Theses - Scott Polar Research Institute

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Embargo
A historical geography of Halley research station, Antarctica, 1956 – present
Oates, Alice
This thesis investigates the historical geographies of Halley research station, a British research station in East Antarctica. This study is the first in-depth history of Halley station, a site unique even among the already remarkable category of Antarctic research stations. Established for the International Geophysical Year of 1957-58, just a few years before the signing of the Antarctic Treaty in December 1959, Halley is deeply connected to one of the most important periods of change in Antarctic science and governance. It is also a geophysical observatory with a scientific record that includes the discovery of the hole in the ozone layer, connected to an international community of scientists through its atmospheric and space weather programmes. Halley is also a place where people live and work, whether for a summer, a winter, or multiple seasons. Through its exploration of these facets of Halley’s past and present, the thesis contributes to scholarship on the history of Antarctic science and governance, life and work in extreme environments, and the connections between Antarctica and the world beyond the ice. More broadly, it contributes to historical geographical scholarship on people and places of science, and human engagements with remote and extreme environments. The primary source material consists of archival records and in-depth interviews. The subsequent analysis of this material is structured thematically around four answers to the central question of this thesis: What is Halley? Halley is characterised by constant change; there have been four ‘Halleys’, situated on a floating ice shelf in constant motion, populated by an ever-changing group of scientists and technical/support staff. Grappling with the issue of identity through change, the thesis examines four ‘identities’ of Halley: an International Geophysical Year legacy, lived infrastructure, colonial settlement, and geophysical observatory. In doing so, the thesis also draws on different theoretical frameworks: assemblage, scientific boundary work, settler colonial studies, and history of science. Overall, this thesis contributes an in-depth case study to research on the people, places, and politics of science in extreme environments.
Open Access
Who Counts? A Critical Approach to Indigenous Language Demography in the Yukon
Palmer, Leah
Language demography is the practice of counting speakers of different languages. It is a common discourse technique used when discussing Indigenous languages around the world. However, there is much debate and controversy over how language demography should be practiced, to produce accurate numbers of speakers, and to produce data that is relevant and useful to those working in Indigenous language revitalisation. Alongside this debate on language demography, recent years have seen the emergence of the Indigenous Data Governance (IDG) movement. The IDG movement asks researchers to address the historical wrongdoings against Indigenous people for the sake of ‘research’, by ensuring Indigenous people have control over the research they are a part of, and access to the data that comes from that research. Indigenous organisations and researchers working within IDG frameworks argue that giving Indigenous people control of research processes concerning them, and the ability to own and freely access their own data, produces data that is more accurate, relevant, and useful to Indigenous people. The language demography debate and the IDG movement have proceeded entirely separately until this dissertation. This dissertation examines six demographies of First Nations languages in the Yukon through the lens of IDG principles, to discover how IDG influences the data collected in language demographies, within the unique context of the First Nations self-governance movements of the Yukon. It is the first study to examine the intersection of language demography and IDG. A combination of document analysis of the methodology of different language demographies, data analysis of the demographies, and attempts at interviews with language revitalisation experts working in the Yukon are used. It is found that incorporating principles of IDG into the methodology of language demographies from the start changes the nature of the data that they collect; what data is collected (who counts as a speaker?), how it is collected (who counts the speakers?), and how the data is accessed and stewarded. Incorporating IDG into language demographies produces data that is more accurate, relevant, and useful to First Nations communities. This is because IDG empowers communities to collect the data that is most relevant for their priorities, reduces the harmful effects of extractive research, and enables communities to have free access to their own data. However, there also exist significant barriers to the full implementation of IDG in language demographies. The future of language demography in Indigenous communities must work to dismantle those barriers and to incorporate principles of IDG.
