不同天气状况下气溶胶散射系数变化特征分析

Variation Characteristics Analysis of Aerosol Scattering Coefficient in Different Weather Conditions

利用广州南沙区气象探测基地大气成分站2012年散射系数和常规气象观测资料,分析了散射系数的变化特征及气象因子对散射系数的影响,并重点讨论了气象条件中风对散射系数的影响。结果表明:从全年散射系数平均值来看,雾霾日的散射系数﹥霾日的﹥雾日的﹥一般日的;从季节来看,夏季和秋季雾霾日的散射系数﹥霾日的,冬季霾日的散射系数稍大于雾霾日的;一年中散射系数的最大值出现在10月,最小值出现在6月。霾日和雾霾日的散射系数日变化呈双峰形;雾日双峰型分布不明显,一般日没有明显日变化。散射系数同日照、湿度、气温和风速都呈负相关,与风速的负相关最显著。散射系数的高值出现在西北风中,外来源的输送对南沙散射系数存在较为明显的影响。风速小于7.0 m·s-1时,散射系数随风速的增加而减小;风速大于7.0 m·s-1时,散射系数随风速先增加后减小。

Based on the aerosol scattering coefficient and meteorological data collected in 2012 at Nansha Meteorological Observation Base, the paper analyzes the aerosol scattering coefficient variation characteristics and the influnce of meteorological elements, and focuses on the effects of wind on the scattering coefficient. The results show that the average scattering coefficient in fog and haze days〉 haze days 〉 fog days〉 general days, that in fog and haze days are greater than in haze days in summer and autumn, and scattering coefficient in haze days is a little larger than that in fog and haze days in winter. Scattering coefficient maximum value and minimum value appear in October and June respectively. Diurnal variation of scattering coefficient in haze and fog-haze days are double peak type, while that in fog and general days is not obvious. Scattering coefficient is negatively correlated with sunshine, humidity, temperature and wind speed, and the correlation with wind speed is the most obvious. High scattering coeficient value often appeares in the northerwestly wind flow, and the transportation of polluntants from outside significantly influences on the properties of aerosol of the regional background. Scattering coefficient increases as the wind speed decreases when wind speed in less than 7. 0 m· s -1 , while the wind speed is greater than 7. 0 m - s^ - 1 , the scattering coefficient increases first and then decreases with the increasing wind speed.