The structural, geometric and volumetric changes of a polythermal Arctic glacier during a surge cycleComfortlessbreen, Svalbard

Type Article
Original languageEnglish
Pages (from-to)162-177
Number of pages15
JournalEarth Surface Processes and Landforms
Volume41
Issue number2
Early online date12 Oct 2015
DOI
Publication statusPublished - Feb 2016
Links
Handle.net
Show download statistics
View graph of relations
Citation formats

Abstract

Various parameters of the most recent surge of the polythermal glacier Comfortlessbreen in northwest Svalbard, have been assessed through a combination of remote sensing and ground observations. Analysis of a digital elevation model time-series shows a marked change in the geometry of the glacier from quiescence (1990 and earlier) into the late surge phase (2009). The transfer of 0.74 km3 of ice caused up to 80 m of surface drawdown in the reservoir area, above the equilibrium line, whilst ice built up in a spatially concentrated manner in the receiving zone, below the equilibrium line. A ramp of ice, c. 100 m above quiescent level, developed in the lower reaches of the glacier late in the surge. Also in the lower reaches of the glacier, structures attributable to the passage of a kinematic wave are identified and the migration of a surge front on the glacier is thus inferred. In a conceptual model, we consider that a bend in the valley, in which the glacier resides, and convergence with tributary glaciers, to be significant factors in the style of surge evolution. Their flow-restrictive interference results in slow initial mass-transfer and the growth of a surge front within 3–4 km of the terminus. Copyright © 2015 John Wiley & Sons, Ltd.

Keywords

  • surge, glacier structure, geometric changes, Comfortlessbreen, Svalbard