In order to understand the spatiotemporal change of NO2 vertical column density in Beijing-Tianjin-Hebei region, the tropospheric NO2 vertical column density from 2005 to 2016 were analyzed by OMI remote sensing data from Aura satellite. The results showed that the spatial distribution of NO2 vertical column density in Beijing-Tianjin-Hebei region showed the decrease trend from the middle and southeastern plains to the northwestern Bashang plateau. The seasonal spatial distribution of NO2 column density was similar to the annual average distribution in Beijing-Tianjin-Hebei region during these twelve years. The average annual growth rate of NO2 density in Beijing-Tianjin-Hebei region was 2.66% with twelve years as one cycle. The NO2 density increased from 2005 to 2010, decreased sharply from 2014 to 2015, and increased in 2016. As for seasonal change, NO2 vertical column density values in autumn and winter were significantly higher than those in spring and summer. The highest NO2 densities appeared in winter and the lowest appeared in summer. Using linear fitting method, it was found that the density of NO2 column in Beijing-Tianjin-Hebei area was significantly correlated with the NO2 column density obtained by OMI sensor and the correlation was very high.

Key words：tropospheric NO2 density, OMI data, spatio-temporal change, Beijing-Tianjin-Hebei region