Embargo
On Indigenous Tax Consciousness: The Socio-Legal History of the Native Village of Venetie Tribal Government, 1938-1987
Zahnd, Maximilien
This thesis explores the relationship between taxation, Indigenous sovereignty, and settler colonialism. Specifically, it chronicles the socio-legal history of the Native Village of Venetie Tribal Government, a Gwich’in tribe from the Alaska interior region. The tribe gained national attention when it attempted to tax a school construction project in the 1980s, triggering a fierce but ultimately unsuccessful judicial battle with the state of Alaska. The thesis seeks to answer the following research questions: How does a tribe develop the idea to use taxation, and why does it decide to use it? The thesis thus strives to explore the origins and contours of what I call ‘Indigenous tax consciousness’. Drawing on archival and field research, I argue that a tribe’s tax consciousness consists of a long and delicate process that often takes years to crystallize. It requires a favorable politico-legal climate, good timing, a few key individuals, and some serendipity. Most importantly, however, Indigenous tax consciousness goes hand in hand with a profound desire to seek political, economic, and cultural empowerment.
Open Access
The Rise of a Technoscientific Third Pole: Environmental Data Practices in High Mountain Asia
Patel, Samira
Recent studies have revealed decades of glacial melt in the Hindu Kush Himalayas and Tibetan Plateau (“High Mountain Asia”). A region with a dearth of in-situ environmental data and opaque, fragmented governance, remote sensing data plays a key role in uncovering the region’s environmental concerns. These range from disasters such as flooding and earthquakes that have devastated the region to the glacial melt that impacts water supply for local livelihoods and agricultural systems. In this growing environmental discourse surrounding High Mountain Asia (HMA), analogies such as “water tower of Asia” and “Third Pole” have become correspondingly popular. The focus of this dissertation is on how the International Centre for Integrated Mountain Development (ICIMOD), an intergovernmental organization, participates in region-building. Primarily this dissertation focuses on ICIMOD’s efforts to respond to concerns over the lack of environmental data in the region, and critically examines the role of environmental data and its use in environmental governance. This dissertation engages in science and technology studies, geographies of science, and institutional ethnography in order to understand the confluence of region-building in a highly contested space and a growing focus on environmental monitoring programs due to the region’s sensitivity to climate change, natural disasters, and infrastructure development. One might consider HMA far from the usual suspects of a study on technoscientific practices. Typically sites such as Silicon Valley or the Antarctic are recognized as principal producers of science and technologies. However, it is in a region like HMA where conceptions of scientific knowledge are most deeply felt. Where ideas and policies of climate change debated in global scientific communities have deep ramifications for millions of people vulnerable to its impacts living in the high mountains or relying on its resources downstream. The diversity of these communities and the landscapes they inhabit problematize the epistemologies of climate change knowledge production. How does one capture such diversity in the understanding of environment? Therefore, it becomes impossible to consider these technoscientific methods without placing them within a broader pluralistic understanding of the mountain environment.
Open Access
Natural Resources Development in the Republic of Sakha: Russia's Diamond Producing Region
Tichotsky, John
This thesis is an empirical study of a regional economy that is undergoing rapid social and economic change. The principal objective of the thesis is to advance a comprehensive view of past and present development of the Republic of Sakha, using available economic and historical information. The Republic of Sakha (Yakutia) is one of Russia’s most resource-rich regions, the political unit with the largest land area within the Russian Federation, and a region with a particularly strong, ethnically-based local government. The current economic structure of the Republic of Sakha is primarily defined by an export-based diamond industry. In Sakha, enormous real and potential windfall from natural resource development amplifies the existing chaos, typical in Russia, caused by the tangle of economic transition, regionalism, ethnic politics, and corruption. The last one hundred years of development and reform in the Republic of Sakha can be addressed by a unified explanation. This thesis proposes that, rather than create a new paradigm in development economics, the Sakha case study is extremely consistent with existing explanations of a subset of economies that rely heavily on export-led growth of primary resource production. Historical evidence suggests that the successive development of specific natural resources ("staples”) for use or sale outside the republic defines the development of the Republic of Sakha since the I9th century and throughout the entire Soviet period. The current state of Sakha's general economy, the recent changes in the structure of this economy and the performance of the main industries and firms continue to function through the exploitation and export of the region’s natural resources. The process of privatization and the mechanism for export and sale of resource production are paramount issues in understanding the current structure of the Sakha economy. Management of natural resource rents is closely linked with the current and future possibilities for the Republic of Sakha to achieve long-term economic growth and significantly higher standards of living for the people living within the region. Different views about Sakha’s development are discussed in the context of development policy. A comparison is made between available options for Sakha’s development and management of resource rents with parallel choices made in the State of Alaska (United States).
