Ice-Dammed Lake Drainage Evolution at Russell Glacier, West Greenland

Autor: Jonathan L. Carrivick, Fiona S. Tweed, Felix Ng, Duncan J. Quincey, Joseph Mallalieu, Thomas Ingeman-Nielsen, Andreas B. Mikkelsen, Steven J. Palmer, Jacob C. Yde, Rachel Homer, Andrew J. Russell, Alun Hubbard
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Frontiers in Earth Science, Vol 5 (2017)
Druh dokumentu: article
ISSN: 2296-6463
DOI: 10.3389/feart.2017.00100
Popis: KEY POINTS/HIGHLIGHTSTwo rapid ice-dammed lake drainage events gauged and ice dam geometry measured.A melt enlargement model is developed to examine the evolution of drainage mechanism(s).Lake temperature dominated conduit melt enlargement and we hypothesize a flotation trigger.Glaciological and hydraulic factors that control the timing and mechanisms of glacier lake outburst floods (GLOFs) remain poorly understood. This study used measurements of lake level at 15 min intervals and known lake bathymetry to calculate lake outflow during two GLOF events from the northern margin of Russell Glacier, west Greenland. We used measured ice surface elevation, interpolated subglacial topography and likely conduit geometry to inform a melt enlargement model of the outburst evolution. The model was tuned to best-fit the hydrograph rising limb and timing of peak discharge in both events; it achieved Mean Absolute Errors of
Databáze: Directory of Open Access Journals