Research on Density and Diffusion Trajectory of NO2 during Heavy Pollution Period in Urumqi
LIU Yan
LI Yanhong
HOU Xiaogang
MA Wen
Abstract：How to quickly and effectively obtain the temporal and spatial distribution of pollutants under heavy pollution and analyze its causes,is very important to solve the problem of air pollution in China.In this study,based on the multi axis differential optical absorption spectroscopy (MAX-DOAS),inversion of the vertical column density (VCD) of tropospheric NO2 in Urumqi from February to March in 2016 was carried out,and the meteorological factors and atmospheric background field were analyzed.The results showed that the average tropospheric of NO2 VCDs on February 16th,2016 in Urumqi was 26.89× 1015 molec/cm2 and it was 21.21 ×1015 molec/cm2 on March 17 th.High values were usually found near traffic nodes like viaducts.Average NO2 emission flux in February and March were 1.11×103 kg/h and 0.73×103 kg/h,respectively.There was a negative correlation between wind speed and NO2 VCDs during heavy pollution.2 m/s and above wind speed and NO2 VCDs decision coefficient (R2) is 0.40.And the downwind NO2 density was usually higher than the windward value.Wind direction and terrain elements of the superposition,are more likely to produce differences in NO2 concentration.The Hysplit model retrieved the diffusion trajectory and found that during heavy pollution period in Urumqi the atmospheric pollutants travelling with airflow from nonlocal areas were less than local sources,which were predominant.Airflow influenced local pollutant densities mainly by carrying and diluting.
Keywords：heavy pollutionmobile MAX-DOASspread trajectoryUrumqi
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 33-39 )