ESTIMATION OF SURFACE AIR TEMPERATURE CHANGE USING AN ATMOSPHERIC GENERAL CIRCULATION MODEL
Project/Area Number |
14048208
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Research Category |
Grant-in-Aid for Scientific Research on Priority Areas
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Allocation Type | Single-year Grants |
Review Section |
Science and Engineering
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Research Institution | The University of Tokyo |
Principal Investigator |
IMASU Ryoichi University of Tokyo, Center for Climate System Research, Associate Professor, 気候システム研究センター, 助教授 (40334255)
|
Co-Investigator(Kenkyū-buntansha) |
MAEDA Takahisa National Institute of Advanced Industrial Science and Technology, Research Institute for Environmental Management Technology, Researcher, 環境管理研究部門, 研究員 (10357981)
|
Project Period (FY) |
2002 – 2005
|
Project Status |
Completed (Fiscal Year 2005)
|
Budget Amount *help |
¥19,000,000 (Direct Cost: ¥19,000,000)
Fiscal Year 2005: ¥5,000,000 (Direct Cost: ¥5,000,000)
Fiscal Year 2004: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 2003: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2002: ¥11,000,000 (Direct Cost: ¥11,000,000)
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Keywords | Aerosol / Atmospheric General Circulation Model / Radiative Forcing / Data Assimilation / Climate Impacts / Single Scattering Albedo / 大気汚染 / 環境変動 / 気候変動 / ジメチルサルフェイト |
Research Abstract |
Aerosol radiative effects in East Asia were estimated for the present time (2000) and future (2 02 1) using an aerosol transport model, SPRINTARS and the CCSR/NIES atmospheric general circulation model (AGCM). The spatial distributions of various types of aerosols used were calculated by A03-P10 research group on the basis of the emission inventory database constructed by A03-P1 1 group. The results show that the total radiative effects in this area are almost in the same order as those presented by previous studies. However, the regional impacts are different in the northern and southern China ; namely strong cooling will occur in the northern part of China in future, but the cooling will be canceled out by warming effect of absorbing aerosols in the southern part of China. This contrast will be caused by the difference in spatial distribution of black carbon and sulfate aerosols. In order to estimate more precise optical properties of aerosols, model calculations were assimilated with satellite data. The results show that optimization of error estimation is necessary both for model calculations and satellite data to determining the precise weights of merging. Ground based observation data were also used to optimize the optical parameters adopted in model calculations. For example, refractive indexes used in model calculations were tuned based on the aerosol single scattering albedo (SSA) observed at Miyako-jima, an island in the south east Japan area, by A04-P13 group, and their impacts on model calculations were evaluated using AGCM. A new formula that describes relationships between the aerosol number concentration Na and cloud droplet concentration Nc was proposed by A04-P13 group based on laboratory experiments. AGCM calculations using the new formula show that the changes in Na-Nc relationship causes warming in high pollution area because of the decrease of cloud albedo due to the increase of cloud droplet size.
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Report
(5 results)
Research Products
(8 results)