Record Details
Field | Value |
---|---|
Title | Seasonal variation of wind gustiness in a portion of the Columbia Gorge |
Names |
Baker, Robert W.
(creator) Hewson, E. Wendell (advisor) |
Date Issued | 1976-06-16 (iso8601) |
Note | Graduation date: 1977 |
Abstract | 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. |
Genre | Thesis/Dissertation |
Topic | Winds -- Columbia River Gorge (Or. and Wash.) -- Measurement |
Identifier | http://hdl.handle.net/1957/28909 |