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Urban air pollution is one of the most urgent problems to be solved in the process of China’s economic development and urbanization. Aiming at the spatial-temporal evolution problem of air quality in Henan province, this paper, based on the daily average data of urban air quality index of Henan province from 2014 to 2017, utilizes geostatistical analysis and spatial analysis methods to study the spatial and temporal distribution characteristics, as well as its evolution mechanism. The results show that: The urban air quality of Henan province is mainly Grade II and Grade III, there are obvious variations among cities, the air qualities of southern cities are significantly better than that of northern cities; From 2014 to 2017, the urban air quality has been gradually improved, the serious pollution process has been gradually reduced, the process duration has been gradually shortened, the air quality improvement in the southern cities is significantly better than that in the central and northern cities, but Luoyang in the western part of the province has gradually increased; the urban air quality shows seasonal distribution characteristics, autumn is the best season, from winter to autumn, air quality gradually improves. The urban air quality also presents the monthly distribution characteristics of low in the middle and high at two ends with a local extreme point in June, and August is the best month for air quality. The urban air quality index shows agglomeration characteristics, and the high value regions gradually shrink to the north, forming two heavily polluted regions centered on Zhengzhou and Anyang respectively. Keywords—Urban air quality; spatial distribution; spatialtemporal evolution; spatial aggregation; Henan Province

Spatial-Temporal Characteristics Analysis of Urban Air Quality and Its Evolution Pattern in Henan Province