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GPM SMAP Aura Suomi NPP

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Algorithm Theoretical Basis Documents

Algorithm Theoretical Basis Documents (ATBDs) have been developed for EOS instrument products, although some ATBDs address more than one product, and some products are addressed by more than one ATBD. ATBDs typically provide the theoretical basis, both the physical theory and the mathematical procedures and possible assumptions being applied, for the calculations that have to be made to convert the radiances received by the instruments to geophysical quantities. The geophysical quantities are then available to the scientific community for studies of the various characteristics of the Earth system.

NOTE: All ATBDs accessible through these links are subject to revision. These are the latest versions we are aware of. Please help us keep this list current by sending updates or other corrections to the web editor.