摘要
利用常规地面观测资料、探空数据、大气成分数据及垂直观测资料,对2016年7月28—30日北京市出现的一次雾霾天气过程进行分析。这次雾霾过程的天气形势是:北京地面受弱气压场控制,湿度较大,扩散条件较差,前期受500h Pa槽前偏南暖湿气流影响,有利于颗粒物的产生和增长,导致污染物累积,后期虽然有弱冷空气,但是700h Pa受暖平流影响,阻碍了高层冷空气向下侵入。推测此次污染受区域输送影响较大,PM_(2.5)浓度呈白天高、夜间低的日变化特征。利用云高仪测量大气混合层高度,发现雾霾发生时混合层高度明显降低,且低层后向散射强度大。混合层高度的变化特征对雾霾发展变化有着较好的指示作用,可为霾预报提供参考。
Using ground observation data, sounding data, atmospheric composition data and vertical observation data, a haze in Beijing in July 2016 was analyzed. The weather situation of the haze process was that ground was controlled by weak pressure field, and humidity was high, and diffusion conditions were poor. The weather was early affected by front southern warm moist air flows that resulted in the pollutant accumulation. Although there was a weak cold air later, but 700 hPa was affected by warm advection that hindered the upper cold air intrusion down-ward. It was speculated that the pollution was greatly influenced by regional transport. The cloud probe was used to measure atmospheric mixed layer height. It was found that the atmospheric mixed layer obviously decreased when haze occurred. Meanwhile, the scattering intensity was high. Therefore, mixing layer height variation characteristics of haze would be a better indicator of the changes of haze, which could be used to forecast haze.
出处
《环境科学导刊》
2018年第1期34-41,共8页
Environmental Science Survey
