Comparison of Atmospheric Nitrogen Dioxide Content Data Derived from Satellite (OMI) and Ground-Based (NDACC) Measurements

Comparison of satellite measurements with independent measurements is an essential and necessary component of validation of satellite data. In this work, we compare the spectrometric measurements of the NO₂ content in the atmosphere by the Ozone Monitoring Instrument (OMI) in 2004–2020 with the ground-based twilight zenith measurements at 14 stations of the Network for the Detection of Atmospheric Composition Change (NDACC). We obtained the latitudinal distributions of NO₂ content and of the comparison characteristics: differences in the contents and the correlation and linear regression coefficients between the satellite and ground-based data. Criteria are proposed for testing the interannual and long-term changes in NO₂ content derived from the OMI data based on the ground-based measurements. The latitudinal—hemispheric and regional—features of the correspondence between the satellite and ground-based data have been revealed. Significantly new results have been obtained on the dependence of the comparison characteristics on the level of pollution of the lower troposphere with nitrogen oxides and on the timescale of NO₂ variations: day-to-day, seasonal, and interannual. The results will be useful in the analysis of NO₂ variability based on OMI data.