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Zayed, Ahmed Abdelfattah. "Microbe-Environment Interactions in Arctic and Subarctic Systems." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1562494472055278.
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Nyström, Jesper. "Predator-prey interactions of raptors in an arctic environment." Doctoral thesis, Stockholm University, Department of Zoology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-259.
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<p>This thesis concerns the predator-prey interactions of three raptor species in a Swedish arctic community: the gyrfalcon (<i>Falco rusticolus</i>), the rough-legged buzzard (<i>Buteo lagopus</i>) and the golden eagle (<i>Aquila chrysaetos</i>).</p><p>The gyrfalcon behaved like a highly specialised ptarmigan (<i>Lagopus spp.</i>) predator. Gyrfalcon’s functional response to ptarmigan was close to density independent, and ptarmigan remained the dominating prey even in areas with the lowest ptarmigan density. The gyrfalcon did not respond functionally to microtine rodents (i.e. lemmings and voles) and it was clear that the gyrfalcon did not use microtines as an alternative prey category to ptarmigan. As the gyrfalcons did not switch to any alternative prey when ptarmigan was scarce, their reproductive success seemed to be directly dependent on the amount of ptarmigan available in the breeding territories. Of the two ptarmigan species in the study area, rock ptarmigan (<i>L. mutus</i>) dominated gyrfalcon’s diet. Locally, the proportion of rock ptarmigan in gyrfalcons’ diets showed a positive relationship to the expected availability of rock ptarmigan in the breeding territories, indicating a density dependent utilisation. </p><p>The rough-legged buzzard behaved like a highly specialised microtine rodent predator and Norwegian lemming (<i>Lemmus lemmus</i>) was its preferred microtine species. The buzzards showed a type 2 functional response to lemmings. Surprisingly though, they also had a type 3 functional response to grey-sided voles (<i>Clethrionomus rufocanus</i>). We present an optimal diet model where a central place forager, during good food conditions, benefits from partial prey preference, which renders separate functional responses to each prey category. We discuss how the double functional responses of the buzzard affect the population dynamics of sympatric vole species, on both temporal and spatial scales.</p><p>The golden eagle behaved like a generalist predator, and it preyed on all major prey categories in the study area: microtines, ptarmigan, mountain hare, (<i>Lepus timidus</i>) and reindeer (<i>Rangifer tarandus</i>). It seemed to respond functionally to microtine rodent fluctuations with an increased consumption of lemmings during a peak year in the microtine rodent cycle. The golden eagle showed a numerical response to its main prey, the ptarmigan. </p><p>Ptarmigan, microtine rodents and hares seemed to have synchronized population fluctuations in the study area. Such synchronized population fluctuations are believed to be generated by predation. Although the three raptors are the main predators of their community, their predation patterns fail to explain the observed prey population dynamics in the study area. </p>
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Brooker, Robin William. "Plant-plant and plant-environment interactions in the Arctic." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301266.
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Bolstad, Scott H. "Hydrodynamic response of a composite structure in an Arctic environment." Thesis, Monterey, California: Naval Postgraduate School, 2015. http://hdl.handle.net/10945/45817.
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Approved for public release; distribution is unlimited<br>Climate change has resulted in an increase in naval activity in the Arctic Ocean. While extensive research has been done on the interaction between different forms of ice and conventional steel hulls, little work has been done to assess the potential for composite-hulled vessels to operate safely in Arctic sea lanes. The goal of this experiment was to determine how well a composite hull can withstand ice loading and impacts with free-floating ice and whether a tumblehome, conventional, or a vertical hull performs best in the presence of ice. In order to do this, the tow tank at the Naval Postgraduate School was used. An ice equivalent was found which allowed for repeatable experimentation. Strain gauges were attached to critical locations of the composite plate towed through the tank. Both plate deformation and the resulting hydrodynamic force were measured for various ice conditions. A high-speed camera was used to qualitatively understand the flow characteristics of the ice around the composite plate. Finally, Ansys was used to determine if it was possible to replicate the experimental results. This work lays a basis for future tow tank experimentation involving ice interaction at the Naval Postgraduate School.
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Camus, Lionel Andre Yves. "Biomarkers relevant to oil and gas industrial activities in low temperature marine ecosystems." Thesis, University of Plymouth, 2001. http://hdl.handle.net/10026.1/1080.
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Because of its geographical location, the Arctic environment is considered as pristine. However, expanding industrial activities in the Arctic require assessment of the toxicity of chemicals at low temperature. Biomarkers defined as "biological responses to a chemical or chemicals that give a measure of exposure or toxic effect" were shown to be relevant to measure in situ impact of oil discharges. Most biomarker studies have been performed with temperate organisms. The Arctic is characterised by low stable temperature, strong seasonality in light, resulting in a short primary production in Spring. Therefore, indigenous organisms have developed specific adaptations to live with a hmited food supply in water near freezing point. Conversely, physical properties of petroleum hydrocarbons are affected by low temperature (i.e. reduced solubility). Consequently, the biological adaptation of cold-water organisms together with the altered oil behaviour, may affect typical biomarker responses. Because oil compounds are strongly prooxidant, the research strategy of this work was based on oxidative stress. The antioxidant defences were investigated by measuring the total oxyradical scavenging capacity (TOSC). The impact of reactive oxygen species was investigated by measuring the stability of the cell membranes. Finally, the physiology of the organisms was considered by looking at heart and respiration rates. Invertebrates were selected for study owing to their abundance in the polar ecosystem. They were sampled using dredges and Scuba diving from the research vessel Jan Mayen (University of Tromso) in May and August 1999, and during May and September 2000 in the l^ords of Svalbard and in Antarctica as well in January 2000. In the Arctic, two bivalves, Mya tnincata and Chlamys islandicus, and two crustaceans, Hyas araneus and Sclerocrangon boreas were selected. In this work, the ecophysiology of Arctic and Antarctic marine invertebrates was investigated and compared to temperate organisms. Polar marine invertebrates are characterised by low respiration and heart rates and a high TOSC. The elevated level of antioxidant defences is thought to reflect the oxidative pressure of the polar marine ecosystem; however, it suggested that a high TOSC may help to protect biomolecules from oxidative damage as repair mechanisms are limited due to the lack of food for 9 months. Organisms were exposed to poly aromatic hydrocarbons either dissolved, dispersed injected or via sediment. TOSC, cell membrane stabiHty and heart rate were valid biomarkers to monitor the impact of poly aromatic hydrocarbons in Arctic marine organisms. The biomarker responses obtained in this study provide essential background information for monitoring the potential impact of oil and gas activities in the Arctic.
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Howe, Thomas (Thomas Ryan). "A modal analysis of acoustic propagation in the changing Arctic environment." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101542.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (page 59).<br>This work takes an in depth look at acoustic propagation through double duct sound speed profiles in the Arctic. While the traditional Arctic sound speed profile has a single surface duct, some portions of the Arctic have a sound speed profile which includes a second, lower duct. These double duct systems are seen through out the Beaufort Sea, dating back to 2004, in data made available by the Ice-Tethered Profiler program at the Woods Hole Oceanographic Institutes. The acoustic propagation through the double duct system is analyzed using normal mode analysis, through the Kraken normal mode code. A simulated lower duct is introduced in order to isolate only those modes which travel within the lower duct. Propagation through the lower duct is compared to propagation in traditional Arctic sound speed profiles, and for certain ducts distinct increases in propagation strength are shown.<br>by Thomas Howe.<br>S.M.
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Wurtele, A. Bruce. "Natural disturbance and land cover patterns in a mountainous, sub-Arctic environment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0027/MQ52227.pdf.
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Shannon, Kerrie Ann. "Readiness and skill in an arctic environment : procurement, distribution and game playing." Thesis, University of Aberdeen, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401181.
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In this dissertation I provide an ethnographic account of life in Coral Harbour, a predominantly Inuit community in Nunavut, Canada. I specifically address aspects of procurement and everyday life that have often been under-represented in other Canadian Arctic ethnographies. Whereas Arctic research commonly emphasises the importance of hunting as a major procurement activity, I focus specifically on other procurement activities that are separate from hunting. Through an examination of women’s, children’s, and men’s activities in procurement, I address a lacuna in the literature and provide insight into how Inuit in Coral Harbour engage in procurement activities. I specifically explore the interrelated activities of procurement, sharing, and game playing. My intention is to provide a balanced ethnographic account of life in Coral Harbour and to utilize this ethnographic material in order to explore anthropological understandings of Inuit and hunter-gatherers more generally. I provide detailed examinations of fishing and fishing derbies as a procurement activity in which women, children, and men all participate. Mobility, readiness, and opportunism are shown to be important aspects of procurement. I suggest that Inuit in Coral Harbour engage in procurement activities by maintaining a state of readiness. Inuit in Coral Harbour have awareness and skill, and are ready to seize an opportunity when it presents itself. As a consequence of understanding procurement as opportunistic, I examine the notion of the ‘giving environment’. I explore how Inuit share, transfer, and exchange a variety of resources within the community. Games provide a mechanism for distribution within the entire community, based upon egalitarian principles. By examining game playing within an Inuit cultural context, I show how it relates to both procurement and distribution. Many contests involve some type of procurement activity, such as the fishing derby. Skill and readiness to seize an opportunity are important both in games and in activities of livelihood.
