Ozone Monitoring Instrument in-flight performance and calibration

The Ozone Monitoring Instrument (OMI) was successfully launched on board of the EOS AURA satellite on 15 July 2004. OMI is a hyperspectral sensor that measures in the wavelength range 264-504 nm with a spatial resolution of 13x24 km2 for wavelengths above 305 nm and 13x48 km2 below 305 nm. The 115 degrees instantaneous field of view covers about 2600 km at the equator, which enables daily global coverage of the Earth. In order to obtain the required quality of the level-1 (calibrated radiances and irradiances) and level-2 data products it is important to calibrate the instrument accurately both pre-launch and in orbit. This contribution presents the status of the OMI in-flight performance and calibration. The radiometric calibrations of the radiance and irradiance modes are discussed, including the dependencies on the elevation, azimuth and swath angles. The irradiance data are compared to literature reference data. The spectral calibration (accurate to about 0.01 pixel) and the spectral slit function calibration are also discussed and the in-flight correction to the spectral calibration for non-uniform ground scenes is discussed in detail. In addition, the current status of a number of detector and electronics parameters are presented.