天津市西南地区PM_(2.5)污染及输送特征研究

Pollution and Transport Characteristics of PM_(2.5) in Southwest of Tianjin

静海区和西青区是天津西南界输送影响的关键区域,此研究基于2019年-2022年的PM_(2.5)观测数据和中尺度在线大气化学模式WRF/Chen的模拟数据,探讨区域输送对天津市西南地区PM_(2.5)的影响。结果表明,在不同的时间尺度上,天津市西南地区的PM_(2.5)污染都呈现冬季高、夏季低的规律,与天津市相比,天津市西南地区的PM_(2.5)污染较重。风速和风向都是影响天津市西南地区PM_(2.5)污染和重要因素。WRF/Chen的数值模拟结果表明,静海的PM_(2.5)的本地贡献远高于西青,静海和西青作为天津市的西南门户,周边区域的输送是其PM_(2.5)污染的重要来源,尤其是在秋末、冬季和主风向上,周边的廊坊、沧州、山东、北京和保定是静海和西青地区PM_(2.5)的关键源地。

The Jinghai Region and Xiqing Region are the key areas affected by the regional transport in the southwestern boundary of Tianjin.Based on PM_(2.5) data from 2019 to 2022 and the simulation data of the mesoscale online atmospheric chemistry model WRF/Chen,this study explores the impact of regional transport on PM_(2.5) in the southwestern region of Tianjin.The results showed that the PM_(2.5) pollution in southwest of Tianjin was higher in winter and lower in summer at different time scales.Compared with Tianjin,the PM_(2.5) pollution in southwest of Tianjin was more serious.Wind speed and wind direction are both important factors affecting PM_(2.5) pollution in southwestern Tianjin.The numerical simulation results of WRF/Chen Model show that the local contribution of PM_(2.5) in Jinghai is much higher than that in Xiqing.As the southwest gateway of Tianjin,the transport of PM_(2.5) in Jinghai and Xiqing is an important source of PM_(2.5) pollution,especially in late autumn,winter and the main wind direction.The surrounding Langfang,Cangzhou,Shandong,Beijing and Baoding are the key sources of PM_(2.5) in Jinghai and Xiqing.