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Gydemo, Östbom Viktor. "Lake water chemistry and the changing arctic environment : Topographic or climatic control?" Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-155903.
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The arctic is expected to be one of the regions most affected by ongoing climate change, with relative changes in air temperatures significantly higher than the global mean. Lakes are recognized for their potential role in the global climate system and as ecosystems of importance for local societies. As such, there is a scientific interest regarding how arctic lakes and their geochemistry will respond to climatic changes. Lakes around Kangerlussuaq (66.99 N, 51.07 W), south-west Greenland, are known for their unique geochemical composition, including oligosaline lakes, of which some are enriched in colourless dissolved organic carbon (DOC). The origin of this DOC and the importance of local catchment properties for the general water chemistry is currently being debated. This thesis aimed at: i) exploring the extent and effect of catchment morphology on lake-water chemistry in the Kangerlussuaq area; ii) determine the predominant origin of DOC, aquatic or terrestrial. I used a remote-sensing approach based on satellite imagery and digital elevation model (DEM) in deciding landscape influence on water chemistry (pH, alkalinity, conductivity, base cations, sulphate, nitrogen and absorbance). To trace the origin of the organic sources behind DOC lake water and sediments, I used a hydrogen isotope tracing method. The remote sensing approach revealed that morphological characteristics serving as proxies for lake water residence time and hydrologic connectivity (e.g. lake altitude difference and absence of outlets) explained up to 77% of the variations in lake water chemistry. The hydrogen isotopic signature of the DOC indicated a predominantly autochthonous origin, i.e. 59 to 78% was estimated to originate from algae. I conclude that lake water chemistry of the lakes in the study area is primarily controlled by the precipitation : evaporation balance, enhanced by static catchment characteristics regulating water age. Thus, the examined lake water chemical properties are likely to remain across future climatic scenarios, providing the current precipitation : evaporation balance prevails.
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Hjalmarsson, Julia. "PIA as an Instrument for Work Environment Management at Arctic Paper Grycksbo." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70470.
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This thesis describes the work of investigating and developing Arctic Paper Grycksbo’s work environment work, focusing on their use of the Paper industry’s information system on work environment (Pappersindustrins Informationssystem om Arbetsmiljö, PIA). The work took place between January and June 2018 as a final part of the Master Programme in Industrial Design Engineering at Luleå University of Technology. The client of the project was Arctic Paper Grycksbo, one of three paper mills in the Arctic Paper Group. The work began with a literature study where areas such as production design, safety, work environment management, risk analysis, etc. was covered. Subsequently, a comprehensive survey of the PIA system was conducted in parallel with a survey of the company’s overall work environment management. This resulted in a clear picture of how the system is used, the role of the system in the work environment management and where there were shortcomings in the work being done today. An identified deficiency was that the quality of investigations of the reported events varied a lot depending on who performed the investigation, another identified deficiency was that there were a number of delayed events that appeared to be investigated and corrected but wasn’t marked as done in the system. To investigate how other companies use the system, a benchmarking was conducted where companies using any variant of the system got to answer how they use the system and what they like about the system. Based on the investigation of the system, Arctic Paper Grycksbo’s use of the system and the use of the benchmarked companies, six areas for improvement was identified, such as the uneven quality of investigation, the delayed events, their use of the risk management module and their analysing of the information in the system. When the areas of improvement were identified, the work was continued to develop how they could improve their use of PIA. First, six of the former benchmarked companies were contacted for more detailed interviews about how they use the system. Based on the deeper benchmarking, the theoretical framework and the areas where Arctic Paper Grycksbo can improve, new routines for Arctic Paper Grycksbo’s use of PIA was developed. As part of the routines, recommendations and instructions for statistics were also developed that they should begin to follow in the system. Arctic Paper Grycksbo is recommended to start following eight safety indicators, three leading and five lagging, and seven trends regarding the characteristics of accidents and incidents. The possibilities in the system are huge and there is a great potential to use it for most parts of the work environment work if you only set the time from the beginning and are aware that it requires some active work.<br>Det här examensarbetet beskriver arbetet med att undersöka och utveckla Arctic Paper Grycksbos arbetsmiljöarbete med fokus på deras användning av Pappersindustrins Informationssystem om Arbetsmiljö (PIA). Arbetet pågick mellan januari och juni 2018 som en avslutande del på civilingenjörsprogrammet Teknisk Design på Luleå Tekniska Universitet. Uppdragsgivare var Arctic Paper Grycksbo, ett av tre pappersbruk i Arctic Paper koncernen. Arbetet inleddes med en litteraturstudie där områden som produktionsdesign, säkerhet, arbetsmiljöarbete, riskanalys, m.m. behandlades. Därefter genomfördes en omfattande undersökning av PIA-systemet parallellt med en undersökning av företagets övergripande arbetsmiljöarbete. Detta resulterade i en tydlig bild av hur systemet används, systemets roll i arbetsmiljöarbetet och var det fanns brister i arbetet som görs idag. En brist som identifierades var att kvaliteten på utredningarna av de rapporterade händelserna varierade mycket beroende på vem som utfört utredningen, en annan brist som identifierades var att det fanns ett flertal förfallna händelser som såg ut att vara utredda och åtgärdade men saknade klarmarkering i systemet. För att undersöka hur andra företag använder systemet gjordes en benchmarking där företag som använder någon variant av systemet fick svara på hur de använder systemet och vad de tycker om systemet. Baserat på undersökningen av systemet, Arctic Paper Grycksbos användning av systemet och de benchmarkade företagens användning av systemet identifierades sex områden där de kan förbättra och utveckla sin användning av systemet, så som den ojämna kvaliteten på utredningarna, de förfallna händelserna, deras användning av riskhanteringsmodulen och deras användning av informationn i systemet. När förbättringsmöjligheterna var identifierade fortsatte arbetet med att utveckla hur de kan förbättra sig. Först så kontaktades sex av de tidigare benchmarkade företagen för mer detaljerade intervjuer av hur de använder systemet. Utifrån den djupare benchmarkingen, den teoretiska referensramen och de områden där Arctic Paper Grycksbo kan förbättra sig, utvecklades nya rutiner för användningen av PIA. Som en del av rutinerna utvecklades även rekommendationer och instruktioner för statistik de bör börja följa i systemet. Arctic Paper Grycksbo rekommenderas börja följa åtta säkerhetsindikatorer, tre ledande och fem eftersläpande, och sju trender gällande olyckornas och tillbudens egenskaper. Möjligheterna i systemet är enorma och det finns stor potential att nyttja det till de flesta delar av arbetsmiljöarbetet om man bara lägger tiden på det från början och är medveten om att det kräver visst aktivt arbete.
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Kaparulina, E. (Ekaterina). "Eurasian Arctic ice sheets in transitions:consequences for climate, environment and ocean circulation." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526217765.
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Abstract In this Ph.D. thesis sediment cores from the central Arctic Ocean, southwestern Barents Sea and sediment exposures from the Kola Peninsula were investigated in order to reveal interactions between the late middle Pleistocene and late Pleistocene Arctic ice sheets, between Marine Isotope Stages 6 and 1 (MIS 6 and MIS 1). One of the main objectives of this work is to establish provenance areas for the sediments studied in the central Arctic, the southwestern (SW) Barents Sea and the Kola Peninsula, their transport mechanisms and through that their relationship to glaciations in the Arctic and to development in the Kola Peninsula during the late middle and late Pleistocene. Mineralogical and geochemical data from the core 96/12-1pc on the Lomonosov Ridge, central Arctic Ocean was studied to evaluate ice transport from circum-Arctic ice sheets and variability in sediment drainage systems associated with their decay. SW Barents Sea sediments contain important information on Late Glacial and Holocene sediment provenance characteristics in relation to ice flow patterns and ice rafting from different regional sectors. The studied SW Barents Sea sediment cores show that sediments were most likely derived from a combination of far-field Fennoscandian sources, local subcropping Mesozoic strata below the seafloor and sea ice transport. The investigation carried out on the Kola Peninsula indicates that the Eemian (MIS 5e) marine environment in the White Sea Basin and onshore coastal areas gradually changed into a glaciolacustrine environment during MIS 5d to MIS 5a. Subsequently, the Scandinavian Ice Sheet (SIS) covered the Kola Peninsula, most probably during MIS 4. The final deglaciation of the SIS on the Kola Peninsula took place, however, during the late Weichselian (MIS 2) between 16–12 ka<br>Tiivistelmä Tässä väitöstutkimuksessa tutkittiin sedimenttikairanäytteitä keskeiseltä Jäämereltä ja Lounais-Barentsinmereltä sekä tarkasteltiin sedimenttiseurantoja Kuolan niemimaalla tarkoituksena selvittää myöhäisen keskipleistoseeni- ja myöhäispleistoseeniajan Arktisten jääkenttien keskinäiset vuorovaikutukset erityisesti merellisten isotooppivaiheiden 6 ja 1 (MIS 6 ja MIS 1) välillä. Tämän työn yhtenä päätavoitteena on määritellä sedimenttien lähdealueet keskeisellä Arktiksella, lounaisella Barentsinmerellä ja Kuolan niemimaalla, sedimenttien kuljetusmekanismit ja näiden perusteella riippuvuudet Arktisiin jäätiköihin ja Kuolan niemimaalla tapahtuneeseen myöhäiskeski- ja myöhäispleistoseenin kehitykseen. Mineraloginen ja geokemiallinen tieto Lomonosovin harjanteen kairauksesta 96/12-1pc, keskeisellä Jäämerellä on perusta arvioitaessa jääkuljetusmekanismeja ympäröiviltä sirkum-Arktisilta jäätiköiltä ja arvioitaessa valuma-alueiden osuutta suhteessa näiden jäätiköiden häviämiseen. Lounaisen Barentsinmeren sedimentit sisältävät tärkeätä tietoja viimeisen jäätiköitymisen loppuvaiheen ja holoseeni-ajan sedimenttien lähdealueista ja suhteista jäävirtauksiin ja jääkuljetukseen eri aluesektoreilta. Tutkitut Lounais-Barentsinmeren sedimentit osoittavat, että sedimentit olivat todennäköisimmin peräisin suhteellisen kaukaisilta Fennoscandian lähdealueilta, paikallisista mesotsoosista merenpohjan kerrostumista ja merijään kuljettamasta materiaalista. Kuolan niemimaalla tehty tutkimus osoittaa, että Eem-kauden (MIS 5e) meriympäristö Vienanmeren altaassa ja rannikkoalueilla vähitellen muuttui glaciolakustriseksi ympäristöksi MIS 5d:n ja MIS 5a:n välisenä aikana. Sen jälkeen Skandinavian jääkenttä (SIS) peitti Kuolan niemimaan, todennäköisimmin koko MIS:n 4 ajanjakson. SIS:n lopullinen deglasiaatio alkoi Kuolan niemimaalla kuitenkin myöhäisen Veiksel-jääkauden (MIS 2) aikana noin 16–12 ka sitten
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Pucko, Monika. "The effect of atmosphere-snow-ice-ocean coupling on hexachlorocyclohexane (HCH) pathways within the Arctic marine environment." CMOS, 2010. http://hdl.handle.net/1993/4767.
