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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Exploration and resource utilization in northwestern Arctic Alaska before 1855.

Foote, Don Charles. January 1965 (has links)
No description available.
432

Mineral weathering by dissolved organic carbon in subarctic fens

Heyes, Andrew January 1990 (has links)
No description available.
433

Observation and characterization of low-level air temperatures above a subarctic snowpack

Ross, Julie, 1959- January 1988 (has links)
No description available.
434

"There's life and then there's school" : school and community as contradictory contexts for Inuit selfknowledge

Douglas, Anne S. January 1999 (has links)
No description available.
435

The Design and Testing of a Waterwaste Treatment Process suitable for Arctic Application

Bromley, David E.G. 10 1900 (has links)
The purpose of the project was to design and test the components of a potential package sewage treatment plant suitable for the Arctic environment. The designed treatment plant was simplistic in concept while utilizing the advantages of both biological and physical-chemical treatment. The system was tested over a ten-week period. The emphasis of the testing was on treatment of high-strength wastes. In addition the effects of temperatures and system start-up-shutdown conditions were assessed. The results indicated that the system operated well under most of the conditions tested. Both the physical-chemical and biological processes complemented each other with the former providing the necessary treatment at start-up and the latter providing low cost treatment once the system had been in. operation for a month. With the high degree of treatment performance achieved, it was felt the process was feasible for Arctic application. However, further testing was recommended to develop the complete package unit. / Thesis / Master of Engineering (ME)
436

Ip25: A Molecular Proxy of Sea-ice Duration in the Bering and Chukchi Seas

Sharko, Cecily J 01 January 2010 (has links) (PDF)
Seasonal sea ice is an important component of the global climate system. Sea ice influences exchange rates of heat, moisture, and gas between the ocean and atmosphere. Sea ice also plays critical roles in high latitude ecosystems and marine carbon cycling. Records of sea-ice extent and duration in the Arctic Ocean and its marginal seas through geologic time are valuable resources for better understanding the intricate relationships between sea ice and climate. IP25, a compound biosynthesized exclusively by diatoms associated with sea ice, has been used to construct qualitative records of sea ice from sediment cores in some areas of the Arctic. However, IP25 has not previously been applied to sediments from the Bering and Chukchi Seas. This area exhibits a wide range of interannual seasonal ice duration, which makes the region a promising natural laboratory for developing a quantitative core-top calibration between sea ice and the IP25 biomarker. A sample suite of surface sediments from the Bering and Chukchi Seas representing a range of latitudes (60-72o N) and durations of sea ice per year (0.5-11 months/year) are analyzed for this study. Gas chromatography/mass spectrometry analysis of sediment solvent extracts reveals the presence of IP25 in all samples and higher IP25 concentrations in the Chukchi Sea compared to in the Bering Sea. IP25 concentrations are compared with data for several sea surface conditions: mean annual sea-ice duration, sea surface temperature and salinity, and insolation data. An exponential relationship between TOC-normalized IP25 concentration and average annual duration of sea ice is identified. Negative exponential relationships are identified between IP25 and the other sea surface conditions: average annual and August sea surface temperature and average annual and August sea surface salinity. Exponential relationships are also identified between TOC-normalized IP25 concentrations and insolation, and insolation coupled with sea-ice concentration. IP25 in surface sediments is a viable quantitative proxy for sea-ice duration in the Bering and Chukchi Seas. However, sea surface conditions, such as temperature, salinity, sea-ice duration/concentration, and insolation are not independent variables. Therefore it is difficult to determine which of these environmental factors has/have the most influence on IP25 production. Further research and statistical analysis may serve to refine these relationships.
437

Community Food Security and Wellbeing: Evaluation of the Nutrition North Canada Cooking Circle Program in Paulatuk, NWT