Open Access
Natural resource development after Perestroika: Gold and tin mining in the Russian Northeast
Tichotsky, John
In this thesis I will examine the process of economic and political decentralisation in Russia by looking at the current changes affecting the gold and tin mining industry of the Russian Northeast. These processes are linked with an alternation of authoritarianism and liberalism, and to general attitudes about economic factors of production. The mining industry, the Russian Northeast's principal economic sector, originated as an integral part of the Stalinist labour camp system and faces great problems functioning in the post-*perestroika* world. These problems include: conflicts between the centre (Moscow) and the region, falling mineral production, difficulties in privatising the mining industry, a recent large emigration of non-Native people, and difficulties in addressing the concerns of indigenous people and environmentalists.
Open Access
Wrangell Island: From political conflict to Russian sovereignty
Vdovenko, Anna
This dissertation describes the discovery, exploration and mapping of Wrangell and Herald Islands. Political disputes about sovereignty over the islands will be examined from the early 20th century until the present. The attempts at early settlement by Canadian, United States and Russian parties are described. Regarding current plans for the National Reserve, a brief explanation will be given of scientific themes relevant to the islands and their future, such as biology and geology. The analysis of the sovereignty disputes will demonstrate effective de facto sovereignty by Russia. If the Russian government proceeds with conservation policies, the islands may qualify as the first World Heritage Site in the Arctic regions. This designation would permit Russia to advance Arctic conservation achievements, thus allowing Wrangell Island and Herald Island to assume an important place comparable with other World Heritage Site islands such as the Galapagos, Aldabra and Heard Island. This would facilitate conclusion of a Treaty with the United States Government which would thence annul any basis for contention over sovereignty, thus confirming the de jure rights of Russia.
Open Access
Water flow beneath past ice sheets
Kirkham, James; Kirkham, James [0000-0002-0506-1625]
The movement of water beneath ice sheets exerts an important, yet poorly understood, control on how ice masses respond to climatic warming. However, the subglacial realm of ice sheets is one of the most inaccessible environments on Earth. Consequently, little is known about the processes that operate beneath today’s ice masses — and how these will evolve in the future. Subglacial landforms present in formerly-glaciated regions provide comparatively accessible records of glacial erosion, deposition, and sediment transport beneath ice sheets that have undergone deglaciation. This thesis investigates the potential of these landforms to reconstruct the flow of water beneath past ice sheets as analogues for how contemporary ice masses will evolve in a warming climate. A combination of geophysical approaches, including multibeam-bathymetric surveys, high-resolution 3D seismic-reflection data, conventional 3D seismic-reflection data, and geotechnical information from boreholes, is used to investigate the flow of water beneath ice sheets which covered western Europe and more expansive regions of the Antarctic continental shelf in the past. These data are first used to constrain the routing and fluxes of subglacial water beneath the retreating West Antarctic Ice Sheet. The impact of subglacial water flow on ice-sheet dynamics during deglaciation is then examined by imaging the internal structures of ancient channels incised by meltwater — tunnel valleys — in the North Sea. The unprecedented detail provided by the high-resolution 3D seismic-reflection data provides links between ice-sheet dynamics and subglacial meltwater flow during deglaciation. A numerical modelling approach constrains these linkages further by estimating the time that the meltwater channels take to form beneath deglaciating ice sheets. Finally, the sedimentation patterns resulting from subglacial water flow and other glacially-influenced processes during deglaciation are examined. Greater coverage of geophysical data on formerly glaciated continental margins, combined with chronological constraints from shallow drilling, will improve understanding of the hydrological systems and dynamics of former and contemporary ice sheets.
