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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.
201

Observations and modeling of ice jam release events on the Hay River, NWT

Watson, David 06 1900 (has links)
The Town of Hay River experiences significant threats to life and property each spring as ice jam release events from upstream bring waves of ice and water to the town. The development of a forecasting tool for ice jam release events has been limited by insufficient data, especially regarding the speed of ice runs associated with ice jam release events. The purpose of this research was to document and analyze ice jam release events to provide the town warning of their potential timing and magnitude, and to contribute to general knowledge on ice jam release. Comprehensive field programs were undertaken from 2007 to 2009, and this new data was used to assess the River1D ice jam release forecasting model. Although the model showed reasonable approximations for wave arrival times for flood forecasting purposes, the predicted speeds and arrival times of ice runs did not agree very well with field observations. / Water Resources Engineering
202

Summertime surface mass balance and atmospheric processes on the McMurdo Ice Shelf, Antarctica.

Clendon, Penelope Catherine January 2009 (has links)
The aim of this research was to demonstrate the relationship between variations in summertime surface mass balance of the McMurdo Ice Shelf and atmospheric processes. The approach encompassed a broad range of techniques. An existing energy balance mass balance model was adapted to deal with debris-covered ice surfaces and modified to produce distributed output. Point based surface energy and mass balance for two key surfaces of the ice shelf were linked to different synoptic types that were identified using a manual synoptic classification. The distributed model was initialised with distributed parameters derived from satellite remote sensing and forced with data from a regional climate model. Patterns of summertime surface mass balance produced by the distributed model were assessed against stake measurements and with respect to atmospheric processes. During the summers of 2003-2004 and 2004-2005 an automatic weather station (AWS) was operated on bare and debris-covered ice surfaces of the McMurdo Ice shelf, Antarctica. Surface mass balance was calculated using the energy balance model driven by the data from the AWS and additional data from permanent climate stations. Net mass balance for the measurement period was reproduced reasonably well when validated against directly measured turbulent fluxes, stake measurements, and continuously measured surface height at the AWS. For the bare ice surface net radiation provided the major energy input for ablation, whereas sensible heat flux was a second heat source. Ablation was by both melt (70%) and sublimation (30%). At the debris-covered ice site investigated, it is inferred that the debris cover is sufficient to insulate the underlying ice from ablation. Synoptic weather situations were analysed based on AVHRR composite images and surface pressure charts. Three distinct synoptic situations were found to occur during the summers, these were defined as Type A, low pressure system residing in the Ross Sea Embayment; Type B, anticyclonic conditions across region; and Type C, a trough of low pressure extending into the Ross Sea Embayment. A dependence of surface energy fluxes and mass balance on synoptic situation was identified for the bare ice surface. The distributed model was found to produce spatial patterns of mass balance which compared well with stake measurements. Mass balance patterns show that the McMurdo Ice Shelf was generally ablating in the west, and accumulating in the east during summer. Areas of enhanced ablation were found which were likely to be caused by the surface conditions and topographic effects on the wind field. The mean summertime surface mass balance across the entire ice shelf for the 2003-2004 and 2004-2005 summers were –2.5 mm w.e. and –6.7 mm w.e. respectively. The differences between the two summers are inferred to be a result of more frequent type A conditions occurring during the summer of 2004-2005.
203

Beobachtung und Modellierung der Schneeschmelze und Aufeisbildung auf arktischem und antarktischem Meereis = Observation and modelling of snow melt and superimposed ice formation on Arctic and Antarctic sea ice /

Nicolaus, Marcel. January 2006 (has links) (PDF)
Univ., Diss.--Bremen, 2006. / Richtiger Name des Verf.: Nicolaus, Marcel.
204

Ice shedding from cables and conductors : a cracking model of atmospheric ice = Délestage de glace des câbles et des conducteurs : un modèle de rupture fragile de la glace atmosphérique /

Kermani Koosheh, Majid, January 2007 (has links)
Thèse (D.Eng.) -- Université du Québec à Chicoutimi, 2007. / La p. de t. porte en outre: Thèse présentée à l'Université du Québec à Chicoutimi comme exigence partielle au doctorat en ingénierie. CaQQUQ Bibliogr.: f. [211]-220. Document électronique également accessible en format PDF. CaQQUQ
205

Numerical and experimental studies of the mechanical behaviour at the ice/aluminium interface = Études numérique et expérimentale du comportement mécanique à l'interface glace/aluminium /

Matbou Riahi, Mehran, January 2007 (has links)
Thèse (M.Eng.) -- Université du Québec à Chicoutimi, 2007. / La p. de t. porte en outre: Mémoire présenté à l'Université du Québec à Chicoutimi comme exigence partielle de la maîtrise en ingénierie. CaQCU Bibliogr.: f. 137-143. Document électronique également accessible en format PDF. CaQCU
206

A new method for melt detection on Antarctic ice-shelves and scatterometer calibration verification /

Kunz, Lukas Brad, January 2004 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2004. / Includes bibliographical references (p. 111-113).
207

The design, manufacture and verification of a high capacity force and moment measurement system /

Tucker, John R., January 1998 (has links)
Thesis (M. Eng.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 73-74.
208

Damage and microstructural change in laboratory grown ice under high pressure zone conditions /

Melanson, Paul M., January 1998 (has links)
Thesis (M. Eng.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 125-129.
209

Transient behavior of the West Antarctic ice streams implications for global sea-level changes and ocean circulation /

Bougamont, Marion. January 2003 (has links)
Thesis (Ph. D.)--University of California, Santa Cruz, 2003. / Typescript. Includes bibliographical references (leaves 115-128).
210

Dynamics of the coupled ice-ocean system in the marginal ice zone study of the mesoscale processes and of constitutive equations for sea ice /

Häkkinen, Sirpa. January 1984 (has links)
Thesis (Ph. D.)--Florida State University, 1984. / Typescript. Includes bibliographical references (leaves 91-95).

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