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The importance of the cryosphere, and of sea ice in particular, for contaminant transport and redistribution in the Arctic was pointed out in the literature. However, studies on contaminants in sea ice are scarce, and entirely neglect the sea ice geophysical and thermodynamic characteristics as well as interactions between various cryospheric compartments. This thesis addresses those gaps. Ice formation was shown to have a significant concentrating impact on the levels of HCHs in the water just beneath the ice. Both geophysical and thermodynamic conditions in sea ice were shown to be crucial in understanding pathways of accumulation or rejection of HCHs. Although HCH burden in the majority of the ice column remains locked throughout most of the season until the early spring, upward migration of brine from the ice to the snow in the winter has an effect on levels of HCHs in the snow by up to 50 %. In the spring, when snow melt water percolates into the ice delivering HCHs to the upper ocean via desalination by flushing, levels of HCHs in the ice can increase by up to 2 %-18 % and 4 %-32 % for α- and γ-HCH, respectively. Brine contained within sea ice currently exhibits the highest HCH concentrations in any abiotic Arctic environment, exceeding under-ice water concentrations by a factor of 3 in the spring. This circumstance suggests that the brine ecosystem has been, and continues to be, the most exposed to HCHs. α-HCH levels were shown to decrease rapidly in the last two decades in the Polar Mixed Layer (PML) and the Pacific Mode Layer (PL) of the Beaufort Sea due to degradation. If the rate of degradation does not change in the near future, the majority of α-HCH could be eliminated from the Beaufort Sea by 2020, with concentrations in 2040 dropping to < 0.006 ng/L and < 0.004 ng/L in the PML and the PL, respectively. Elimination of α-HCH from sea water takes significantly longer than from the atmosphere, with a lag of approximately two decades.
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Savishinsky, Joel S. "The trail of the hare : environment and stress in a sub-arctic community /." Yverdon (Switzerland) : Gordon and Breach, 1994. http://catalogue.bnf.fr/ark:/12148/cb37463831g.
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Shapovalova, Daria. "The effectiveness of the international environmental legal framework in protecting the Arctic environment in light of offshore oil and gas development." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=236459.
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Urban, Marcel [Verfasser], Christiane [Akademischer Betreuer] Schmullius, and Martin [Akademischer Betreuer] Herold. "Multi-scale earth observatin of the arctic environment : a pan-arctic climate and trend analysis for the last decades / Marcel Urban. Gutachter: Christiane Schmullius ; Martin Herold." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2015. http://d-nb.info/1067098623/34.
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Pizzolato, Larissa Anna Vincenza. "Arctic Shipping in Canada: Analysis of Sea Ice, Shipping, and Vessel Track Reconstruction." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33156.
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Declining sea ice area in the Canadian Arctic has gained significant attention with respect to the prospect of increased shipping activities along the Northwest Passage and Arctic Bridge shipping routes. Temporal trend and correlation analysis was performed on sea ice area data for total, first-year ice (FYI), and multi-year ice (MYI), and observed shipping activity within the Vessel Traffic Reporting Arctic Canada Traffic Zone (NORDREG zone) from 1990 to 2012. Relationships between declines in sea ice area and Arctic maritime activity were investigated alongside linkages to warming surface air temperatures (SAT) and an increasing melt season length. Statistically significant increases in vessel traffic were observed on monthly and annual time-scales, coincident with declines in sea ice area. Despite increasing trends, only weak correlations between the variables were identified, suggesting that other non-environmental factors have likely contributed to the observed increase in Arctic shipping activity including tourism demand, community re-supply needs, and resource exploration trends.
As a first step towards quantifying spatial variability in shipping patterns, a case study was conducted using 2010 observed shipping data to reconstruct historical shipping routes using a least cost path (LCP) approach. This approach was able to successfully reconstruct vessel tracks compared to an independent data source (Automatic Identification System) to an accuracy of 10.42 km ± 0.67 km over the entire study area. A 25 km gridded product across the entire Canadian Arctic domain was produced for 2010, with this approach now providing a basis to apply this method over the entire record (since 1990) in future studies to investigate long term spatial variability and change of shipping activity across the Canadian Arctic.
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Amiraux, Rémi. "Ice biota degradation in the Arctic environment : impact of bacterial stress state on this material's preservation and burial." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0189/document.
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L’océan Arctique, particulièrement sensible au changement climatique, a vu lors des dernières décennies une augmentation de sa température deux fois supérieure à la moyenne mondiale. Certains scientifiques prévoient la disparition complète de la banquise pour 2050. Du fait de la future disparition des algues de glace et de l’augmentation de la fonte du pergélisol, une réévaluation de leurs contributions respectives au stockage de CO2 est nécessaire. Dans cette étude, nous avons ainsi montré que les algues de glace possèdent une forte capacité de préservation dans les sédiments (et donc de stockage du CO2) due à l’incapacité de leurs bactéries à les reminéraliser. A l’inverse, les quantités grandissantes de pergélisol rejetées en mer sont fortement reminéralisables. L’effet conjoint de l’augmentation du rejet de CO2 lors de la dégradation du pergélisol et de la diminution de son stockage par les algues de glace devrait donc contribuer à une amplification du réchauffement climatique<br>With a rise in Arctic temperatures almost twice as large as the global average in recent decades, it is at high latitude that the effects of global warming are the most evident. Thus, some scientists have already predicted the complete disappearance of sea ice for 2050. Due to the future disappearance of ice algae and the increase of permafrost thawing, a reassessment of their respective contributions to CO2 storage was required. We have shown that unlike permafrost, ice algae are highly preserved in sediments (allowing CO2 storage) due to the inability of their bacteria to remineralize them. The combined effect of increasing discharge of permafrost by Arctic rivers and decreasing storage of ice algae due to the disappearance of sea ice should thus contribute to increase the global warming
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Strand, Ida. "What does the Increased Fossil Fuel Scarcity mean for the Arctic Region? A Quantitative and Qualitative Content Analysis of Canada, Denmark, Norway, the United States and Russia's Arctic Strategy." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-21199.
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This bachelor thesis asks the question, what does the increased fossil fuel scarcity mean for the Arctic region? It further investigates the aim and motives by the five main Arctic states. With the use of structural realism, existing research on the parallels between resource scarcity and conflict and, the combination of two methodological approaches: quantitative and qualitative content analysis, I argue in this study that the five states will act in accordance with the structural realist way and exploit the Arctic due to the protection of their national interests and security. This thesis highlights that, firstly, there is a process of climate change enabling the accessibility to extracting fossil fuel. Secondly, there is an ongoing militarization of the region. With that being said, I argue that the race for fossil fuel will prevail and this will create a destabilizing Arctic region with environmental impacts and militarization that can lead to problematic disputes and even conflicts. Therefore, the Arctic is a vulnerable region with a questionable future due to its economic stakes and militarization.
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Parker, Thomas C. "Ecological controls of rhizosphere processes and soil organic matter dynamics at a Sub-Arctic treeline." Thesis, University of Stirling, 2015. http://hdl.handle.net/1893/22369.
