Research Article
Analysis of SO2 Pollution Changes of Beijing-Tianjin-Hebei Region over China Based on OMI Observations from 2006 to 2017
Figure 5
Annual average SO2 column (DU) based on OMI (black circle dots) and SO2 emission statistics (blue asterisks) in (a) Beijing, (b) Tianjin, and (c) Hebei province (statistical data for 2017 have not been published).
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