets causes a similar variation pattern even in the experiment without polar ozone losses.
The surface portion of the above annular pattern is called to the Arctic Oscillation (AO). We have examined the reality of the AO on the basis of data analyzes over 50 years. Results show that the AO consists of the North Atlantic Oscillation (NAO) and the Pacific/North American (PNA) pattern which are almost independent each other. Therefore, the AO seems to be an apparent pattern. It is also found that the annular pattern observed in the stratosphere is connected only with the NAO near the surface.
To conclude, we have revealed that the large ozone depletion in the stratosphere could induce general circulation changes throughout the stratosphere and troposphere. We must further investigate future evolution of the ozone depletion and its influence on general circulation changes.
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