Validation of the OMI Surface UV data

Ozone Monitoring Instrument (OMI) onboard the NASA EOS Aura spacecraft is a UV/Vis spectrometer with a 2600 km wide swath capable of daily, global contiguous mapping. Mission requirements include monitoring of ozone and other trace gases, cloud pressure and reflectivity and aerosols. OMI is the successor to the NASA TOMS instrument but with 8-fold better ground resolution (13 by 24 km in nadir) and wide spectral coverage from 270 to 500 nm. The OMI measurements are used as inputs to the radiative transfer model to estimate the ultraviolet (UV) radiation reaching the Earth's surface. Noontime surface spectral UV irradiance estimates are produced at four wavelengths (305, 310, 324, 380 nm). Additionally, noontime erythemal dose rate and the erythemal daily dose are estimated. The OMI surface UV algorithm inherits from the TOMS UV algorithm developed by NASA/GSFC. We present the first OMI surface UV product validation results. We have compared the OMI UV data with other satellite UV products as well as ground based spectral UV measurement data. The results imply improvements in the accuracy of the satellite UV data thanks to the improved spatial resolution of the instrument.