Record Details
Field | Value |
---|---|
Title | An investigation of high resolution dissolved oxygen profiles off the Oregon coast |
Names |
Jeter, Hewitt Webb
(creator) Mesecar, Roderick S. (advisor) |
Date Issued | 1972-08-09 (iso8601) |
Note | Graduation date: 1973 |
Abstract | Dissolved oxygen profiles made with an in situ polarographic device reveal structure in the form of inversions and gradient changes in the 100-600 meter depth zone off Oregon. Inversions 10-70 meters thick are traced over distances of 40 miles in some cases and are bracketed by a distance of 8 miles in others. The horizontal extent of these features agrees with observations of similarly-sized temperature and salinity structure reported by Stommel and Federov (1967) and by Hamon (1967). Oxygen maxima are correlated with changes in the vertical temperature gradient. Corresponding salinity minima are sometimes found. This relationship between properties is consistent with the formation of oxygen structure by a horizontal mixing process off Oregon. The existence of significant horizontal gradients in properties over distances of tens of miles favors the interleaving of dissimilar waters along density surfaces. A quantitative example of the horizontal mixing process yields temperature gradient changes near oxygen maxima similar to those observed. The in situ production of oxygen structure by layers of oxygen-consuming materials is considered unlikely in the size range studied. A transient state vertical model indicates that the consumption layers required for this mechanism are more intense than is consistent with recent biomass measurements. Diffusion calculations are used to model the decay of oxygen maxima. Calculated lifetimes range from 2.6 days for features 15 meters thick to 48.1 days for features 60 meters thick. These are considered estimates of the time scales associated with the stratification process. |
Genre | Thesis/Dissertation |
Topic | Seawater -- Composition |
Identifier | http://hdl.handle.net/1957/28405 |