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The Metrological Basis for MOBY



Bettye C. Johnson


The Marine Optical BuoY (MOBY) is a primary source of data for System Vicarious Calibration (SVC) of ocean color satellite sensors. I will present brief introduction to SVC followed by a short history of MOBY and the main features of its instrumentation and operation. MOBY has been closely tied to our NMA (NIST), and how we have maintained the concept of metrological traceability and SI-traceability will be described. Determining the uncertainty of the data set is fundamental in the FRM construct, and I will discuss our current understanding of the uncertainties in our measurements and the status of reprocessing efforts to remove identified sources of bias and assign uncertainty estimates to additional components. Our quality control and data maintenance will also be described. Finally, I will conclude with an update on the replacement of the heritage MOBY design with the new system, MOBY Refresh, as well as MOBY NET, which is aimed at future opportunities for ocean color SVC.


Ocean Color, Marine Optical Buoy, Uncertainty


Johnson, B. (2018), The Metrological Basis for MOBY,, [online], (Accessed May 26, 2024)


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Created December 20, 2018, Updated January 31, 2019