Long-term cross-calibration of the Terra ASTER and MODIS over the CEOS calibration sites

The Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) and the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Terra satellite, which have different spatial resolution, can observe the earth surface simultaneously. Both of these sensors have been operated more than 10 years, and it is very useful for cross-calibration because of their simultaneous observations mostly without BRDF effect. On the other hand, the CEOS IVOS group arranges the CEOS reference standard test sites (instrumented sites and pseudo-invariant desert sites) for vicarious calibration and cross-calibration, which are able to evaluate the longterm stability among multiple sensors. This paper shows the TOA reflectance comparison between ASTER and MODIS sensor over the CEOS reference standard test sites.