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In preparation for new satellite sensors, such as VEGE-ciated with vegetation, and as an input to ecosystem pro-TATION on SPOT-4 and the MODerate Resolution Im-ductivity models (Sellers et al., 1986; Bonan, 1993; Liu aging Spectrometer (MODIS), we investigate the poten-et al., 1997). The need for LAI information over large tial of the shortwave infrared(More)
Leaf area index (LAI) is one of the surface parameters that has importance in climate, weather, and ecological studies, and has been routinely estimated from remote sensing measurements. Canada-wide LAI maps are now being produced using cloud-free Advanced Very High-Resolution Radiometer (AVHRR) imagery every 10 days at 1-km resolution. The archive of these(More)
Optical instruments currently available for measuring the leaf-area index (LAI) of a plant canopy all utilize only the canopy gap-fraction information. These instruments include the Li-Cor LAI-2000 Plant Canopy Analyzer, Decagon, and Demon. The advantages of utilizing both the canopy gap-fraction and gap-size information are shown. For the purpose of(More)
[1] Our current understanding of terrestrial carbon processes is represented in various models used to integrate and scale measurements of CO 2 exchange from remote sensing and other spatiotemporal data. Yet assessments are rarely conducted to determine how well models simulate carbon processes across vegetation types and environmental conditions. Using(More)
Global mapping of the vegetation clumping index is attempted for the first time using multi-angular POLDER 1 data based on a methodology that has been demonstrated to be applicable to Canada's landmass. The clumping index quantified the level of foliage grouping within distinct canopy structures, such as tree crowns, shrubs, and row crops, relative to a(More)
The retrieval of canopy architectural parameters using off-the-shelf digital cameras with fish-eye lens is investigated. The technique used takes advantage of the sensor's linear response to light of these cameras to improve the estimation of gap fraction using: (1) the digital numbers of mixed sky-canopy pixels to estimate the within-pixel gap fraction;(More)
— Open boreal forests present a challenge in understanding remote sensing signals acquired with various solar and view geometries. Much research is needed to improve our ability to model the bidirectional reflectance distribution (BRD) for retrieving the surface information using measurements at a few angles. The geometric-optical bidirectional reflectance(More)
—Satellite-derived vegetation indices and their resulting surface parameters, such as the leaf area index (LAI), are inevitably affected by the atmosphere. Errors in the atmospheric corrections can often be easily identified in a seasonal trajectory of a surface parameter because the atmospheric effect generally causes erratic reductions in vegetation(More)