常州市霾天气特征及其影响因子分析

基于常州市气象观测站2001-2013年的气象资料和大气自动站2009-2013年的监测数据，对常州市霾天气的变化特征、成因及其影响因子进行了初步分析。结果表明：2001-2013年，霾日数在全年及四季都呈现逐渐增多的年际变化特征，其中在2001-2008年，霾日数的趋势平稳且窄幅波动，但2009-2013年，霾日数急剧增加。季节变化上表现出夏季少、冬季多的分布特征。霾天气多发生在午后，11时出现的次数最多。常州霾天气持续日数不断增加，2013年连续霾日最长是16 d。常州霾典型天气形势为受冷高压或变性冷高压控制之下和处于入海高压后部或底部。常州霾天气受气象因子的影响，在静风、偏东风、50％～60％的相对湿度、逆温、降水偏少和大气湍流不利气象扩撒条件下都易形成霾。

Characteristics of Haze Weather and Factors Identification in Changzhou

The variation trend of haze and factors causing haze in Changzhou were analyzed based on meteorological observations obtained from Changzhou Meteorological Station （2001 -201 3 ）and atmospheric monitoring stations （2009-201 3 ）.The frequency of occurrence of haze had the following trends that the number of haze days in-creased gradually from 2001 to 201 3 .The number of haze days showed a slight rise from 2001 to 2009 .However, it increased sharply from 2009 to 201 3.Meanwhile,winter had more haze days than summer.Haze often occurred at noon with the highest frequency of occurrence around 1 1 o ’ clock in the morning.The number of continuous haze days has increased in Changzhou in recent years.The longest continuous haze days were 1 6 days in 201 3 .The typical weather conditions causing haze were the cold high-pressure or degeneration of the cold high pressure un-der control and in the rear or bottom pressure in Changzhou.The meteorological factors result in the occurrence of haze.Normally,haze often occurs with no wind or east wind,the relative humidity between 50%and 60%,inver-sion,less precipitation,and bad meteorological conditions for dispersal of pollutants.