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Characterization And Influence Of The Mcmurdo Shear Zone, Antarctica On The Ross Ice Shelf And Its Tributary, Lynn Kaluzienski
Characterization And Influence Of The Mcmurdo Shear Zone, Antarctica On The Ross Ice Shelf And Its Tributary, Lynn Kaluzienski
Electronic Theses and Dissertations
As ice shelves are floating and lack resistive stress at their base, resistance to flow is accommodated along their lateral margins and various pinning points such as ice rises and nunataks. As such, ice shelf shear margins and their strength through time remain a critical control on ice shelf stability. Specifically, lateral shear zone destabilization is an important precursor to ice shelf collapse. In this thesis I utilize in-situ, remote sensing, and numerical modeling techniques in order to characterize the flow field and geometry of the western lateral margin of the Ross Ice Shelf as well as a region upstream …
Coupled Model Sea Surface Temperature Biases And Their Influence On Tropical Cyclone Environmental Conditions In An Atmospheric General Circulation Model, Hunter Tubbs
Electronic Theses and Dissertations
Most climate models participating in the Coupled Model Intercomparison Project, Phase 5 (CMIP5) struggle to accurately simulate all aspects of the climatological global sea surface temperature (SST) distribution, especially in regions of coastal and equatorial upwelling. Of particular interest in this thesis are coupled model SST biases in the tropics and their potential influence on environmental conditions associated with tropical cyclone (TC) genesis and intensity. To evaluate this, two atmospheric general circulation models (AGCMs), the ECHAM5 and CAM5, were employed, first to examine their ability to capture observed TC characteristics when forced with observed SSTs (control runs) and then by …
Modern And Paleo Perspectives On The Role Of The Westerlies In Glaciation, Alexander Audet
Modern And Paleo Perspectives On The Role Of The Westerlies In Glaciation, Alexander Audet
Electronic Theses and Dissertations
Deciphering causes of glaciations and their abrupt terminations over the last >700,000 yrs remains an important problem for understanding the behavior of the climate system and how it might change in the future. In particular, the role of the Southern Hemisphere (SH) Westerlies in global change has arisen as an important research direction. Glaciers are highly sensitive to climate change. Examination of mid-latitude glaciers under the influence of westerly wind systems in both hemispheres can help provide insight into the role of the Westerlies in climate change. In this thesis, I present a twofold strategy to refine knowledge of the …
Quantifying Surface Changes On Mcmurdo Ice Shelf, Antarctica, Ann M. Hill
Quantifying Surface Changes On Mcmurdo Ice Shelf, Antarctica, Ann M. Hill
Electronic Theses and Dissertations
The amount of ice stored in Antarctica has the potential to raise sea level by almost 60 meters. Mass is primarily lost through glaciers draining the ice sheet and flowing into and ice shelves. Ice shelves float on the ocean and act as a resisting force to the flow of the glaciers, thereby modulating the flow of tributary glaciers, and consequently glacier contribution to global sea level rise. McMurdo Ice Shelf (MIS) buttresses four tributary glaciers, three of which will be discussed in this thesis, as well as the northwest corner of the faster flowing Ross Ice Shelf, which has …
Sulfur Isotope Composition Of Sulfides In Mafic Cumulates, Lesser Antilles Arc, Tyler Pollock
Sulfur Isotope Composition Of Sulfides In Mafic Cumulates, Lesser Antilles Arc, Tyler Pollock
Electronic Theses and Dissertations
The sulfur isotope composition of sulfides in igneous rocks from magmatic arcs can be difficult to constrain due to the tendency for sulfur isotopes to fractionate during magma ascent and degassing. Cumulate xenoliths from the lower arc crust are representative of the most primitive magmas of the arc system. The Lesser Antilles arc presents a unique opportunity to investigate the sulfur isotope composition of arc magmas along a magmatic arc with many different magma plumbing systems. Here we present sulfur isotope compositions for primary magmatic sulfide inclusions and secondary interstitial hydrothermal sulfides in mafic cumulates from ten islands along the …
Geology And Lithogeochemistry Of The Pickett Mountain Volcanogenic Massive Sulfide Deposit, Northern Maine, Michael J. Mccormick
Geology And Lithogeochemistry Of The Pickett Mountain Volcanogenic Massive Sulfide Deposit, Northern Maine, Michael J. Mccormick
Electronic Theses and Dissertations
The Pickett Mountain deposit is a volcanogenic massive sulfide (VMS) base-metal deposit located 15 miles north of Patten, ME. The deposit, discovered in 1979, was abandoned in 1989. The deposit remained abandoned until 2017, when Wolfden Mt. Chase LLC purchased the land for further development after Maine mining regulations changed. This project is a collaboration between the University of Maine, the University of Maine – Presque Isle, Wolfden Resources Corp., and the University of New Brunswick to better understand the regional and deposit-scale geology related to the deposit to fill in gaps of the geologic story of northern Maine as …
Comparison Of Land Use And Flowslide Incidence In Palu Valley Following The 2018 Mw 7.5 Palu-Donggala Earthquake, Peta C. Fifield
Comparison Of Land Use And Flowslide Incidence In Palu Valley Following The 2018 Mw 7.5 Palu-Donggala Earthquake, Peta C. Fifield
Electronic Theses and Dissertations
The September 28 Mw 7.5 Palu-Donggala earthquake in Indonesia was the deadliest natural disaster in 2018. Five flowslides on the eastern side of Palu Valley, which were attributed to the substantial majority of deaths and economic losses in the region, occurred due to liquefaction of naturally dry alluvial deposits in gently sloping ground (2 to 6%). The requisite conditions for soil liquefaction are the presence of loose granular sediments and full saturation. Instigation of these catastrophic ground failures were linked to artificial saturation by an unlined agricultural irrigation canal. From a civil engineering perspective, the Palu ground failures on the …
10be Chronology Of Moraines Deposited During The Last Glaciation By The Khumbu Glacier, Nepalese Himalaya, Laura Alexandra Mattas
10be Chronology Of Moraines Deposited During The Last Glaciation By The Khumbu Glacier, Nepalese Himalaya, Laura Alexandra Mattas
Electronic Theses and Dissertations
Understanding the global pattern of glaciation can aid interpretation of what caused late-Pleistocene glacial cycles. Here I investigate the glacial history of the Khumbu Glacier of the Mount Everest region of Nepal. Prominent hypotheses for Himalayan glaciation suggest important roles for orbitally modulated insolation change and the Asian summer monsoon. Here I test these hypotheses by developing a 10Be surface-exposure chronology of moraines constructed by the Khumbu Glacier during the last glacial period. My chronology is underpinned by detailed glacial-geomorphic mapping constructed by use of drone and satellite imagery. The ages presented in this study indicate that the Khumbu glacier …
Examining Summertime Melt And Temperatures In The North Pacific Cordillera, Ingalise Kindstedt
Examining Summertime Melt And Temperatures In The North Pacific Cordillera, Ingalise Kindstedt
Electronic Theses and Dissertations
Temperature changes in glaciated regions are of immediate concern for estimates of future sea level rise. Alaska and the surrounding region contain over 40 mm of potential sea level rise in its many alpine glaciers, which are experiencing some of the highest rates of mass loss globally. However, records of both past and present temperatures in the region’s alpine sectors are sparse and limited in temporal and spatial extent. Here I examine the application of MODIS land surface temperatures and layers of refrozen melt in ice cores as temperature indicators in the St. Elias and Alaska Ranges. First, I find …