长江三角洲地区春季臭氧异常高值的数值模拟研究

已有的观测与研究表明,长江三角洲地区春季的臭氧浓度为全年最高,且高浓度臭氧出现的频率也最高.采用美国环境保护局(USEPA)的区域大气质量模式(CMAQ)研究长江三角洲地区2000年5月一次臭氧异常高值事件.与地面观测资料的对比分析表明,该模式基本再现了臭氧及其前体物的变化趋势.通过个例分析,从物理和化学两方面解释了2000年5月11日佘山、嘉兴和临安均观测到高浓度臭氧的原因.模拟结果表明,气象场对区域空气污染分布形式起着至关重要的作用,同时也反应了在适当的风场作用下,上海地区的污染源可以对长江三角洲地区的空气质量造成很大影响. 

Model Study of Springtime Abnormal High Level Ozone over the Yangtze Delta Region

The field measurements showed that the ozone concentrations over Yangtze Delta Region were highest in spring and high ozone concentrations were detected most frequently during spring time.The aims of this study are to reproduce the physical and chemical processes over Yangtze Delta Region using a regional air quality model,and explain the formation of the high concentration ozone in spring from physical and chemical aspects.The USEPA's community multiscale air quality (CMAQ) was applied to the Yangtze Delta Region,and one case of abnormal high ozone concentration in May 2000 studied.The model generally reproduces the temporal and spatial variations of ozone observed at the ground stations of the region.The causes of the high concentration observed at Sheshan,Jiaxing and Lin'an on May 11,2000 were analyzed.Modeling results indicate that meteorological fields have extremely significant effects on the distribution of the regional air pollutions.It is also found that with proper effects of wind field,the pollution source in Shanghai region could make a significant influence on the air quality of the Yangtze Delta Region.