It is essential that all measurements and associated instrumentation used for any quantitative purpose in remote sensing be fully traceable to SI as part of the Quality Assurance process.

This requirement was recommended by the Committee of Earth Observation Satellites (CEOS), which consists of members that represent the world’s governments that are responsible for Earth observation satellite programs and the agencies that receive and process the data acquired from those programs.

The members of the CEOS Working Group for Calibration and Validation (WGCV) submitted a selection of recommendations that were approved as part of the CEOS 14^th Plenary (2001).  The key recommendations were that:

• All EO measurement systems should be verified traceable to SI units for all appropriate measurands.
• Pre-launch calibration should be performed using equipment and techniques that can be demonstrably traceable to and consistent with the SI system of units, and traceability should be maintained throughout the lifetime of the mission.

These were later further reinforced at CEOS plenary 19.

The Optical Technologies group has, and is, engaged in all aspects of the Traceability Chain that provides the means to quality assure EO data products. The PDF below summarises some of key steps in this traceability chain for the optical spectral domain, their interdependencies and of course their traceability to SI through NPL’s primary standard.

Earth Observation Traceability Chain ( PDF 782 kB)

For further information, please contact: Nigel Fox