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.
Results
Showing 1 to 20 of 32 for “"Last Deglaciation"”.
-
Speleothem-Based Hydroclimate Reconstruction of Northeastern Mexico Across the Last Deglaciation
… Our record captures wet conditions during the Last Glacial Maximum, dry conditions during Heinrich Stadial 1, and wet conditions during the Bolling-Allerod Warming, with implications for defining glacial climate and assessing the Mesoamerican North-South precipitation dipole on millennial to …
-
An inverse approach to understanding benthic oxygen isotope records from the last deglaciation
Observations suggest that during the last deglaciation (roughly 20,000-10,000 years ago) the Earth warmed substantially, global sea level rose approximately 100 meters in response to melting ice sheets and glaciers, and atmospheric concentrations of carbon dioxide increased. This interval may …
-
An inverse approach to understanding benthic oxygen isotope records from the last deglaciation
Observations suggest that during the last deglaciation (roughly 20,000-10,000 years ago) the Earth warmed substantially, global sea level rose approximately 100 meters in response to melting ice sheets and glaciers, and atmospheric concentrations of carbon dioxide increased. This interval may …
-
Inferring ocean circulation during the Last Glacial Maximum and last deglaciation using data and models
Since the Last Glacial Maximum (LGM, ~ 20,000 years ago) air temperatures warmed, sea level rose roughly 130 meters, and atmospheric concentrations of carbon dioxide increased. This thesis combines global models and paleoceanographic observations to constrain the ocean’s role in storing and …
-
Inferring ocean circulation during the last glacial maximum and last deglaciation using data and models
Since the Last Glacial Maximum (LGM, ~ 20,000 years ago) air temperatures warmed, sea level rose roughly 130 meters, and atmospheric concentrations of carbon dioxide increased. This thesis combines global models and paleoceanographic observations to constrain the ocean's role in storing and …
-
Constraining circulation changes through the last deglaciation with deep-sea coral radiocarbon and sedimentary 231Pa/230Th
… the ocean’s role in climate change over the last deglaciation. I present a new method for rapid radiocarbon analyses as a means of age-screening deep-sea corals for further study. Based on age survey results, I selected forty corals from the Drake Passage and thirteen from the Reykjanes Ridge …
-
The Evolution of the El Niño-Southern Oscillation and Tropical Pacific Climate Across the Last Deglaciation
… to millennial-scale climate events over the last 25,000 years. Here, I present new records of tropical Pacific mean state and ENSO variability over the last 25,000 years reconstructed from a high-resolution sediment core recovered from the Eastern Equatorial Pacific (EEP) cold tongue …
-
Constraining circulation changes through the last deglaciation with deep-sea coral radiocarbon and sedimentary ²³¹Pa/²³⁰Th
… the ocean's role in climate change over the last deglaciation. I present a new method for rapid radiocarbon analyses as a means of age-screening deep-sea corals for further study. Based on age survey results, I selected forty corals from the Drake Passage and thirteen from the Reykjanes Ridge …
-
Meltwater injections and their impact on Atlantic meridional overturning circulation and climate during the time period of Heinrich Event 1 and the last deglaciation
… 1a (mwp-1a) and the climate<br/>history of the last deglaciation remains a subject of debate. By combining the<br/>GRIP ?18O ice core record on the new Greenland Ice Core Chronology 2005<br/>(GICC05) timescale with the U/Th-dated Barbados coral record, it is<br/>conclusively derived that mwp-1a …
-
Effects of Glaciation on Volcanism in Iceland
Volcanic eruption rates in Iceland during the last deglaciation increased 5--30 fold from the steady-state rates. This has been understood by the unloading of ice, which increases the decompression rates in the mantle, causing enhanced mantle melting rates. However, existing theoretical work cannot …
-
Weichselian glaciations in the middle Notec River region, northwest Poland
… on correlation of stratigraphical position, clast lithology, fabrics and grain size composition of till units. The lithostratigraphy covers two glacial advances of presumed Weichselian (Vistulian) age. The ice flow pattern during these glacial events was reconstructed using directional …
-
Sodium-Calcium Ratios in the Planktic Foraminifera <i>Trilobatus Sacculifer</i> as a Proxy for Sea Surface Salinity
… sacculifer</em> Na/Ca variability over the last deglaciation from Florida Straits core JPC26. Results show good agreement between our new Na/Ca record with the previously published deglacial δ<sup>18</sup>O<sub>sw</sub> record that is also thought to reflect SSS variability from the same …
-
Reconstructing deglacial ocean ventilation using radiocarbon : data and inverse modeling
Significant changes occurred during the last deglaciation (roughly 10-20 thousand years (ka) before present) throughout the climate system. The ocean is a large reservoir of carbon and heat, however, its role during the deglaciation is still not well understood. In this thesis, I rely on …
-
Reconstructing deglacial ocean ventilation using radiocarbon : data and inverse modeling
Significant changes occurred during the last deglaciation (roughly 10-20 thousand years (ka) before present) throughout the climate system. The ocean is a large reservoir of carbon and heat, however, its role during the deglaciation is still not well understood. In this thesis, I rely on …
-
Holocene development of Lake Lögurinn and Eyjabakkajökull : a multi-proxy approach
… interglacial. After the final phase of the last deglaciation in eastern Iceland, glacially derived sediments more or less ceased to be deposit in Lake Lögurinn between ca. 9000 and 4400 years BP (BP = calendar years before 1950 AD), which suggests that Eyjabakkajökull was much reduced in …
-
Tufa-based reconstructions of Huasco Basin Lake levels
… a preliminary lake level chronology for the last deglaciation. Resolving the timings of past lake level highstands in the South American Altiplano will ultimately provide better understanding of what climate events force the South American Summer Monsoon (SASM) further south. Better insight …
-
Late Quaternary environmental and climatic history of the southern Chilean Lake Region interpreted from coleopteran (beetle) assemblages
… and 14,000 yr B,P., at about the time of the last deglaciation. A fauna with similar characteristics to that of the Valdivian Rain Forest was not in place until about 13,000 yr B.P. No evidence was found to support claims made from palynological studies for a pronounced episode of colder and …
-
Quaternary geology of Rolette County, North Dakota
… feet; and lake sediment deposited during the last deglaciation both on solid ground and on glacial ice), (3) stream sediment {modern stream sediment and sediment deposited during the last deglaciation both on solid ground and on stagnant glacial ice), and {4) mudflow sediment with some glacier …
-
Environmental drivers of coastal evolution
… drivers of coastal change since the last deglaciation. I present case studies from near-field (North Atlantic) and far-field (tropical Pacific) coastal environments. Chapter 2 models the effects of glacial ice retreat on surface hydrology and quantifies resulting effects on fluvial …
Page 1 of 2