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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.
91

An Investigation of Active Microwave Remote Sensing of Summer Sea Ice in the Western Canadian Arctic

Warner, Kerri 18 December 2012 (has links)
Active microwave remote sensing is an important tool for classification of sea ice in polar regions. The aim of this research is to improve the understanding of microwave scattering that occurs during the advanced melt season, with a focus on multiyear ice (MYI). This was done using a combination of in situ C-Band scatterometer measurements, geophysical characteristics of ice, and Radarsat-2 data. Results indicate that it is difficult to differentiate between first year ice (FYI) and MYI during advanced melt but combinations of incidence angle and polarization exist that assist with this. It is known that the presence of liquid water governs microwave scattering, therefore further research investigating the variation of microwave backscattered signatures over a diurnal time period was conducted. These results indicate an inverse relationship between temperatures and microwave signatures. The overall results from this research show that summer MYI signatures are extremely variable and difficult to classify.
92

Idealised models of sea ice thickness dynamics

Godlovitch, Daniel 10 September 2013 (has links)
Thickness distributions of sea ice (g(h)) display a ubiquitous exponential decay (’tail’) in ice above approximately 2 meters thick. This work uses idealised models to examine the root causes of the exponential tail of the sea ice thickness distribution. The ice of thickness greater than 2 meters is formed through the fracture and piling of ice caused by interactions between floes, driven by winds and currents. The material properties of sea ice are complex and mathematical descriptions of the relationship between force and deformation of a floe are still a topic of study. Smoluchowski Coagulation Models (SCMs) are used to develop an abstract representation of redistribution dynamics. SCMs describe populations whose members of fixed size combine at size-dependent rates. SCMs naturally produce exponential or quasi-exponential distributions. An SCM coupled with a thermodynamic component produces qualitatively realistic g(h) under a wide range of conditions. Using the abstract representation of redistribution dynamics from SCMs, a model developed from physical processes specific to sea ice is introduced. Redistribution events occur at rates dependent on the change in potential energy. This model is demonstrated to produce qualitatively realistic g(h). Sensitivity analysis shows that primary model sensitivities are to the relative strengths of the dynamic and thermodynamic components of the model; and to the relative occurrence of ice ridging, shearing and rafting. The exact relationship between the rate of redistribution events and the energy they consume is shown to be of lesser importance. We conclude that the exponential tail of g(h) is a mathematical consequence of the coagulative nature of the ice thickness redistribution process, rather than the material properties of sea ice. These model results suggest the strongest controls on the form of the tail are the relative strengths of thermodynamic and dynamic action, and the relative occurrence of ice ridging, shearing and rafting. / Graduate / 0415 / 0768
93

Ice drift in the Gulf of St. Lawrence.

Ingram, Richard Grant, 1945- January 1967 (has links)
No description available.
94

A thermodynamic and dynamic Lagrangian model for icebergs a data-model intercomparison for the Southern Ocean /

Abrahamowicz, Maria. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Atmospheric and Oceanic Sciences. Title from title page of PDF (viewed 2008/05/13). Includes bibliographical references.
95

A model study of natural variability in the Arctic climate /

Bitz, Cecilia M. January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [191]-199).
96

Relationships between Arctic summer sea-ice area and the subsequent winter North Atlantic Oscillation

Chan, Weihan. January 2008 (has links)
Thesis (M.S.)--University of Delaware, 2008. / Principal faculty advisor: Daniel J. Leathers, Dept. of Geography. Includes bibliographical references.
97

Modeling the Arctic sea-ice cover from the early Holocene

Dyck, Sarah E., January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Atmospheric and Oceanic Sciences. Title from title page of PDF (viewed 2009/06/23). Includes bibliographical references.
98

Surface and airborne infrared detection of sea ice hazards /

Worsfold, Richard D. January 1981 (has links)
Thesis (M.Eng.) -- Memorial University of Newfoundland, 1982. / Bibliography : leaves 116-119. Also available online.
99

Fracture toughness of fresh water ice and saline ice /

Azadeh-Tehrany, Ali-Reza. January 1983 (has links)
Thesis (M. Eng.) -- Memorial University of Newfoundland, 1984. / Bibliography : leaves 28-30. Also available online.
100

Development of a first-year ridge keel load model /

Bruneau, Stephen Earl, January 1996 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 1997. / Restricted until May 1999. Bibliography: leaves 266-276.

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