Research Article
Impacts of Chemical and Synoptic Processes on Summer Tropospheric Ozone Trend in North China
Figure 5
Time series of tropospheric column trace gas concentrations based on satellite observations for each summer during 2005–2016 in the NCP: (a) NO2, (b) HCHO, (c) SO2, and (d) CO. Each red line represents the fitting curve.
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