Spatial and Temporal Distributions of Atmospheric CO2 in East China Based on Data from Three Satellites

East China (113.6°E~122.9°E, 23.6°N~38.4°N) is the largest developed region in China. Based on CO2 products retrieved from GOSAT, the temporal and spatial distribution of CO2 mixing ratios in East China during 2014−2017 were discussed, and the retrieved CO2 from AIRS, OCO-2 and WLG (Waliguan) background station observation were compared with that of GOSAT. The annual CO2 retrieved from GOSAT in East China ranged from 398.96±0.24 ppm in 2014 to 407.39±0.20 ppm in 2017, with the growth rate of 2.82±0.15 ppm per year, which were higher than the other six regions in China. The seasonal cycle presented a maximum in spring and a minimum in summer or autumn. Higher values were mainly concentrated in the coastal areas of Zhejiang Province, and lower values were concentrated in Jiangxi and north of Fujian Province. CO2 observed in Fujian and parts of Jiangxi increased less than 1.0 ppm during 2014−2015, but enhanced significantly more than 5.0 ppm during 2015−2016, perhaps influenced by local emissions and global impacts. We calculated year-to-year CO2 enhancements in Yangtze River Delta regions during 2014−2017 that were relatively low and stable, due to its carbon emission control and reduction policies. The annual and seasonal amplitude of CO2 retrieved from AIRS were lower than that from GOSAT in East China, probably owing to CO2 retrieved from AIRS better reflected the characteristics of mid-troposphere, while GOSAT reflected the near-surface CO2 relatively. The spatial and temporal distribution characteristics of CO2 retrieved from OCO-2 were close to that from GOSAT in East China.