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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.
121

A comparison of ice drift motion from modeled and buoy data

Lundeen, Gregory N. January 1990 (has links) (PDF)
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, December 1990. / Thesis Advisor(s): Bourke, Robert H. ; Morison, James. "December 1990." Description based on title screen as viewed on April 1, 2010. DTIC Identifier(s): Buoys, Sea Ice, Arctic Buoys, Ice Forecast, Arctic, Theses. Author(s) subject terms: PIPS, Sea Ice, Arctic Buoys, Ice Forecast, Arctic. Includes bibliographical references (p. 106-111). Also available in print.
122

Wireless Local Loop in Developing Regions: Is It Too Soon For Data?

Kibati, Mugo, Krairit, Donya January 1999 (has links)
No description available.
123

Rusko - strategický trh pro české podnikatele / Russia - Strategic market for czech companies

Rakušan, Lukáš January 2007 (has links)
The thesis contains the analysis of the Russian market potential for Czech companies from the economic development, sectoral possibilities and opportunities offered by Russian Federal Subjects point of view. The paper discuss also the Russian economic development in the 90's and mutual Czech and Russia economic relationships and cooperation.
124

On the thermal nature and sensing of snow-covered arctic terrain.

Poulin, Ambrose O. January 1972 (has links)
No description available.
125

Diversity, distribution and feeding habits of North American arctic soil Acari.

Behan, Valerie January 1978 (has links)
No description available.
126

Molecular phylogeography of Dryas integrifolia : glacial refugia and postglacial recolonization

Tremblay, Nicolas-Olivier R. January 1997 (has links)
This thesis addresses the consequences of the last glaciation on the distribution and genetic diversity of arctic flora. The principal aim is to infer the full-glacial and postglacial migrational history of Dryas integrifolia M. Vahl. (Rosaceae) from the intraspecific phylogeny of cpDNA haplotypes along with pollen and macrofossil distribution data. The results suggest that four refugia existed during the last glaciation and that each served as significant sources of recolonization when the ice retreated. The two most important refugia are located in the northwestern Arctic (Beringia and the High Arctic), with two other refugia located southeast of the ice sheet and along the coastal regions of the eastern Arctic. High genetic substructure among populations is likely attributable to past vicariance and recent recolonization events, whereas high local diversity is probably indicative of recolonization from several sources and high gene flow in recent time.
127

Upper atmosphere dynamics in the auroral zone / by Georgina D. Price

Price, Georgina D. January 1988 (has links)
Bibliography: leaves 117-130 / xii, 130 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1989
128

Phytoplankton ecology in a high arctic polynya

Butler, Joanne Elizabeth January 1985 (has links)
Primary production was studied in Fram Sound, part of the Hell Gate-Cardigan Strait polynya, from June to August, 1982. Primary production rates, phytoplankton biomass (chlorophyll α), and water transparency were measured and used in conjunction with modelled solar radiation values to numerically model primary production during this time. The major phytoplankton nutrients were also measured. Early season chlorophyll α concentrations were low, and the increased light availability due to reduced ice cover in this area did not appear to enhance early season production. Chlorophyll concentrations peaked twice; the first peak occured on 20 July and the second on 14 August. The mean primary production rate and phytoplankton biomass were 998 mg C.m⁻² .d⁻¹ and 72 mg chl.m⁻² . This production rate is higher than that measured in other High Arctic areas. Nitrogen, phosphorus and silica were essentially homogeneously distributed during the sampling period and these concentrations varied little from June to August except during 5 days in late August, when they decreased by half then returned to previous levels. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
129

Molecular phylogeography of Dryas integrifolia : glacial refugia and postglacial recolonization

Tremblay, Nicolas-Olivier R. January 1997 (has links)
No description available.
130

Solar influences on Polar ozone.

Stephenson, Judy Ann Elizabeth. January 1994 (has links)
Measurements by the TOMS instrument aboard the Nimbus 7 satellite, of total column ozone over polar regions have been studied to determine the effects of solar induced natural ozone modulation. Two different analysis methods were employed to ascertain short term (days to months) and long term (months to years) solar influences on polar ozone. Bursts of intense solar activity can result in solar proton events (SPE's). The high energy protons, originating in solar flares, produce secondary electrons which can generate large concentrations of odd nitrogen in the middle atmosphere. These reactive species can catalytically destroy ozone. Three case studies are presented in an attempt to quantify the effect of SPE's on ozone mass over a latitude region 90 to 70°. In order to monitor the ozone response following a SPE over both hemispheres simultaneously, the SPE must occur during the equinox period when both poles are irradiated. Fortuitously, a SPE was recorded in March 1989, the analysis of which forms a case study in this thesis. Ozone depletions of 7.4 x 10 to the power of 9 kg for the south polar cap and 8.0 x 10 to the power of 9 kg for the north polar cap indicate the degree of symmetry for this event. Longer term effects of solar variability are investigated by Fourier techniques. A Fourier transform of eleven years of total ozone mass values, over the region 90 to 70° S, was performed. Inspection of the Fourier spectrum reveals peaks associated with solar cycle, annual and semi-annual oscillations, that may be attributed directly to solar variation. Other peaks, corresponding to QBO and ENSO periodicities, may be ascribed to indirect solar influences i.e. thermally driven dynamics. Finally, a comparison between the phase of the solar cycle peak in this spectrum with that in a spectrum of daily values of solar radio flux, reveals that the austral polar ozone solar cycle periodicity lags solar forcing by 2.8 years. Portions of chapters have been reported at the 1990 South African Institute of Physics Annual Conference, University of Port Elizabeth, South Africa and as a poster at the 1992 Quadrennial Ozone Symposium, Charlottesville, United States of America, 4-13 June 1992. In addition, various parts of this work has been submitted for publication, viz: Stephenson, J. A. E. and M. W. J. Scourfield, Importance of energetic solar protons in ozone depletion, Nature, 352, 137: 1991. / Thesis (Ph.D.)-University of Natal, Durban, 1994.

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