Fig. 9From: Spatiotemporal characterization of aerosols and trace gases over the Yangtze River Delta region, China: impact of trans-boundary pollution and meteorologyScatter plot between TROPOMI and in situ measurement of multiyear (2018–2021) monthly mean data of SO2 and NO2 over a Hangzhou, b Hefei, c Nanjing and d Shanghai. The results show that there is strong correlation among both datasets over all the citiesBack to article page