Reflectance characteristics of arctic tundra vegetation from airborne radiometry

Abstract

The objectives of this study were to (1) develop and test an airborne radiometer system for sampling spectral radiances over arctic tundra landscapes, (2) quantify variations in the Normalized Difference Vegetation Index (NDVI) as a function of tundra vegetation type and seasonal date, and (3) quantify variations of spectral radiance and NDVI in response to possible anthropogenic disturbance. Spectral radiometer data analyzed in this study were acquired over the northern foothills of the Brooks Range in Alaska. The radiometer was well suited to data acquisition in the arctic environment. Mean NDVI values for four major vegetation types during each of three seasonal dates were significantly different from each other. Seasonal trajectories of the NDVI for each vegetation type corresponded to general phenological characteristics of the vegetation. The spectral radiance in red and near infrared wavebands appears to respond to disturbance caused by dust deposition from the Dalton Highway.