河北重度污染天气分型及其气象条件特征

Weather Classification of Heavy Pollution in Hebei Province and Its Meteorological Condition Analysis

利用2013—2016年河北省196个环境观测站资料和气象资料对河北省易出现重污染的天气形势进行天气学分型:辐合型、回流型、均压场型、高压后部型、西北高压型、北高型,其中西北高压型出现频率最高,均压场型次之,回流型出现频率最低。通过对河北省3个代表站2014—2016年秋冬季混合层高度、静稳天气指数及小风日数与污染物浓度的统计,分析得到3种指数与大气污染有很好的相关性,即混合层高度越低、静稳天气指数值越大、小风日数越多,越容易出现空气污染。另外通过对比不同类型重污染天气下混合层高度和静稳指数数值,得出天气分型与气象特征量的对应关系:北高型最稳定,西北高压型最容易被破坏。

The observations from 196 environmental observation stations and meteorological data during 2013-2016 were used to classify weather situation that was prone to occurring heavy pollution in Hebei Province,then six weather types including convergent type,returning flow type,uniform pressure field type,high pressure rear type,northwest high pressure type and north high pressure type were given,among them,the northwest high pressure type appeared most frequently,then followed by uniform pressure field type,while returning flow type occurred least. Based on the statistics of mixed layer height,static stability weather index,breeze days and air pollutant concentration from three representative stations of Hebei Province in autumn and winter during 2014-2016,it was showed that there was a good correlation between air pollution and three indexes,when mixed layer height was lower,the static stability weather index was higher and breeze days was more,there would be more conducive to the formation of air pollution. In addition,through comparing the height of the mixed layer and the static stability weather index under different weather types when heavy pollution occurred,the corresponding relationship between weather types and meteorological characteristic was obtained. The north high pressure type was most stable,while northwest high pressure type was likely to be destroyed.