Open Access
Inuit Harvesting Strategies in the Canadian Arctic and Implications for Wildlife Management
(1987-06) Netherwood, Marshall
The thesis analyses two topics: native harvesting strategies and selected cases of over-exploitation. Its purpose is to assess the credibility of the assumption that hunter-gatherer societies do not have a system of self-regulation. Theoretical explanations and models are described to elicit underlying principles and coherent systems in hunter-gatherer harvesting strategies and adaptation processes. Two annual cycles of the Netsilik Inuit are discussed and examined in a formal theory model to analyse what changes and effects occurred when the rifle was introduced to their subsistence economy. The evidence supporting the Pleistocene overkill theory and the claim that hunters over-exploited some of the major barren-ground caribou herds in the Northwest Territories is examined. The evidence is found to be unproven and inconclusive. The nature of self-regulation in hunter-gatherer societies as supported by ethnographic literature is described and determined to be extant. Hunters practice control in harvesting through the acquired knowledge and institutional means to monitor and avert overhunting. It is also evident that harvesters have a sound basis of knowledge and expertise in animal ecology. In the appendix. four cases are described where the traditional system of harvesting/management has proven successful and superior to state imposed wildlife management. The thesis concludes that the assumption is erroneous: there exists a socially-constructed system of self-regulation. The implications for wildlife management are discussed and it is concluded that although there is greater recognition of the native system of harvesting/management today, it is not generally accepted that they possess the knowledge and expertise to organize an effective management strategy.
Open Access
Transporting Liquified Natural Gas by Surface Ships from the North Slope of Alaska to World Markets
(1995-06) Wubbold III, Joseph Henry
This thesis reports the work that has been done in Alaskan waters on ship transits; gives examples of a system that has worked in the past - the Winter Navigation Program on the American Great Lakes - and two that are operating now, the Baltic, and the Russian Northern Sea Route in greater detail; discusses problems with ice: how to find it, and determine its characteristics; and how to decide on routing using various ice reconnaissance techniques. Vessel types and their special construction are discussed. In the chapter on operational considerations, the concept of ice-strengthened carriers under icebreaker escort is elaborated. The thesis continues with discussions of command and control arrangements, training and certification of crews, and environmental and regulatory issues. It closes with recommendations for further study, and summarized conclusions. Much of the material, especially on ship management, command and control, and relationships with regulatory bodies and environmentalists is based on the author's own experience. That experience includes command of several U.S. Coast Guard ships including a polar icebreaker, experience in the Winter Navigation Program on the American Great Lakes as an icebreaker captain, convoy commander on a number of convoys, and as a field commander of one of the operational sectors. Duties have also involved both writing Federal regulations when in a staff position, and enforcing Federal statutes and regulations in command positions afloat and ashore. That experience has led to certain biases, which are indicated as appropriate.
Open Access
An Evaluation of British Royal Naval Arctic Exploration Techniques: 1818-1876
(1986-06) Ellis, Robert Dean
Fridtjof Nansen, one of the greatest arctic explorers of all time, achieved immeasurable success in the field of arctic exploration, based on his employment of indigenous arctic peoples' methods of travel and survival in cold regions. The Royal Navy, in a burst of arctic exploration between the years 1818-18?6, achieved great success too in mapping over one-half of the North American and Canadian Arctic, where the main effort of exploration was centred, and in the discovery of three Northwest Passages. But this was at considerable effort and a very high monetary cost. J. Rae, J. Richardson, and R. King in the 184Os and '50s, and more recently V. Stefansson (1939) and H.N. Wallace (1980), have put forward the view that the navy did not give full consideration to indigenous "light" methods and the concept of "living off the land", or even to a European application of this approach. In addition, they believed the navy had a "British is best" attitude to arctic exploration. Wallace (1980) views naval arctic exploration in terms of a "heavy, deep-sea" approach which was out of harmony with the arctic environment. Another school of thought, typified in the writings of L.H. Neatby (1958 and 1970), extols the techniques used by the navy. This thesis assesses the "heavy, large-scale, deep-sea"approach of the navy while revealing that far more respect was given to, and much initiative was shown regarding the employment of, proven indigenous techniques; and that the navy showed more awareness of, and adaptability to, the environment than they are sometimes given credit for. The thesis will focus on the seaborne exploration of the North American and Canadian Arctic as opposed to the overland approach, as the main thrust of naval exploration was via the sea, based from ships in search of a Northwest Passage. (As the techniques employed show a clear development over time, a chronological approach is adopted).
