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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.
11

Computer analysis of the surface current field off Oregon based on drift bottle data

Lung, Hu Ernest 30 April 1973 (has links)
The fall-winter surface current field off Oregon was determined by analysis of ten years of drift bottle data. Computer programs were developed for generating bottle tracks on a numerical grid, for interpolating bottle velocity components to fill void grid points and for smoothing irregularities in the velocity fields. Charts are presented showing the spatial distribution of surface currents determined in the study area of 5° latitude by 2-1/2° longitude. The mean currents for the fall-winter season have a predominantly northerly flow with speeds increasing from the south to the north (from 0.01 to 0.35 knots). This probably is a consequence of the increase in speed of southerly winds from south to north in the study area during the fall-winter season. The northly flow in October during the years 1961-70, when compared with the dominant southerly flow during this month from measurements prior to 1935, may indicate a major change of Davidson-California Current System within the past forty years. Apparent onshore flow may be introduced by bottle diffusion; this flow is prominant at all latitudes along which bottle releases are concentrated. An offshore flow component north of 46°30'N may be related to the Columbia River discharge and the westward extension of land. / Graduation date: 1973
12

Temperature finestructure and microstructure observations in the coastal upwelling region off Oregon during the summer of 1974

Marmorino, G. O. 12 November 1976 (has links)
Graduation date: 1977
13

Life-history organization of herring (Clupea harengus pallasi) in the northeast Pacific

Aleaziz, Farzad 14 November 1996 (has links)
The distribution of herring (Clupea harengus pallasi) in the Northeast Pacific extends from southern California to northern Alaska. Studies on variation in herring life-history are limited to local characteristics and recruitment populations or relatively restricted regions of the Northeast Pacific. In this study I assessed herring life-history patterns and recruitment variation among 14 sites extending from Lynn Channel in Alaska to San Francisco Bay in California. Biological data were compiled from published and of state and provincial unpublished technical reports fisheries agencies in the northeast Pacific. Multivariate (PCA) and inferential statistical methods were applied in data analysis. Ordinations of length-and weight-at-age revealed no latitudinal patterns among the 14 herring sites. Among four sites for which environmental data were available, there were significant negative correlations between first PC scores of size and Ekman layer transport and sea-surface salinity (SSS). Reproductive characteristics of herring appeared to vary latitudinally. Herring from the more southerly sites tended to mature at an earlier age and smaller size and have a longer duration of spawning than herring from northerly sites. There were significant negative first PC scores of reproductive correlations between variables and Ekman transport, sea-surface temperature, and SSS. With the exception of Lynn and Seymour Channels in Alaska, the most northerly sites in this study, asymptotic to northern size (L[subscript]���) tended to increase from southern latitudes. With the exception of southern Strait of Georgia (British Columbia) herring and Tomales Bay (California) herring, growth coefficients (K) appeared to be higher in latitudes. L[subscript]��� was negatively correlated with SST. Recruitment variation at three sites was related to Ekman layer transport during the periods of spawning. At San Francisco Bay recruitment was negatively related to winter Ekman transport. At Sitka and Island, recruitment showed a southwestern Vancouver significant positive and negative correlation, respectively, Recruitment in northern and with spring Ekman transport. southern Strait of Georgia were negatively correlated with SST during fall. There was no correlation between recruitment and SSS for all sites. / Graduation date: 1997
14

The response of Oregon shelf waters to wind fluctuations : differences and the transition between winter and summer

Sobey, Edwin J. C., 1948- 15 February 1977 (has links)
The physical characteristics of continental shelf waters off Oregon during late winter and spring of 1975 are described and compared with observations taken previously during summer. The currents in winter are barotropic in the monthly means while in summer the currents are baroclinic. Alongshore current fluctuations on the time scale of a few days are depth dependent in winter but become depth independent in summer. The current shear changes sign on the several day time scale in winter while in summer the deeper currents are always northward with respect to the near surface currents. Alongshore coherences of sea level and currents indicate that winter fluctuations generally propagate southward rather than northward as previously observed in summer. These winter fluctuations in alongshore currents also have onshore/offshore phase speeds that are comparable in magnitude to their alongshore phase speeds. There is no evidence for free continental shelf wave activity in winter although forced waves (travelling predominately southward, as do the meteorological disturbances) may exist. The Gill and Schumann (1974) model, which predicts sea level from a knowledge of the alongshore components of winds along the coastline, is tested for winter and summer in 1975 and found to have some predictive ability for fluctuations on the time scale of several days. The transition from winter to summer is initiated in a dramatic barotropic event and continues as a longer period baroclinic adjustment. The former is marked by a sudden reversal of currents and a lowering of sea level while the latter is marked by a slow rising of the pycnocline and with it the layer of maximum vertical shear. Both the barotropic changes at the transition event and the adjustment of the density field, which occurs after the transition event, are directly forced by the local wind. / Graduation date: 1977
15

