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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.
231

American Arctic Exploration: A Social and Cultural History, 1890-1930

Lukens, Robert Douglas January 2011 (has links)
The Arctic has long held power over the American imagination as a place of otherworldly beauty, life-threatening elements, and dangerous wildlife. Nearing the end of the nineteenth century, in a time of great anxiety about the direction of American society, the region took on new significance. As a new frontier, the Arctic was a place where explorers could establish a vigorous and aggressive type of American manhood through their exploits. Publications, lectures, newspaper accounts, and other media brought the stories of these explorers to those at home. Through such accounts, the stories of brave explorers counteracted the perceived softening of men and American society in general. Women played a crucial role in this process. They challenged the perceived male-only nature of the Arctic while their depiction in publications and the press contradictorily claimed that they retained their femininity. American perceptions of the Arctic were inextricably intertwined with their perceptions of the Inuit, the indigenous peoples that called the region home. In the late-nineteenth-century, Americans generally admired the Inuit as an exceptional race that embodied characteristics that were accepted in American Society as representing ideal manhood. Over time the image of the Arctic in American society shifted from a terrifying yet conquerable place to an accessible and open place by the 1920s. This "friendly Arctic" - a term coined by anthropologist Vilhjalmur Stefansson - appeared to be a less threatening and intimidating place. Due to new technologies and geographical accomplishments, the Arctic appeared to become more accessible and useable. As the Arctic's depiction in American society gradually shifted towards a more "friendly Arctic," the role of women in the Arctic shifted as well. Women increasingly participated in this new friendly Arctic. While still claiming that their femininity remained, both fictional and non-fictional female explorers participated in a wide array of Arctic activities. The image of the Inuit, too, underwent a transformation. Americans viewed the Inuit with less respect than in prior decades. Open Arctic theories and rising technological advancements contributed to this change. The decline in respect also stemmed from beliefs that the indigenous northerners were set on a course of extinction or assimilation. Ultimately, the late-nineteenth- and early-twentieth-century relationship between Americans and the Arctic laid the foundation for present-day views of the region and the Inuit. / History
232

Depth distributions of high Arctic polychaetes.

Curtis, Mark A. January 1969 (has links)
No description available.
233

The postglacial dispersal of freshwater fishes in northern North America

McPhail, John Donald January 1963 (has links)
No description available.
234

An investigation of the feasibility of total air support for supply operations in a selected area of the eastern Canadian Arctic.

Anderson, William Reginald January 1970 (has links)
No description available.
235

Lake in the Sky

Glasson-Darling, Meredith Elane 27 June 2019 (has links)
This is a fiction novel about grief, isolation, and loss that takes place in an unnamed rural whaling village in Arctic Alaska. There is also a time-traveling dragon in it. / Master of Fine Arts
236

Dendrochronological Potential of Salix Alaxensis from the Kuujjua River Area, Western Canadian Arctic

Zalatan, R., Gajewski, K. January 2006 (has links)
This study presents the first annually-resolved chronology using Salix alaxensis (Anderss.) Cov from Victoria Island, Northwest Territories, Canada, an area well north of treeline. Forty-one samples were collected and examined for subsequent analysis. However, crossdating was difficult because of locally absent or missing rings and the narrowness of the rings, and ultimately thirteen stems were crossdated and used to evaluate their dendroclimatological potential. The chronology spans 74 years (1927-2000) and could potentially be extended further using subfossil wood. Precipitation data from December of the previous year to March of the current year were the most consistently and highly correlated with ring width. This suggests that the recharge of the soil moisture by early summer snowmelt is a key factor limiting growth of these shrubs.
237