Open Access
Small scale, community based economic development in the Canadian Arctic
(1987-06) Robinson, Graham
The term "northern development" in the Canadian Arctic is often associated only with large, non-renewable resource extraction projects. Other alternative development projects such as the co-operatives provide development on a scale that a community itself can manage and control. The "boom and bust" cycle of mega project development has been of little benefit to Inuit community development and the current "bust" in the Canadian Beaufort Sea oil and gas exploration activity is a case in point. A more sustainable, alternative development strategy is provided by small scale, community based economic development.
Open Access
Scientific achievements by Antarctic expeditions in the aftermath of the Sixth International Geographical Congress: 1895-1905
(1998-06) Salveson, Kirk
The third resolution passed at the International Geographical Congress, held in London in 1895, is reviewed in the light of its scientific goals and subsequent achievements. Seven Antarctic expeditions from six countries are analyzed in terms of their objectives, scientific staffs, and academic disciplines. Comparisons are made of the success of the early expeditions (1895-1905) of the Heroic Age of Antarctic exploration and some simple quantitative as well as qualitative judgments are attempted. It is acknowledged that the motivations of Antarctic expeditions at this time were complex, but the conclusion is drawn that science played an important role alongside nationalism, heroism, and to a lesser extent commerce, in this period of Antarctic exploration.
Open Access
Development of Dental Services for Arctic Populations: Labrador and the Baffin Region Compared
(1987-06) Dickson, Robin D.B.
This thesis outlines the problems which I perceived in the administration of oral health services for the Baffin Region, North West Territories when working there in 1985 and 1986. The recommendations are suggestions for some solutions. Part I provides a background by describing the elements of public dental health and their relevance to the north. A comparison is made in Part III with similar services provided by the Grenfell Regional Health Services in northern Newfoundland and Labrador, not only because of the broad parity between the two regions but also because of my previous equivalent working knowledge of them from 1983 to 1985. Some specific features from other parts of the circumpolar north are used to reinforce the points raised within the recommendations. Part II and IV are based on personal experiences; they contain opinions which have been substantiated as fully as possible within the time limits of this thesis. The general conclusions are that there is a) inadequate leadership in dental administration throughout the Canadian North West Territories. b) For much of the north and specifically the Baffin Region, promoting private oral health care may not be the best solution to the problems, particularly when there has been previously inadequate administration of the public service and failure to identify and correct any of its supposed faults.
Open Access
Komi reindeer herding: mobility and land use in a changing natural and social environment
(2006-05) Dwyer, Mark James
Nomadic pastoralism is a form of animal husbandry characterised by movement. Herders and their animals move across the tundra and taiga displaying a curious dichotomous relationship of control by and response to each other. This field based research - carried out among Komi nomadic reindeer herders of the Russian far north - examines how Komi pastoral nomads choose a particular time, route and length of migration. This was explored by using anthropological as well as ecological methods to (i) identify how social and political change and environmental variability influence the reindeers’ and herders’ movements alike and (ii) examine how nomadic movements occur in relation to nonecological and ecological factors. It was found that there were essentially two types of human / animal movements; individual movements (made by the duty herder and his herd) and collective movements (made by the brigade). Both types of movement, in time and space, were fundamentally dependent upon herding skill and knowledge, and herd control: (a) the duty herder’s ability to maintain herd cohesion and (b) the general aim of preventing harm befalling the herd (by avoiding dangerous terrain). The duty herder’s selection of pastures was, therefore, made mainly according to where reindeer were the easiest to control. It was also found that individual movements could best be understood as emanating from the interplay between reindeer behaviour and the duty herder’s actions. This interplay is best described as being the duty herder’s skilful perception of and response to ethological changes, as advocated by Tim Ingold. Its main principle is based on the duty herder’s maintenance of herd cohesion, within a restricted territory, which has minimal impact upon reindeer behaviour, and which is achieved through skilful manoeuvring. Collective movements could best be described as a means of providing duty herders with the necessary space in which to manoeuvre their herds with the minimum recourse to herding techniques (such as grouping and re-grouping, stopping and turning the herd), and the avoidance of undesirable pasturing areas. Consequently, it is not by analysing the impact that individual factors have upon the nomadic collective (i.e., nomads and animals) as a whole, that nomadic pastoralist movement will be understood. A new model for analysing nomadic pastoralist movement - focusing on the interrelations between nomads and their animals and the impacts that individual factors have upon it - is proposed.
