COMPARATIVE-ANALYSIS OF DATA ACQUIRED BY 3 NARROW-BAND AIRBORNE SPECTRORADIOMETERS OVER SUBBOREAL VEGETATION

Calibrated radiance data were acquired with three airborne sensor syst ems on 8 September 1990 over a northern forest as part of the Forest E cosystem Dynamics Multisensor Aircraft Campaign. The spectral data wer e acquired nearly simultaneously under extremely clear sky conditions with NASA's AVIRIS and ASAS imaging spectroradiometers, and an SE-590 spectroradiometer mounted on a NASA UH-1B helicopter. After atmospheri c corrections were applied to these data, intercomparisons Of nadir re flectance factor measurements from each of these sensors were made for four important vegetation communities including a bog and individual forest stands dominated by spruce (Picea sp.), eastern hemlock (Tsuga canadensis), and mixed northern hardwoods (dominated by Acer sp., Popu lus sp., and Betula sp.), respectively. The reflectance factor spectra from the different instruments were comparable for each of these cove r types, suggesting the possible interchangeable use of the three data sets over comparable wavelength regions. These comparisons also serve to graphically illustrate the importance of applying atmospheric corre ctions to such data, even if acquired under extremely clear sky condit ions. This remote sensing data set appears suitable for assessing the applicability of multistage, multisensor data in large-scale ecologica l research.