Characterization of the atmospheric aerosol extinction based on the cavity ring-down spectroscopy.

Abstract

Abstract: Homemade laser cavity ring-down spectrometers (CRDS) were used to investigate the aerosol light extinction and the influence caused by relative humidity during a long term experiment around Kunshan. Observation results show that mean value of extinction coefficient is quite high, and a clear diurnal pattern was observed in extinction coefficient with maximum occurring at 7 a.m. and then dropped down to minimum at 5 p.m. The reasons are due to the great influence of the surrounding heavily polluted areas and the meteorological conditions. The observation results for the hydrophilic properties of atmospheric aerosol in the monitoring site show that atmospheric aerosol is hydrophilic type, and extinction coefficient is susceptible to the ambient relative humidity. The results of this study have certain guiding significance for the further study of the atmospheric aerosol properties of this area with aerosol mass spectrometry and other monitoring instruments.

Key words: relative humidity

References

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