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Rapid climate change in the Arctic and Sub-Arctic is causing vegetation change across large areas of tundra. Shrubs and trees are undergoing range expansions as part of an over-all trend of ‘greening’ of the tundra. This is of importance because northern peatlands contain around half of total soil carbon (C) and there is a potential for productive vegetation to interact with this C in a number of ways: (1) Ectomycorrhizal fungi (ECM) in symbiosis with trees and shrubs could potentially stimulate decomposition through extracellular enzyme production whilst extracting nitrogen (N) for their hosts; (2) deep snow, trapped by tall vegetation insulates the soil, resulting in higher winter-time microbial activity and has potential to influence growing season microbial activity; (3) the biochemistry of litter and decomposition environment associated with more productive vegetation could result in accelerated mass loss of litter and stimulate decomposition of older soil C. This thesis investigates how productive sub-arctic plant species in Northern Sweden interact with soil C by using ‘space-for-time’ transitions from forests (Betula pubescens), through intermediate shrub vegetation (Betula, Salix), to tundra heath (Empetrum nigrum). This was to test how ECM fungi, winter snow accumulation, defoliation events and litter input influence C cycling. C stocks, respiration rates and ECM growth rates were measured across these ecotones. It was found that birch forests and shrub stands had significantly lower soil C storage and higher respiration rates than adjacent heaths. This is contrary to the predictions of earth system models. Higher ECM growth rates at plots with low C storage and high cycling rates implied that they had an important role in the stimulation of C decomposition. To test whether snow cover in forests over winter had an important effect on C cycling, soils were transplanted between forest and heath (different snow cover), and respiration rates were measured over summer. It was found that deep snow cover over winter increases microbial activity in summer due to a warmer, more stable winter environment; this is hypothesised to be due to the environmental selection of a more active assemblage of decomposing microbes. A defoliation event of part of the birch forest by caterpillars allowed for a natural ‘experiment’. Trees with different degrees of defoliation were compared in their influence over soil C cycling processes. Defoliated plots shifted to slower-cycling states through a shift in the ECM community. This further implied that ECM fungi have an important role to play in rapid cycling of C in forests. A decomposition experiment using the litter of significant plant species in forest, shrub and heath communities was carried out by transplanting them between these key environments. This work showed that rapid decomposition of litter in the forest is driven by an interaction between carbohydrate-rich litter input and an effective decomposer community. This work addresses the relationship between vegetation productivity and C storage in the soil. This theme runs through every experiment as they test specific interactions between different plant groups and the soil. The results from this thesis suggest that increasing productivity and shrub expansion in the Arctic will stimulate decomposition of soil C via a number of pathways. Plant-soil interactions are clearly of importance in determining the fate of C in ecosystems and will play a key part in the balance of C in the future.
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Van, Ham Laura. "Natural recovery of human induced disturbance in an alpine/arctic tundra environment and recommendations for reclamation, Plateau Mountain Ecological Reserve." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0003/MQ42309.pdf.
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Niemi, Oskar. "De tre Arktis : en studie av Sveriges geopolitiska syn på Arktis ur kritiskt perspektiv." Thesis, Försvarshögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-5398.
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This essay explores the Swedish state’s geopolitical view and creation, of the spatial spaces in and of the Arctic. With a critical geopolitical framework, a discourse analysis is conducted on the Swedish strategy for the arctic region, with the ambition to unfold the underlining spatial spaces, actors and dramas that this discourse creates. The result of this analysis shows that Sweden creates three different Arctic spaces within its geopolitical discourse; a Swedish Arctic, a Nearby Arctic and a Regional Arctic. This has major political consequences, which will be illuminated in the essay. Perhaps the most noteworthy being the ulterior theoretical view of the Swedish state regarding the environment and the relationship between the global space and the Regional Arctic, in relation to the threat of global and regional environmental deterioration.
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Svahn, Joacim. "Metal release and mobility in an arctic lake due to artificial drainage : Effects of mining and sulfide oxidation." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-58306.
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The aim of this report was to investigate the potential effects of sulfide oxidation in sediments of an arctic lake, N Luossajärvi, induced by lowered water level. Lake water, potentially contaminated by metals, was pumped into a mine tailings impoundment. The water quality in the receiving water was evaluated to see if the drainage have had an effect on the water quality. Six sediment profiles were sampled. Each profile were divided into 5 cm sections and analyzed for major elements and trace metals. Water chemistry were analyzed at six sites. As, Ni and Cu had high concentrations within undrained sediments, where As levels were classified as highly contaminated (> 27 mg kg-1 dw). Trace metals had strong statistical correlation to each other indicating a common source. The PCA analyzes performed suggests that trace metals are controlled by a common factor and drained sediments showed two additional factors controlling the variance of metals. Water chemistry had overall good status, but As, Cd, Ni and Cu exceeded natural background values. Historical data on the other hand showed no statistical difference from measured values. No effects on water quality could therefore be seen after draining of the lake, proposing high precipitation of metals within the tailing or that metals is still prevailing in the drained sediments. Metal mobility were seen within the drained sediments, where only As and Cd were presumed connected to chemical weathering and where erosion and soil properties seems to be responsible for most metal mobility.
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McKenney, Robyn Sullivan. "The effects of sustained, individualized technology professional development with a classroom teacher on the acquisition of content and technology skills of third grade students engaged in a multi-disciplinary study of the Arctic /." Online thesis, 2004. http://www.geocities.com/bobbyn18/FINALEDITION.doc.
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Thesis (M.S.)--Eastern Connecticut State University, 2004.<br>Website for materials: http://www.geocities.com/bobbyn18/Thesis.html?1074876403923 (viewed 12-29-2005). Bibliography: leaves 93-97. Thesis also available via the World Wide Web.
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Assefa Hassen, Yohannes. "The Impacts of Mining on Arctic Environment and Society from Corporate Social Responsibility and Sustainable Development Perspectives : The Case of Jokkmokk (Kallak) Iron Mines in Northern Sweden." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-130518.
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Extractive industry in Arctic is controversial due to the ecosystems and communities in the region are highly sensitive to natural and anthropogenic disturbances as it is one of the world’s global change hot-spots, as well as its uniqueness and distinctive social and ecological significance. As mining industry has developed into sophisticated operations, yet the basic causes of environmental pollution and degradation and impacts on the natural environment of the Arctic region remain unchanged. Mining in this environment may be faced with dilemmas as the result of adverse impacts they may cause and their escalating environmental footprints; as well as reactions from pressure groups and indigenous peoples, which in turn may have a detrimental effect on their reputations and financial performances. This may further have social, environmental and political risks in their present and future roles and operations. Thus, the mining industry ought to recognize the impacts in their operations, and are required to work towards minimizing the adverse impacts and maximizing the substantial benefits of their actions on the environment, the community and local people. Corporate social responsibility (CSR) and sustainability are supposed to be two of several principles used to examine the social and environmental endeavours and results of business activity. The aim of this thesis is to assess the environmental and social impacts associated with major mining operations Arctic region, and to conduct preliminary review of the perspectives of CSR and sustainable development in countries across the Arctic region and subarctic, especially the United States of America (USA), Finland and Sweden. As well as conduct comparative study and analysis on how corporate entities in these countries dealing with the two theoretical frameworks and how they are approached in practice and managed, and information are disclosed. The study also concentrates on how these issues can be handled in the case of Jokkmokk (Kallak) Iron Mines in Sweden. Different methodological approaches and techniques have been adopted in this study. The literature review is supplemented by interviews with strategically important stakeholders. The Environmental Impact Assessment (EIA) statement is reviewed and conceptual modeling is also employed to demonstrate the dynamic effects and consequences of the Kallak North Iron Mines. The findings in this thesis propose that the corporations’ in the USA show differences from those of the European countries in defining and addressing social and environmental concerns; as well as managing CSR and sustainability issues and communicating them as there are qualitatively different practices and approaches to CSR in these countries. In conclusion, main points are suggested as important recommendations entailing of some clear expectations to fulfill on how CSR and sustainability issues may be handled by extractive industry including the case of Jokkmokk (Kallak North) Iron Mines.
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Ullmann, Tobias [Verfasser], Roland [Gutachter] Baumhauer, Stefan [Gutachter] Dech, and Hans-Wolfgang [Gutachter] Hubberten. "Characterization of Arctic Environment by Means of Polarimetric Synthetic Aperture Radar (PolSAR) Data and Digital Elevation Models (DEM) / Tobias Ullmann. Gutachter: Roland Baumhauer ; Stefan Dech ; Hans-Wolfgang Hubberten." Würzburg : Universität Würzburg, 2015. http://d-nb.info/111178387X/34.
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Idiens, Melissa Clare. "Gateway Antarctica: A Route for the EU's Global Political Agenda." Thesis, University of Canterbury. National Centre for Research on Europe, 2012. http://hdl.handle.net/10092/8361.
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This thesis endeavours to address an identified gap in literature on the European Union’s (EU) scientific and political engagement in the Antarctic Treaty System (ATS). The examination of this engagement begins from the initiation of the EU’s formal participation in the ATS in 1983 as a Party to the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR) mechanism, through to the EU’s contemporary role in 2011, for the facilitation of European collaborative scientific research on the Antarctic continent that remains under negotiation pending decisions on funding allocations for polar research under the EU Commission’s Horizon 2020 Framework Programme for Research and Innovation (2014-2020).
