Glacier Mass Balance Changes and Meltwater Discharge (selected papers from sessions at the IAHS Assembly in Foz do Iguaçu

Abstract Detection of crevasses is critical for safe travelling on glaciers. Here we present the use of a Ground Penetrating Radar (GPR) for crevasse detection. Experiments were made in temperate ice on Glaciar Mocho, Volcán MochoChoshuenco, southern Chile (39°25′S) and in cold ice in East Antarctic...

Full description

Bibliographic Details
Main Authors: Rodrigo Zamora, Gino Casassa, Andres Rivera, Fernando Ordenes, Guillermo Neira, Luis Araya, Ronald Mella, Claudio Bunster
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1085.4041
http://www.glaciologia.cl/web/glaciologia_es/glaciologiacms/upload/zamora2007.pdf
Description
Summary:Abstract Detection of crevasses is critical for safe travelling on glaciers. Here we present the use of a Ground Penetrating Radar (GPR) for crevasse detection. Experiments were made in temperate ice on Glaciar Mocho, Volcán MochoChoshuenco, southern Chile (39°25′S) and in cold ice in East Antarctica (87°30′S). In southern Chile the radar was hand-carried 1.2 m in front of the operator who was walking over the glacier at a speed of ~0.5 m s -1 , while in Antarctica it was mounted on a 7 m-long rod in front of a tractor convoy travelling at a speed of ~2 m s -1 . In both geographical sites profiles were made perpendicularly to crevasses ranging in width from 0.1 m to 1.0 m. Buried crevasses clearly show as apexes of diffraction hyperbolae, which could be detected down to a depth of 15 m. Show as discontinuities in the firn stratigraphy which have a width equal to the crevasse width, and associated diffraction hyperbolae to each side of the crevasse. The GPR proved to be a valuable tool for detecting crevasses, allowing for a reaction time of ~9 s (equivalent to ~4.5 m on the ground) in the case of the hand-carried system and ~5 s (or ~10 m on the ground) for the tractor system.