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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

Seasonal variation of wind gustiness in a portion of the Columbia Gorge

Baker, Robert W. 16 June 1976 (has links)
The seasonal variation of wind speed fluctuations is studied at four locations in The Dalles area of the Columbia River Gorge. Three of the sites are located in or near the valley floor while the fourth site is on top of a 900 m (3000 ft) ridge just north of The Dalles. The speed fluctuations or gustiness at these sites varies with terrain roughness, wind speed, and atmospheric stability. Due to the channelling effects of the Gorge, wind flow in The Dalles area is predominantly upriver or downriver. Strongest winds occur from the west at all four of the sites that were analyzed. Highest gustiness values occurred at the Martin Marietta site located near the rugged foothills of the eastern slopes of the Cascade Mountain Range. Moderate gustiness values were common at KCIV located on the top of the ridge north of The Dalles and at the D.C. Test Site surrounded by rolling hills. Smoothest flow was found along the relatively level valley floor at The Dalles Dam. Gustiness in relation to wind speed varied at all four sites. Gustiness values increased with speed through the moderate speed range at KCIV while gustiness decreased with speed at The Dalles Dam and the Martin Marietta site. No distinct relationship was found at the D.C. Test Site. At KCIV changes in gustiness are directly related to the amount of solar insolation and hence the atmospheric stability. Gustiness values were highest during the summer and daytime values were greater than those at night during both winter and summer. In contrast, at the other three sites near or on the valley floor no distinct relationship between the stability variations and the changes in gustiness could be found. Results indicated that the gustiness values during the winter at these three locations exceeded those during the summer. It appears that the unstable nature of the post frontal wintertime air mass is responsible for the strong and turbulent northwest flow. Although moderate speed fluctuations were common at KCIV, this site is the most appealing of the four locations for wind power generation due to the persistency of moderately strong winds during both summer and winter. Least attractive of the four sites is Martin Marietta where high gustiness values along with weak winter winds provide little usable wind energy. / Graduation date: 1977
32

Utilization of the Columbia River Estuary by American shad, Alosa sapidissima (Wilson) /

Hammann, Mark Gregory. January 1981 (has links)
Thesis (M.S.)--Oregon State University, 1982. / Typescript (photocopy). Includes bibliographical references (leaves 37-40). Also available on the World Wide Web.
33

An examination of the form and variability of manganese oxide in Columbia River suspended material /

Covert, Paul Allister. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 62-64). Also available on the World Wide Web.
34

Annual cycles of organic matter and phytoplankton attributes in the Columbia and Willamette Rivers, with reference to the Columbia River Estuary

Sullivan, Barbara Elaine 25 February 1997 (has links)
Graduation date: 1997
35

Annual secondary production and community dynamics of benthic infauna in a Columbia River estuary mudflat

Jones, Kim K. 19 July 1983 (has links)
Graduation date: 1984
36

Enabling technologies for fast, nonlinear data assimilation in a coastal margin observatory /

Frolov, Sergey. January 2007 (has links)
Thesis (Ph.D.) OGI School of Science & Engineering at OHSU, November 2007. / Includes bibliographical references.
37

Ichthyoplankton of the Lower Columbia River Estuary in relation to environmental variables

Marko, Lisa Marie, January 2008 (has links) (PDF)
Thesis (M.S. in environmental science)--Washington State University, August 2008. / Includes bibliographical references (p. 42-45).
38

Historical alterations to the Columbia River Gorge as a result of transportation infrastructure, 1850-1900 /

Daniel, Isaac B. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes folded map. Includes bibliographical references (leaves 101-110). Also available via the World Wide Web.
39

The stratigraphic relationships of the Columbia River Basalt Group in the lower Columbia River Gorge of Oregon and Washington

Tolan, Terry Leo 01 January 1982 (has links)
The purpose of this study was to produce a detailed geologic map of the CRBG in the western portion of the Columbia River Gorge (fig. 1). The objectives were (1) to identify and delineate the extent of the Priest Rapids Member and Pomona Member intracanyon flows, and (2) to define the relationship of post-CRBG units to the CRBG intracanyon flows.
40

The Columbia River as a Barrier to Gene Flow in the Vagrant Shrew, Sorex vagrans vagrans Baird

Kirk, James J. 24 November 1976 (has links)
Twenty--one morphological characters were measured in shrews from four islands in the Columbia River and from the adjacent Oregon and Washington shores. Information on the history and characteristics of the river islands was gathered to facilitate interpretation of the shrew’s morphology data. Significant differences between character means of different populations were detected and average taxonomic distances between pairs of populations were calculated. The Columbia River is an incomplete barrier to gene flow, but its influence has been sufficient to allow divergence of island populations. Natural selection on the small gene pools of island populations has probably contributed to the divergence. Shrews most likely reached the islands from the mainlands by rafting on floating vegetation and debris. Morphometric comparison of island populations seems to provide a more sensitive indication of restricted gene flow than similar comparison of opposite mainland populations.

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