Relationship between visibility and relative humidity, PM10,PM2.5 in Tianjin
Based on the visibility data in 2009 and relative humidity (RH), concentrations of PM10 and PM2.5 in Tianjin, their relationships were analyzed.The results indicate that the linear correlation coefficient between RH and visibility is the highest and that between PM2.5 concentration and visibility ranks second.The visibility decreases obviously with the increase of RH.When RH is less than 60％, there exists a significant nonlinear correlation between the visibility and PM2.5 concentration and a weak correlation between the visibility and PM10 concentration,while the correlation between the visibility and the concentration difference between PM10 and PM2.5 is not significant.When RH is greater than 60％ ,the nonlinear correlation between the visibility and PM10 concentration is more significant than that between the visibility and PM2.5 concentration.The nonlinear correlation efficient between the visibility and RH is higher than their corresponding linear correlation efficient.Finally, a nonlinear fitting formula of visibility in Tianjin is developed using RH,PM10 and PM2.5.It has been shown through examination against the observation that this formula is able to simulate the visibility in Tianjin with a relatively good accuracy.
国家科技期刊平台
NSTL
万方数据
维普
