| Summary: | Over the past few decades, concentrations of carbon dioxide (CO<sub>2</sub>), a key greenhouse gas, have risen at a global rate of approximately 2 ppm/a. China is the largest CO<sub>2</sub> emitter and is the principle contributor to the increase in global CO<sub>2</sub> levels. Based on a satellite-retrieved atmospheric carbon dioxide column average dry air mixing ratio (XCO<sub>2</sub>) dataset, derived from the greenhouse gas observation satellite (GOSAT), this paper evaluates the spatial and temporal variations of XCO<sub>2</sub> characteristics in China during 2009−2016. Moreover, the factors influencing changes in XCO<sub>2</sub> were investigated. Results showed XCO<sub>2</sub> concentrations in China increased at an average rate of 2.28 ppm/a, with significant annual seasonal variations of 6.78 ppm. The rate of change of XCO<sub>2</sub> was greater in south China compared to other regions across China, with clear differences in seasonality. Seasonal variations in XCO<sub>2</sub> concentrations across China were generally controlled by vegetation dynamics, characterized by the Normalized Difference Vegetation Index (NDVI). However, driving factors exhibited spatial variations. In particular, a distinct belt (northeast−southwest) with a significant negative correlation (<i>r</i> < −0.75) between XCO<sub>2</sub> and NDVI was observed. Furthermore, in north China, human emissions were identified as the dominant influencing factor of total XCO<sub>2</sub> variations (<i>r</i> > 0.65), with forest fires taking first place in southwest China (<i>r</i> > 0.47). Our results in this study can provide us with a potential way to better understand the spatiotemporal changes of CO<sub>2</sub> concentration in China with NDVI, human activity and biomass burning, and could have an enlightening effect on slowing the growth of CO<sub>2</sub> concentration in China.
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