The OMI Earth Surface Reflectance Climatology product, OMLER (Global 0.5 degrees Lat/Lon grid) which is based on Version 003 Level-1B top of atmosphere upwelling radiance and incoming irradiance. OMI calibrated and geolocated radiances from 159 channels in UV1(264-311 nm), 557 channels in UV2 (307-383 nm) and 751 channels in VIS (349-504) spectral regions, spectral irradiances, calibration measurements, and all derived geophysical atmospheric products (Level-2 and 3) are archived at the NASA Goddard DAAC.

OMLER spectral surface reflectance product contains monthly and yearly climatology of the Earth's surface Lambert Equivalent Reflectance (LER) for 23 wavelengths in the spectral range 309 to 500 nm, at a spatial resolution of 0.5 by 0.5 degrees. This LER is defined as the required reflectance of an isotropic surface needed to match the observed top of the atmosphere (TOA) reflectance in a pure Rayleigh scattering atmosphere under cloud free conditions and no aerosols. The climatology is based on statistical analysis of the three years of OMI version 03 radiance data (Oct 2004-Oct 2007). This product also provides minimum spectral surface reflectivity observed during the three year period.

The OMLER product file is produced in the version 5 Hierarchical Data Format (HDF-EOS5). It is roughly 300 MB in size.