Derivation of Hyperspectral Profile of Extended Pseudo Invariant Calibration Sites (EPICS) for Use in Sensor Calibration

摘要: Reference of Earth-observing satellite sensor data to a common, consistent radiometric scale is an increasingly critical issue as more these sensors are launched; such consistency can be achieved through cross-calibration the sensors. A common approach uses small set regions interest (ROIs) in established Pseudo-Invariant Calibration Sites (PICS) mainly located throughout North Africa. The number available cloud-free coincident scene pairs for limits usefulness this approach; furthermore, temporal stability most Africa not known, and limited hyperspectral information exists regions. As result, it takes time construct appropriate dataset. In previous work, Shrestha et al. presented analysis identifying 19 distinct “clusters” spectrally similar surface cover that widely distributed across Africa, with potential provide near-daily imaging This paper proposes technique generate representative profile clusters. was used cluster containing largest aggregated pixels. resulting found have uncertainties within 5% all spectral Overall, shows great generation profiles any African cluster, which could allow use entire Saharan region extended PICS (EPICS) dataset cross-calibration. should result increased resolution datasets help achieve quality individual significantly shorter interval. It also facilitates development EPICS based absolute calibration model, improve accuracy simulating sensor’s top atmosphere (TOA) reflectance.