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Title: On the detection of crevasses in glacial ice with synthetic-aperture radar.

Abstract

The intent of this study is to provide an analysis of the scattering from a crevasse in Antarctic ice, utilizing a physics-based model for the scattering process. Of primary interest is a crevasse covered with a snow bridge, which makes the crevasse undetectable in visible-light images. It is demonstrated that a crevasse covered with a snow bridge can be visible in synthetic-aperture-radar (SAR) images. The model of the crevasse and snow bridge incorporates a complex dielectric permittivity model for dry snow and ice that takes into account the density profile of the glacier. The surface structure is based on a fractal model that can produce sastrugi-like features found on the surface of Antarctic glaciers. Simulated phase histories, computed with the Shooting and Bouncing Ray (SBR) method, are processed into SAR images. The viability of the SBR method for predicting scattering from a crevasse covered with a snow bridge is demonstrated. Some suggestions for improving the model are given.

Authors:
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
989382
Report Number(s):
SAND2010-0363
TRN: US201019%%608
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; DETECTION; DIELECTRIC MATERIALS; FRACTALS; GLACIERS; PERMITTIVITY; RADAR; SCATTERING; SNOW; VIABILITY; Glaciers-Forecasting.; Synthetic aperture radar-Image quality.

Citation Formats

Brock, Billy C. On the detection of crevasses in glacial ice with synthetic-aperture radar.. United States: N. p., 2010. Web. doi:10.2172/989382.
Brock, Billy C. On the detection of crevasses in glacial ice with synthetic-aperture radar.. United States. doi:10.2172/989382.
Brock, Billy C. Mon . "On the detection of crevasses in glacial ice with synthetic-aperture radar.". United States. doi:10.2172/989382. https://www.osti.gov/servlets/purl/989382.
@article{osti_989382,
title = {On the detection of crevasses in glacial ice with synthetic-aperture radar.},
author = {Brock, Billy C.},
abstractNote = {The intent of this study is to provide an analysis of the scattering from a crevasse in Antarctic ice, utilizing a physics-based model for the scattering process. Of primary interest is a crevasse covered with a snow bridge, which makes the crevasse undetectable in visible-light images. It is demonstrated that a crevasse covered with a snow bridge can be visible in synthetic-aperture-radar (SAR) images. The model of the crevasse and snow bridge incorporates a complex dielectric permittivity model for dry snow and ice that takes into account the density profile of the glacier. The surface structure is based on a fractal model that can produce sastrugi-like features found on the surface of Antarctic glaciers. Simulated phase histories, computed with the Shooting and Bouncing Ray (SBR) method, are processed into SAR images. The viability of the SBR method for predicting scattering from a crevasse covered with a snow bridge is demonstrated. Some suggestions for improving the model are given.},
doi = {10.2172/989382},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Feb 01 00:00:00 EST 2010},
month = {Mon Feb 01 00:00:00 EST 2010}
}

Technical Report:

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