Dedyukina, Lena 16 August 2023 (has links)
Limited research exists on the role of community food programs, such as cooking circles, in Canadian Arctic communities. This research investigates the Nutrition North Canada cooking circle program in the Inuvialuit (Inuit) hamlet of Paulatuk, NWT. The objectives are to 1) collaboratively evaluate the program's impact on healthy food intake, and awareness/knowledge accumulation regarding healthier eating and meal preparation techniques; 2) assess the program's intangible (e.g., social, cultural, and mental health) benefits to participants and community wellbeing; and 3) analyze the potential for consistent country food integration; 4) to generate a culturally relevant logic model; 5) to evaluate program implementation in terms of key enablers and barriers - namely, funding, space and equipment, and human resources. This research applies a Community-Based Participatory Research approach to implementing a collaborative process and outcome program evaluation, with necessary modifications due to the Covid-19 pandemic. Methods include logic model co-design, document analysis of NNC annual reports (n = 9) and proposals (n = 2), a series of regular/weekly iterative videoconference conversations with the Paulatuk cooking circle facilitator out of which two were transcribed and analyzed (n = 2), videoconference semi-structured interview with a regional program manager (n = 1), telephone semi-structured interviews with cooking circle facilitators from other communities (n = 4), telephone (n = 1) and in-person (n = 12) semi-structured interviews with Paulatuk cooking circle participants. The Mukluk Logic Model played an instrumental role in the conceptualization of the process evaluation, recognizing the specificity of location, program facilitation, and culture. The process evaluation results indicated that the long-standing sustainability of Paulatuk's cooking circle program is directly related to the consistency of program funding, community-engaged facilitation practices, and creative utilization of the community's multi-purpose space for program activities. However, significant barriers to program implementation limit program sustainability. These include funding amounts and distribution, limitations related to space and equipment, and a challenging human resources context (hiring and retention). The cooking circle participants reported an increase in intake of healthy food, awareness of healthy eating/cooking, and positive social and mental health aspects of the program. A considerable effort from local and regional stakeholders is required to integrate country food into program activities. This study provides insight into cooking circle program implementation in a Canadian Arctic community, illustrating the utility of qualitative process evaluation research in this context and generating important knowledge and insights to better support northern community-based food preparation programs. Additionally, this research highlights the role of local-scale initiatives in supporting food security, overall wellbeing, and integration of country food in program activities in remote, Arctic communities.
438

Optimal foraging in an Arctic herbivore : How does the foraging behaviour of Svalbard reindeer (Rangifer tarandus platyrhynchus) respond to seasonal changes from summer through autumn of the Arctic tundra?

Djurberg, Emma Limosa January 2023 (has links)
Foraging decisions of large herbivores can be affected by many factors and have great effect on both above- and below-ground ecosystems. Here, I determine to which degree temporal (seasonality), or spatial (habitat) factors influence the foraging behaviour of Svalbard reindeer (Rangifer tarandus platyrhynchus) and asses if small-scale foraging behaviour correlates with an animals’ patch residence time. I analysed behavioural observations on 15 Svalbard reindeer between summer and autumn 2022, recording both behaviour and habitat use. Using mixed-effects multinomial logistic regression, the interaction between seasonal change from summer to autumn and habitat best explained the variation in Svalbard reindeer foraging behaviour. The foraging behaviour “standing-grazing” was found to have the highest observed amount in all habitat types and increased over the growing season. Contrastingly, the foraging behaviour of “walking-grazing” had its highest abundance in the beginning of the study period, and then decreased over the course of the season for all analysed habitats. In addition, “walking-grazing” was found to be significantly correlated with patch residency time and decreased the longer an individual stayed in a patch. With presumable high plant quality early in the season, my results imply how Svalbard reindeer are greatly stationary foragers, but prioritizing to become relatively mobile when it is beneficial. Thus, highlighting how Svalbard reindeer respond dynamically to shifts in foraging conditions. These findings provide knowledge about what factors may impact the foraging behaviours of Arctic herbivores and helps contribute to a broader understanding of how changes in foraging behaviours may alter arctic ecosystems.
439

