城市空气污染指数改进方案及论证

为进一步改进和完善我国城市空气污染指数(API),分析比较了国内外空气污染指数计算方法.提出了5种改进方案,这些改进方案均将计算时段调整为00:00—23:00.其中,方案1仅对计算时段进行了调整,方案2增加了CO和O3指标,方案3,方案4和方案5又增加了PM2.5指标,且ρ(PM2.5)限值依次加严.分别以新疆乌鲁木齐和广东广州2个城市的2009年空气质量监测数据对5种方案展开论证.结果表明:方案1和现行API差别不大;方案2对以煤烟型污染为主的乌鲁木齐市影响不大,但使广州市的空气质量超标天数增加,超标率达到36%,O3为首要污染物的天数占全年的比例达到43%,比现行API更好地反映了O3污染;方案3,方案4和方案5中优良天数明显下降,灰霾日空气质量超标率达到53%～89%,灰霾日中首要污染物为PM2.5的天数增加,上述方案能更好地反映我国东部发达地区面临的复合型空气污染状况.基于以上研究结果,提出了空气污染指数改进建议.

Schemes and Demonstrations for Air Pollution Index Improvement

In order to further improve and perfect the air pollution index(API) of China,various air pollution indices from within China and abroad were analyzed and compared.Five API improvement schemes were put forward.The calculation interval of the API was adjusted to 00:00-23:00 in all of the schemes.In the No.2 scheme,CO and O3 were added into the API.In the No.3-5 schemes,PM2.5 was added.The limit value of PM2.5 mass concentration was increasingly stricter from scheme No.3-5.The five improvement schemes were demonstrated using air quality monitoring data of Urumqi and Guangzhou in 2009.The results under the No.1 scheme were similar to the existing API.The results of the No.2 scheme had little impact on Urumqi,whose air pollution is mainly caused by coal burning.However,in Guangzhou,it made the number of days whose air quality exceeded the standard increase,reaching 36%.43% of days had O3 as the chief