河北廊坊重污染天气特征及气象条件影响研究

Characteristics of Heavy Pollution Weather and Influence Meteorological Conditions in Langfang,Hebei Province

利用2013—2016年廊坊市环境监测数据以及同期相关气象资料,采用数理统计等方法,研究重污染天气特征及影响的气象条件.结果发现:空气质量达标天数呈逐年上升趋势,而重污染天数逐年下降;重污染天气主要出现在1—3月、10—12月;重污染天气首要污染物只有PM10、PM2.5、O3与PM10,PM2.54种情况.重污染天气日气象要素特征明显:主导风向主要位于风玫瑰图的第一、第三、第四象限,风速基本上小于1.6 m/s;相对湿度多在50%以上;年均能见度小于10 km;1—3月、10—12月主要污染月逆温层厚度更厚,强度更强,逆温出现频率也更高;静稳天气指数除了4、5、7月小于10以外,其余月均大于等于10;3—6月混合层高度在1000 m以上,其余月小于1000 m;重污染日霾、雾、轻雾、露、霜、结冰6种天气发生的频率较高.

Based on environmental observation data and meteorological observation data in Langfang of Hebei Province during 2013-2016,characteristics and influence of meteorological factors for heavy pollution are studied by using mathematical statistics.The results show that the numbers of days reached the standard increase year by year,while the numbers of heavy pollution days decrease year by year.Days for heavy pollution mainly occur during January-March and October-December.Primary pollutant for heavy pollution have PM10 and PM2.5 and O3 and PM10,PM2.5.Characteristics of meteorological factors for heavily pollution weather is obvious.Dominant wind direction is mainly in the first,third and fourth quadrants of wind rose plot.Wind speed is mostly less than 1.6 m/s,and relative humidity is mostly above 50%.Annual visibility is less than 10 km.Inversion layer is generally thicker,and inversion intensity is stronger,and inversion frequency is higher during January-March and October-December.In addition to April,May and July,static weather index is more than 10 in other months.Mixed layer height is above 1000 meters during March-June,and it is less than 1000 meters in other months.Occurrence frequency of six weather phenomena for haze,fog,light fog,dew,frost and freeze is higher in heavy pollution days.