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 (572KB)
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13,029,000Yen(FY1998; 4,403,000Yen)
To investigate how physical and biological interactions between the land surface ecosystems and the atmosphere influence the seasonal and interannual variations of atmospheric CO2 concentration in a regional scale, a numerical simulation using a physical regional climate model including a sophisticated biological land surface model was performed. The interannual variations of CO2 concentration computed by the model indicated the similar characteristics to those observed over Japan. It was suggested that in this experiment period the interannual variations of downward short wave radiation at the land surface were mainly responsible for the interannual variations of photosynthesis activities. The interannual variations of photosynthesis activities influenced the interannual variations of net CO2 flux between the land surface and the atmosphere, and those influenced the interannual variations of CO2 concentration in the lower troposphere over Japan(Meteorological Research Institute).
Carbon balance in Monsoon Asia was simulated using a regional model termed Sim-CYCLE which was based on the production theory established by Monsi and Saeki (1953)1). Terrestrial ecosystems of Monsoon Asia (land total 20.6 million km2; that is 150/0 of the global total land area; a spatial resolution of 0.5 degree longitude-latitude) are classified into 28 biome types. C4 plants occupy major parts of plant biomass in hot and arid grasslands, and thus they are discriminated from C3 plants, because of the large difference in physiological properties between the two plant types. Carbon fluxes such as gross primary production (GPP), net primary production (NPP) and net ecosystem production (NEP) were simulated by Sim-CYCLE(University of Tsukuba).
regional climate model, biosphere-atmosphere interaction model, CO2 flux,