中文摘要：

利用地面气象要素、火点信息及污染物资料,研究了2014年6月12～13日湖北省中东部地区一次重度霾天气的成因及污染特征。结果表明：导致此次霾天气的主要原因是安徽省北部大面积秸秆焚烧所形成污染气团受偏东北气流输送的影响,12日在湖北中东部形成了两条＂带状＂的能见度低值区,最低能见度仅为2.1 km。秸秆焚烧污染物输送气流由北向南影响湖北,主要作用于孝感—武汉—咸宁一带,3个地区细颗粒物（PM2.5）峰值浓度均超过了600μg/m^3,且武汉和孝感的PM2.5与PM10质量浓度比值在12日增加到0.76和0.77,并出现了0.96和0.93的最大值,随着污染气团的传输,其中PM2.5所占比例会出现明显下降。SO2质量浓度的变化特征不显著,NO2质量浓度在污染物质量浓度达到峰值前1～3 h达到峰值,而CO是秸秆焚烧产生的主要污染气体,其质量浓度变化与PM2.5和PM10呈正相关关系,相关系数分别为0.66和0.67。风矢量和分析表明：6月12日湖北省中东部存在明显的东北来向气流输送,污染物的输送是该时段霾天气发生的主要影响因子,而6月13日湖北省东北边界处的输送气流已经明显减弱消失,东南部风矢量和异常偏小导致的污染物堆积是该地区污染持续的主要原因。

英文摘要：

Based on surface meteorological parameters, fire spot information, and air pollutant concentrations, a serious haze event that occurred in central eastern Hubei Province during 11–12 June 2014 was investigated. The dominant reason for this air pollution episode was pollutants being released from crop residue burning in the northern regions of Anhui, and then combining with favorable transport flows. Two zones with low visibility formed in eastern areas of Hubei, with the lowest value of daily average visibility being just 2.1 km. The pollutants released from crop residue burning influenced the air quality of Hubei from north to south, playing a major role in areas around Xiaogan, Wuhan, and Xianning, with peak values of PM2.5 concentration of more than 600 μg m-3 in these three cities. The ratios of the mass concentrations of PM2.5 and PM10 increased to 0.76 and 0.77 in Wuhan and Xiaogan on 12 June 2014, and reached maximum values of 0.96 and 0.93, respectively. With the transmission of polluted air mass, the proportion of PM2.5 decreased significantly. The variations of mass concentration of SO2 were negligible, while the mass concentration of NO2 reached its maximum value 1–3 hours before the PM2.5 or PM10 reached their maximum values. CO was the main gas pollutant produced by crop residue burning, which was positively correlated with the concentrations of PM2.5 and PM10, with correlation coefficients of 0.66 and 0.67, respectively. By analyzing the wind using the Vector Sum Technique（VST）, it was found that the air flow in central eastern areas of Hubei transported from the heavily polluted regions（northeast to Hubei Province） was significant. The transportation of pollutants was the main factor causing the occurrence of the haze event on 12 June, while the transportation was weakened markedly on 13 June. The small VST value of wind speed in the southeast of Hubei caused pollutants to accumulate, promoting the continuation of the haze event.