STUDY ON COMPARING RANKING METHODS OF AMBIENT AIR QUALITY IN URBAN AREA

This paper analysed and compared some conventional air quality ranking methods，including composite index， maximum index，Nemerow index，air quality compliance rate，major pollutant concentration，weighted composite index based on AHP methods and so on． Results showed that the composite index and weighted composite index both could consider contributions from all kinds of air pollutants，had well comparability for all cities，and reflected the differences between air quality in cities subjectively and accurately． The two methods were suitable for ranking the cities according to their own air quality at present．