Analysis of the Variability of Atmospheric Visibility in Fengxian District of Shanghai Based on TDIC

Based on the meteorological monitoring data from 2008 to 2017 and air quality monitoring data in Fengxian District of Shanghai from 2015 to 2017, the relationships among the relative humidity (RH), and concentrations and visibility were explored emphatically by empirical modal decomposition (EMD), Hilbert spectral analysis and time dependent intrinsic correlation (TDIC). The results showed that the atmospheric visibility has obvious diurnal and seasonal variation characteristics, and the visibility has negative correlation with the change of relative humidity, and concentration, and the influence of particle concentration on atmospheric visibility is different at different relative humidity. Based on TDIC methods, the visibility is positively correlated with particulate concentration within the local time frame. The correlation changes will be affected by rainfall, wind speed, atmospheric pollutant concentration changes, extreme weather conditions and other factors. Through the above analysis, a better understanding of the variability of atmospheric visibility can be achieved.