Temporal and distribution characteristic of CO<sub>2</sub> concentration over China based on GOSAT satellite data

Abstract

Atmospheric CO2 concentration over China has significant effects on the global climate change. To reliably predict the impact of atmospheric CO2 on global climate change, it is necessary to clarify the distribution and variation of atmospheric CO2 concentration. Based on long term short-wavelength infrared CO2 dataset observed by GOSAT, the temporal variation and spatial distribution characteristics and variation trend of atmospheric CO2 concentration was investigated and analysed over China during 2010 to 2016. To ensure the quality of GOSAT CO2 dataset used in this paper, the GOSAT XCO2 dataset was validated with high precise XCO2 from ground-based TCCON sites.Multi-year mean of XCO2 was illustrated to show the spatial heterogeneity of CO2 concentration over China. Interannual variation and annual growth of XCO2 was also presented and discussed. The results showed that GOSAT XCO2 dataset was biased by-1.04±2.10 ppm with respect to TCCON XCO2, and the correlation coefficient was 0.90 between them. Seven years(2010~2016) of GOSAT CO2 dataset showed that high CO2 concentrations were mainly located in Zhejiang-Jiangsu-Anhui region, Beijing-Tianjin-Hebei region, and HunanHubei-Henan-Shanxi region in China. The CO2 concentration reached 400 ppm over most regions in China until 2016. The annual average of CO2 concentration showed an increase trend year by year over China, increasing from 387.76 in 2010 to 402.18 ppm in 2016. The annual growth rate of CO2 concentration was evaluated to be 2.31 ppm/a during this period over China, which was slightly higher than the average in the world. This paper shows that the CO2 concentration observations from satellites could provide some references for the climate change response strategies and atmospheric environment control.