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spaceborne applications of p band imaging radars for measuring forest biomassIn three sites of boreal and temperate forests, P band HH, HV, and VV polarization data combined estimate total aboveground dry woody biomass within 12 to 27% of the values derived from allometric equations, depending on forest complexity. Biomass estimates derived from HV-polarization data only are 2 to 14% less accurate. When the radar operates at circular polarization, the errors exceed 100% over flooded forests, wet or damaged trees and sparse open tall forests because double-bounce reflections of the radar signals yield radar signatures similar to that of tall and massive forests. Circular polarizations, which minimize the effect of Faraday rotation in spaceborne applications, are therefore of limited use for measuring forest biomass. In the tropical rain forest of Manu, in Peru, where forest biomass ranges from 4 kg/sq m in young forest succession up to 50 kg/sq m in old, undisturbed floodplain stands, the P band horizontal and vertical polarization data combined separate biomass classes in good agreement with forest inventory estimates. The worldwide need for large scale, updated, biomass estimates, achieved with a uniformly applied method, justifies a more in-depth exploration of multi-polarization long wavelength imaging radar applications for tropical forests inventories.
Document ID
19990111506
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Rignot, Eric J.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
Zimmermann, Reiner
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
vanZyl, Jakob J.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA United States)
Date Acquired
August 19, 2013
Publication Date
September 1, 1995
Publication Information
Publication: IEEE Transactions on Geoscience and Remote Sensing
Volume: 33
Issue: 5
ISSN: 0196-2892
Subject Category
Communications and Radar
Distribution Limits
Public
Copyright
Other