Particular focus is placed on analysis into the EU’s role in global environmental discourse, for contextualised examination on the hypothesis of this research, which posits that the EU could upgrade its role in the Antarctic to further legitimise a strategic agenda for recognition as a global political actor in international relations. As most of the EU’s participation in the process of Antarctic political deliberation was afforded as an observer to the series of Special Antarctic Treaty Consultative Meetings (SATCM XI-1 to XI-IV) which developed the Protocol on Environmental Protection to the Antarctic Treaty (1991), a significant amount of analysis will focus on EU and Member State involvement in the development of this Protocol. There is also a supplementary exploration of Europeanisation of French foreign policy over this period.
In addition to contributing to the academic literature, recommendations concerning the future of the EU’s scientific and political Antarctic engagement could be used as informative and topical research for a mixed audience of European Union (EU) strategists, policy-makers and officials who are tasked with furthering the development of the EU into a global political actor. It could also be of interest to those people in the Antarctic community who might opportunistically seek to maximise the benefits of an increase in direct and indirect EU participation in the Antarctic, particularly the availability of EU funding for Antarctic scientific research.
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ADER, MARIA, and DAVID AXELSSON. "Drones in arctic environments." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-217918.
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This is a master thesis by Maria Ader and David Axelsson, students at the Master of Science in Engineering degree program in Design and Product Realization at KTH, within the master program Integrated Product Design. The thesis work will benefit ÅF and the EU project ɪɴᴛᴇʀᴀᴄᴛ. The ɪɴᴛᴇʀᴀᴄᴛ project is part of the EU’s effort to forward climate research, and aims to “coordinate and harmonize research and monitoring efforts that will greatly contribute to our knowledge and understanding of changes occurring in the arctic environment.” One out of 12 subprojects within ɪɴᴛᴇʀᴀᴄᴛ aims to “increase awareness of drone technology and sensors among researchers and research station managers while making industry aware of innovative potential uses requiring drone and sensor development.” A drone is an unmanned aerial system/vehicle (UAS/UAV), i.e. an airborne vehicle without a human pilot aboard. This master thesis examines the need of drones at the ɪɴᴛᴇʀᴀᴄᴛ research stations and how arctic climates affect drone technology and the ergonomics of piloting a drone. The thesis also provides an overview of the current state of the drone market and the laws and regulations that affect the use of drones. A survey was distributed within ɪɴᴛᴇʀᴀᴄᴛ to map the researchers’ need of, and attitudes towards, drones, followed by exhaustive interviews with researchers and other key figures. Field testing at Tarfala Research Station provided complementing data. The primary insight from the study was that the researchers’ need, as well as the tasks and methods that they employ, vary greatly. Another insight was that many researchers want to use drones primarily as a sensor platform to collect data from large areas in a short time span. A situation-based drone recommendation and a concept proposal for a simple water sampling solution were made based on the results of the study<br>Detta är ett examensarbete utfört av Maria Ader och David Axelsson, studenter på civilingenjörsprogrammet Design och Produktframtagning på KTH, med masterinriktning Teknisk Design. Arbetet är utfört åt ÅF i syfte att bidra till EU-projektet ɪɴᴛᴇʀᴀᴄᴛ. Iɴᴛᴇʀᴀᴄᴛ är EU:s satsning på klimatforskning i Arktis och syftar till att “koordinera och harmonisera forskning och miljöbevakning som bidrar till vår kunskap och förståelse av förändringar som sker i de arktiska miljöerna.” Ett av tolv delprojekt inom ɪɴᴛᴇʀᴀᴄᴛ-projektet syftar till att öka medvetenheten om drönarteknologi och sensorer bland forskare och föreståndare på forskningsstationerna inom ɪɴᴛᴇʀᴀᴄᴛ, samt att göra drönarindustrin medveten om nya potentiella användningsområden. En drönare är ett obemannat luftfartyg, d.v.s. en flygfarkost utan pilot ombord. Drönare benämns ibland som “UAS” och “UAV”. I den här rapporten används främst den engelska termen “drones”. Detta examensarbete undersöker behovet av drönare på de forskningsstationer som är delaktiga i ɪɴᴛᴇʀᴀᴄᴛ och hur det arktiska klimatet påverkar drönartekniken och ergonomin. Arbetet kartlägger även drönarmarknaden och de lagar och regler som påverkar användandet av drönare. En utförlig studie genomfördes, där forskarnas behov av drönare undersöktes. En enkät skickades ut inom ɪɴᴛᴇʀᴀᴄᴛ och utförliga intervjuer genomfördes med forskare och andra nyckelpersoner. Ett studiebesök på Tarfala forskningsstation kompletterade med fältdata. Den främsta insikten från studien var att behov, arbetsuppgifter och metoder varierar mycket mellan de olika forskarna. En annan insikt var att många ville använda drönare som sensorbärare, och på så sätt insamla data från stora områden på kort tid. Resultatet från studien låg till grund för en situationsbaserad drönarrekommendation samt ett konceptförslag för en enkel vattenprovtagningslösning.
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Fuchs, Matthias. "Soil Organic Carbon Inventory and Permafrost Mapping in Tarfala Valley, Northern Sweden : A first estimation of the belowground soil organic carbon storage in a sub-arctic high alpine permafrost environment." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-93116.
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Permafrost regions in the Northern Hemisphere store large amounts of organic carbon and are vulnerable to climate change. Due to a sustained warming of the climate, strongest in the northern high latitudes, permafrost thaws and organic carbon could be released in significant amounts which should not be neglected. This study investigates the soil organic carbon (SOC) storage in the Tarfala Valley (600 – 2’100 m a.s.l.), Northern Sweden, and aims to give a first estimation of the total carbon stock in a sub-arctic high alpine permafrost environment. Further the study describes the actual extent of permafrost in the Tarfala Valley. To achieve these aims, two field studies were carried out, one in summer to collect soil samples and one in winter to measure the bottom temperature of snow (BTS). In addition, the soil samples were analysed in the laboratory for bulk density, loss on ignition and elemental analyses. The estimated total SOC in the Tarfala catchment area of 31.2 km2 is 23.0 kt C for 0 – 30 cm and 28.2 kt C for 0 – 100 cm, which is on average 0.9 kg C m-2 for the upper meter of soil in the study area. Even though the soil organic carbon values are relatively low, these results contribute to the on-going soil organic carbon inventories in the circum-arctic. In Tarfala Valley, permafrost can be considered as continuous at an altitude above 1’561 m a.s.l., discontinuous above 1’218 m a.s.l. and sporadic above 875 m a.s.l. based on a logistic regression model with the altitude as single independent variable. This implies that most of the permafrost affected ground is at an altitude where only sparse or no vegetation is present and only low amounts of organic carbon is stored. In brief, Tarfala Valley cannot be considered as a permafrost carbon hotspot, because this sub-arctic alpine environment does not have the potential to release large amounts of carbon as a result of climate warming and permafrost thawing.<br>Permafrost regioner i norra halvklotet lagrar stora mängder av organiskt kol och är känsliga för klimatförändringar. På grund av en pågående klimatuppvärmning, som är starkast i nordliga höga breddgrader, kan permafrosten tina och frisläppa stora mängder av organiskt kol som skulle kunna ha oförutsedda konsekvenser. Denna studie undersöker organiskt kol lagring i marken i Tarfaladalen (600 – 2’100 m.ö.h.), i norra Lappland i Sverige och försöker att beräkna den totala mängden av organiskt kol lagrad i denna subarktiska högalpina miljö. Denna studie beskriver ytterligare den aktuella permafrostutbredningen i Tarfaladalen. Hela examensarbetet är baserat på två fältstudier varav en genomfördes på sommaren för att samla in jordprover och den andra genomfördes på vintern för att mäta bottentemperaturen av snön. Jordprover analyserades i laboratorium för bulk density, loss on ignition och elemental analysis metoderna. Det totalt beräknade organiskt kol i marken i 31.2 km2 stor Tarfaladalen omfattas 23.0 kt C för 0 – 30 cm och 28.2 kt C för 0 – 100 cm, som resulterar i ett medelvärde av 0.9 kg C m-2 för första övre metern av marken. Även om de beräknade mängderna av organiskt kol är ganska små, så bidrar denna studie till de pågående undersökningarna kring organiskt kol i permafrostmarken runt arktis. Permafrostförekomsten i Tarfaladalen betraktas som kontinuerlig över 1’561 m.ö.h. och diskontinuerlig mellan 1’218 och 1’561 m.ö.h. Mellan 875 och 1’218 m.ö.h. betraktas permafrosten som sporadisk. Dessa värden baseras på en logistisk regressionsmodell med höjden som enda variabel men visar att den stora delen av permafrostmarken ligger på hög altitud, vilket innebär att det bara finns lite eller ingen vegetation och inga stora mängder av organiskt kol i permafrostmarken. Slutligen kan man säga att Tarfaladalen inte är någon hotspot för organiskt kol eftersom det där området inte har någon stor potential att släppa fri stora mängder av organiskt kol under ett varmare klimat och tinande permafrosten.
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Betts-Piper, Alexandra A. "Chrysophyte stomatocyst-based paleolimnological investigations of environmental changes in arctic and alpine environments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ55890.pdf.
