北京冬奥会同期空气污染数值模拟

Air Pollution Numerical Simulation during the Same Period of Beijing Winter Olympic Games

第24届冬季奥运会将于2022年2月4—20日在我国北京市和河北省张家口市联合举办,主要会场有北京奥体中心、北京延庆县和张家口市崇礼县.为了模拟分析冬奥会空气质量情况,利用冬奥会同期(2006—2016年2月)北京市和张家口市空气质量资料及韩国气象厅天气图资料(2013—2016年2月),分析该时段重污染发生的频次,统计不利于污染物扩散的天气形势出现概率及污染传输路径,并结合嵌套网格空气质量预报模式(NAPQMS),评估不同减排方案对ρ(PM_(2.5))的影响.结果表明:(1)2006—2016年冬奥会同期,北京奥体中心和延庆县发生重污染天气的概率分别为17%和9%,污染发生的风险频率为北京奥体中心>延庆县>张家口市,并且北京奥体中心和延庆县在2月13—16日易出现持续的重污染天气过程;(2)2013—2016年2月不利于污染扩散的天气形势出现概率较为频繁,尤其在850 h Pa高度和地面,不利天气形势出现的概率分别为35%和41%;地面偏南风易将在北京西南方滞留较长时间的污染气团沿太行山输送至北京;(3)冬奥会期间,若于2月2—12日及17—20日将京津冀及周边城市污染物排放量在当前的基础上减排50%、2月13—16日减排75%,将可能不出现重污染日.严格控制北京及周边地区的大气污染物排放是保障冬奥会期间空气质量的必要措施.

The twenty-fourth Winter Olympic Games will be held from February 4th to 2 0 th, 2 0 2 2 , in Beijing and Zhangjiakou cities,China. The main venues will be at Beijing Olympic Sports Center and in Yanqing and Zhangjiakou. In order to simulate and analyze the air quality of the Winter Olympic Games, we used air quality monitoring data of Beijing in February in each year of 2006-2016 and weather map data from the Korean meteorological agency in February in each year of 2013-2016 to research the air quality situation during this period of the year. The frequency of heavy pollution in February in each year of 2006-2016 in Beijing was described, and the occurrence probability of synoptic situation not beneficial to contaminants diffusion and the transmission path of pollution were also analyzed. In addition, the effects of emission reduction schemes on concentration of PM2 5 were evaluated, combined with nested grid air quality prediction model （ NAPQMS ） . The results showed th a t： （ 1 ） During the same period as the Winter Olympic Games, the occurrence probability of heavy pollution at Olympic Center and Yanqing was 17% and 9% respectively. The risk of pollution in Olympic Center was the highest compared to Yanqing and Zhangjiakou, which faced the lowest risk. In addition, continuous heavy pollution easily occurred from February 13th to 16th in the past years in Olympic Center and Yanqing. （2） The synoptic situation which was not beneficial to contaminant diffusion appeared frequently in February in each year of 2013-2016, especially in 850 hPa and sea level synoptic, with frequency of 35% and 41% respectively. The ground southerly wind transported air pollution detained in southwestern Beijing to Beijing along Taihang Mountain. （3） If pollution emissions from Beijing, Tianj in, Hebei and surrounding cities can be reduced by 50% below current emissions from February 2nd to 12th and 17th to 20th in 2022, and reduced by 75% from February 13th to 16th , we predict that heavy pollution will not appear during the coming Winter Olympic Games. Thus, strict control of emissions from Beijing and its surrounding areas is a necessary measure to protect the air quality during the Winter Olympic Games.