Application of Satellite Remote Sensing in NOx Emission Control

: Tropospheric NO2 vertical column densities (VCDs) from ozone monitoring instrument(OMI) were analyzed to evaluate the decrease in NOx emissions during two special events, 70th anniversary of the end of World War Ⅱ in 2015 and the G20 summit in 2016. Results showed a positive correlation between NO2 VCDs and near ground NOx emissions and verified that the NOx emission control policy during "12th five-year plan" were remarkably effective, with a 24.98% drop in VCDs in five years. At the early stage of "13th five-year plan", in 2016, NO2 VCDs decreased by 3.18% year-on-year, showing a consistent drop in NOx.