Surface reflectance measurements in the UV from an airborne platform. Part 1.
The reflectance of naturally occurring surfaces is measured from a twin engine Cessna 402B aircraft both spectrally (0.29-0.40 microm) with a compact double monochromator and broadband (0.29-1.2 microm) with a UV enhanced photodiode. The measurement system, which is computer controlled and electrically isolated from the aircraft, consists of upward and downward looking hemispheric diffusers, filters, a rotating 90 degrees mirror, a focusing lens, and a double monochromator/PMT or the UV photodiode. Measurements are taken at several altitudes enabling the empirical determination of backscatter and attenuation effects on the reflectance. The results are presented for pine forest canopy, green farmland, open ocean, and brown farmland as a function of wavelength and altitude.