2011~2014年气象要素对佛山市区PM_(2.5)浓度的影响

Impacts of Meteorological Factors on PM_(2.5) Concentration in Urban Regions of Foshan from 2011 to 2014

选取2011~2014年国控站点华材职中大气自动监测数据,研究影响佛山市城区PM2.5浓度的气象要素阈值区间。结果表明,当温度为15~25℃,湿度<45%,风速<3.3 m/s,风向为偏北风时,佛山城区PM2.5污染发生频率较高。引起PM2.5污染的天气形势大致分为高压出海型(34.2%)、弱槽弱脊型(26.3%)、锋面影响型(15.8%)、热带低压型(15.8%)和高压控制型(7.9%)。秋季和冬季PM2.5污染发生频次占比最大,热带低压型为秋季污染过程的主要天气型,弱脊弱槽型与高压出海型为冬季污染过程的主要天气形势。

The atmospheric automatic monitoring data were obtained from a state controlling air sampling site Huacaizhizhong from 2011 to 2014, in order to study the meteorological threshold ranges that affected PM2.5 concentration in Foshan city. The results showed that when the temperature was between 15~25 ℃, the humidity was below 43 %, the wind speed was below 3.3 m/s, the wind direction was northerly, the frequency of PM2.5 pollution in Foshan city was relatively high.The synoptic situation that caused PM2.5 pollution mainly included outflow-high-pressures(34.2 %), weak ridge-trough(26.3 %), front type(15.8 %),tropical-depressions(15.8 %) and subtropical-high-pressures(7.9 %). The frequency of PM2.5 pollution in autumn and winter accounted for the largest proportion.The main synoptic situation of the autumn pollution process was tropical-depressions. The main synoptic situation of the winter pollution process was weak ridge-trough and outflow-high-pressures.