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Jackson, Jennifer Martine. "Changes to the near surface waters of the Canada Basin, Arctic Ocean from 1993-2009 : an examination of the consequences of warming and freshening to the water mass structure and optical environment." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/32586.
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The near-surface water mass structure in the Canada Basin of the Arctic Ocean was examined from 1993 through 2009. This was a period of rapid change due to warming air and ocean temperatures and subsequent sea ice melt. During this time, the Southern Canada Basin transitioned from a perennially ice-covered to an almost seasonally ice-free ocean. It was found that the freshwater from sea ice melt increased the near-surface stratification. Solar radiation was stored below the surface mixed layer as a near-surface temperature maximum (NSTM). From 1993-2009, the NSTM warmed by up to 1.5◦C, freshened by up to 4 salinity units, expanded northwards, and formed at successively shallower depths. Below the NSTM is a temperature minimum identified as the remnant of the previous winter’s surface mixed layer (rML). Similar to the NSTM, the rML warmed by up to 0.5◦C and freshened by up to 2 salinity units from 1993-2009. Using a 1-D model of heat diffusion, it was found that heat from both the NSTM and Pacific Summer Water (PSW) is diffused to the rML. In warmer years, more heat was diffused to the rML from the NSTM. The freshening of both the NSTM and rML was greatest at stations that were located inside the anticyclonic Beaufort Gyre and this is likely because downwelling caused freshwater from sea ice melt to accumulate inside the gyre.
An examination of light attenuation to estimate suspended particle concentrations identified six common attenuation features. These features were at the surface, within the summer halocline, within water that has high fluorescence, within cold water that had the salinity range 32.9 - 33.1, within Atlantic water, and at the bottom. It was found that there was no evidence of increased particle concentrations in the basin from 2003-2008. However, the chlorophyll maximum inside the basin deepened from an average of 45 m in 2003 to 61 m in 2008 and it is likely that this is because the nutricline also descended. The deepening of the chlorophyll maximum is one example of how changes to the near-surface water mass structure from climate change can impact the Arctic Ocean ecosystem.
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Mullen, Patrick Carleton University Dissertation International Affairs. "State interests and the Arctic environmental protection strategy." Ottawa, 1994.
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Tamo, Camille. "Late Holocene Environmental Change Across the Canadian Arctic." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38837.
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Lake sediment cores spanning the last 2000 years from four sites across the Canadian Arctic Archipelago (CAA) document the responses of terrestrial and freshwater ecosystems to regional climate variability. Biogenic silica (BSi) records in cores from Banks Island, NWT (Lake B503; 72.3245, -123.4036, 84 masl), Bathurst Island, Nunavut (PR01; 75.6497, -99.1144, 30 masl), Prince of Wales Island, Nunavut (SW08; 72.3177, -97.2678, 104 masl), and Ellesmere Island, Nunavut (CV03; 79.9211, -82.9348, 363 masl) were used to examine the relationship between diatom production and climate. A pollen record from Prince of Wales Island provided the first high-resolution July temperature reconstruction for the last 1000 years for the central CAA.
Dissolution was evident in three out of the four lakes; core SW08 contained no BSi above detection and cores CV03 and PR01 only contained values above detection in the uppermost sediments, suggesting that the preservation of biogenic silica (BSi) in the sediment is likely influenced by sedimentary carbonates. A BSi sequence from core B503 showed that diatom production was affected by climate changes such as the Medieval Climate Anomaly and the Little Ice Age.
The vegetation on southern Prince of Wales Island underwent marked transitions during the Little Ice Age and Medieval Climate Anomaly, which was mainly observed in the proportion of Cyperaceae and Poaceae. The mean July temperature reconstruction showed a long-term cooling from 1080-1915 CE with a sustained cold period from 1800-1915 CE prior to 20th-century warming. A synthesis of paleoclimate records from across the Arctic demonstrated that pollen-based reconstructions record both high and low frequency climate variability, when sampling resolution is sufficient, and can improve regional climate reconstructions.
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Larouche, Julia. "Environmental Influences on the Genetic Diversity of Bacterial Communities in Arctic Streams." ScholarWorks @ UVM, 2009. http://scholarworks.uvm.edu/graddis/131.
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The National Park Service (NPS) Inventory and Monitoring (I&M) Program is designed to collect baseline data on “vital sign” indicators across the entire NPS system. The project presented in this thesis was designed to supplement to efforts of the Artic Network (ARCN) to catalogue the physical, chemical and biological metrics associated with the Stream Communities and Ecosystems vital sign and to foster a better understanding of the basic structure and function of these remote systems. This data is essential to assess the impacts of current and future environmental change in the ARCN parks. The primary objective of this project was to quantify the genetic diversity of microbial communities of selected arctic stream ecosystems. Microbes are a fundamentally important but poorly understood component of arctic stream ecosystems. They are responsible for recycling organic matter and regenerating nutrients that are essential to the food webs of aquatic ecosystems. Recent research (Jorgenson et al. 2002) in the ARCN parks has shown that two fundamentally different lithologies – ultramafic and non-carbonate – influence terrestrial productivity and impart different geochemical characteristics to stream water. Microbes are found in different stream habitats – sediment (epipssamon) and rock (epilithon) biofilms. In this work we test the hypothesis that these differences in lithology and stream habitat influence the genetic diversity of bacterial biofilm communities in arctic streams and whether these patterns can be correlated to stream biogeochemistry. A microbial community fingerprinting method, T-RFLP, as well as 16S rRNA gene sequencing were used to explore the genetic diversity of microbial communities in sediment and epilithic biofilms in stream reaches that drain watersheds with contrasting lithologies in the Noatak National Preserve, Alaska. Differing patterns in bacterial community composition at both the large-scale (lithology) and small-scale (stream habitat) were observed. Non-metric multidimensional scaling (NMDS) ordination of T-RFLP peaks and Analysis of Similarity (ANOSIM) showed a high degree of separation (ANOSIM P < 0.001) between the non-carbonate and ultramafic lithologies, as well as the two habitats, sediment and epilithon. Significant (P < 0.005, Bonferroni corrected) positive correlations were detected between particular nutrients, base cations, and dissolved organic carbon and bacterial community structure unique to each lithology. Although clone libraries indicated high bacterial OTU diversity within and across stream sites, biogeographical patterns were observed depending on locality type. Rarefaction analyses indicated that streams arising from the non-carbonate lithology may be more diverse than streams arising from the ultramafic lithology. Analysis of MOlecular VAriance (AMOVA) indicated that sediment and epilithon samples had genetically different microbial communities (P = 0.01) and taxonomic identifications revealed markedly different bacterial residents between sediment and epilithon habitats. Our results show relationships at large- and small-scales at the landscape level and in ecological niches within a single stream.
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Williams, Stephen Vincent. "Visual arctic navigation: techniques for autonomous agents in glacial environments." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41135.
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Arctic regions are thought to be more sensitive to climate change fluctuations, making weather data from these regions more valuable for climate modeling. Scientists have expressed an interest in deploying a robotic sensor network in these areas, minimizing the exposure of human researchers to the harsh environment, while allowing dense, targeted data collection to commence. For any such robotic system to be successful, a certain set of base navigational functionality must be developed. Further, these navigational algorithms must rely on the types of low-cost sensors that would be viable for use in a multi-agent system. A set of vision-based processing techniques have been proposed, which augment current robotic technologies for use in glacial terrains. Specifically, algorithms for estimating terrain traversability, robot localization, and terrain reconstruction have been developed which use data collected exclusively from a single camera and other low-cost robotic sensors. For traversability assessment, a custom algorithm was developed that uses local scale surface texture to estimate the terrain slope. Additionally, a horizon line estimation system has been proposed that is capable of coping with low-contrast, ambiguous horizons. For localization, a monocular simultaneous localization and mapping (SLAM) filter has been fused with consumer-grade GPS measurements to produce full robot pose estimates that do not drift over long traverses. Finally, a terrain reconstruction methodology has been proposed that uses a Gaussian process framework to incorporate sparse SLAM landmarks with dense slope estimates to produce a single, consistent terrain model. These algorithms have been tested within a custom glacial terrain computer simulation and against multiple data sets acquired during glacial field trials. The results of these tests indicate that vision is a viable sensing modality for autonomous glacial robotics, despite the obvious challenges presented by low-contrast glacial scenery. The findings of this work are discussed within the context of the larger arctic sensor network project, and a direction for future work is recommended.
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Trofaier, Anna Maria. "The seasonal dynamics of Arctic surface hydrology in permafrost environments." Thesis, University of Cambridge, 2014. https://www.repository.cam.ac.uk/handle/1810/246466.
