天气条件对成都市夏季臭氧持续污染的影响分析

Analysis of the Influence of Weather Conditions on Persistent Ozone Pollution in Chengdu in Summer

摘要: 通过统计2014~2017年4~10月成都市9个环境监测站点的O₃、NO₂、CO、PM_2.5的监测资料以及气象观测资料，分析了这四年成都市臭氧持续污染特征，对比分析了成都市城区和清洁对照站点臭氧浓度和气象要素的关系，并以2016年典型个例分析了天气条件对成都市夏季臭氧持续污染的影响。结果表明：成都市臭氧污染与3天以上臭氧持续污染事件多发生在5月和7月；臭氧持续污染与天气系统密切相关，持续污染过程中臭氧浓度与温度呈现明显的正相关；持续高温(日最高气温30℃以上)、较低湿度、晴朗少云天气、无降水、小风速、西风、西北风对成都市臭氧持续污染有利；夏季副热带高压的西伸和维持造成的持续高温天气对成都及周边城市臭氧持续性污染有重要影响。

Abstract: Based on the monitoring data of ozone, NO₂, CO and PM_2.5 at 9 environmental monitoring stations in Chengdu from April to October in 2014-2015, and the meteorological observation data, the continuous ozone pollution in Chengdu in the past four years was analyzed. Comparison analysis of ozone concentration and meteorological factors was conducted for urban area and contrast station of Chengdu. A typical ozone pollution episode in August 2016 was selected and studied in detail. The main conclusions are as follows: ozone pollution days and the continuous pollution events were the most serious in July and May. Continuous ozone pollution is closely related to the weather system. There was a significantly positive correlation between ozone concentration and temperature during the continuous pollution processes. Continuous high temperature (daily highest temperature above 30˚C), low humidity, sunny to low cloud weather, no precipitation, small wind speed, westerly and northwest wind were favorable for continuous ozone pollution in Chengdu, subtropical anticyclone moved westward causing high temperature in Sichuan Basin and played an important role in continuous ozone pollution in Chengdu and surrounding areas.