Record Details
Heat unit accumulation in degree-hours above selected temperature levels in Oregon
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Heat unit accumulation in degree-hours above selected temperature levels in Oregon |
| Names |
Newland, Dale Cecil
(creator) Rudd, Robert D. (advisor) |
| Date Issued | 1961-06-08 (iso8601) |
| Note | Graduation date: 1964 |
| Abstract | The heat unit concept of time-temperature relationships is used in this thesis as a means of studying the temperature element of the climate at nine Oregon stations. The stations, Astoria, Baker, Burns, Eugene, Medford, Pendleton, Portland, Roseburg, and Salem, were selected on the basis of distribution and availability of Weather Bureau data. One table of average daily heat unit totals was compiled for each of five selected threshold temperatures, 30°, 35°, 40°, 45°, and 50°F, for each of the nine stations. The method of heat unit computation devised by Lindsey and Newman was considered the best adapted to the aims of this study. An average daily heat unit graph and an annual accumulation graph were prepared for each of the stations. In an effort to note similarities and/or differences in heat unit occurrences in the several parts of Oregon, the following aspects were considered: time of occurrence of maxima and minima, range between maxima and minima, rates of change of heat unit occurrence, rates of heat unit accumulation, and annual heat unit totals. Astoria has the greatest seasonal lag of maxima after the summer solstice, approximately two months, while the remainder of the stations have lags of approximately one month. During the cool season, all stations exhibit a similar lag of about twenty days. Pendleton has the highest maxima at all threshold levels, while Medford has the next highest, followed by Burns, Baker, Portland and Salem, Roseburg, and Eugene, with Astoria having the lowest maxima at all thresholds, Astoria has the highest minima at the 30°F threshold and eastern Oregon stations have the lowest minima, with Roseburg, the Willamette Valley stations, and Medford being intermediate. Astoria has the smallest range between maxima and minima; the eastern Oregon stations have the greatest range. Ranges at Medford resemble those of the eastern Oregon stations, while Roseburg and the Willamette Valley stations have similar ranges between those for Astoria and the eastern Oregon stations. The eastern Oregon stations have the most rapid rate of increase in daily heat units in the spring and the most rapid rate of decrease in the fall. Astoria has the most gradual rate of change during these two periods, while the Willamette Valley stations are intermediate. Roseburg resembles Portland, Salem, and Eugene, while Medford is more similar to the eastern stations of Pendleton, Baker, and Burns. Pendleton, Medford, Baker, and Burns have the most rapid accumulation rates during the summer, the Willamette Valley stations and Roseburg have intermediate rates, and Astoria the least rapid rate during this period. During the cool season, however, the accumulation curves for Medford and the eastern Oregon stations are not as steep as the others. Medford has the greatest accumulated heat unit total at the 30°, 35°, and 40°F thresholds, with Pendleton having the greatest totals for the 45° and 50°F threshold levels. Baker has the lowest totals for the 30°, 35°, 40° and 45°F thresholds, and Astoria the lowest total for the 50°F threshold. |
| Genre | Thesis/Dissertation |
| Topic | Temperature |
| Identifier | http://hdl.handle.net/1957/48756 |