Chemical composition of summertime High Arctic aerosols

Siegel, Karolina January 2020 (has links)
This thesis presents new insights into the chemical composition of semi-volatile compounds in aerosol samples collected in the central Arctic Ocean close to the North Pole in September 2018. The central Arctic Ocean is an inaccessible location due to the lack of land areas along with heavy pack ice conditions. Therefore, large knowledge gaps remain to understand the Arctic climate system, and in particular the role of aerosol particles in its pristine atmosphere. The chemical composition of the aerosol samples was analysed on a molecular level using High Resolution Time-of-Flight Chemical Ionization Mass Spectrometry coupled to a Filter Inlet for Gases and AEROsols (FIGAERO-HRToF-CIMS). The analysis revealed a significant signal from compounds that are likely from marine sources. One important precursor for marine aerosols is dimethyl sulfide (DMS), a gas released by phytoplankton and ice algae in the Arctic Ocean. DMS oxidises in the atmosphere to produce oxidation products that can contribute to aerosol growth. Analysis of air mass origin with backward trajectories showed that the highest ambient DMS concentrations originated from marine areas around the pack ice. However, no correlation could be shown within the pack ice between ambient DMS and its oxidation product methanesulfonic acid (MSA) in the particle phase. As FIGAERO-HRToF-CIMS is commonly used in areas with higher particle concentrations and has never been used in the central Arctic before, this thesis further demonstrates its suitability for measurements of aerosol chemical composition in this remote region. / Denna avhandling ämnar att presentera nya kunskaper om den kemiska sammansättningen av halvflyktiga föreningar i aerosolprover som samlades in i Norra ishavet nära Nordpolen i september 2018. Den innersta delen av Norra ishavet är svårtillgängligt på grund av bristen på fasta landområden ihop med kompakt packis. Därför kvarstår stora kunskapsluckor i förståelsen av klimatsystemet i Arktis, och i synnerhet aerosolpartiklars roll i dess orörda atmosfär. Den kemiska sammansättningen av aerosolproverna analyserades på molekylnivå med högupplöst kemisk joniseringsmasspektrometri kopplad till ett filterinsläpp för gaser och aerosoler (FIGAERO-HRToF-CIMS). Analysen visade på en tydlig signal från föreningar som sannolikt har marina källor. En viktig kemisk föregångare till marina aerosoler är dimetylsulfid (DMS), en gas som frigörs av fytoplankton och isalger i Ishavet. DMS oxiderar i atmosfären till oxidationsprodukter som kan bidra till en storleksökning av aerosoler. Genom analys av provluftens ursprung med trajektorieanalys visades att de högsta DMS-koncentrationerna kom från havsområdena runt packisen. Ingen korrelation kunde emellertid visas inom packisområdet mellan DMS i gasfas och dess oxidationsprodukt metansulfonsyra (MSA) i partikelfas. Eftersom FIGAERO-HRToF-CIMS ofta används i områden med högre partikelkoncentrationer och aldrig har använts i de inre delarna av Arktis tidigare, visar denna avhandling även att tekniken är lämplig för att mäta den kemiska sammansättningen av aerosoler i detta avlägsna polarområde.
440

SuperLine : A Framework for Domestic Urbanism

Johansson, Linnea January 2022 (has links)
How we organize cities and design their spatial configuration is always relevant because it reflects politics, financial interests, and territorial dynamics. But the city is also a powerful spatial system as its framework defines the domesticity that is possible within it. This report aims to investigate the relationship between urbanization and domesticity. How can urbanization be reframed, theoretically and spatially, in relation to domesticity? The research is conducted using a subjective and feminist approach. This entails acknowledging the authors position in the research, both emotionally and politically. It also uses a non-binary approach, which refers to an active stance against the false dichotomization of concepts and abandoning restrictive binary modes of discussing, developing, and thinking about spatial concepts. Using literature review, case studies, design explorations, and photography, this report seeks to reframe urbanization beyond the urban-rural dichotomy, situate the discourse in the arctic region, and eventually propose a framework for a new urbanism in northern Sweden which is based in domesticity. The report argues that we must understand all landscapes as devices of urbanism, that urbanization is a domestication of territory, and that strong connections and shared infrastructures across all territory would allow for a more sustainable relationship between urban and rural conditions. This discourse resulted in an architectural proposal of a new framework for urbanization and domesticity in coastal Västerbotten. As conclusion, the report reflects on the danger of its theoretical nature and the interesting possibility to implement the project in a larger territory. Finally, it restates the significance of our urban frameworks.

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