半干旱区气溶胶散射特性研究

Observational Study on Aerosol Scattering Properties in Semiarid Area

利用2005年1月至9月锡林浩特观象台积分浊度计的观测资料,结合同期的PM10质量浓度、能见度以及常规气象资料,分析了半干旱地区气溶胶的散射系数变化特征,讨论了它的季节变化、日变化、不同沙尘天气下气溶胶散射系数的变化情况,以及散射系数与PM10质量浓度、能见度的关系。结果表明1月至9月散射系数总体呈先下降再升高的趋势,日变化呈明显的双峰型;散射系数能很好的反映沙尘天气的强度;它与PM10质量浓度变化规律基本一致,两者之间具有很好的相关性;散射系数与能见度呈指数相关关系。

The aerosol scattering coefficient was measured with an integrating nephelometer at Xilinhot Observatory from January to September 2005, in combining with the mass concentration of PM10, the visibility, and the routine weather observation data a comprehensive analysis was conducted. We analyzed the seasonal and daily variation featuresof aerosol scattering coefficient. It is found that there is first a slow decline then an ascend from January to September, the daily variation of scattering coefficient presents a curve of bi-peaks. We also discussed the differences between different sand and dust weather. Result shows that the scattering coefficient increases when sand and dust weather occurs, and increases with the increasing sand and dust weather intensity. The scattering coefficient and mass concentration of PM10 have a high correlation coefficient. And there is an exponential relation between the scattering coefficient and the visibility. It proves that the scattering coefficient can monitor the sand and dust weather effectively under the measure precision with no high requirement.