Abstract:
Based on the monthly air quality index (AQI) data and meteorological data from 2014 to 2017, statistical analysis, pearson correlation coefficient method and generalized additive model (GAM) were used to analyze the time variation of air quality index and its relationship with meteorological elements in Xinyang urban area. The results were as follows: (1) from 2014 to 2017, the annual fluctuation of AQI in Xinyang urban area was relatively large, and the air quality showed an increasing trend in general. During the study period, the air quality in Xinyang urban area was good for 27 months (56.25%), light pollution for 19 months (39.58%), and moderate or severe pollution for 2 months (4.17%). Air quality in Xinyang urban area had obvious seasonal characteristics, with air quality from good to poor in turn: summer, autumn, spring and winter; (2)The AQI generally showed remarkable negative correlation with the temperature, average vapor pressure, average relative humidity, sunshine duration and wind speed, while it showed positive correlation with air pressure. The correlation between meteorological elements and AQI showed a large difference in different seasons and different levels of air quality; (3)The AQI value from GAM showed a linear correlation with the precipitation and nonlinear correlation with other relative meteorological elements. The impact of meteorological elements on AQI generally had a threshold.