中文摘要：

2013年中国东部地区多次发生持续的重霾污染事件.为探究其气象条件与重污染事件的关系,本文使用欧洲中心2013年东亚地区的逐日气象数据和北京、天津、石家庄的逐时PM2.5浓度数据以及2013年MICAPS观测数据,分析了重污染事件对应的天气形势,并使用NAQMPS针对2013年1月的重污染事件进行情景模拟.研究结果表明：（1）北京、天津和石家庄地区PM2.5浓度,夏秋季节日变化不显著,秋冬季节白天低夜间高;3地PM2.5浓度均表现为12—1月浓度最高,7月最低;.（2）500 hPa平直西风气流,850 h Pa弱暖平流,地面处于弱高压后部或高压底部高低空配置下的天气系统,对应着重污染事件的高发期;（3）源强不变的情况下,京津冀地区由弱高压前部控制转为弱高压控制时,地面温度升高0~5°C,相对湿度增加30%~50%,风速下降2~3 m·s-1,PM2.5浓度变化可达300μg·m-3.

英文摘要：

Eastern China has suffered severe and continual haze pollution.The meteorological condition which is very important to influence the formation and depletion of the air pollution has been investigated based on the data from European Centre form Medium-Range Weather Forecasts（ECMWF）,Meteorological Information Comprehensive Analysis and Process System（MICAPS） and Chinese Network of Environmental Monitor Center（CNEMC） in this study.Besides,the Nested Air Quality Prediction Model System（NAQPMS） was used to simulate the severe haze events occurred in January 2013.The results showed a significant seasonal change of diurnal concentration of PM2.5 in summer and autumn.The maximum and minimum monthly averaged concentrations were observed in January and July,respectively.Westerly flow in 500 h Pa and weakly warm advection stabilized the atmospheric stratification and impaired the diffusivity of pollutants on the surface,especially when Beijing-Tianjin-Hebei Area was in the back or bottom of weak anticyclone on the surface.Furthermore,NAQPMS quantified this effect that when temperature increased by 0~5 ℃relative humidity increased by 30%~50% and wind decreased by 2~3 m·s-1,PM2.5 concentration increased by 300 μg·m-3.