A Wide-Angle Hyperspectral Top-of-Atmosphere Reflectance Model for the Libyan Desert

• Published in: Remote sensing (Basel, Switzerland) Vol. 16; no. 8; p. 1406
• Main Authors: Guo, Fuxiang, Zheng, Xiaobing, Zhang, Yanna, Wei, Wei, Zhang, Zejie, Zhang, Quan, Li, Xin
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-04-2024
• Subjects: Accuracy; Aircraft; Atmosphere; Calibration; Deserts; Earth resources technology satellites; Earth surface; hyperspectral; Imaging radiometers; Infrared imaging; Infrared radiometers; Landsat; Landsat satellites; Libyan Desert; Mathematical models; Meteorological satellites; Model accuracy; Parameters; PICS; radiometric calibration; Radiometry; Reflectance; Remote sensing; Remote sensors; Root-mean-square errors; Satellite observation; Satellites; Sensors; Short wave radiation; Spectral bands; Spectral reflectance; Spectroradiometers; TOA reflectance; Viewing; Libya
• ISSN: 2072-4292; 2072-4292
• DOI: 10.3390/rs16081406

Reference targets with stability, uniformity, and known reflectance on the Earth’s surface, such as deserts, can be used for the absolute radiometric calibration of satellite sensors. A wide-angle hyperspectral reflectance model at the top of atmosphere (TOA) over such a reference target will expand the applicability of on-orbit calibration to different spectral bands and angles. To achieve the long-term, continuous, and high-precision absolute radiometric calibration of remote sensors, a wide-angle hyperspectral TOA reflectance model of the Libyan Desert was constructed based on spectral reflectance data, satellite overpass parameters, and atmospheric parameters from the Terra/Aqua and Earth Observation-1 (EO-1) satellites between 2003 and 2012. By means of angle fitting, viewing angle grouping, and spectral extension, the model is applicable for absolute radiometric calibration of the visible to short-wave infrared (SWIR) bands for sensors within viewing zenith angles of 65 degrees. To validate the accuracy and precision of the model, a total of 3120 long-term validations of model accuracy and 949 cross-validations with the Landsat 8 Operational Land Imager (OLI) and Suomi National Polar-Orbiting Partnership (NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) satellite sensors between 2013 and 2020 were conducted. The results show that the TOA reflectance calculated by the model had a standard deviation (SD) of relative differences below 1.9% and a root-mean-square error (RMSE) below 0.8% when compared with observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Landsat 8 OLI. The SD of the relative differences and the RMSE were within 2.7% when predicting VIIRS data.