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Climate-induced landscape evolution is resulting in changes to biogeochemical and hydrologi- cal cycling. In the Arctic and sub-Arctic permafrost zones, rising air temperatures are warming, and in some regions even thawing, the frozen ground. Permafrost is a carbon sink. The thermal state of the ground therefore has important implications on carbon exchange with the atmo- sphere. Permafrost thaw mobilises previously sequestered carbon stocks, potentially turning these high latitude regions into a net carbon source. Borehole temperature and active layer depth measurements are the traditional means for monitoring permafrost, however these point measurements cannot easily be extrapolated to the landscape-scale; Earth Observation (EO) data may be used for such purposes. It is widely recognised that changes in the thermal state of permafrost may be associated with longterm changes in surface hydrology. As the ground shifts from a frozen to a thawed state, Arctic lakes display changes in surface extent. Therefore, it has become common practice to explore lake dynamics, using these as indicators of permafrost change; dynamics being the keyword. Surface hydrology is a dynamic process. Discharge studies in the Arctic and sub-Arctic regions are associated with flashy hydrographs. Currently, however, remote sensing of permafrost lake change is done on the scale of decades without explicitly taking seasonality and rapid hydrolog- ical phenology into consideration. To examine the seasonal changes in Arctic surface hydrology on the landscape scale high temporal resolution data are necessary. Synthetic aperture radar instruments are exemplary for such a task. The PhD research focuses on establishing operational techniques for mapping open surface water using synthetic aperture radar data, investigating straightforward raster classification methods and exploring their feasibility by undertaking map accuracy and sensitivity studies (chapter 3). The results are then used to justify error propagation when developing an auto- mated procedure that creates temporal composites of water body extent. These temporal water body classifications are the main EO product used to identify and image seasonal surface water change in Arctic permafrost environments (chapter 4). Furthermore, a terrain-based hydrolog- ical study is undertaken to explore the context of the detected changes and possible links to relief and stream channel network (chapter 5). The aim of this PhD is to demonstrate a new method of dynamic monitoring using the Euro- pean Space Agency’s Envisat Advanced Synthetic Aperture Radar, recommending its incorpo- ration in longterm lake change studies. Technical feasibility is explored, the inherent trade-off vii between spatial and temporal resolution discussed. An automated surface water change de- tection algorithm is developed and its applicability to monitoring spring floods is assessed; noting possible modifications to the drainage system given present-day land-use and land- cover changes that are taking place in the study area, the hydrocarbon-rich Yamalo-Nenets Autonomous District in the North of West Siberia (chapter 6). The key significance of this research is to improve the current knowledge of Arctic lake change by including spring flood events and seasonality in the equation. Therefore, it is strongly believed that this research is of benefit to the entire permafrost community.
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Keatley, Bronwyn Elizabeth. "Limnological and paleolimnological investigations of environmental change in three distinct ecosystem types, Canadian High Arctic." Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/697.
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Colby, Graham. "Microbial Responses to Environmental Change in Canada’s High Arctic." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39254.
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The Arctic is undergoing a rapid environmental shift with increasing temperatures and precipitations expected to continue over the next century. Yet, little is known about how microbial communities and their underlying metabolic processes will respond to ongoing climatic changes. To address this question, we focused on Lake Hazen, NU, Canada. As the largest High Arctic lake by volume, it is a unique site to investigate microbial responses to environmental changes. Over the past decade, glacial coverage of the lake has declined. Increasing glacial runoff and sedimentation rates in the lake has resulted in differential influx of nutrients through spatial gradients. I used these spatial gradients to study how environmental changes might affect microbial community structure and functional capacity in Arctic lakes. I performed a metagenomic analysis of microbial communities from hydrological regimes representing high, low, and negligible influence of glacial runoff and compared the observed structure and function to the natural geochemical gradients. Genes and reconstructed genomes found in different abundances across these sites suggest that high-runoff regimes alter geochemical gradients, homogenise the microbial structure, and reduce genetic diversity. This work shows how a genome-centric metagenomics approach can be used to predict future microbial responses to a changing climate.
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Harders, Johannes Enno. "Environmental protection of the circumpolar arctic waters : A comparative study and an appraisal of the National Regulatory Systems." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27764.
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Canada, the United States-Alaska, the Soviet Union-RSFSR, Norway, and Denmark/Greenland have non-specific laws apply for the environmental protection of their Arctic lands, waters, and marine spaces. But the piecemeal approaches employed neglect the need for environmentally sound management in respect of the multiple uses of the polar sea's delicate ecosystems. Convenient component elements of Arctic pollution are chosen for examination
-- (1) land-based sources of freshwater pollution and (2) marine-borne pollution resulting from offshore drilling and Arctic shipping. This comparative study moreover serves three objectives: (1) the exposition of the statutory instruments and administrative materials; (2) the evaluation of the national approaches taken for environmental protection generally and Arctic protection specifically; and (3) the appraisal of the accommodation and resolution of conflicts over interests concerning economic uses vis-a-vis environmental protection.
In the chapter on each state a background makes reference
to the national socio-legal and international legal conditions affecting municipal Arctic pollution control. The next section on the national regulatory framework follows the territorial and jurisdictional zones of the coastal state: from land-based operations affecting the freshwaters, to the coastal area, the body of law on shipping and navigation, the environmental provisions
of a 200 nautical mile exclusive economic zone, the continental shelf activities, to the regime on deep sea-bed mining. The latter of which ends this section and provides for the evaluation given in the concluding section on the country in question. The states have taken different avenues in their pollution control enactments: (1) blanket prohibition or the regulation of pollution; (2) the enforcement and supervision of statutory provisions; and/or (3) civil and criminal liability for violations of respective measures. Every state provides precedences for a number of recommendations
in order to facilitate resource uses, environmental
protection, and the integration of the Arctic natives in an ecosystem management approach to environmental protection. Examples are such like Norway's integrated statute on pollution prevention, the United States' legislation on coastal zone management and environmental impact assessments, and Canada's framework on Arctic shipping and Arctic pollution prevention.<br>Law, Peter A. Allard School of<br>Graduate
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Loseto, Lisa Lucia. "Methylmercury sources in the Canadian High Arctic." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26515.
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Mercury is increasing to toxic levels in Arctic biota living at the top of food webs. The rapid bioaccumulation and biomagnification of methylmercury (MeHg) in food chains, and the subsistence lifestyle of northern populations, has resulted in high levels of Hg in their blood. No prior measurements of MeHg sources to Arctic ecosystems have been made. In southern latitudes wetlands are considered important sources of MeHg with sulfate-reducing bacteria (SRB) thought to be responsible. Thus, the production of MeHg in Arctic wetlands was evaluated as well as SRB presence.
Arctic wetlands were further evaluated as sources of MeHg in Arctic ecosystems, as well since snowmelt water provides 60 to 80% of water to Arctic terrestrial systems it was also evaluated as a source of MeHg.
This was the first study to evaluate sources of MeHg entering Arctic ecosystems, and showed that although wetlands produced MeHg, the export to downstream lakes was dependant on site characteristics such as DOC levels, furthermore snowmelt water was the most significant source of MeHg to Arctic ecosystems measured here. (Abstract shortened by UMI.)
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Attalla, Daniela, and Alexandra Tang. "Drones in Arctic Environments: Snow Change Tracking Aid using Sensor Fusion." Thesis, KTH, Mekatronik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235928.
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The Arctic is subject to rapid climate changes that canbe difficult to track. This thesis aims to provide a user case in which researchers in the Arctic benefit from the incorporation of drones in their snow ablation research. This thesis presents a way to measure ablation stakes with the help of a sensor fusion system mounted on a drone. Ablation stakes are stakes placed on a grid over glaciers in the Arctic, below the snow and ice surface, during the winter and then measured during the summer to keep track of the amount of snow that has melted throughout the mass balance year. Each measurement is given by physically going to these stakes. The proposed solution is based on estimating the heights of the ablation stakes using a forward-faced LiDAR on a servo motor and a downward-faced ultrasonic sensor. The stake height is interpreted as the highest ultrasonic distance while the forward-faced sensor system is detecting an object within 3 m distance. The results indicate that stake height estimation using the proposed concept is a potential solution for the researchers if the roll and pitch angles of the sensor system are compensated for.<br>Arktis är ett område som är utsatt för stora klimatförändringar, vilka kan vara svåra att spåra. Målet med arbetet är att föreslå, utveckla och utvärdera ett koncept där forskare i arktiska områden gagnas av att använda drönar- och sensorteknik i deras arbete gällande snöablation. Arbetet presenterar ett alternativ till att mäta utplacerade referensstavar med hjälp av ett integrerat sensorsystem monterat på en drönare. Dessa referensstavar borras ned, under snö- och isytan, över ett rutnät på glaciärerna i Arktis under vintern för att sedan mätas under sommaren med avsikt att studera mängden snö som smälter under året. Varje mätning görs således genom att fysiskt gå till varje enskild referensstav. Det framtagna konceptet uppskattar höjden på referensstavarna med hjälp av en framåtriktad LiDAR monterad på en servomotor och en nedåriktad ultraljudssensor. Höjden är uttytt som det högsta ultraljudsavståndet då det framåtriktade sensorsystemet detekterar ett föremål inom 3 m avstånd. Resultaten tyder på att det föreslagna konceptets höjduppskattning av referensstavar är en potentiell lösning inom problemområdet om systemets roll- och pitchvinklar kompenseras för.
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Blaen, Phillip John. "Hydroecological response of Arctic rivers to climate change." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4247/.
