A comprehensive radiometric validation protocol for the CERES earth radiation budget climate record sensors

The CERES Flight Models 1 through 4 instruments were launched aboard NASA's Earth Observing System (EOS) Terra and Aqua Spacecraft into 705 Km sun-synchronous orbits with 10:30 a.m. and 1:30 p.m. equatorial crossing times. These instruments supplement measurements made by the CERES Proto Flight Model (PFM) instrument launched aboard NASA's Tropical Rainfall Measuring Mission (TRMM) spacecraft on November 27, 1997 into a 350 Km, 38-degree mid-inclined orbit. An important aspect of the EOS program is the rapid archival and dissemination of datasets measured by EOS instruments to the scientific community. Six months after the commencement of science measurements, CERES is committed to archiving the Edition 1 Level 1 instrument, and Level 2 ERBE-Like data products. These products consist of geolocated and calibrated instantaneous filtered and unfiltered radiances through temporally and spatially averaged TOA fluxes. CERES filtered radiance measurements cover three spectral bands including shortwave (0.3 to 5 mum), total (0.3 to <100 mum) and an atmospheric window channel (8 to 12 mum). The current work summarizes both the philosophy and results of a validation protocol designed to rigorously quantify the quality of the data products as well as the level of agreement between the TRMM, Terra and Aqua datasets.