Microwave Determination of Snowpack Liquid Water Content.

• Main Author: Boyne,H S
• Other Authors: COLORADO STATE UNIV FORT COLLINS DEPT OF EARTH RESOURCES
• Format: Text
• Language: English
• Published: 1985
• Subjects: Snow; Ice and Permafrost; Test Facilities; Equipment and Methods; *SNOW; MEASUREMENT; VOLUME; PERMEABILITY; LABORATORY TESTS; LAYERS; LIQUIDS; WATER; CONTINUOUS WAVES; FIELD TESTS; DIELECTRICS; PATHS; TEST METHODS; ACCURACY; MICROWAVES; MICROWAVE EQUIPMENT; ELECTRICAL PROPERTIES; MOISTURE CONTENT; DEPTH; STRATIGRAPHY; DIELECTRIC PROPERTIES; LENGTH; HETEROGENEITY; DILUTION; DETERMINATION; MICROWAVE FREQUENCY; DISPERSIONS; Snowpack water content; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA161798; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA161798

The measurement of liquid water in snowpack based on the electrical path length difference in snowpack depth in the region of high dielectric dispersion of water is described. The measurement system consists of a previously described LFM/CW microwave system (Ellerbruck and Boyne, 1980) operating at two frequency bands 2-5 GHz and 5-8 GHz. The system is tested, evaluated and intercompared with a dilution measurement technique (Davis, et. al. 1985) in both a laboratory and field environment. It is found that the two methods of intercomparison are equivalent provided the snowpack is homogeneous and free of stratigraphy. The accuracy of the intercomparison is + or - 2.5% at the 95% level of confidence. The intercomparison of the methods is not equivalent when compared in an inhomegeneous stratified snowpack. The microwave system consistently registers a higher volumetric liquid water content than the dilution method. This discrepancy is believed due to differences in the snowpack volumes sampled. In particular, it is believed that ponded water above impermeable layers regions in the snowpack is responsible for the discrepancy. These regions could not be cored successfully for measurement by the dilution method. (Author)