Open Access
Marine-terminating outlet glacier response to hydrological mechanisms: A comparative study at Store Glestcher and Rink Isbrae, Uummannaq Bay, West Greenland
(2015-06) Nathan-King, Helena
The dynamics of marine-terminating outlet glaciers on the Greenland Ice Sheet are of crucial importance with their principal role in draining the ice sheet. Much work has focused on determining the processes and mechanisms influencing their flow, with most focus on terminus processes, whilst little attention has been paid to the effects of hydrological processes via surface runoff and supraglacial lake drainage. There has been increasing evidence for the influence of enhanced meltwater inputs on impacting short term velocity at marine-terminating outlet glaciers with contrasting responses at individual glaciers. This study uses a remote sensing approach to characterise supraglacial lakes and their volumes at Store Gletscher and Rink Isbrae, two marine-terminating outlet glaciers in West Greenland, to assess the influence of such processes on their flow, providing an effective comparison due to their contrasting geometries, despite similar environmental controls. At Store there is evidence of a strong influence of hydrological mechanisms on its summer velocity variability, supporting observations in previous work with a transition to efficient drainage. However, the opposite is identified at Rink. This difference is suggested to be caused by Rink’s lower capacity for lake formation with a steeper hypsometry and narrower ablation area compared to Store, reflecting the primary controls of surface topography and surface runoff volume on lake formation. These conclusions reveal the possible significant influence of hydrological mechanisms on flow at marine-terminating margins, whilst also indicating a probable range of responses at different glaciers dependent on glacier-specific factors.
Open Access
Re-mapping the Arctic: contemporary approaches to practising cartography across diverse knowledge traditions
(2015-06) Cohen, Oliver
This thesis examines historical and contemporary debates surrounding the way in which knowledge traditions interact in the Arctic. This is done through examining the theoretical and practical history of cartography, both as a discipline, and as applied to the Arctic. In doing so, I make the argument for an inextricable link between cartography and knowledge production across supposedly different ‘knowledge traditions’, through the privileging of performativity as the primary way of making knowledge, and an understanding of human cognition as inherently spatial and narratological. Based on these understandings, I examine debates within geography and wider social science that might assist the practising of cartography under this philosophy – the possibilities for ‘working with multiple ontologies’. For example I explore the opportunity for working with complex adaptive systems, and suggest that a contemporary understanding of how cyberspace is produced in the Arctic fits in with these philosophies. I also examine those debates that might stand in the way of practice that acknowledges these philosophies of complexity – for example debates about the nature of digital materiality, and of the epistemological / ontological divide. These theories and debates are anchored in the Arctic through the use of historical and contemporary examples concerned with the mapping of space and knowledge primarily in the North American Arctic. Ultimately debating a future for practising cartography in the Arctic is situated within the confines of post-colonial critique, so I examine how we define “counter-mapping”, and where the philosophies outlined above fit into this politically strong tradition. In conclusion I suggest that whilst contemporary theory has much to offer an increasingly digital indigenous Arctic, there remains a partial disconnect between theory and practice that can be addressed through reading this debate.
