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 (2,126KB)
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53,088,000 Yen (FY1998; 14,235,000 Yen)
A chemistry coupled GCM (General Circulation Model) and a nudging CTM (Chemical Transport Model) are developed in order to understand ozone depletion mechanisms within and around the polar vortices. The chemical scheme and the chemical-radiative coupling scheme of the ID chemical-radiative coupled model that has been developed in NIES (National Institute for Environmental Studies) are modified for 3D model and introduced into the CCSR (Center for Climate System Research, University of Tokyo)/NIES AGCM (Atmosphere General Circulation Model). Gas phase reactions of Ox, HOx, NOx, and CIOx and heterogeneous reactions on NAT (nitrate trihydrate) and ice PSCs (Polar Stratospheric Clouds) have been introduced into the model successfully with model improvements on horizontal resolution and on oxygen molecule photolysis in the Schumann-Runge bands. The model results are compared to the TOMS and UARS observations. The comparison confirmed that the model results were realistic. The 03 and HNO3 distributions of the model around 70N in February and March 1997 are also compared to the ILAS data and SLIMCAT CTM outputs of Cambridge University. Ozone peak values of the CCSR/NIES chemistry GCM are a little higher and the peak altitudes are a little lower than those of the ILAS data and the SLIMCAT data. Peak values and peak altitudes of HNO3 are also different among these three data. Contributions of ozone transport and the ozone destruction chemistry in and around polar vortices during Ozone Hole were investigated by numerical experiments. A nudging CTM has also been developed based on the CCSR/NIES chemistry GCM.
Stratosphere, Ozone destruction, CCSR/NIES chemistry cooupled GCM, CTM, polar vortex