• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 630
  • 59
  • 50
  • 50
  • 50
  • 50
  • 50
  • 47
  • 46
  • 31
  • 28
  • 13
  • 10
  • 9
  • 8
  • Tagged with
  • 1057
  • 171
  • 147
  • 133
  • 115
  • 113
  • 102
  • 85
  • 71
  • 70
  • 66
  • 66
  • 59
  • 58
  • 57
  • 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.
61

Quantitative Paleoclimate Reconstructions from the Melville Peninsula, Nunavut, Canada

Adams, Jennifer 14 December 2009 (has links)
A transitional climate and the presence of Thule sites make the Melville Peninsula an area of high importance for paleoenvironmental studies. Lake sediment cores and surface samples from Melville Peninsula were analyzed for diatom assemblages. Fragilarioid diatom species dominate assemblages from the interior of the peninsula since the middle Holocene. The greatest changes in diatom communities occurred during the transition from the Holocene Thermal Maximum to the Neoglacial, and in the post-Little Ice Age period. Species richness reached maximum values in the most recent period, reaching 50.8 species in surface sediments. Diatom-inferred pH reconstruction from two lakes did not indicate substantial change throughout the Holocene despite assemblage changes, showing the complexity of interpreting paleoclimate records dominated by Fragilarioids. Analysis of modern assemblages from the interior and East coast of Melville Peninsula confirm the importance of site size and water chemistry, as determined by bedrock geology, in determining diatom species distributions.
62

Quantitative Paleoclimate Reconstructions from the Melville Peninsula, Nunavut, Canada

Adams, Jennifer 14 December 2009 (has links)
A transitional climate and the presence of Thule sites make the Melville Peninsula an area of high importance for paleoenvironmental studies. Lake sediment cores and surface samples from Melville Peninsula were analyzed for diatom assemblages. Fragilarioid diatom species dominate assemblages from the interior of the peninsula since the middle Holocene. The greatest changes in diatom communities occurred during the transition from the Holocene Thermal Maximum to the Neoglacial, and in the post-Little Ice Age period. Species richness reached maximum values in the most recent period, reaching 50.8 species in surface sediments. Diatom-inferred pH reconstruction from two lakes did not indicate substantial change throughout the Holocene despite assemblage changes, showing the complexity of interpreting paleoclimate records dominated by Fragilarioids. Analysis of modern assemblages from the interior and East coast of Melville Peninsula confirm the importance of site size and water chemistry, as determined by bedrock geology, in determining diatom species distributions.
63

An analysis of one year of surface layer meteorological data from the Arctic pack ice

Baumann, Richard James 17 July 1978 (has links)
The thesis describes the properties of surface wind and air temperature time series recorded at three locations on the pack ice of the Beaufort Sea. Time series consisting of sequential one-half hourly means were constructed for a period of approximately a year. A diurnal fluctuation in air temperature is found for the late summer, early fall and spring seasons only. Wind speed does not show a significant diurnal fluctuation for any season. There is very little seasonal variability in the wind speed while significant variation is present in the air temperature. The integrated wind speed spectrum (i. e. variance) is 80% less than the integrated sum of the wind component spectra indicating that for periods longer than a day, directional fluctuations contribute much more to the variance of the wind record than do speed fluctuations. Although the measurements only approach the microscale region, there seems to be no consistent indication of a microscale peak in the variance preserving representation of the wind speed spectrum. Time series of daily mean horizontal divergence and vertical component of vorticity for both the wind field and ice motion are examined. For a period of 355 days there is significant negative correlation (-0.65) between the wind divergence and wind vorticity series and significant positive correlation (0.65) between the wind vorticity and ice vorticity series. / Graduation date: 1979
64

An assessment of NOGAPS performance in Polar Forecasting from SHEBA data /

Lana, Aaron D. Unknown Date (has links) (PDF)
Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, 2004. / Thesis Advisor(s): Peter Guest. Includes bibliographical references (p. 63-64). Also available online.
65

North Icelandic waters

Stefánnson, Unnsteinn. January 1962 (has links)
Thesis--Copenhagen. / "Reprinted from Rit Fiskideildar, vol. III, 1962." Summaries in Danish and Icelandic. Bibliography: p. [215]-225.
66

Toward quantifying the impact of atmospheric forcing on Arctic sea ice variability using the NPS 1/12 degree pan-Arctic coupled ice-ocean model

Tseng, Hsien-Liang R. January 2010 (has links) (PDF)
Thesis (M.S. in Meteorology and M.S. in Physical Oceanorgraphy)--Naval Postgraduate School, March 2010. / Thesis Advisor(s): Maslowski, Wieslaw ; Stone, Rebecca E. "March 2010." Description based on title screen as viewed on April 26, 2010. Author(s) subject terms: Arctic Sea Ice, Sea Ice Extent, Sea Ice Thickness, Sea Ice Volume, Coupled Ice-Ocean Model, Partial Correlation Coefficient, Surface Air Temperature, Arctic Oscillation, Atmospheric Forcing, Oceanic Forcing. Includes bibliographical references (p.163-168). Also available in print.
67

Fine-scale variability in temperature, salinity, and pH in the upper-ocean and the effects on acoustic transmission loss in the Western Arctic Ocean

Col, Stephen M.D. January 2010 (has links) (PDF)
Thesis (M.S. in Engineering Acoustics)--Naval Postgraduate School, March 2010. / Thesis Advisor(s): Stanton, Tim ; Kapolka, Daphne. "March 2010." Description based on title screen as viewed on April 28, 2010. Author(s) subject terms: Acoustic propagation, transmission loss, Arctic Ocean, temperature salinity pH variability. Includes bibliographical references (p. 83-88). Also available in print.
68

Effects of Natural Disturbance on Arctic Stream Communities

Parker, Stephanie Megan January 2004 (has links) (PDF)
No description available.
69

Phenotypic Divergence of Indigenous and Translocated Arctic Charr (Salvelinus alpinus) Populations in Maine

Michaud, Wendy K. January 2006 (has links) (PDF)
No description available.
70

Multi-model-analysis of Arctic climate trends

Schubert, Jan 26 September 2018 (has links)
No description available.

Page generated in 0.0381 seconds