Terra is the flagship of NASA’s Earth observing systems (EOS), carrying five sensors (ASTER, CERES, MISR, MODIS, and MOPITT), which have been providing high-quality global observations for nearly 15 years. MODIS has 20 reflective solar bands (RSB) and are calibrated using a solar diffuser (SD) with its degradation tracked by a solar diffuser stability monitor (SDSM). Scheduled lunar roll observations and vicarious data from pseudo-invariant sites are used to characterize the scanangle dependence of the MODIS RSB. The Multi-angle Imaging SpectroRadiometer (MISR) makes near simultaneous measurements with MODIS at nine view angles spreading out in the forward and backward directions along the flight path via four spectral bands (blue, green, red and near-infrared). MISR calibration efforts are based on a combination of preflight, onboard, and field vicarious measurements. This study compares coincident MODIS and MISR near-nadir reflectances over their entire mission, and examine the calibration stability and consistency of the two instruments. Reflectances from low to high signal levels are based on measurements obtained from ocean, desert and Antarctic snow surfaces. The absolute calibration differences between MODIS and MISR are examined after correction of their spectral response differences based on the SCIAMACHY measured hyperspectral data for the same sites.
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