【摘要】 基于环境空气质量监测数据，本文分析了2022年6月14—18日高温热浪期间江苏省臭氧污染过程的时空变化特征，并结合天气形势、WRF-CMAQ模拟和典型城市大气超级站挥发性有机物（VOCs）在线监测数据进行了成因分析。结果表明：高温热浪期间，江苏省13个地级城市臭氧污染超标率达96.9%,中度污染超标率为27.6%,臭氧日最大8 h（MDA8 O₃）峰值质量浓度高达260.0μg·m^-3。南通市、无锡市、苏州市3个典型城市臭氧质量浓度的日变化特征显示，07—13时臭氧质量浓度增长率在27.9%～46.7%,多个时段净增量超过40.0μg·m^-3。利用WRF-CMAQ模型对污染过程进行了数值模拟、过程分析和溯源分析。结果显示，典型城市白天小时平均光化学贡献在24.5～33.0μg·m^-3之间，稳定高值的光化学贡献，叠加持续稳定或突发的传输贡献，导致此次高温热浪下臭氧质量浓度爆发式升高，出现峰值污染。在偏南风的影响下，省外污染源来自浙江省贡献最高，在13.9%～33.8%,其中无锡市和苏州市受浙江省外源影响较大。此外南通市大气超级站VOCs在线监测结果显示，臭氧污染期间逐日VOCs体积分数在45.5×10^-9～83.6×10^-9之间，整体处于高值水平，臭氧生成潜势（OFPs）贡献排名前十的物种以烯烃和芳香烃物质为主。更多还原

【Abstract】 Based on air monitoring data, this study analyzes characteristics of the ozone pollution episode during heat waves on June 14 to 18, 2022. Combined with synoptic situation, WRF-CMAQ model sensitivity experiments, and online monitoring data of Volatile Organic Compounds（VOCs） from urban atmospheric chemical super site, the study investigates mechanisms of the pollution episode. The results show that 96.9% of cities exceed O₃ pollution standards, 27.6% of cities exceed moderate standard, the peak of daily maximum 8-hour average O₃（MDA8 O₃） reaches 260.0 μg·m^-3. The ozone concentration growth rate during 07∶00 BST-13∶00 BST in heavily polluted cities of Nantong, Wuxi and Suzhou ranges from 27.9%-46.7%, with net increasing of more than 40.0 μg·m^-3 in several hours. According to WRF-CMAQ simulation results, daytime photochemical contribution in typical city is between 24.5-33.0 μg·m^-3. Stable and high photochemical contribution, combined with continuous or sudden transport contribution, leads to rapid increase of ozone concentration and emergence of peak pollution during heat waves. Under mainly southerly wind, emission sources outside the province come from Zhejiang with the highest contribution, ranging from 13.9%-33.8%. Wuxi and Suzhou are the most severely affected cities by Zhejiang pollution transport. In addition, online VOCs monitoring data from Nantong Atmospheric chemical super site performs that daily VOCs volume fraction is between 45.5×10^-9-83.6×10^-9 during ozone pollution, at a high level overall. The top 10 species of OFPs contribution are mainly olefin and aromatic hydrocarbons.更多还原