The column mean concentration of carbon dioxide has been retrieved using WFM-DOAS algorithm, developed at Bremen University, Germany from data obtained with a SCIAMACHY spectrometer installed onboard Envisat satellite. The obtained data are compared with airborne measurements carried out in 2003 over two regions of Western Siberia, Surgut and Novosibirsk. The retrieved time behavior of CO2 concentration during warm periods is in a good qualitative agreement with data of airborne sensing while being seriously underestimated in the presence of snow cover. Some possibilities of improving accuracy of the WFM-DOAS algorithm are discussed.