000			02780nab a22003257a 4500
001			G90178
003			MX-TxCIM
005			20190314211106.0
008			121211b |||p||p||||||| |z||| |
040			_aMX-TxCIM
090			_aREP-12973
100	1		_aPeddle, D.R.
245	0	0	_aReflectance processing of remote sensing spectroradiometer data
260			_c2001
340			_aComputer File|Printed
520			_aSpectral reflectance is the ratio of incident-to-reflected radiant flux measured from an object or area over specified wavelengths. Unlike radiance and irradiance values, reflectance is an inherent property of an object and is independent of time, location, illumination intensity, atmospheric conditions and weather. Although reflectance is a key unit of measure in remote sensing, it is not measured directly and instead must be derived. Accordingly, the conversion of field and laboratory measurements of spectral radiance into reflectance values is a frequent requirement with ground data in support of airborne and satellite remote sensing applications in the environmental and earth sciences. In this paper, laboratory and computer methods for processing field spectroradiometer measurements of spectral radiance into calibrated absolute reflectance values are described. Target radiance measures are obtained under direct and diffuse illumination using a portable field spectroradiometer, with irradiance spectra captured by near simultaneous acquisition of reflected radiation from a reference panel. The approach for converting raw target and panel radiance spectra to calibrated reflectance involves five major processing stages: (i) panel calibration, (ii) solar zenith angle computations, (iii) spectral and angular interpolation, (iv) computation of reflectance, and (v) automated batch mode execution of stages (ii)–(iv) for processing large data volumes. Equipment, methods, and computer programs for achieving these stages are described. Example forestry ground spectra acquired in the Boreal Ecosystem Atmosphere Study (BOREAS) are presented to illustrate raw field measurements and final reflectance products. These methods would also be useful in other applications such as agriculture, water resources, oceanic studies, rangeland management, and geological exploration and mineral identification.
546			_aEnglish
650	1	0	_aBOREAS
650	1	0	_aCalibration
650	1	0	_aRadiance
650	1	0	_aReflectance
650	1	0	_91986 _aRemote sensing _gAGROVOC
650	1	0	_aSpectroradiometer
700	1		_aLeDrew, E.F., _ecoaut.
700	1		_aMiller, J.R., _ecoaut.
700	1		_aSoffer, R.J., _ecoaut.
700	1		_aWhite, H.P., _ecoaut.
773	0		_tComputers and Geosciences _n634955 _gv. 27, no. 2, p. 203-213
942			_cJA _2ddc
999			_c26896 _d26896