Water flow climate local meteorology surface mass and energy exchange net mass balance dynamic response changes in geometry effect on landscape. Palli, anja, polythermal glacier studies in svalbard determined by groundpenetrating radar department of geosciences, university of oulu, p. Spatial and temporal variations in glacier hydrology on. Boon and sharp 2003 observed ponding and drainage events on a polythermal. Next to the glacier is a sediment apron and there is a braid plain around the lake. Apr 27, 2000 radioecho sounding determination of polythermal glacier hydrology radioecho sounding determination of polythermal glacier hydrology copland, luke 20000427 00. Meltwater tends to follow supra and englacial routes and welldeveloped basal hydrological networks are rare. Mechanics and thermodynamics of polythermal glaciers a dissertation submitted to the eth zurich for the degree of doctor of sciences presented by andreas aschwanden dipl. Linksbetween shorttermvelocity variations and the subglacial hydrology ofa predominantlycold polythermal glacier lukecopland,1martinj.
However, much of the contemporary knowledge relating to glacier hydrology has been based upon, and conditioned by, understanding gleaned. Hydrology of ice sheets most of the interior of large ice sheets frozen to the bed. The focus of the aberystwyth team, in association with the universities of leeds, bristol, and swansea has been to record icestructures with a view to establishing. Polythermal structure of a himalayan debriscovered. However, warm zones in a polythermal glacier and taliks within icerich permafrost can enable the establishment of groundwater flow and the formation of subsurface conduits.
Notably absent is any consideration of polythermal. Through the upsurge in interest in polythermal glacier hydrology, coupled with the recent developments in data acquisition and theoretical developments, and similarities alluded to here, sharp et al. The influence of snow cover thickness on the thermal regime. David m hannah and angela m gurnell, a conceptual, linear reservoir runoff model to investigate melt season changes in cirque glacier hydrology, journal of hydrology, 10. Polythermal glacier hydrology and ice flow dynamics request pdf. The drainage pattern of hansbreen and werenskioldbreen, two polythermal glaciers in svalbard anja palli, john c. A cutandclosure origin for englacial conduits in uncrevassed regions of polythermal glaciers volume 55 issue 189 j.
Polythermal glacier hydrology and ice flow dynamics. Polythermal glacier regimes are a common, characteristic response in regions with protracted subfreezing winter air temperatures where. In the accumulation and upper ablation areas, where ice is predominantly coldbased, summer velocities were slightly higher than overwinter velocities. Mechanics and thermodynamics of polythermal glaciers. Glacial conditions that contribute to the regeneration of fountain glacier proglacial icing, bylot island, canada pablo wainstein,1,2 brian moorman1 and ken whitehead1 1 department of geography, university of calgary, alberta, canada 2 bgc engineering, calgary, alberta, canada abstract.
Glacierpermafrost hydrology interactions, bylot island, canada b. In this paper, the hydrology of glaciers in the higharctic archipelago of svalbard is examined. Request pdf polythermal glacier hydrology and ice flow dynamics measurements at polythermal john evans glacier, ellesmere island, indicate strong links between spatial and temporal variations. Understanding the expected dynamic range of a glaciers hydrological system is best studied by in situ.
Dec 01, 2011 the manner by which meltwater drains through a glacier is critical to ice dynamics, runoff characteristics, and water quality. It is a mysterious world, where water running on the surface of the glacier disappears through cracks and holes in the glaciers, and powerful rivers emerge from the glacier snout1. Glacier hydrology in svalbard, norwegian high arctic. Polythermal glaciers, svalbard department of geography. Pdf the hydrology of glaciers concerns the transfer of meltwater through an ice mass. Identify the ways ice mass accumulates and ablates. Read radioecho sounding determination of polythermal glacier hydrology, proceedings of spie on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Glacierpermafrost hydrology interactions, bylot island, canada. A glacier forms where the accumulation of snow exceeds its ablation melting and sublimation over many years, often centuries.
Nov 14, 2018 runoff from highelevation debriscovered glaciers represents a crucial water supply for millions of people in the hindu kushhimalaya region, where peak water has already passed in places. Globally, a significant proportion of glaciers and ice sheets exhibit nontemperate thermal regimes. Hydrology and dynamics of a polythermal mostly cold high arctic glacier robert g. The distribution of basal motion beneath a high arctic. Polythermal glacier studies in svalbard determined by ground. The recent, growing concern over the future response of polar glaciers and ice sheets to forecasts of a warming climate and lengthening summer. Radioecho sounding determination of polythermal glacier hydrology. A large body of glacial ice astride a mountain, mountain range, or volcano is termed an ice cap or ice field.
Glaciologists believe that many glaciers in svalbard are polythermal, i. Moorman earth science program, university of calgary, calgary. Yet there is a need to improve understanding of polythermal glacier hydrology in particular, since nontemperate ice ice below the pressuremelting temperature, lacking interstitial water is commonly encountered in highlatitude ice masses irvinefynn et al. Notes on glacier hydrology mccarthy summer school, 2016 contents. Recent advances in our understanding of the role of. Glacier hydrology is the study of the flow of water through glaciers.
