This work evaluates the performance of OCO (Orbiting Carbon Observatory) −2 on global observations since its launch in Sep 2014. It is 10%∼30% coverage that could be detected to obtain the concentration of atmospheric carbon dioxide in space dimension. However, about 65% data of OCO-2 has not be utilized to retrieve because of special atmospheric environment, such as thick aerosol depth and low pressure. In the accuracy aspect, compared with the TCCON, OCO-2 has good consistence of XCO2 at most sites. The average bias of monthly value is about 0.87 ppm and the standard deviation is 1.8 over TCCON sites. The mean monthly value of CO 2  can represent the actual value at a certain range.
['Ailin Liang', 'Wei Gong', 'Ge Han']
OCO-2 XCO2 validation using TCCON data