Journal of Atmospheric and Environmental Optics ›› 2023, Vol. 18 ›› Issue (6): 553-568.doi: 10.3969/j.issn.1673-6141.2023.06.005

Previous Articles     Next Articles

Spatio-temporal variation and impact factors of tropospheric NO2 column density in Shaanxi-Gansu-Ningxia region based on OMI satellite data

WU Yarui*, WANG Hu, WANG Meijing   

  1. College of Geomatics, Xi'an University of Science and Technology, Xi'an 710054, China
  • Received:2022-02-22 Revised:2022-04-05 Online:2023-11-28 Published:2023-12-04
  • Contact: Ya-rui WU E-mail:wuyarui@xust.edu.cn

Abstract: In order to obtain the spatial and temporal distribution characteristics of NO2 and explore its pollution status, based on the tropospheric NO2 column concentration data from the Ozone Observation Instrument (OMI), and the corresponding meteorology, energy, traffic emissions and other statistical data, the temporal trends, spatial distribution characteristics and influencing factors of NO2 column concentrations in Shaanxi-Gansu-Ningxia region, China, from 2005 to 2019 were analyzed through geospatial analysis, linear fitting, correlation analysis and so on. The results show that the NO2 column concentrations in the past 15 years show a general trend of first rising and then falling. Seasonally, the variation of NO2 column concentrations presents as winter > autumn > spring > summer, with stable changes in summer and intense fluctuations in winter. In terms of spatial distribution, the high NO2 column concentration areas are distributed in the provincial capital and nearby regions, with the Xi'an urban agglomeration being the most obvious. Further analysis of influencing factors shows that topography and wind direction have a certain comprehensive influence on the spatial distribution of NO2. There is a significant negative correlation between temperature, rainfall and NO2 column concentration, indicating that high temperature and rainfall have a reducing effect on NO2 concentration. While coal consumption, industrial output value and motor vehicle ownership all show a positive correlation with NO2 column concentration, indicating that fossil energy combustion and motor vehicle exhaust emissions are important sources of NO2 in the region. The continuous decrease in NO2 column concentration after 2012 is deduced to be mainly related to the strong implementation of relevant national and local policies.

Key words: tropospheric NO2 column concentration, ozone monitoring instrument, Shaanxi-Gansu- Ningxia region, spatio-temporal distribution characteristics

CLC Number: