Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 9 of 9 for “"Ice ages"”.
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On the origins of the ice ages : insolation forcing, age models, and nonlinear climate change
This thesis revolves about the relationship between orbital forcing and climate variability. To place paleo and modern climate variability in context, the spectrum of temperature variability is estimated from time-scales of months to hundreds of thou- sands of years using a patchwork of proxy and …
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Dust and Pleistocene Ice Ages: Eolian Sediments and Climate Change at Ziegler Reservoir, Snowmass Village, Colorado
… Sangamon interglacial (MIS 5) and the early stages of the Pinedale (early Wisconsin) glacial period (MIS 4). Ziegler Reservoir is positioned on top of a ridge, at an elevation of 2705 m, and has a small watershed area (~14 ha), with little evidence of fluvial sediment transport. Particle size …
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Phylogeography of the Malagasy Ant Species Otontomachus coquereli
… formed by splits during the last two consecutive ice ages, and the geographical positioning of these clusters indicates that these splits coinciding with ice ages were aided by different montane refugia within the species. Together, the data show that climate change and refugia have been the …
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Comparative Phylogenetic Analysis in Populations of the Western Cottonmouth (Agkistrodon Piscivorus Leucostoma) Distributed in Three North American Drainage Basins
… remains unexplored. During the Pleistocene ice-ages populations of cottonmouths were confined to southern refugia in both Texas and Florida (Van Devender and Conant 2000). It is thought that post glacial dispersal patterns using stream corridors have resulted in the present biogeographic …
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Invariant Manifolds of a Toy Climate Model
<p>According to astronomical theory, ice ages are caused by variations in the Earth's orbit. However, ice core data shows strong fluctuations in ice volume at a low frequency not significantly present in orbital variations. To understand how this might occur, the dynamics of a two dimensional …
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Chemostratigraphy of the Early Paleoproterozoic carbonate successions (Kaapvaal and Wyoming cratons)
… between biogeochemical cycling of carbon and ice ages has not been fully appreciated. This research involved the sedimentology and isotope stratigraphy of carbonates and shales in Paleoproterozoic glacially-influenced successions of Wyoming and South Africa. Carbonates of the Vagner Formation …
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Our Ice Age: The Geohistorical Imagination in the Northern Hemisphere
<p>“Our Ice Age: The Geohistorical Imagination in the Northern Hemisphere” contributes to discussions in the environmental humanities about the historical and narrative significance of climate change by examining representations of the ice age, a relatively recent geological moment that began 2.5 …
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De-Isolate: The Water-Food-Shelter Nexus
… cooling. These periods are often referred to as "ice ages" and "interglacials" respectively. Scientists attributed warms oceans and carbon dioxide released from the oceans as the reason for global warming in the past. However, human activities of the recent past, mainly the burning of fossil fuel …
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The life cycle of the parasite Pomphorhynchus tereticollis in reference to 0+ cyprinids and the intermediate host Gammarus spp in the UK.
… and G. fossarum before and during previous ice ages. The misidentification of G. fossarum in the UK and the strong preference of P. tereticollis for one gammarid over another highlights the difficulties in conservation of habitats regarding cryptic species.