Urban Atmospheric Environmental Quality Evaluation Based on Grey Correlation Analysis: A Case Study on Municipalities Directly under the Central Government and Provincial Capitals

With the acceleration of urbanization, urban atmospheric pollution is becoming severe. Urban atmospheric environmental quality evaluation has aroused broad attention. This paper introduced grey correlation analysis into evaluation of urban atmospheric environmental quality and established an evaluation model. The paper selected PM10, SO2, NO2 and days of air quality equal to or above grade II as evaluation indexes. Finally the paper developed a case study on the four municipalities directly under the central government and the twenty-seven provincial capitals. The calculation results show that atmospheric environmental qualities of the 31 cities are not good, especially the four municipalities. Additionally, the paper compares results of grey correlation analysis method with that of fuzzy matter-element method. The concept of grey correlation analysis is clear and the calculation process is convenient, so grey correlation analysis is applicable to evaluation of atmospheric environmental quality.