Dendrochronological Potential of the Arctic Dwarf-Shrub Cassiope Tetragona

Rayback, Shelly A., Henry, Gregory H. R. January 2005 (has links)
In this report, we describe the use of dendrochronological techniques on the circumpolar, evergreen dwarf-shrub, Cassiope tetragona. Using techniques such as crossdating and standardization, and the software programs COFECHA and ARSTAN, we developed C. tetragona growth and reproduction chronologies for sites in the Canadian High Arctic. High-resolution chronologies may be used to reconstruct past climate and phase changes in large-scale modes of atmospheric circulation (e.g. Arctic Oscillation, North Atlantic Oscillation), to investigate the growth and reproductive responses of the plant to ambient and manipulated environmental variables, and to reconstruct the plant’s past ecohydrology (δ¹⁸O, δD, δ¹³C), gas exchange (δ¹³C) and mineral nutrition (δ¹⁵N). As C. tetragona is a circumpolar species, chronologies may be developed throughout the Arctic at sites where no trees exist, and thus provide new information on the past climate and environmental history of sites and regions previously unstudied.
238

The Arctic Atmosphere : Interactions between clouds, boundary-layer turbulence and large-scale circulation

Sotiropoulou, Georgia January 2016 (has links)
Arctic climate is changing fast, but weather forecast and climate models have serious deficiencies in representing the Arctic atmosphere, because of the special conditions that occur in this region. The cold ice surface and the advection of warm air aloft from the south result in a semi-continuous presence of a temperature inversion, known as the “Arctic inversion”, which is governed by interacting large-scale and local processes, such as surface fluxes and cloud formation. In this thesis these poorly understood interactions are investigated using observations from field campaigns on the Swedish icebreaker Oden: The Arctic Summer Cloud Ocean Study (ASCOS) in 2008 and the Arctic Clouds in Summer Experiment (ACSE) in 2014. Two numerical models are also used to explore these data: the IFS global weather forecast model from the European Center for Medium-range Weather Forecasts and the MIMICA LES from Stockholm University. Arctic clouds can persist for a long time, days to weeks, and are usually mixed-phase; a difficult to model mixture of super-cooled cloud droplets and ice crystals. Their persistence has been attributed to several mechanisms, such as large-scale advection, surface evaporation and microphysical processes. ASCOS observations indicate that these clouds are most frequently decoupled from the surface; hence, surface evaporation plays a minor role. The determining factor for cloud-surface decoupling is the altitude of the clouds. Turbulent mixing is generated in the cloud layer, forced by cloud-top radiative cooling, but with a high cloud this cannot penetrate down to the surface mixed layer, which is forced primarily by mechanical turbulence. A special category of clouds is also found: optically thin liquid-only clouds with stable stratification, hence insignificant in-cloud mixing, which occur in low-aerosol conditions. IFS model fails to reproduce the cloud-surface decoupling observed during ASCOS. A new prognostic cloud physics scheme in IFS improves simulation of mixed-phase clouds, but does not improve the warm bias in the model, mostly because IFS fails to disperse low surface-warming clouds when observations indicate cloud-free conditions. With increasing summer open-water areas in a warming Arctic, there is a growing interest in processes related to the ice marginal zones and the summer-to-autumn seasonal transition. ACSE included measurements over both open-water and sea-ice surfaces, during melt and early freeze. The seasonal transition was abrupt, not gradual as would have been expected if it was primarily driven by the gradual changes in net solar radiation. After the transition, the ocean surface remained warmer than the atmosphere, enhancing surface cooling and facilitating sea-ice formation. Observations in melt season showed distinct differences in atmospheric structure between the two surface types; during freeze-up these largely disappear. In summer, large-scale advection of warm and moist air over melting sea ice had large impacts on atmospheric stability and the surface. This is explored with an LES; results indicate that while vertical structure of the lowest atmosphere is primarily sensitive to heat advection, cloud formation, which is of great importance to the surface energy budget, is primarily sensitive to moisture advection. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>
239

A short range radio telemetry system for Arctic acoustic experiments

Wales, Carl Alzen January 1982 (has links)
Thesis (Ocean E)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by Carl Alzen Wales. / Ocean E
240

Underwater acoustic ambient noise in the Arctic

Chen, Yie-Ming January 1982 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by Yie-Ming Chen. / M.S.

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