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Preflight Radiometric Calibration of Orbiting Carbon Observatory 2



Stephen Maxwell, B. Carol Johnson, Robert Rosenberg, Lars Chapsky, Richard A. Lee, Randy Pollock


This paper describes the prelaunch radiometric calibration of the imaging spectrometers used on the second Orbiting Carbon Observatory (OCO-2). The gain and dark response were characterized for each focal plane array detector element. An integrating sphere source with an integrated monitoring spectroradiometer illuminated the OCO-2 spectrometers at many light levels. Instrument output was compared to the calibrated output of the source to derive gain coefficients. This source was calibrated in situ with respect to NIST reference standards. Effects of environmental variability on dark offset were corrected following extensive testing. Solar spectra with varying neutral density filters were used to validate linearity of the spectrometers.
IEEE Transactions on Geoscience and Remote Sensing


Orbiting Carbon Observatory 2, satellite calibration, radiometry, global carbon dioxide concentrations


Maxwell, S. , Johnson, B. , Rosenberg, R. , Chapsky, L. , Lee, R. and Pollock, R. (2017), Preflight Radiometric Calibration of Orbiting Carbon Observatory 2, IEEE Transactions on Geoscience and Remote Sensing, [online],, (Accessed July 20, 2024)


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Created January 8, 2017, Updated October 12, 2021