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Carbon dioxide retrieval in thermal infrared band have to face the challenge that the signature of CO2 variations is small compared to spectral effects of temperature and water variability. Chahine et al. (2005) presented the method of vanishing partial derivatives (VPD) to retrieve CO2 and this method has been successful applied in the AIRS CO2 product. The VPD method has stricter criteria than Optimal Estimation (OE) method, and very small part of AIRS observation could be used for retrieval. We retrieved CO2 profile over East Asia by general OE method. The apriori profile is derived from EOF method, and the apriori covariance is derived from RAMS-CMAQ (Regional Atmospheric Modeling System and Models-3 Community Multi-scale Air Quality) incorporated VRPM (vegetation photosynthesis and respiration module). The validation was carried out by compared to CONTRAIL aircraft data and 9 surface stations in East Asia. A standard deviation of 2ppm compared to CONTRAIL aircraft was reached and a mean bias of 4 ppm was shown when compare retrieved XCO2 to surface CO2 from surface stations.