Evidence for temporally varying "sticky spots" at the base of Trapridge Glacier, Yukon Territory, Canada
Abstract:During the 1992 summer field season we installed arrays of "plough- meters" and water-pressure transducers beneath Trapridge Glacier, Yukon Territory, Canada, to study hydromechanical coupling at the icc-bed interface. Diurnal signals rccorded with two of thcse ploughmctcrs appcar to correlatc with fluctuations in sub- glacial water pressurc. These diurnal variations can be explained by changes in basal resistance to sliding as mechanical conditions at the bed vary temporally in response to changes in the subglacial hydrological system. We propose that a lubricating water film, associated with high water pressures, promotes glacier sliding, whereas low pressures cause increascd basal drag resulting in "sticky" arcas. Using a thcorctical model, we analyze the sliding motion of glacier ice over a flat surface having variable basal drag and show that a consistent explanation can be developed. Results from our model calculations provide strong support for the existence of time-varying sticky spots which are associated with fluctuations in subglacial water pressure.
Document Type: Research Article
Publication date: June 1, 1999
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.
- Editorial Board
- Information for Authors
- ingentaconnect is not responsible for the content or availability of external websites