Hydrology of a polythermal glacier, erikbreen, northern. Nienow2 1department ofearthandatmosphericsciences,university albertaedmonton,albertat6g2e3canada email. Proglacial icings are one of the most common forms of extrusive ice found in the canadian arctic. Notes on glacier hydrology mccarthy summer school, 2016. Glacial and glaciohydrologic processes that control the glaciofluvial sediment delivery from erikbreen, a polythermal glacier on the north coast of spitsbergen. Measurements at polythermal john evans glacier, ellesmere island, indicate strong links between spatial and temporal variations in subglacial hydrology and changes in surface velocity. The distribution of basal motion beneath a high arctic polythermal glacier volume 49 issue 166 luke copland, martin j. The drainage pattern of hansbreen and werenskioldbreen. Earth surface processes and landforms high arctic glacier. Box 3000, fin90014 university of oulu, finland oulu, finland 2003 abstract the overall aim of this thesis is to emphasise how ground penetrating radar gpr can be used in. Radioecho sounding determination of polythermal glacier. Mechanics and thermodynamics of polythermal glaciers a dissertation submitted to the eth zurich for the degree of doctor of sciences. Ice caps have an area less than 50,000 km 2 19,000 sq mi by definition.
A glacier named midre lovenbreen in nw spitsbergen is a typical polythermal glacier, and here norwegian glaciologists have obtained a massbalance record that spans some 35 years. The influence of snow cover thickness on the thermal. However, the interplay of factors governing its spatial and temporal variations such as. Dezember 1977 citizen of seelisberg switzerland accepted on the recommendation of prof. The manner by which meltwater drains through a glacier is critical to ice dynamics, runoff characteristics, and water quality. Polythermal structure of a himalayan debriscovered glacier. Prior to the twentyfirst century however, the hydrology of the gris had received little attention, with the excep. The northern margin of the glacier has a 510 m high ice cliff, from which large blocks fall dry calving. The drainage pattern of hansbreen and werenskioldbreen, two.
Links between shortterm velocity variations and the subglacial hydrology of a predominantly cold polythermal glacier. The lithology is mainly sedimentary, with the upper catchment and headwalls consisting of precambrian carbonates, phyllite and quartzite, permian sandstones, dolomite and limestones and the rest of the catchment comprising triassic to cretaceous siltstones. Study site john evans glacier is a polythermal valley glacier on the east coast of ellesmere island, nunavut, canada 7940n, 743ow. Specific storage is determined by dividing the stored volume by the area of the glacier. A pdf version of this document can be downloaded from.
Temperature measurements show a polythermal structure with subglacial water trapped by the cold lowest part of the glacier 2 c. A glacier that has a mixed basal thermal regime, consisting of both warm ice at 0c and cold ice below 0c. Agriculture canadian prairies, central asia hydroelectrical power production iceland, france, switzerland, norway. Here, we show that the lower part of the ablation area of khumbu glacier, a highelevation debriscovered glacier in nepal, may contain 56% temperate. The polythermal structure has major implications for glacier hydrology, ice. Glacierpermafrost hydrology interactions, bylot island. However, much of the contemporary knowledge relating to glacier hydrology has been based upon, and conditioned by, understanding gleaned from temperate valley glaciers. Notably absent is any consideration of polythermal bed conditions and content related expressly to the basal hydrology of antarctica. These notes focus on glacier hydrology with a strong bias toward the basal drainage system and the formulation of basal hydrology models for the purpose of coupling with models of ice ow. Glacierfed rivers provide much of the water supply in some parts of the world. These observations suggest that hydrologically forced variations in glacier flow may be common even in mostly cold glaciers, but the details of the hydrology. Study guide for mass balance, glacial hydrology, glacial flow a. Mapping thermal and hydrological conditions beneath a polythermal glacier with radioecho sounding. Thus, it is hypothesized that interconnection between glacial and subsurface permafrost hydrological systems does occur in polythermal glacier systems.
A separate trajectory of model development was motivated by the recognition that the retention, evacuation and distribution of subglacial water is a. Drainagesystem development in consecutive melt seasons at. Study guide for mass balance, glacial hydrology, glacial flow. Hydrology and dynamics of a polythermal mostly cold high arctic. Linksbetween shorttermvelocity variations and the subglacial. Large net losses from storage in the first half of the interval give high and variable discharge, whereas there are moderate net storage gains when discharge is low and invariable in the second half. Polythermal glacier studies in svalbard determined by. Variations in the thermal regimes of glaciers, and their implications for drainage, are first addressed. A glacier that fills a valley is called a valley glacier, or alternatively an alpine glacier or mountain glacier.
The longitudinal pattern of surface velocity of a large, predominantly cold, polythermal glacier john evans glacier, ellesmere island, canada was measured over summer and winter periods. Lakes on the surface, linked by persistent, deeply incised meltwater streams, are hallmark features of cold ice in the ablation zone of a glacier or ice sheet. Glacial conditions that contribute to the regeneration of. Hydrobiogeochemical coupling beneath a large polythermal.
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