MODELING OF POLAR STRATOSPHERIC CLOUDS
P(論文) Formation of polar stratospheric clouds (PSCs) is simulated assuming that they consist of H_2O ice particles. Stratospheric aerosols are assumed to work as the ice-forming nuclei if the supersaturation ratio exceeds the critical values determined from aerosol size. Growth of the PSC particles...
Main Authors: | , , , , , , , , , |
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Language: | English |
Published: |
National Institute of Polar Research
1991
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Subjects: | |
Online Access: | https://nipr.repo.nii.ac.jp/record/3653/files/KJ00000767856.pdf https://doi.org/10.15094/00003653 https://nipr.repo.nii.ac.jp/records/3653 |
Summary: | P(論文) Formation of polar stratospheric clouds (PSCs) is simulated assuming that they consist of H_2O ice particles. Stratospheric aerosols are assumed to work as the ice-forming nuclei if the supersaturation ratio exceeds the critical values determined from aerosol size. Growth of the PSC particles is computed using the condensation equations. Two cases of cooling rates of the atmosphere are tested. One is 1.0K/day, and the other is 0.25K/day. The number concentration of the PSC particles ranges between 0.1 and 0.4/(cm)^3,and the particle size ranges between 4 and 6μm. Further inspection shows that the particles are larger in number concentration but smaller in particle size when the larger cooling rate is used. A simulation is also carried out for the temperatures measured in the Antarctic winter of 1980 incorporating the fall effect of PSC particles. The result shows that growth of the PSC particles is restricted by the fall effect, particularly in the upper part of the PSC layer. departmental bulletin paper |
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