Geopotential anomaly and geostrophic flow off Newport, Oregon

Lee, Kuo-heng 25 April 1967 (has links)
The geopotential anomalies and the average meridional geostrophic flow off Newport, Oregon, were computed from the data taken during twenty-one hydrographic cruises. The annual average of geopotential anomaly was 1.31 dynamic meters with a seasonal variation of the order of 14 dynamic centimeters. Highest values of geopotential anomaly occurred in September; lowest values occurred in April. Both the highest and lowest value of geopotential anomaly occurred at 105 nautical miles offshore. The currents found by dynamic computation were weak and irregular, generally 5 cm/sec or less. The direction of the average meridional geostrophic flow varied with season. Within 105 nautical miles of the coast, flow was southward in summer, northward in winter. Beyond 105 nautical miles from the coast, flow directions reversed, that is, flow was northward in summer and southward in winter. / Graduation date: 1967
16

Baroclinic instabilities of nonzonal ocean currents with application to the Kuroshio Extension Current

Yun, Jae-Yul January 1986 (has links)
Typescript. / Bibliography: leaves 144-147. / Photocopy. / xvi, 147 leaves ill
17

Nitrogen fixation rates and controls at station ALOHA

Grabowski, Marcie N.W January 2005 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 48-54). / vii, 54 leaves, bound ill. 29 cm
18

Effects of nutrient enrichment and mesoscale eddies on metabolic balance in the subtropical North Pacific Ocean

McAndrew, Patricia M January 2006 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 71-81). / vi, 81 leaves, bound ill., map 29 cm
19

Cascadia channel : the anatomy of a deep-sea channel

Griggs, Gary B. 08 November 1968 (has links)
Graduation date: 1969
20

Paleomagnetic inclination shallowing in deep-sea sediments

Arason, Pórdur 18 April 1991 (has links)
In this thesis anomalous downcore shallowing of paleomagnetic inclinations is interpreted to be caused by sediment compaction. Thus, compaction-induced inclination shallowing may influence tectonic reconstructions that are based on inclinations from deep-sea sediment cores. Progressive downcore shallowing of the remanent inclination was observed in a 120-m section of Plio- Pleistocene sediments at Deep Sea Drilling Project (DSDP) site 578 in the northwest Pacific. Near the top of the section the average inclination corresponds to the expected geocentric axial dipole value of 53° but shallows downcore by about 6° to 8°. In sediments spanning the same time interval of neighboring site 576, no inclination shallowing was observed. This second site has considerably lower sedimentation rates, and the Plio- Pleistocene is represented by a 26-m sedimentary section. The inclination shallowing at site 578 was correlated to a downhole decrease in porosity, and these results are interpreted to suggest that both the downhole inclination shallowing and decrease of porosity in site 578 were caused by sediment compaction. Microscopic models demonstrate that sediment compaction may lead to inclination shallowing of the magnetic remanence. Furthermore, it is shown that inherent initial within-sample dispersion of the magnetic moments will transform any form of microscopic mechanism to an equation of a standardized form: tan (I-ΔI) = (1-a ΔV) tan I, where I is the inclination of the ambient field, ΔI is the inclination shallowing, a is a constant and ΔV the compaction. Paleomagnetic inclinations of Cretaceous DSDP sediments from the Pacific plate are known to be systematically shallower than predicted from paleolatitudes of hot spot reconstructions. Published paleomagnetic data were reexamined and the shallow Cretaceous inclinations explained as a result of sediment compaction. The Cretaceous data are used to estimate the parameter a. The resulting a values are comparable to those of previous studies of compaction-induced inclination shallowing, both from laboratory experiments and the considerably younger deep-sea sediments at site 578. Values of the parameter a suggest that it might be controlled by sediment lithology with greater shallowing for clayey than calcareous sediments. / Graduation date: 1991

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