The Analysis of NO₂ Concentration Changes and Removal Ability of Meteorological Factors

In order to understand the variation characteristics of NO₂ concentration and its influence factors, the time variation characteristics of NO₂ concentration and its relationship with influence factors were discussedusing the NO₂ monitoring data and meteorological data of Cangzhou between 2013 and 2018.The removal ability of the meteorological factors was mainly focused. The results showed that the average concentration of NO₂ was 41μg·m^-3 in Gangzhou, and the highest concentration in winter was 69.7μg·m^-3. The daily distribution showed "double peak and double valley" type, and there was an "anti-weekend effect" in which the weekend concentration was higher than weekdays. Through correlation and Grey correlation analysis, it was found that solar radiation, wind speed and NO₂ concentration had a significant correlation, while precipitation, solar radiation, wind speed and NO₂ concentration indicated the most significant correlation. According to the classified statistics, precipitation of different intensity, wind speed above 1.5m·s^-1, relative humidity below 40%, and moderate to strong solar radiation were very favorable for the removal of NO₂.