Copernicus Sentinel-2A Calibration and Products Validation Status

Abstract

As part of the Copernicus programme of the European Commission (EC), the European Space Agency (ESA) has developed and is currently operating the Sentinel-2 mission that is acquiring high spatial resolution optical imagery. This article provides a description of the calibration activities and the status of the mission products validation activities after one year in orbit. Measured performances, from the validation activities, cover both Top-Of-Atmosphere (TOA) and Bottom-Of-Atmosphere (BOA) products. The presented results show the good quality of the mission products both in terms of radiometry and geometry and provide an overview on next mission steps related to data quality aspects.

A Global Analysis of Sentinel-2A, Sentinel-2B and Landsat-8 Data Revisit Intervals and Implications for Terrestrial Monitoring

“…For example, Landsat-8 does not acquire data over oceans and acquires 725 scenes per day out of a global average of 810 possible land scenes [27]. Similarly, the Sentinel-2 satellites will systematically acquire observations over land and coastal areas from −56 • to 84 • latitude including islands larger 100 km 2 , all the European Union islands, the Mediterranean Sea, and all inland water bodies and closed seas [28]. Future research to quantify the acquisition sensor frequencies considering the Landsat-8, Sentinel-2A and Sentinel-2B data archive and the degree of cloudiness when a global year of data are available is recommended.…”

Comparing Sentinel-2A and Landsat 7 and 8 Using Surface Reflectance over Australia

“…In any case, it is beyond the scope of this analysis to attempt to assess or improve on the registration. The ESA are planning to re-process all of their Sentinel-2 imagery with an improved ground reference image, but this has not yet been put in place for processing of Australian imagery [24]. Table 4 gives the coefficients fitted for Equation (1), for each band and sensor combination.…”

Improved Co-Registration of Sentinel-2 and Landsat-8 Imagery for Earth Surface Motion Measurements

“…For Sentinel-2, this concerns in particular early acquisitions processed before yaw bias correction is applied in the processing baseline 2.04 [8]. For Landsat-8, a similar yaw bias correction is applied since October 2013 [34] including reprocessing of earlier scenes.…”

“…The algorithm has several free parameters including the window size ω, the correlation threshold C min , the regularization parameter reg and the sub-pixel precisions spp, which in accordance to previous study [17] were set to ω = 9, C min = 0.33, reg = 0.2 and spp = 0.1. Considering the estimated co-registration error of 38 m, the search range r search was set to 4 pixels (Sentinel-2, 10 m) or 40 m. For the Sentinel-2/Sentinel-2 case, the red band is used for matching since it is also used as the reference for band-to-band co-registration [8]. For the Landsat-8/Sentinel-2 case, a synthetic panchromatic band is generated from the three Sentinel-2 bands in the visible spectra and the Landsat-8 panchromatic band is reprojected to the Sentinel-2 tile layout at 10 m resolution before matching.…”