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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.
21

Reproduction and distribution in Arctic Gasterosteus Aculeatus L. : teleostei, gasterosteidae.

Freeman, Milton M. R. January 1965 (has links)
This study is ecological in objective; primarily it attempts to evaluate environmental factors limiting the distribution of a wide-ranging species of fish, Gasterosteus aculeatus, in one sector of its holarctic range. Two approaches to this investigation are made: comparative and deductive. The comparative method is possible because many studies have been made on temperate-zone populations of the species; modified behaviour observed in the present study are consequently viewed as probably adaptive to the different environmental conditions of the north. [...]
22

High latitude coupled sea-ice-air thermodynamics /

Swick, William A. January 2004 (has links) (PDF)
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, Sept. 2004. / Thesis advisor(s): Roland W. Garwood. Includes bibliographical references (p. 71-73). Also available online.
23

Late Pliocene-early Pleistocene paleoclimatology of the Arctic Ocean

Chern, Laura Allison. January 1984 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 70-78).
24

The distribution of dissolved cadmium in the Canadian Arctic Ocean

Jackson, Sarah 22 December 2017 (has links)
The biogeochemical cycling of oceanic dissolved cadmium (dCd) has been an active area of research for the past ~40 years, due in part to the close correlation with phosphate (PO4). The global Cd:PO4 relationship has led to the use of microfossil Cd/Ca as a paleoproxy for ocean circulation and nutrient utilization; however considerable spatial and temporal variability in the relationship - particularly in surface waters - limits the utility of the proxy. Understanding the global biogeochemical cycling of Cd is an active area of research; however the Arctic Ocean is largely omitted from global models due to lack of data. This work presents depth profiles of dCd and Cd/PO4 ratios from 18 individual stations in the Canadian Arctic, collected during the Canadian GEOTRACES cruises GN02 and GN03, which connect the Arctic Ocean to the North Atlantic through the Canadian Arctic Archipelago (CAA). Salinity-driven water mass stratification exerts a primary control on the spatial distribution of Cd in the region, with elevated dCd and high Cd/PO4 ratios (~0.37 pM/μM) associated with waters of Pacific-origin. The elevated dCd and Cd/PO4 ratios are used as a tracer of Pacific-origin waters, identifying the presence of Pacific-origin water through the CAA and into Baffin Bay. High surface Cd/PO4 ratios were observed across the transect, consistent with a general global increase in surface water Cd/PO4 with increasing latitude. The analysis of Cd and other bioactive trace metals (Mn, Fe, Ni, Cu, Zn and Pb) still presents considerable analytical challenges due to the high-risks of contamination, low concentrations and complex matrices. I present a novel multi-element analytical method, which combines the commercially-available seaFAST pico preconcentration system with ICP-MS/MS analysis. In this work, we demonstrate that ICP-MS/MS, which combines two mass-selecting quadrupoles separated by an octopole collision/reaction cell, effectively removes common interferences (ArO+ on 56Fe and MoO+ on Cd) when pressurized with O2 gas. Accurate and precise measurements of iv the consensus references standards SAFe S and SAFe D and the certified reference material NASS-6 are presented as validation of the method. This thesis presents a novel method for the analysis of trace / Graduate
25

Planetary waves in a polar ocean

LeBlond, Paul Henri January 1964 (has links)
The dynamics of the Arctic ocean are studied on a polar projection of the sphere. The density structure is idealized as a two-layer system, and a general formulation is developed which allows inclusion of latitudinal and longitudinal depth variations as well as asymmetries in the boundaries of the ocean. For simplicity, the density structure is neglected when depth variations are present. Time dependent displacements from equilibrium levels are assumed to be waves of constant zonal wave number; no radial propagation is considered. Amplitude equations are derived for these displacements, subject to the assumption that the polar basin is small enough to keep only a first approximation to the curvature of the Earth. A semi-qualitative investigation of the possible solutions is made in the case of a symmetrical basin, using the Method of Signatures, and existence criteria are found for the solutions in the presence of radial depth variations. Concentrating thereafter on planetary waves, explicit solution for such motions in the simplest case (depth constant, symmetrical boundaries) allows comparison with the results of other investigators (Longuet-Higgins, 1964 b; Goldsbrough, 1914 a) . It is found that the polar projection and first approximation to the curvature give quite good results, so that this method may be applied to polar regions in the same way as the β-plane is used in mid-latitudes. The general effects of radial bottom slopes are discussed and a simple example treated more explicitly. Some theorems of Ball (1963) on the motions of shallow rotating fluids in paraboloidal basins are found to hold for such basins in the polar plane approximation to the sphere. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
26

Reproduction and distribution in Arctic Gasterosteus Aculeatus L. : teleostei, gasterosteidae.

Freeman, Milton M. R. January 1965 (has links)
No description available.
27

A short range radio telemetry system for Arctic acoustic experiments

Wales, Carl Alzen January 1982 (has links)
Thesis (Ocean E)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by Carl Alzen Wales. / Ocean E
28

Underwater acoustic ambient noise in the Arctic

Chen, Yie-Ming January 1982 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by Yie-Ming Chen. / M.S.
29

Zooplankton distribution in the Arctic Ocean with notes on life cycles

Harding, Gareth C. H. January 1966 (has links)
During the Norwegian North Polar Expedition of 1893-96, the historie voyage of the Fram ( Sars, G.O. 1900), the first zooplankton collections were taken from the Arctic Basin. In 1931 the Nautilus made collections north of Spitzbergen, being the first submarine to attempt polar research (Farran, 1936). [...]
30

Acute effects of petroleum hydrocarbons on the arctic littoral mysid, mysis oculata (Fabricius)

Riebel, Philippe N. January 1988 (has links)
No description available.

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