Temporal Variation in Surface Bidirectional Reflectance of the Railroad Valley Vicarious Calibration Test Site in Nevada

Byford, Nicole; Coburn, Craig A.

doi:10.1080/07038992.2022.2114439

Cited by 3 publications

(1 citation statement)

References 31 publications

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“…In other research, a hemispherical goniometer has mainly been used to estimate the BRDF. Among the goniometers mainly used in field work for BRDF estimation are the Portable Apparatus for Rapid Acquisition of Bidirectional Observation of the Land and Atmosphere (PARABOLA) [ 8 , 9 ], University of Lethbridge Goniometer System (ULGS-2) [ 10 , 11 ], Gonio RAdiometric Spectrometer System (GRASS) [ 12 , 13 , 14 , 15 ], and Goniometer for Outdoor Portable Hyperspectral Earth Reflectance (GOPHER) [ 16 , 17 , 18 ]. These goniometers are not portable because of their large size, and some can only acquire the surface data for a quarter of the hemisphere.…”

Section: Introductionmentioning

confidence: 99%

Calibration of BRDF Based on the Field Goniometer System Using a UAV Multispectral Camera

Kim

Jin

Lee

et al. 2022

Sensors

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The bidirectional reflectance distribution function (BRDF) is important for estimating the physical properties of a surface in remote sensing. In the laboratory, the BRDF can be estimated quickly and accurately using a goniometer, but it is very difficult to operate in the field. The purpose of this study was to evaluate whether estimating the BRDF with reasonable accuracy using an unmanned aerial vehicle (UAV) with a multispectral camera is possible in the field. Hemispherical reflectance was created from images taken using an UAV multispectral camera. The ground targets were four calibrated reference tarps (CRTs) of different reflectance, and the UAV was operated five times. Down-welling irradiance for reflectance calculation was measured in two ways: a sunlight sensor was mounted on a UAV, and a spectroradiometer with a remote cosine receptor (RCR) was installed on the ground. The BRDF was assessed through the anisotropy factor (ANIF) of the CRT reflectance derived from the collected data. As a result, the irradiance data for the reflectance calculation were more effective from the spectroradiometer with RCR on the ground than from the sunlight sensor mounted on an UAV. Furthermore, the high reflectance CRTs, ANIF, and BRDF had similar results. Therefore, when analyzing the BRDF, the effectiveness can be guaranteed when the reflectance of the target is over 21~46%, because a low reflectance tendency differs due to the adjacency effect. In addition, weather affects irradiance, so it is more effective to conduct fieldwork in clear weather.

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Section: Introductionmentioning

confidence: 99%

Calibration of BRDF Based on the Field Goniometer System Using a UAV Multispectral Camera

Kim

Jin

Lee

et al. 2022

Sensors

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Validation of the TOA Products of the Baotou Sandy Site With Landsat8/OLI Considering BRDF Correction

Han

Tao

Xie

et al. 2023

IEEE Trans. Geosci. Remote Sensing

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Combining RadCalNet Sites for Radiometric Cross Calibration of Landsat 9 and Landsat 8 Operational Land Imagers (OLIs)

Voskanian,

Thome,

Wenny

et al. 2023

Remote Sensing

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Combining images from multiple Earth Observing (EO) satellites increases the temporal resolution of the data, overcoming the limitations imposed by low revisit time and cloud coverage. However, this requires an intercalibration process to ensure that there is no radiometric difference in top-of-atmosphere (TOA) observations or to quantify any offset in the respective instruments. In addition, combining vicarious calibration processes to the intercalibration of instruments can provide a useful mechanism to validate and compare data from multiple sensors. The Radiometric Calibration Network (RadCalNet) provides automated surface and top-of-atmosphere reflectance data from multiple participating ground sites that can be used for instrument vicarious calibration. We present a comparative analysis of the Landsat 8 and Landsat 9 Operational Land Imagers (OLI) sensors and validate the data by comparing them to measurements from RadCalNet sites as a quantitative intercalibration approach. RadCalNet serves as a common reference for instrument radiometric calibration, providing SI-traceable TOA reflectance with its associated absolute uncertainties. This paper discusses the method of combining data from multiple sites and calculating the weighted average by comparing the TOA reflectance of the instruments and their associated uncertainties. The presented process provides a SI-traceable intercalibration methodology and quantifies the offset and uncertainty in the Landsat 8 and 9 OLI instruments, demonstrating that the two instruments are in good agreement with each other and the data can be reliably cross-correlated and used by the scientific community.

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Temporal Variation in Surface Bidirectional Reflectance of the Railroad Valley Vicarious Calibration Test Site in Nevada

Cited by 3 publications

References 31 publications

Calibration of BRDF Based on the Field Goniometer System Using a UAV Multispectral Camera

Calibration of BRDF Based on the Field Goniometer System Using a UAV Multispectral Camera

Validation of the TOA Products of the Baotou Sandy Site With Landsat8/OLI Considering BRDF Correction

Combining RadCalNet Sites for Radiometric Cross Calibration of Landsat 9 and Landsat 8 Operational Land Imagers (OLIs)

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