Analysis of the Bias of GOSAT XCO₂ Data at TCCON Observation Sites

To evaluate the bias of GOSAT XCO₂ data, differences between GOSAT and TCCON XCO2 data (ΔXCO₂) were analyzed at three TCCON sites. ΔXCO2 of GOSAT FTS SWIR L2 CO₂ Product V02.72 showed high correlation with the difference between retrieval and reference surface pressure (ΔPS). As for V02.75, the bias-corrected version of V02.72, significant XCO₂ biases remain at two of three sites. These biases must be corrected in order to estimate carbon flux precisely by synthesis inversion method