Measurement of snowpack properties using active FM-CW microwave systems
Date
1982
Authors
Farr, John Merritt, author
Boyne, Harold S., advisor
Smith, Freeman M. (Freeman Minson), 1939-, committee member
Smith, James A., committee member
Journal Title
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Abstract
This paper reports on the use of an FM-CW active microwave system, in a research mode, to remotely sense water equivalence and liquid water content of snowpacks. A three-component "electrical path length" dielectric mixture model is described which accounts for the microwave system response as a function of operating frequency, snow density and depth (water equivalence), and liquid water content. This physically based model is compared to currently accepted, semi-empirical mixture models and the limited data that exists. The "electrical path length" model compares favorably and has a distinctly simpler form than other models, making it workable for the specific problem addressed. It is concluded that by collecting data in two frequency ranges (just below the relaxation frequency of water), the depth of ice, the depth of liquid water, and thus the water equivalence of dry or wet snowpacks could be determined. Liquid water content determinations, made on a real-time basis, could then serve as invaluable melt-rate indexes for remote sites. Recommendations are given for the design configuration of an operational system, which could be incorporated into hydrometeorological data acquisition platforms such as SNOTEL.
Description
Rights Access
Subject
Snow -- Measurement
Remote sensing
Microwave measurements