摘要(英) |
Abstract
This study is aimed to estimate the activation capacity of submicron aerosols and their radiation effect, based on CCN measurements. By means of theoretical approach and experimental operation of CCN counter, a set of microphysical thermodynamic equations describing the aerosol activation process in the cloud chamber was established.
During 22-28 May, and 7-9 June, 2000, the CCN counter was operated at the roof of the Central Weather Bureau (CWB) Building, Taipei. The measurements were further compared with air qualities, and also used to calculate activation ratio, microphysical properties including parameters C and k, and extinction coefficient of light scattering. The results are summarized as follows:(1)The concentration of submicron aerosol presented a diurnal variation, resulting from activities and meteorological variation. For example, washout effect significantly decreased the aerosol concentration.(2)There was a good correlation between total hydrocarbon and activation ability of the submicron aerosol in Taipei basin near the surface during measuring period.(3)During the observation period activation ratio of the sub-micrometer aerosol before noon is higher than that in afternoon.(4)Parameters C and k for our cases were consistency with the observations in previous studies. |
參考文獻 |
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