Abstract:
The MODIS Surface Reflectance products provide an estimate of the surface spectral reflectance as it would be measured at ground level in the absence of atmospheric scattering or absorption. Low-level data are corrected for atmospheric gases and aerosols, yielding a level-2 basis for several higher-order gridded level-2 (L2G) and level-3 products.
MYD09CMG provides Bands
... 1–7 in a daily level-3 product gridded on a simple 0.05 degree (5600-meter) Geographic projection. Data for each pixel is selected on the basis of low solar zenith angle, minimum Band 3 (blue) reflectance, and absence of cloud from level-3 intermediate files. Science Data Sets provided for this product include reflectance values for Bands 1–7, brightness temperatures for Bands 20, 21, 31, and 32, solar and view zenith angles, relative azimuth angle, ozone, granule time, and quality assessment.
Version-5 MODIS/Aqua Surface Reflectance products are Validated Stage 2, meaning that accuracy has been assessed over a widely distributed set of locations and time periods via several ground-truth and validation efforts. Although there may be later improved versions, these data are ready for use in scientific publications. 
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