Effects of bedrock lithology and subglacial till on the motion of Ruth Glacier, Alaska, deduced from five pulses from 1973 to 2012

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Publication Type pre-print
School or College College of Social & Behavioral Science
Department Geography
Creator Forster, Richard R.
Other Author Turrin, James B.; Sauber, Jeanne M.; Hall, Dorothy K.; Bruhn, Ronald L.
Title Effects of bedrock lithology and subglacial till on the motion of Ruth Glacier, Alaska, deduced from five pulses from 1973 to 2012
Date 2014-01-01
Description A pulse is a type of unstable glacier flow intermediate between normal flow and surging. Using Landsat MSS, TM and ETM+ imagery and feature-tracking software, a time series of mostly annual velocity maps from 1973 to 2012 was produced that reveals five pulses of Ruth Glacier, Alaska. Peaks in ice velocity were found in 1981, 1989, 1997, 2003 and 2010, approximately every 7 years. During these peak years the ice velocity increased 300%, from approximately 40ma-1 to 160ma-1. Based on the spatio-temporal behavior of Ruth Glacier during the pulse cycles, we suggest the pulses are due to enhanced basal motion via deformation of a subglacial till. The cyclical nature of the pulses is interpreted to be due to a thin till, with low permeability, that causes incomplete drainage of the till between the pulses, followed by eventual recharge and dilation of the till. These findings suggest care is needed when attempting to correlate changes in regional climate with decadal-scale changes in velocity, because in some instances basal conditions may have a greater influence on ice dynamics than climate.
Type Text
Publisher International Glaciological Society
Volume 60
Issue 222
First Page 771
Last Page 781
Language eng
Bibliographic Citation Turrin, J. B., Forster, R. R., Sauber, J. M., Hall, D. K., & Bruhn, R. L. (2014). Effects of bedrock lithology and subglacial till on the motion of Ruth Glacier, Alaska, deduced from five pulses from 1973 to 2012. Journal of Glaciology, 60(222), 771-81.
Rights Management (c)International Glaciological Society http://www.igsoc.org/
Format Medium application/pdf
Format Extent 1,326,442 bytes.
Identifier uspace,19076
ARK ark:/87278/s6gf43nm
Setname ir_uspace
Date Created 2015-06-26
Date Modified 2021-05-06
ID 713110
Reference URL https://collections.lib.utah.edu/ark:/87278/s6gf43nm
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