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Although the Arctic is one of the most vulnerable regions to climate change, links between hydrology and ecology in high-latitude northern river basins are not well understood. Interdisciplinary research over three summer melt seasons (2010 to 2012) in the Kongsfjorden area of northwest Svalbard identified process connections between conceptual water sources, physicochemical habitat, and ecological structure and functioning in river basins. Water source dynamics determined from hydrochemical and isotopic data indicated differences in meltwater and groundwater contributions to river flow which varied both spatially and temporally at seasonal and year-to-year timescales. Non-glacier-fed rivers were characterised by less variable flow regimes, warmer water temperature, lower suspended sediment concentration and more stable channel morphologies. Several physicochemical habitat variables, notably water temperature and channel stability, were related significantly to rates of nutrient uptake and macroinvertebrate community structure. These data suggest that a future shift towards groundwater-dominated flow regimes may increase biotic diversity and rates of nutrient cycling in some high-latitude rivers. Key research findings are synthesised in conceptual models and provide a framework to understand the hydroecological response of these Arctic river systems to climate change.
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Pollock, Russell (Russell Clayton). "Economic feasibility of shipping containers through the Arctic." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53089.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2009.<br>Includes bibliographical references (leaf 51).<br>As the Arctic ice cover continues to retreat, the possibility of regular transit through the Arctic becomes an increasing reality. Liner companies could take advantage of distance savings (up to 4000 nautical miles less than existing routes) available from transit through the Arctic by offering faster port-to-port voyage times while simultaneously reducing voyage expenses. The purpose of the study is to investigate the economic feasibility of a liner service with shipping routes through the Arctic. To accomplish this, information pertaining to Arctic conditions, containerships and icebreakers, and container ports was collected and used to build a model that estimates the expense and time of port-to-port voyages through the Arctic. Different combinations of vessels, routes, and speeds through the Arctic were evaluated with the model. The expense and time of the Arctic voyages were then compared to the equivalent existing liner routes. The likelihood of year-round reliable containership service through the Arctic in the future depends on one's perspective. One the one hand, it won't happen for decades due to the presence of ice. Current predictions of a largely ice-free Arctic range from 2030 to later than 2100. On the other hand, if some favorable assumptions are made, it deserves serious consideration once minimally ice-strengthened containerships are able to be reliably escorted through the Arctic at a speed of 10kts.<br>by Russell Pollock.<br>S.M.
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Pier, Melanie Dawn. "Vascular plants as indicators of polychlorinated biphenyl contamination in terrestrial Arctic environments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ59397.pdf.
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Olsson, Sofia. "Drones in Arctic Environments: Development of Automatic Water Sampler for Aerial Drones." Thesis, KTH, Maskinkonstruktion (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-236506.
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The purpose of the thesis is to develop a water samplingsolution to use with an aerial drone for remote water sampling and to investigate the feasibility of the system. The actuating hypothesis is that using a drone for this application will have many benefits over the manual methods, for example to reach inhospitable areas, improve data gathering and offer a safer work situation for the researchers. The research method has been empirical and exploring, by rapidly develop prototypes based on a pre-study, test the full test system and draw conclusions regarding the feasibility of the application based on the tests. Through the pre-study of the current water sampling process through interviews and a survey, a general user case was created. It was studied with a mechatronic perspective to understand how the current water sampling process could be adjusted to function remotely with a drone. The main focuses when developing the water sampler was to design a product independent from the drone with full automatic function, and to maximize its water volume capacity while minimizing the weight of the sampler to manage the drones barload constraints of 1 kg. Through workshop activities and methods from TRIZ theory, several concepts were evaluated. The main idea was to integrate the laboratory bottle with the water sampler. Two physical prototypes were designed to test the function of the concepts and evaluate them against the Ruttner sampler. The first prototype, the Wheel, has a simple design, is lightweight and mechanic while the second prototype, the Combination, is more complex, heavier and uses a mechatronic system. The prototypes were evaluated through functional tests to investigate its design and suitability to be used with a drone for water sampling. The behavior of the full test system, consisting of the Wheel sampler and a drone, was observed and analyzed through drone data when gathering water samples. The thesis demonstrates through field tests that the system, consisting of drone and developed water sampler, succeeds in gathering water samples remotely. Through tests of the water samplers, the thesis also shows the benefits and disadvantages of their proposed design for water sampling.
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Mocellin, Jane Schneider Pereyron. "A behavioural study of human responses to the arctic and antarctic environments." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29024.
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This is a study of human response to the Arctic and Antarctic environments. It is based on two sources of data: the content analysis of original diaries of polar explorers, and the behavioural evaluation of contemporary crews in polar locations. In the latter, four polar stations were chosen, two in each polar region with a total of fifty-five experimental subjects. Twenty-seven other subjects acted as controls for both polar regions: a northern control group located at a semi-isolated site in Canada, and the southern group located in an Argentinian city.
Methods applied in this research included the design and coding of categories which were content analyzed from the original diaries of explorers, and on-site procedures. On-site procedures included psychometric material, participant-observation reports and unstructured interviews. Fifteen behavioural measures within the domain of personality, perception of the environment, affection, social stress and community behaviour were administered.
It was hypothesized that the human response would be similar in both polar regions because of environmental and sociological similarities, and that the polar setting would affect men and women in a negative way. Results showed that: (i) the polar environment is not perceived as stressful by the crews - a low anxiety state across both polar regions was found, (ii) traumatic experiences of the explorers had led to the perception of the environment in a negative perspective - yet the winter seemed to be a relaxing phase for the crews rather than stressful, (iii) personnel stationed at polar sites may possess special characteristics which distinguish them from the majority of the population, (iv) although cross-cultural differences exist, they are not as strong as might be anticipated - the environment exerts a unifying influence, (v) differences in gender-response are difficult to assess due to the small number of women subjects, but some differences with controls were noted.<br>Graduate and Postdoctoral Studies<br>Graduate
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Hill, James A. "Environmental influences on the production of Arctic halocline and deep water." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23209.
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Pease (1987) related the effects of atmospheric forcing, mainly temperature and wind fields, to the size of coastal polynas. Using Pease's formulation and Killworth's (1977) plume model as applied by Melling and Lewis (1982), the effects of atmospheric forcing on brine injection into the Arctic pycnocline are investigated. This paper will discuss the likelihood of coastal polynas as a source for denser abyssal waters. A standard case was developed for the model with initial conditions taken from Melling and Lewis (1982) and Pease (1987) for comparison with individual sensitivity experiments. Ten environmental parameters were individually examined for their influence on the plume depth after 90 days. The standard case resulted in a 90-day plume depth of 436 meters. A submarine canyon case was simulated, resulting in plume penetration to over 1300 meters in 90 days. Further experiments used actual T-S soundings. Finally, a 20 kilometer wide plume is shown to penetrate to almost 600 meters in 90 days. Keywords: Arctic; Halocline; Deep water; Plume flow; Polyna; Theses. (JHD)
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Whittleston, David Patrick. "The impact of Arctic amplification on the extratropical jets." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111583.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2017.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references.<br>Since the 1990's, greenhouse gas forcing has warmed the Arctic at twice the rate of lower latitudes, coinciding with a dramatic decline in Arctic sea ice extent. This manifestation of climate change has ignited a lively and ongoing debate regarding if Arctic warming will significantly influence extreme weather in the extra-tropics. This thesis offers three distinct contributions to the dialogue. Firstly, results are presented from a suite of targeted climate model experiments designed to establish how ice-forced and snow-forced anomalies interact and propagate through the atmosphere. Results suggest that high snow anomalies can suppress the October-November atmospheric response by interfering with the forcing of hemispheric (wave one) atmospheric dynamics. Intriguingly, the simulations do not force the persistent stratospheric response reported in similar experiments. This may be a consequence of transient or seasonally-restricted surface forcing. Secondly, multi-model projections of future wintertime North Atlantic and North Pacific tropospheric jets are analyzed using a novel Bayesian weighting technique. This approach is shown to reduce systematic bias and indicates that future forcing of the jets - due to greenhouse gas emissions - will be first order linear (i.e. independent of historical bias). Results suggest that the widely reported future poleward shift at the level of the eddy-driven jet is far from robust. Lastly, an attempt is made to distill the current level of consensus within the scientific community using expert elicitation. Results reveal a fairly evenly split on if Arctic warming has already had a significant impact on the mid-latitude jets, but a strong consensus that it will in the future.<br>by David Patrick Whittleston.<br>Ph. D.
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Lindeberg, Carola. "Long-term changes of mercury, lead and persistent organic pollutants in arctic environments." Doctoral thesis, Umeå : Department of Ecology and Environmental Science, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1060.
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Newman, Maria. "Law and Policy: Methods for Protecting the Arctic National Wildlife Refuge." Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/scripps_theses/887.
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My thesis examines the Arctic National Wildlife Refuge (ANWR), which is the site of ongoing debate between environmentalists and the oil industry. I begin by analyzing both sides’ claims about the area’s value and establishing that the coastal zone of the ANWR, whose fate is the most precarious, should be protected for both environmental and cultural reasons. I then examine two methods for protection: the common law, and regulation. I conclude that only through proactive regulation can the ANWR continue to thrive.
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Stamoulis, Catherine 1968. "Analysis of ice-induced acoustic events in the central arctic." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10191.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997.<br>Includes bibliographical references (leaves 244-247).<br>by Catherine Stamoulis.<br>Ph.D.