The overall aim of this part of the project (WP301 to 303) is to implement SI-traceable laboratory-based (round-robin) comparisons to verify the performance of reference irradiance and radiance sources and FRM OCR radiometers. This will include two laboratory-based intercomparison campaigns, one aimed at verifying the performance of radiance and irradiance sources used to calibrate ocean colour radiometers and the other aimed at verifying the performance of the radiometers themselves. Furthermore, the experiments require end-to-end uncertainty evaluation.
NPL is one of the world’s top national metrology institutes (NMI) and has taken a leading role in establishing a strong connection between metrology and Earth Observation. Its core roles include facilitating traceability to SI as well as the evaluation of uncertainty in measurement. Furthermore, NPL has pioneered many of the primary optical techniques now being used throughout the world, including the development of the cryogenic radiometer primary standard. By leading these core tasks of FRM4SOC, NPL will ensure SI-traceability, a detailed end-to-end uncertainty analysis that adheres strictly to the Guide to the expression of Uncertainty in Measurement (GUM-BIPM et al., 1995, JCGM, 2008) and thus a truly fiducial system that is underpinned by NMI reference standards.