Structure, morphology and water flux of a subglacial drainage system, Midtdalsbreen, Norway

被引:20
作者
Willis, Ian C. [1 ]
Fitzsimmons, Chris D. [1 ]
Melvold, Kjetil [2 ]
Andreassen, Liss M. [2 ,3 ]
Giesen, Rianne H. [4 ]
机构
[1] Univ Cambridge, Dept Geog, Scott Polar Res Inst, Cambridge CB2 3EN, England
[2] Norwegian Water Resources & Energy Directorate NV, N-0301 Oslo, Norway
[3] Univ Oslo, Dept Geog, N-0316 Oslo, Norway
[4] Inst Marine & Atmospher Res Utrecht IMAU, NL-3508 TA Utrecht, Netherlands
基金
英国自然环境研究理事会;
关键词
glacier hydrology; dye tracing; digital elevation model; degree-day melt model; water discharge; HAUT GLACIER DAROLLA; DIGITAL ELEVATION MODELS; POLYTHERMAL GLACIER; TRACER EXPERIMENTS; OUTBURST EVENTS; SURGE MECHANISM; BED TOPOGRAPHY; ABLATION AREA; LOWER PART; FLOW;
D O I
10.1002/hyp.8431
中图分类号
TV21 [水资源调查与水利规划];
学科分类号
081501 ;
摘要
Digital elevation models of the surface and bed of Midtdalsbreen, Norway are used to calculate subglacial hydraulic potential and infer drainage system structure for a series of subglacial water pressure assumptions ranging from atmospheric to ice overburden. A distributed degree-day model is used to calculate the spatial distribution of melt on the glacier surface throughout a typical summer, which is accumulated along the various drainage system structures to calculate water fluxes beneath the glacier and exiting the portals for the different water pressure assumptions. In addition, 78 dye-tracing tests were performed from 33 injection sites and numerous measurements of water discharge were made on the main proglacial streams over several summer melt seasons. Comparison of the calculated drainage system structures and water fluxes with dye tracing results and measured proglacial stream discharges suggests that the temporally and spatially averaged steady-state water pressures beneath the glacier are?similar to 70% of ice overburden. Analysis of the dye return curves, together with the calculated subglacial water fluxes shows that the main drainage network on the eastern half of the glacier consists of a hydraulically efficient system of broad, low channels (average width/height ratio?similar to?75). The smaller drainage network on the west consists of a hydraulically inefficient distributed system, dominated by channels that are exceptionally broad and very low (average width/height ratio?similar to?350). The even smaller central drainage network also consists of a hydraulically inefficient distributed system, dominated by channels that are very broad and exceptionally low (average width/height ratio?similar to?450). The channels beneath the western and central glacier must be so broad and low that they can essentially be thought of as a linked cavity system. Copyright (c) 2011 John Wiley & Sons, Ltd.
引用
收藏
页码:3810 / 3829
页数:20
相关论文
共 78 条
[1]  
Andersen J.L., 1971, Norwegian Journal of Geography, V25, P1, DOI DOI 10.1080/00291957108551908
[2]  
Andersen LM, 1996, THESIS U OSLO NORWAY
[3]   Glacier mass-balance and length variation in Norway [J].
Andreassen, Liss M. ;
Elvehoy, Hallgeir ;
Kjollmoen, Bjarne ;
Engeset, Rune V. ;
Haakensen, Nils .
ANNALS OF GLACIOLOGY, VOL 42, 2005, 2005, 42 :317-325
[4]  
[Anonymous], Z GLETSCHERKUNDE GLA
[5]  
Arcement Jr G., 1989, 2339 US GEOL SURV, P1
[6]   Seasonal evolution of subglacial drainage and acceleration in a Greenland outlet glacier [J].
Bartholomew, Ian ;
Nienow, Peter ;
Mair, Douglas ;
Hubbard, Alun ;
King, Matt A. ;
Sole, Andrew .
NATURE GEOSCIENCE, 2010, 3 (06) :408-411
[7]   Subglacial drainage processes at a High Arctic polythermal valley glacier [J].
Bingham, RG ;
Nienow, PW ;
Sharp, MJ ;
Boon, S .
JOURNAL OF GLACIOLOGY, 2005, 51 (172) :15-24
[8]   Intra-annual and intra-seasonal flow dynamics of a High Arctic polythermal valley glacier [J].
Bingham, RG ;
Nienow, PW ;
Sharp, MJ .
ANNALS OF GLACIOLOGY, VOL 37, 2003, 37 :181-188
[9]   Hydrology and dynamics of a polythermal (mostly cold) High Arctic glacier [J].
Bingham, Robert G. ;
Nienow, Peter W. ;
Sharp, Martin J. ;
Copland, Luke .
EARTH SURFACE PROCESSES AND LANDFORMS, 2006, 31 (12) :1463-1479
[10]   Hydrological characteristics of the drainage system beneath a surging glacier [J].
Björnsson, H .
NATURE, 1998, 395 (6704) :771-774