Prior to the twentyfirst century however, the hydrology of the gris had received little attention, with the excep. Glacierpermafrost hydrology interactions, bylot island, canada b. Hydrology of a polythermal glacier, erikbreen, northern. Specific storage is determined by dividing the stored volume by the area of the 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.
Study guide for mass balance, glacial hydrology, glacial flow. Notably absent is any consideration of polythermal. Temperature measurements show a polythermal structure with subglacial water trapped by the cold lowest part of the glacier 2 c. Notes on glacier hydrology mccarthy summer school, 2016. Glacierfed rivers provide much of the water supply in some parts of the world. The recent, growing concern over the future response of polar glaciers and ice sheets to forecasts of a warming climate and lengthening summer. 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. A pdf version of this document can be downloaded from. 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. Polythermal glacier studies in svalbard determined by ground. Mechanics and thermodynamics of polythermal glaciers.
However, much of the contemporary knowledge relating to glacier hydrology has been based upon, and conditioned by, understanding gleaned from temperate valley glaciers. 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. However, the interplay of factors governing its spatial and temporal variations such as. Hydrobiogeochemical coupling beneath a large polythermal. Notably absent is any consideration of polythermal bed conditions and content related expressly to the basal hydrology of antarctica. Glacierpermafrost hydrology interactions, bylot island. Polythermal glaciers, svalbard department of geography.
Polythermal glacier studies in svalbard determined by. 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. Spatial and temporal variations in glacier hydrology on. Linksbetween shorttermvelocity variations and the subglacial hydrology ofa predominantlycold polythermal glacier lukecopland,1martinj. Drainagesystem development in consecutive melt seasons at.
Glacial conditions that contribute to the regeneration of. Dec 01, 2011 the manner by which meltwater drains through a glacier is critical to ice dynamics, runoff characteristics, and water quality. 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. Here, we show that the lower part of the ablation area of khumbu glacier, a highelevation debriscovered glacier in nepal, may contain 56% temperate.
Mapping thermal and hydrological conditions beneath a polythermal glacier with radioecho sounding. Polythermal glacier hydrology and ice flow dynamics. The influence of snow cover thickness on the thermal regime. Hydrology and dynamics of a polythermal mostly cold high arctic. The drainage pattern of hansbreen and werenskioldbreen. 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. Polythermal structure of a himalayan debriscovered. Glacial and glaciohydrologic processes that control the glaciofluvial sediment delivery from erikbreen, a polythermal glacier on the north coast of spitsbergen.
Ice caps have an area less than 50,000 km 2 19,000 sq mi by definition. These observations suggest that hydrologically forced variations in glacier flow may be common even in mostly cold glaciers, but the details of the hydrology. In the accumulation and upper ablation areas, where ice is predominantly coldbased, summer velocities were slightly higher than overwinter velocities. A glacier that fills a valley is called a valley glacier, or alternatively an alpine glacier or mountain glacier. A large body of glacial ice astride a mountain, mountain range, or volcano is termed an ice cap or ice field. Variations in the thermal regimes of glaciers, and their implications for drainage, are first addressed. Dezember 1977 citizen of seelisberg switzerland accepted on the recommendation of prof. 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. Recent advances in our understanding of the role of. Polythermal glacier hydrology and ice flow dynamics request pdf. The distribution of basal motion beneath a high arctic. 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. Agriculture canadian prairies, central asia hydroelectrical power production iceland, france, switzerland, norway. The northern margin of the glacier has a 510 m high ice cliff, from which large blocks fall dry calving.
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. Meltwater tends to follow supra and englacial routes and welldeveloped basal hydrological networks are rare. A cutandclosure origin for englacial conduits in uncrevassed regions of polythermal glaciers volume 55 issue 189 j. Thus, it is hypothesized that interconnection between glacial and subsurface permafrost hydrological systems does occur in polythermal glacier systems. 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. A glacier that has a mixed basal thermal regime, consisting of both warm ice at 0c and cold ice below 0c. Notes on glacier hydrology mccarthy summer school, 2016 contents. Boon and sharp 2003 observed ponding and drainage events on a polythermal. Pdf the hydrology of glaciers concerns the transfer of meltwater through an ice mass. The polythermal structure has major implications for glacier hydrology, ice. A glacier forms where the accumulation of snow exceeds its ablation melting and sublimation over many years, often centuries. Nienow2 1department ofearthandatmosphericsciences,university albertaedmonton,albertat6g2e3canada email. Apr 27, 2000 in this paper we describe three sources of information that radioecho sounding has provided about the subsurface hydrology of a polythermal glacier.
Glacier hydrology is the study of the flow of water through glaciers. 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. Hydrology and dynamics of a polythermal mostly cold high arctic glacier robert g. A separate trajectory of model development was motivated by the recognition that the retention, evacuation and distribution of subglacial water is a. 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. Glacierpermafrost hydrology interactions, bylot island, canada. Earth surface processes and landforms high arctic glacier. Understanding the expected dynamic range of a glaciers hydrological system is best studied by in situ. The manner by which meltwater drains through a glacier is critical to ice dynamics, runoff characteristics, and water quality. The drainage pattern of hansbreen and werenskioldbreen, two. 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. In this paper, the hydrology of glaciers in the higharctic archipelago of svalbard is examined.
The drainage pattern of hansbreen and werenskioldbreen, two polythermal glaciers in svalbard anja palli, john c. 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. Radioecho sounding determination of polythermal glacier hydrology. Glaciologists believe that many glaciers in svalbard are polythermal, i. Polythermal glacier regimes are a common, characteristic response in regions with protracted subfreezing winter air temperatures where. Moorman earth science program, university of calgary, calgary. In this paper we describe three sources of information that radioecho sounding has provided about the subsurface hydrology of a polythermal glacier. 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. Linksbetween shorttermvelocity variations and the subglacial. Links between shortterm velocity variations and the subglacial hydrology of a predominantly cold polythermal glacier. However, much of the contemporary knowledge relating to glacier hydrology has been based upon, and conditioned by, understanding gleaned. Palli, anja, polythermal glacier studies in svalbard determined by groundpenetrating radar department of geosciences, university of oulu, p. Identify the ways ice mass accumulates and ablates.
Measurements at polythermal john evans glacier, ellesmere island, indicate strong links between spatial and temporal variations in subglacial hydrology and changes in surface velocity. Study site john evans glacier is a polythermal valley glacier on the east coast of ellesmere island, nunavut, canada 7940n, 743ow. The distribution of basal motion beneath a high arctic polythermal glacier volume 49 issue 166 luke copland, martin j. 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. 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. Hydrology of ice sheets most of the interior of large ice sheets frozen to the bed. Water flow climate local meteorology surface mass and energy exchange net mass balance dynamic response changes in geometry effect on landscape. Radioecho sounding determination of polythermal glacier. Next to the glacier is a sediment apron and there is a braid plain around the lake. Glacier hydrology in svalbard, norwegian high arctic. Polythermal structure of a himalayan debriscovered glacier.
Globally, a significant proportion of glaciers and ice sheets exhibit nontemperate thermal regimes. Globally, a significant proportion of glaciers and ice sheets exhibit nontemperate thermal. The influence of snow cover thickness on the thermal. Proglacial icings are one of the most common forms of extrusive ice found in the canadian arctic. Mechanics and thermodynamics of polythermal glaciers a dissertation submitted to the eth zurich for the degree of doctor of sciences. Study guide for mass balance, glacial hydrology, glacial flow a.
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