Abstract

The SENTINEL-2A mission, launched in June 2015, is dedicated to the observation of Earth’s land surface and coastal zones, especially the monitoring of land cover change and vegetation. The mission provides data continuity with both LANDSAT and SPOT programs, with increased resolution (down to 10m), revisit (10-day cycle for Sentinel-2A alone, 5-day cycle with Sentinel-2B to be launched in the end of 2016) and spectral resolution (13 spectral bands from 443 to 2190 nm). The Instrument is in-flight calibrated and characterized primarily using an on-board device (diffuser). Afterward, vicarious calibration methods are used in order to validate Sentinel-2A radiometry. The calibration can be checked over dedicated natural targets such as Rayleigh scattering, desert sites, Antarctica, and tentatively deep convective clouds. Based on these methods, it is possible to provide an accurate checking of many radiometric aspects such as absolute and interband calibrations, trending correction, calibration consistency within the field-of-view, and more generally this will provide an evaluation of the radiometric consistency for various types of targets. Another important aspect will be the checking of cross-calibration between many other instruments such as MERIS, MODIS (bridge to the GSICS radiometric standard), as well as the recently launched Sentinel-3 (bridge between Sentinel missions). The results of both nominal calibration over the on-board device and validation from vicarious methods, will be presented and discussed.

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Aug 23rd, 5:10 PM

Results from the Radiometric Absolute Calibration of Sentinel-2A

The SENTINEL-2A mission, launched in June 2015, is dedicated to the observation of Earth’s land surface and coastal zones, especially the monitoring of land cover change and vegetation. The mission provides data continuity with both LANDSAT and SPOT programs, with increased resolution (down to 10m), revisit (10-day cycle for Sentinel-2A alone, 5-day cycle with Sentinel-2B to be launched in the end of 2016) and spectral resolution (13 spectral bands from 443 to 2190 nm). The Instrument is in-flight calibrated and characterized primarily using an on-board device (diffuser). Afterward, vicarious calibration methods are used in order to validate Sentinel-2A radiometry. The calibration can be checked over dedicated natural targets such as Rayleigh scattering, desert sites, Antarctica, and tentatively deep convective clouds. Based on these methods, it is possible to provide an accurate checking of many radiometric aspects such as absolute and interband calibrations, trending correction, calibration consistency within the field-of-view, and more generally this will provide an evaluation of the radiometric consistency for various types of targets. Another important aspect will be the checking of cross-calibration between many other instruments such as MERIS, MODIS (bridge to the GSICS radiometric standard), as well as the recently launched Sentinel-3 (bridge between Sentinel missions). The results of both nominal calibration over the on-board device and validation from vicarious methods, will be presented and discussed.