Skip to main content

Airborne-radar stratigraphy and electrical structure of temperate firn: Bagley Ice Field, Alaska, U.S.A.

The full text article is not available for purchase.

The publisher only permits individual articles to be downloaded by subscribers.


Helicopter-borne 135 MHz short-pulse radar profiles of the Bagley Ice Field, southern Alaska, U.S.A., have been analyzed to determine the nature of radio-wave propagation through crevassed, stratified, wet and draining firn. Diffractions characterize the firn horizons along the trunk, and reflections characterize those of overlying snowfields. Dynamic stacking was used to form and determine firn depths, and unstacked diffraction analysis to determine firn-layer properties. Refractive indices range from 4.1 to 4.5 for the near-surface, from 1.7 to 2.1 at about 13-17 m depth along the main trunk, and to 2.6 to 58 m depth within a snowfield. Average trunk values correspond with volumetric water contents of about 0.09, which agree with values measured for other glaciers. The analysis of the airborne-recorded diffractions is confirmed by deriving the approximate refractive index of water from a supraglacial lake-bottom diffraction. The lack of snowfield diffractions suggests that crevassing and not firn structure caused the trunk diffractions. The reasonable values of the indices imply that the diffractions originated from single points or edges orthogonal to the profile transect, and they predict low interlayer transmission losses. The snowfield penetration suggests that several hundred meters might be penetrated in uncrevassed accumulation zones with improved system design.

Document Type: Research Article


Publication date: 2002-03-01

More about this publication?
  • The Journal of Glaciology is published six times per year. It accepts submissions from any discipline related to the study of snow and ice. All articles are peer reviewed. The Journal is included in the ISI Science Citation Index.

    Beginning in 2016, content will be available at
  • Editorial Board
  • Information for Authors
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more