Water flow through temperate glaciers

Abstract

Abstract. Understanding water movement through a glacier is fundamental to several critical issues in glaciology, including glacier dynamics, glacier-induced floods, and the prediction of runoff from glacierized drainage basins. To this end we have synthesized a conceptual model of water movement through a temperate glacier from the surface to the outlet stream. Processes that regulate the rate and distribution of water input at the glacier surface and that regulate water movement from the surface to the bed play important but commonly neglected roles in glacier hydrology. Where a glacier is covered by a layer of porous, permeable firn (the accumulation zone), the flux of water to the glacier interior varies slowly because the firn temporarily stores water and thereby smooths out variations in the supply rate. In the firn-free ablation zone, in contrast, the flux of water into the glacier depends directly The purpose of this paper is to present a conceptual model of water flow through a glacier based on a syn-

Spatially distributed runoff at the grounding line of a large Greenlandic tidewater glacier inferred from plume modelling

“…Fountain and Walder, 1998). Our results do not permit us to differentiate between these morphologies and both may plausibly persist near the terminus of KNS.…”

“…Once in the subglacial drainage system, travel time through the system may vary significantly depending on the state of the hydraulic system (Fountain and Walder, 1998). The cumulative effect of all of these processes will be to delay meltwater from production to entering the fjord.…”

Brief communication: Observations of a glacier outburst flood from Lhotse Glacier, Everest area, Nepal

“…In the Himalaya, a specific subset of outburst floods called glacial lake outburst floods (GLOFs) has received the most attention with respect to hazards, likely because of their potentially large societal impact (e.g., Vuichard and Zimmermann, 1987). In contrast, glacier outburst floods in the Himalaya, herein referring to outburst floods that are not generated by a proglacial lake, have received relatively little attention likely due to their seemingly unpredictable nature, which has resulted in these events rarely being observed (Fountain and Walder, 1998). While they are a known hazard and discussed in the literature (e.g., Richardson and Reynolds, 2000), few studies in Asia have investigated these hazards in detail (Richardson and Quincey, 2009).…”

“…In contrast, glacier outburst floods in the Himalaya, herein referring to outburst floods that are not generated by a proglacial lake, have received relatively little attention likely due to their seemingly unpredictable nature, which has resulted in these events rarely being observed (Fountain and Walder, 1998). While they are a known hazard and discussed in the literature (e.g., Richardson and Reynolds, 2000), few studies in Asia have investigated these hazards in detail (Richardson and Quincey, 2009).Glacier outburst floods can occur sub-, en-, or supraglacially when the hydrostatic pressure of the stored water exceeds the structural capacity of the damming body, when stored water is connected to an area of lower hydraulic potential, when englacial channels are progressively enlarged in an unstable manner, and/or when catastrophic glacier buoyancy occurs (Fountain and Walder, 1998;Richardson and Reynolds, 2000;Gulley and Benn, 2007). For debris-covered glaciers, the drainage of supraglacial ponds commonly occurs through englacial conduits, which facilitate connections to areas of lower hydraulic potential (Gulley and Benn, 2007).…”

“…Glacier outburst floods can occur sub-, en-, or supraglacially when the hydrostatic pressure of the stored water exceeds the structural capacity of the damming body, when stored water is connected to an area of lower hydraulic potential, when englacial channels are progressively enlarged in an unstable manner, and/or when catastrophic glacier buoyancy occurs (Fountain and Walder, 1998;Richardson and Reynolds, 2000;Gulley and Benn, 2007). For debris-covered glaciers, the drainage of supraglacial ponds commonly occurs through englacial conduits, which facilitate connections to areas of lower hydraulic potential (Gulley and Benn, 2007).…”