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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.
31

A study of bias and random error distributions for atmospheric structure and quasi-Lagrangian budget statistics

Peterson, Robert Edwin. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 191-195).
32

Seasonal variability in the intermediate water of the eastern North Atlantic /

Bray, Nancy Amanda. January 1980 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1980. / Vita. Contract no.: N00014-76-C-0197, NR 083-400. Includes bibliographical references (leaves 156-158).
33

Seasonal variability in the intermediate water of the eastern North Atlantic /

Bray, Nancy Amanda. January 1980 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1980. / Supervised by Nicholas P. Fofonoff. Vita. Includes bibliographical references (leaves 156-158).
34

Relative efficiency of surface energy budgets over different land covers

January 2012 (has links)
abstract: The partitioning of available solar energy into different fluxes at the Earth's surface is important in determining different physical processes, such as turbulent transport, subsurface hydrology, land-atmospheric interactions, etc. Direct measurements of these turbulent fluxes were carried out using eddy-covariance (EC) towers. However, the distribution of EC towers is sparse due to relatively high cost and practical difficulties in logistics and deployment. As a result, data is temporally and spatially limited and is inadequate to be used for researches at large scales, such as regional and global climate modeling. Besides field measurements, an alternative way is to estimate turbulent fluxes based on the intrinsic relations between surface energy budget components, largely through thermodynamic equilibrium. These relations, referred as relative efficiency, have been included in several models to estimate the magnitude of turbulent fluxes in surface energy budgets such as latent heat and sensible heat. In this study, three theoretical models based on the lumped heat transfer model, the linear stability analysis and the maximum entropy principle respectively, were investigated. Model predictions of relative efficiencies were compared with turbulent flux data over different land covers, viz. lake, grassland and suburban surfaces. Similar results were observed over lake and suburban surface but significant deviation is found over vegetation surface. The relative efficiency of outgoing longwave radiation is found to be orders of magnitude deviated from theoretic predictions. Meanwhile, results show that energy partitioning process is influenced by the surface water availability to a great extent. The study provides insight into what property is determining energy partitioning process over different land covers and gives suggestion for future models. / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2012
35

Stream temperature dynamics following riparian wildfire : effects of stream-subsurface interactions and standing dead trees

Leach, Jason A. 11 1900 (has links)
The primary objectives of this study were to address how stream temperature is influenced by (1) spatial variability in energy exchanges, (2) reach-scale stream-subsurface water interactions and (3) the net radiation dynamics associated with standing dead riparian vegetation. Stream temperature, riparian microclimate, and hydrology were characterized for a 1.5 km reach of Fishtrap Creek, located north of Kamloops, British Columbia. Within-reach air temperature and humidity variability was small, while wind speed, net radiation and surface-subsurface interactions exhibited considerable spatially variability. The field data were used to drive a deterministic energy budget model to predict stream temperature. The model was evaluated against measured stream temperature and performed well. The model indicated that the spatially complex hydrology was a significant control on the observed stream temperature patterns. A modelling exercise using three canopy cover scenarios revealed that post-disturbance standing dead trees reduce daytime net radiation reaching the stream surface by one third compared to complete vegetation removal. However, standing dead trees doubled daytime net radiation reaching the stream compared to pre-wildfire conditions. The results of this study have highlighted the need to account for the spatial variability of energy exchange processes, specifically net radiation and surface-subsurface water interactions, when understanding and predicting stream thermal regimes. / Arts, Faculty of / Geography, Department of / Graduate
36

CO2-level Dependent Effects of Ocean Acidification on Squid, Doryteuthis pealeii, Early Life History

Zakroff, Casey J. 12 1900 (has links)
Ocean acidification is predicted to lead to global oceanic decreases in pH of up to 0.3 units within the next 100 years. However, those levels are already being reached currently in coastal regions due to natural CO2 variability. Squid are a vital component of the pelagic ecosystem, holding a unique niche as a highly active predatory invertebrate and major prey stock for upper trophic levels. This study examined the effects of a range of ocean acidification regimes on the early life history of a coastal squid species, the Atlantic longfin squid, Doryteuthis pealeii. Eggs were raised in a flow-through ocean acidification system at CO2 levels ranging from ambient (400ppm) to 2200ppm. Time to hatching, hatching efficiency, and hatchling mantle lengths, yolk sac sizes, and statoliths were all examined to elucidate stress effects. Delays in hatching time of at least a day were seen at exposures above 1300ppm in all trials under controlled conditions. Mantle lengths were significantly reduced at exposures above 1300 ppm. Yolk sac sizes varied between CO2 treatments, but no distinct pattern emerged. Statoliths were increasingly porous and malformed as CO2 exposures increased, and were significantly reduced in surface area at exposures above 1300ppm. Doryteuthis pealeii appears to be able to withstand acidosis stress without major effects up to 1300ppm, but is strongly impacted past that threshold. Since yolk consumption did not vary among treatments, it appears that during its early life stages, D. pealeii reallocates its available energy budget away from somatic growth and system development in order to mitigate the stress of acidosis.
37

The partitioning of energy between geostrophic and ageostrophic modes in a simple model

Errico, Ronald Mark January 1980 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Meteorology, 1980. / Microfiche copy available in Archives and Science. / Bibliography: leaves 156-158. / by Ronald Mark Errico. / Ph.D.
38

Vertically propagating waves in a numerical stratospheric model

Kirkish, Michael Henry January 1979 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Meteorology, 1979. / Bibliography : leaves 40-42. / by Michael Henry Kirkish. / M.S.
39

On determination of the reference state for computation of the available potential energy in a moist atmosphere

Guivens, Norman Roy January 1979 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Meteorology; and, (B.S.)--Massachusetts Institute of Technology, Dept. of Mathematics, 1979. / Microfiche copy available in Archives and Science. / Thesis (B.S.)--M.I.T., Dept. of Mathematics, 1979. / Includes bibliographical references. / by Norman R. Guivens, Jr. / M.S.
40

Ice formation in the Gulf of St. Lawrence.

Lally, Graydon D. (Graydon Douglas) January 1973 (has links)
No description available.

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