Carbon monoxide vertical column density retrieval from SCIAMACHY infrared nadir observations

Abstract. Nadir observations in the shortwave infrared channels of SCIAMACHY onboard the ENVISAT satellite can be used to derive information on CO, CH4, N2O, CO2, and H2O. BIRRA (Beer InfraRed Retriaval Algorithm) is a nonlinear least squares fit of the measured radiance: Trace gas vertical profiles are scaled to fit the observed data, further auxiliary parameters are code dependent. Here we discuss some features of the code and present results of carbon monoxide vertical column densities retrieved from SCIAMACHY infrared nadir observations