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Oceanography and Atmospheric Sciences and Meteorology

University of Wisconsin Milwaukee

Theses/Dissertations

2014

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

Phosphorus Recycling By Profunda Quagga Mussels In Lake Michigan, Caroline Mosley Dec 2014

Phosphorus Recycling By Profunda Quagga Mussels In Lake Michigan, Caroline Mosley

Theses and Dissertations

Quagga mussels (Dreissena rostiformis bugensis) act as ecosystem engineers in the southern basin of Lake Michigan, altering physical habitats and biogeochemical processes. Adapted to cold and oligotrophic conditions, profunda quagga mussels thrive on the soft substrate of deeper depths. At a 55 m site (10,000 mussels m-2) offshore from Milwaukee, WI, profunda mussel biomass (g m-2) was 1/3 of biomass (g m-2) measured at a 10 m comparison site (5,000 mussels m-2). Higher densities but less biomass is due to profunda mussels having less tissue for a given length and the population per m2 comprising of mostly small mussels ( …

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A Preliminary Evaluation Of Advanced Dvorak Technique-Derived Intensity Estimate Errors And Biases During The Extratropical Transition Of Tropical Cyclones Using Synthetic Satellite Imagery, Alex Manion Aug 2014

A Preliminary Evaluation Of Advanced Dvorak Technique-Derived Intensity Estimate Errors And Biases During The Extratropical Transition Of Tropical Cyclones Using Synthetic Satellite Imagery, Alex Manion

Theses and Dissertations

Real-time and historical tropical cyclone (TC) intensity estimates during extratropical transition (ET) are derived mainly from satellite-based methods such as the Dvorak Technique (DT) and Advanced Dvorak Technique (ADT). However, the empirical relationships developed between cloud organization patterns and cyclone intensity that underlie the DT and ADT are primarily tropical in nature and thus become less reliable during ET. Preliminary analyses suggest that ADT-derived intensity estimates are weak-biased during ET; however, due to the lack of direct observations of cyclone intensity during ET, the extent to which this is true is unknown. Herein, an attempt to quantify errors during this …

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Multi-Periodic Climate Dynamics: Spectral Analysis Of Instrumental, Short- And Long-Length Proxy Temperature Records, Michael David Madsen Aug 2014

Multi-Periodic Climate Dynamics: Spectral Analysis Of Instrumental, Short- And Long-Length Proxy Temperature Records, Michael David Madsen

Theses and Dissertations

Analyzing 26 short-length (less than 3000 years) instrumental and proxy temperature records and five long-length (greater than 3000 years) proxy temperature records using Discrete Fourier Transform has shown that as the length of significant periods increase in the time domain then so does the power at which the period is observed. A t-test verifies that a positive correlation exist between the length of the significant periods and the power with a confidence level of ∝ >0.05. Significant frequencies with period greater than 30 years are confirmed using Monte Carlo simulations, which were created using a nonlinear approach known as fractional …

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Northern Hemisphere Sea Level Pressure Synchronization And Its Effect On Northern Hemisphere Temperature Variability, Joshua Daniel Verbeten May 2014

Northern Hemisphere Sea Level Pressure Synchronization And Its Effect On Northern Hemisphere Temperature Variability, Joshua Daniel Verbeten

Theses and Dissertations

We consider monthly anomalies of zonally averaged sea level pressure (SLP) in the Northern Hemisphere (NH) from two reanalysis products. A measure of synchronization utilizing correlation coefficient in a five-year sliding window across all latitude pairs is computed over this data. It is found that there have been two NH SLP synchronization episodes since the 1890s, which are significant to approximately three standard deviations. Similar statistically significant synchronization events are seen in simulations of 42 global climate models (GCM) with the dominant synchronization pattern in GCMs proving dynamically consistent with observations. Furthermore, a GCM-based NH temperature anomaly composite shows a …

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Plankton Trophic Structure Within Lake Michigan As Revealed By Stable Carbon And Nitrogen Isotopes, Zachery G. Driscoll May 2014

Plankton Trophic Structure Within Lake Michigan As Revealed By Stable Carbon And Nitrogen Isotopes, Zachery G. Driscoll

Theses and Dissertations

Zooplankton represent a critical component of aquatic food webs in that they transfer energy from primary producers to higher trophic positions. However, their small size makes the application of traditional trophic ecology techniques difficult. Fortunately, novel techniques have been developed that can be used to elucidate feeding information between zooplankton species. I used the analysis of stable carbon and nitrogen isotope ratios to estimate the trophic structure of Lake Michigan's zooplankton community. The major zooplankton species, three size classes of seston, and seston from specific water column depths were collected in 2011 and 2012 for stable isotope analysis. Trophic position …

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Evaluating The Biogenicity Of Fluvial-Lacustrine Stromatolites From The Mesoproterozoic Copper Harbor Conglomerate, Upper Peninsula Of Michigan, Usa, Nicholas David Fedorchuk May 2014

Evaluating The Biogenicity Of Fluvial-Lacustrine Stromatolites From The Mesoproterozoic Copper Harbor Conglomerate, Upper Peninsula Of Michigan, Usa, Nicholas David Fedorchuk

Theses and Dissertations

The Mesoproterozoic (1.09 Ga) Copper Harbor Conglomerate represents alluvial fan, fluvial and lacustrine deposition in the Midcontinent Rift System. The formation outcrops in the Keweenaw Peninsula in the northwestern part of the Upper Peninsula of Michigan where it contains carbonate stromatolites preserved within both siltstone and conglomerate facies. The purpose of this study is to evaluate the biogenicity of these stromatolites, which lack direct microfossil evidence. The stromatolites were placed into their depositional context, their macro-scale features and thin section microfabrics were analyzed, and growth angles were measured of cobble-draping samples to determine if a phototrophic response existed. A methodology …

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Sedimentology And Paleoecology Of Fossil-Bearing, High-Latitude Marine And Glacially Influenced Deposits In The Tepuel Basin, Patagonia, Argentina, Kathryn N. Pauls May 2014

Sedimentology And Paleoecology Of Fossil-Bearing, High-Latitude Marine And Glacially Influenced Deposits In The Tepuel Basin, Patagonia, Argentina, Kathryn N. Pauls

Theses and Dissertations

The glacial and non-glacial intervals of the Late Paleozoic Ice Age (LPIA) are of great interest because they are our best deep time analogue for Pleistocene climate change. The changes and adaptations of the biota, as seen in the rock record, can serve as a proxy for understanding future trends in Earth's climate system. Most of the known LPIA marine faunal data come from low-latitudinal regions, and thus have been used as a global proxy. However, modern organisms in the low-latitudes (far-field basins) respond differently to a changing climate relative to marine organisms in the polar regions (near-field basins). In …

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Re-Examining An Air Mass-Based Approach To Detecting Structural Climate Change, 1948-2011, Joseph James Larsen May 2014

Re-Examining An Air Mass-Based Approach To Detecting Structural Climate Change, 1948-2011, Joseph James Larsen

Theses and Dissertations

Air mass-based approaches to observing changes in climate can have considerable value beyond simple trends of temperature and moisture, providing more thorough understanding of structural climate patterns. Few methodologies have adequately characterized recent air mass modification, however. This research seeks to update and improve upon the methods of a prior study, providing new data from 1948-2011, as well as more rigorous statistical analyses. Air mass types were created, and monthly averages of temperature, dewpoint, and relative frequency were calculated for each of the air masses in all four seasons; then the time series were submitted to regression analysis. The results …

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