Intercomparison of Earth-Observing Sensors Using the Radiometric Calibration Test Site (RadCaTS)

The Radiometric Calibration Test Site (RadCaTS) is a suite of ground-based instruments operating at Railroad Valley, Nevada, USA. Surface reflectance and atmospheric data are collected throughout the day so that top-of-atmosphere (TOA) spectral radiance and reflectance can be provided to satellite sensor operators. Its development arose from the need to accumulate data in the absence of ground personnel, which has become even more essential with the recent launches of very large satellite constellations. RadCaTS has been used to monitor and validate the radiometric calibration of sensors ranging from multispectral to hyperspectral, with spatial resolutions ranging from ~1-1000 m. The work presented here provides a description of the system as well as examples of current RadCaTS results for the Landsat-8 Operational Land Imager (OLI) and the Sentinel-2A and -2B Multispectral Instrument (MSI).