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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.
31

The risks, management and adaptation to sea level rise and coastal erosion along the Southern and Eastern African Coastline.

Mather, Andrew Alan. 10 October 2013 (has links)
Sea level rise and coastal erosion are two processes which may result in major problems for coastal cities around the world. This is particularly true for Southern and Eastern African cities as they struggle to meet their developmental challenges in addition to sea level rise and coastal erosion. This thesis focuses on three main areas, the analysis of the rates of sea level from tide gauges in the region, the extent of wave run-up on the beach and the development of a simple technical and management framework that managers can apply to assess coastal hazards. The rates of sea level rise in the region vary, Zanzibar, Tanzania reflects a falling sea level at -3:64 plus minus 1:62 mm per year while the highest rate of sea level rise at Diego Garcia, British Indian Ocean Territories is +4:35 plus minus 7:61 mm per year. The rate of sea level rise are dependent on the complex interactions of vertical crustal movements, barometric pressure changes, and the warm Agulhas and cooler Benguela currents. Wave run-up is an indicator of the hazard zone. A number of international wave run-up models were assessed for use in this region and were found to be unsuitable. A new wave run-up model was developed which uses the bathymetric profile as opposed to the beach slope in predicting wave run-up. This model uses the equation Rx H0 = C S2=3, where Rx is the wave run-up height above Still Water Level, H0 is the significant wave height at the closure depth, C is dimensionless coefficient where median values are described by C ' 7:5, S is a representative nearshore slope (S = (hc=xh)). hc is the closure depth and xh the horizontal distance from the waters edge to the closure depth. An assessment of the impacts of sea level rise and wave run-up was undertaken based on a detailed case study of the Durban coastline. The results were incorporated into a standalone freeware viewer tool enabling this information to be accessible to planners, decision makers and the general public. The research has identifed several types of shoreline that are vulnerable to coastal erosion, sea level rise and extreme wave events. Recommendations as to what adaptation measures could be undertaken for the different beach types are proposed. With this information coastal managers and decision makers charged with managing shorelines can take the first step in understanding and adapting into the future. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2012.
32

Sea level rise and coastal erosion in the Hawaiian Islands

Jeon, Dongchull January 1995 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 181-188). / Microfiche. / xvii, 188 leaves, bound ill. 29 cm
33

Development of a mathematical N-line model for simulation of beach changes

Dang, Van To, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2006 (has links)
The development of a new N-Line model, which provides a practical tool for simulating regional beach changes induced by short and long-term processes, is described in this thesis. The new N-Line model consists of four main modules that together describe the hydrodynamic and morphological responses. The four constituent modules have been integrated based on a wide range of research including the utility and function of commercial or freeware models. They are RCPWAVE wave module, time-averaged and depth-integrated current module, sediment transport module based on Bailard (1981) and contour change morphological module. Two different time-scales and two staggered grid systems for hydrodynamic and morphological simulations were adopted alternatively. For short-term 2D profile changes, new N-Line model applicability has been examined using data from the laboratory to the field. For ideal beaches, new N-Line can simulate an offshore storm bar generation or an onshore accretion due to high or low energy waves. For SUPERTANK large-scale flume data, the predicted profile matched the measured profile well, especially the bar height and position. For beach profile data from the Gold Coast, storm-induced variations of barred profiles were reasonably modelled. The new N-Line model compared well with other commonly used cross-shore models such as SBEACH and UNIBEST. A new schematisation for a non-monotonic profile and DUNED inclusion were introduced. Sensitivity tests on cross-shore sediment coefficient (Kq), smoothing parameter (??s) and water level fluctuations were performed. For long-term 3D beach changes, the new N-Line model applicability has been tested with various boundary conditions using idealized and real field data. Two periods, 17 and 16 months, of beach changes before and after a major bypass plant commenced operation in 2001 at Letitia Spit were simulated. The profile and shoreline changes were predicted reasonably well. Empirical model parameters were determined after a range of sensitivity and calibration testing. The new N-Line model showed its better performance compared to one-line models. It can handle various boundary conditions, especially bypass conditions. The N-Line model is not only capable of modelling planform variations but also cross-shore profile changes.
34

Processes of sea-cliff erosion on the Oregon coast : from neotectonics to wave run-up /

Shih, Shyuer-ming. January 1992 (has links)
Thesis (Ph. D.)--Oregon State University, 1993. / Typescript (photocopy). Includes bibliographical references (leaves 123-129). Also available on the World Wide Web.
35

Three-dimensional modeling of coastal flows using unstructured grids /

Fortunato, Andre ́Bustorff, January 1996 (has links)
Thesis (Ph. D.)--Oregon Graduate Institute of Science & Technology, 1996.
36

Pocket beaches and longshore sediment transport Yellow Bank Beach, Santa Cruz County, California /

Scholar, Deirdre Claire. January 1998 (has links)
Thesis (M.S.)--University of California, Santa Cruz, 1998. / Typescript. Includes bibliographical references (leaves 76-78).
37

The changing shoreline of Surinam (South America)

Augustinus, P. G. E. F. January 1978 (has links)
Thesis--University of Utrecht, 1978. / Summary in Dutch. Bibliography: p. 223-232.
38

A field study of tide-induced sand movement on Del Monte Beach, California

Eubanks, Glen E. January 1968 (has links)
Thesis (M.S.)--Naval Postgraduate School, 1968. / Includes bibliographical references (leaves 53-54).
39

Effects of particle size and wave state on grain dispersion

Murray, Stephen Patrick. January 1966 (has links)
Thesis (Ph. D.)--University of Chicago, 1966. / "June 1966"--Cover. Includes bibliographical references (leaves 52-56).
40

Late quaternary sea-level lowstand environments and chronology of outer Saco Bay, Maine /

Lee, Kristen M. January 2006 (has links) (PDF)
Thesis (M.S.) in Earth Sciences--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 109-119).

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