【摘要】 利用激光云高仪对2015年春天北京沙尘天气过程进行连续观测,结合常规地面气象要素、能见度和PM₁₀颗粒物质量浓度变化分析了两次沙尘天气过程中浮尘、扬沙和沙尘暴三类天气现象时气溶胶后向散射系数的时空分布特征,分析了云高仪后向散射系数与PM₁₀颗粒物质量浓度的相关性。结果表明:激光云高仪能够监测沙尘气溶胶粒子的时空变化,扬沙和沙尘暴期间后向散射系数随高度的增加而减小,后向散射系数在0.005 km^-1·srad^-1以上的沙尘层厚度约500 m;云高仪的近地面大气后向散射系数变化趋势与PM₁₀颗粒物浓度变化相同,10、50和100 m高度上的后向散射系数与PM₁₀颗粒物质量浓度的相关系数均在0.82以上。更多还原

【Abstract】 Continuous observation was made with the help of ceilometers on the sand-dust weather processes in Beijing in the spring of 2015.By using the observation data and the conventional ground meteorological elements,visibility and the changes of PM₁₀ particulate mass concentration,this paper analyzes the spatio-temporal distribution characteristics of aerosol backscatter coefficients in the three weather phenomena of floating dust,blowing sand and dust storm during the two sand-dust weather processes.In addition,the paper conducts the correlation analysis on the backscatter coefficient of ceilometers and the PM₁₀particulate mass concentration as well.The results indicate that ceilometers have the ability of monitoring the vertical distribution of aerosol particles.During the process of blowing sand and dust storm,backscatter coefficient decreases with the increase of height.What’s more,the correlation coefficients between the backscatter coefficient and PM₁₀ particulate mass concentration at the height of 10 m,50 m and 100 m are all above 0.82.更多还原