Open Access
Fibre-optic borehole observations and numerical modelling of complex ice-sheet thermodynamics
Law, Robert; Law, Robert [0000-0003-0067-5537]
Predictions of ice-sheet mass loss, and therefore predictions of global sea level rise, depend sensitively upon how ice-sheet motion is incorporated into numerical models. Using field observations and numerical modelling, this thesis demonstrates that two frequently overlooked processes are central to describing borehole observations of fast ice-sheet motion --- intermediate-scale (<25 m, ⪅2 km) interaction of ice motion with realistic or real bed topography, and modulation of these ice-motion patterns through a basal layer of temperate ice (much softer ice at the pressure-melting point). I first present a fibre-optic data set from a 1,043 m deep borehole drilled to the base of the fast-moving (>500 m a‾¹) marine-terminating Sermeq Kujalleq (Store Glacier) at the western margin of the Greenland Ice Sheet. This reveals hitherto unappreciated complexity in the processes behind fast ice-sheet motion. I observe substantial but isolated strain heating ~220 m beneath the surface within stiffer interglacial-phase ice where previously none was expected. Ice deformation within glacial-phase ice below 889 m is further observed to be strongly heterogeneous, with a possible high-strain interface demarcating the Last Glacial-Interglacial Transition. I also find a 73-m-thick temperate basal layer, notably thicker than the <10-m-thick temperate layer just 8.9 km away, unexplained by existing theory, and interpreted to be important for the glacier's fast motion. To disentangle this observed complexity, I then model three isolated 3D domains from the Greenland Ice Sheet's western margin --- two from Sermeq Kujalleq and one from the land-terminating Isunnguata Sermia, all centred above a central borehole observation. By incorporating high-resolution realistic geostatistically simulated topography, I demonstrate that a layer of basal temperate ice with spatially highly variable thickness forms naturally in both marine- and land-terminating settings, alongside ice-motion patterns which are far more complex than previously considered. I show that temperate ice is expected to be vertically extensive in deep troughs, but to thin over bedrock highs. I further show that basal-slip rates are interconnected with this variability, reaching >90% or <5% of surface velocity dependent on setting. Last, I apply the assembled model to real high-resolution bed topography data produced by radio-echo sounding at Thwaites Glacier, Antarctica. This reveals a distinct pattern of ice motion controlled by rough topographic highs where basal slip rates are highly variable, and the landscape is predominantly erosive, with broader topographic basins where basal slip is high and uniform, and the landscape is predominantly depositional. This work further suggests the existence of basal temperate ice layer beneath Thwaites Glacier, at least at the rougher topographic highs. Overall, this thesis advances understanding of how ice sheets move, which may ultimately lead to improved parameterisations of ice-sheet motion for predictive models.
Open Access
Observing the Seasonal Evolution of Supraglacial Ponds in High Mountain Asia: A Supervised Classification Approach
(2022-07) Smith, Caroline Sophia Rose
Supraglacial ponds on debris covered glaciers in High Mountain Asia (HMA) can locally store surface runoff and prolong water delivery to downstream river basins (Benn et al., 2012; Miles et al., 2019). Temporal variation in the extent of supraglacial ponding therefore affects the timing and availability of water supplies to communities downstream. Large supraglacial ponds can rapidly drain during Glacial Lake Outburst Flood (GLOF) events, which presents a hazard risk to local populations (Nie et al., 2018). Furthermore, the rate of glacier surface mass loss is locally enhanced by supraglacial ponds, so that supraglacial ponds influence the sensitive response of HMA glaciers to climate change (Sakai et al., 2000). Region-wide, multi-temporal maps of supraglacial pond cover are therefore required as inputs to glacier hydrology and mass balance models (Miles et al., 2020). Remote sensing techniques are often used for supraglacial pond mapping because of their wide spatial coverage and capacity for repeat observations. However, current approaches are limited by factors including efficiency and poor transferability throughout time and space (Watson et al., 2018; Wangchuk and Bolch, 2020). This study develops an efficient, accurate pond mapping approach that is widely spatiotemporally applicable in the HMA region. An unsupervised k-means classifier is used to train a supervised Random Forest Classifier (RFC) in the Google Earth Engine platform. This study adapts algorithms used by Dell et al., (2021) for application in the HMA region. The classifier is trained on four spatially distal glaciers within the Himalaya region, with Sentinel-2 optical satellite imagery obtained from April 2017 to October 2021 and 8m resolution HMA DEM data. The RFC is validated against manually derived pond outlines at these glaciers. The RFC achieves accuracy of 86.3-99.6% against manually derived outlines for supraglacial ponds with an area greater than 