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 “"Paleoclimate proxy"”.
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Insularity and Interaction: Investigating the role of exchange and inter-island interaction in the Banda Islands, Indonesia
… in the timing of these climate shifts based on paleoclimate proxy records from the eastern and western Pacific. At Banda Islands site PA1, connectedness was relatively high at initial occupation about 3500 BP and peaked around 500 years later. A correlation with an increase in El Niño frequency …
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Hydroclimate variability in Central America during the Holocene inferred from lacustrine sediments in Lake Izabal, eastern Guatemala
… in Central America. Recent hydroclimate proxy records from the region, however, have revealed considerable spatiotemporal complexity in precipitation variability. This complexity is hypothesized to result from the interaction between multiple oceanic-atmospheric processes that converge in …
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ISOTOPIC CONSTRAINTS ON ATMOSPHERIC MOISTURE TRANSPORT PROCESSES IN SOUTH AMERICA
… in the modern climate system, recorded in paleoclimate proxy records, and in general circulation models that we rely on to understand how our climate is changing. Advances in satellite and groundbased instruments in the past decade have improved measurements of isotopes in water vapor. In …
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Exploration of natural climate variability and changes in future events using observations, proxy data and model simulations
… in the field of paleoclimatology to meld proxy data (i.e., indirect measurements of past environmental change through archives such as ice, sediments or corals) with large datasets comprised of model simulations. Additionally, I utilize some of the data science and visualization techniques …
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H and O Isotope Systematics in Volcanic Glass: Hydration Experiments and their Application to Volcanic and Hydrothermal Processes
… δD value that records local meteoric waters as a paleoclimate proxy. Finally, I show that glass rehydration can occur even more rapidly on the timescales in eruptive volcanic plumes with meteoric water sources using H2O–δD compositions in a suite of tephras from the 2009 eruption of Redoubt …
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Assimilation of Seasonal Moisture Variability in North America and Asia for the Last Millennium
… past. Compared with reconstructions using only paleoclimate proxy data, the paleoclimate data assimilation (PDA) considers both proxy data and climate model output, so the PDA reconstructions are consistent with both the climate signals reflected by the proxy data and the physical mechanisms …
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Oxygen isotopes in diatom silica : a new understanding of silica-water oxygen isotope fractionation in diatom frustules and an application of diatom d180 values as a record of paleohydrologic variability in a middle-Pleistocene lacrustine core from the Valles Caldera, New Mexico
… for the use of diatom silica d18O values as a paleoclimate proxy. In the setting of open basin lacustrine environments where bottom temperatures are nearly constant at 4ºC, the maturation effect may facilitate reconstruction of variations in paleowater d18O values without the conflating …
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Biomolecular Controls on Calcium Carbonate Formation by Amorphous and Classical Pathways: Insights from Measurements of Nucleation Rates and Isotope Tracers
Calcified skeletons are produced within complex assemblages of proteins and polysaccharides whose roles in mineralization are not well understood. Researchers have long postulated that living organisms utilize the macromolecules of organic matrices to actively guide the formation of crystal …
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Mechanistic underpinnings of lacustrine brGDGT production, and proteomic vertebrate taxonomic identification of phrynosomatid lizards and arvicoline rodents
… the formation of an established paleotemperature proxy—branched glycerol dialkyl glycerol tetraethers (brGDGTs)— derived from bacteria; 2) The viability of taxonomic identification of North American lizards using proteomic analysis of the collagen (I) (COL1) protein in bone, and this method’s …