Spatiotemporal variations of ambient PM10 concentrations in nanchong, a big city of Southwest China

In order to further improve urban air quality, this study applied hourly PM10 mass concentrations in 5 monitoring stations during 2008-2012 to discuss spatiotemporal variations in Nanchong city, southwest China. The results showed that the annual mean PM10 concentrations during 5 years was 61.4μg/m3, and the concentrations order of 5 stations was JC (65.4μg/m3)>SW(64.6μg/m3)>JL(60.9μg/m3)>LY(60.4μg/m3)>GP(55.9μg/m3). The monthly mean concentrations in winter and spring were higher than in fall and summer. There was no obvious weekend effect in Nanchong and it was illustrated that the contributions to PM10 of vehicle exhaust could be smaller. The hourly concentrations were 54.8~68.1μg/m3 from 0:00 to 23:00 and the maximum appeared at 12:00 and 21:00 for each station. In addition, the influencing factors for PM10 were straw burning, fireworks and dust storms. The causes of these PM10 variations need to be studied deeply.