1000m2. A Root Mean Square Error of 978.4m2 is calculated across 222 overlapping pond outlines included in the validation process. The classifier is an important contribution to the existing literature because it is capable of mapping ponds with area less than <10000m2 across multiple glacier valleys and timepoints accurately and efficiently. The RFC is applied to two of the training sites, Tshojo Glacier, Bhutan Himalaya and Langtang Glacier, Nepal Himalaya, during March-October 2017-2021. This study period encompasses months designated in this study as the Pre-Monsoon (March-April), Early-Monsoon (May-June), Late-Monsoon (July-August) and Post-Monsoon (September-October) periods. At Tshojo Glacier, a seasonal pattern of pond filling during the Pre-Monsoon and Early-Monsoon and drainage in the Late-Monsoon is observed. This pattern is consistent with other literature observations and is indicative of the operation of a rapid englacial drainage mechanism triggered by increased hydraulic potential gradients between ponds throughout the monsoon season (Benn et al., 2012; Miles et al., 2017; Narama et al., 2017). At Langtang Glacier, a pattern of continual pond expansion in the central ablation zone is observed from 2018-2021. This pattern is unusual and contrasts earlier observations of seasonality at Langtang Glacier (Miles et al., 2017; Steiner et al., 2019). Supraglacial pond seasonality at Langtang Glacier therefore requires extensive further investigation through remote sensing and field observations. However, this study makes the very tentative suggestion that decreasing ice velocity in the central ablation zone may have recently caused compressional ice flow that closes relict englacial conduits, so that they are not available as drainage routes during the Late Monsoon. The findings of this study indicate that complex inter-connected climatic, hydrological and glaciological processes control the evolution of supraglacial ponds in the Himalaya region.
Open Access
Fragmentary Connections: Authorship, Curation, and Absence in Polar Scrapbooking, 1870-1920
(2021-07) Wood, Deborah
This dissertation will explore two sets of family scrapbooks held in the Scott Polar Research Institute (SPRI)’s archives, examining them as historical sources in their own right, and subsequently for the alternative narratives and experiences of polar expeditions that they offer to our historic understandings of exploration. These are unusual, heterogenous, and relatively unexplored sources; curated from a variety of press clippings, letters, images, and expedition ephemera, these volumes were made to preserve a narrative of the explorer’s life story, lived experiences, and movements by those that they left behind. I will examine these sources for the alternative perspectives of polar exploration that the family expressed through their collection, and to examine how these accounts shifted in the light of the explorer’s death. Combining frameworks from the academic literature on scrapbooking with discussions from several other disciplines, I will take an interdisciplinary approach to these sources, reading them both for their ephemera, and as a whole narrative, as individual sources, and together as representations of polar scrapbooking, in order to explore these overlooked sources for all that they are, and all that they represent. My research questions are anchored in the three themes that run throughout this dissertation. The first theme, authorship, is explored by asking whose voices are prominent or conspicuously absent within the sources in order to examine the combined effort and layers of narration that build up the scrapbook’s overarching accounts. The second, curation, examines the material culture of the scrapbooks. Through examining the most common forms of ephemera in the scrapbooks, and how each scrapbooker ordered and captioned their collections, we can gain a sense of the scrapbook’s purpose, and how this changed over time. The final theme, absence, explores the emotional histories of the scrapbooks, and how this influenced their changes in purpose. Originally curated to soothe familial anxieties during their loved one’s precarious absences, I ask how the news of their deaths altered the sources’ collections and purposes as their creator scrambled to preserve a cohesive memory of their loved ones. My primary research has been impacted by the ongoing restrictions necessitated by the Covid-19 pandemic. Although my scope was limited to two sets of scrapbooks, my sources have revealed a number of valuable conclusions when read together; and the sheer variety within the scrapbooks in the SPRI archives create an interesting scope for further study. The two sources in question are markedly different in format, with the six large scrapbooks detailing Lieutenant Wyatt Rawson’s naval and exploratory career standing far larger in scope and scale than the single volume narrating the Antarctic experiences of Victor (‘Vic’) Hayward. These unique sets of sources offer valuable, alternative narratives of the experiences of polar exploration. I hope to show how these narratives can expand and enhance our understandings of historic polar exploration to account for the long-lasting impacts that these expeditions had on those that the explorers left behind.