Dr. Kulawik has been extensively involved in the validation of satellite based CO2 retrievals, including AIRS, OCO-2, GOSAT, TES, and SCIAMACHY (Kulawik et al., 2016; Frankenberg, Kulawik et al., 2016; Worden, Doran, Kulawik, et al, 2016; Kulawik et al., 2013; Kulawik et al., 2010). Dr. Kulawik will advise on the biases and errors of the satellite based data and will characterize the relative biases between the different satellite datasets, utilizing the products produced by this proposal.