Physical Sciences and Mathematics Commons^™

A Multi-Faceted Biogeochemical Approach To Analyzing Hypoxia In Green Bay, Lake Michigan, Shelby Labuhn

Theses and Dissertations

Green Bay, Lake Michigan is a large freshwater estuary that has experienced seasonal hypoxia for decades. Hypoxia, or dissolved oxygen concentrations less than 2 mg L-1, is a problem in coastal ecosystems around the world because it has a negative impact on ecosystem health by decreasing biodiversity and fisheries. In order to create adequate management policies for hypoxia, it is important to understand the sources and sinks of oxygen within Green Bay. This study utilizes a number of traditional and novel field methods to measure the production and respiration of oxygen within lower Green Bay, defined as south of Chambers …

Late Paleo-Indian Period Lithic Economies, Mobility, And Group Organization In Wisconsin, Ethan Adam Epstein

Theses and Dissertations

The following dissertation focuses upon the organization of Pleistocene / Holocene period lithic technology in Wisconsin circa 10,000 – 10,500 years before present. Lithic debitage and flaked stone tools from the Plainview/Agate Basin components of the Heyrman I site (47DR381), the Dalles site (47IA374), and the Kelly North Tract site at Carcajou Point (47JE02) comprise the data set. These Wisconsin sites are located within a post glacial Great Lakes dune environment, an inland drainage/riverine environment, and an inland wetland/lacustrine environment. An assemblage approach is used to examine the structure of each site’s lithic economy. This broad approach to lithic organization …

Convex Grooves In Staggered Herringbone Mixer Improve Mixing Efficiency Of Laminar Flow In Microchannel, Tae Joon Kwak, Young Gyu Nam, Maria Alejandra Najera, Sang Woo Lee, J. Rudi Strickler, Woo-Jin Chang

Freshwater Faculty Articles

The liquid streams in a microchannel are hardly mixed to form laminar flow, and the mixing issue is well described by a low Reynolds number scheme. The staggered herringbone mixer (SHM) using repeated patterns of grooves in the microchannel have been proved to be an efficient passive micro-mixer. However, only a negative pattern of the staggered herringbone mixer has been used so far after it was first suggested, to the best of our knowledge. In this study, the mixing efficiencies from negative and positive staggered herringbone mixer patterns as well as from opposite flow directions were tested to investigate the …

Analysis Of The Run-To-Run Variability Within The Namm Forecasts For The Northeast U.S. Blizzard Of 8-9 February 2013, Kaitlyn Heinlein

Theses and Dissertations

On 8-9 February 2013, a strong extratropical cyclone brought historic winter storm conditions to the Northeast United States with a swath of one to three feet of snow falling across much of New England, with isolated pockets exceeding three feet across south-central Connecticut. Given the high socioeconomic impact that resulted from this blizzard, this study focuses on the run-to-run variability in operational model (North American Mesoscale model; NAM) forecasts leading up to the event. These forecasts, initialized forty-eight hours or less from the start of the event, showed two instances indicating a substantial shift in the expected impact. The first …

Sedimentology Of The Mid-Carboniferous Basal Fill Of The Olta Paleovalley, Eastern Paganzo Basin, Argentina, Levi Darwin Moxness

Theses and Dissertations

As global climate transitioned from the icehouse of the Late Paleozoic Ice Age (LPIA) to greenhouse conditions of the Late Permian, glaciers vanished across Gondwana; however, not all ice centers responded synchronously. The Paganzo basin, northwestern Argentina, was geographically adjacent to significant mid-Carboniferous ice centers that disappeared notably earlier than ice over much of Gondwana. Confining the extent of glacial ice during the LPIA and resolving the timing of its disappearance is of particular interest as this dramatic climatic transition is the closest analogue in Earth history to late Cenozoic climate change, potentially aiding in anticipating the response of modern …

The Selective Survival Of Escherichia Coli In Freshwater Beach Sand, Natalie Ann Rumball

Theses and Dissertations

The quantification of Escherichia coli or E. coli is the most common method used to detect recent fecal pollution in recreational water, as this species is known for its high abundance in fecal matter and assumed host-associated nature. However, it has been determined that some strains are capable of long-term survival and potential propagation in non-host environments, such as the beach sand. These long-term environmental survivors are host-independent and are not associated with the same health risks as those E. coli from recent fecal pollution. However, they have been shown to impact how water quality is perceived as they are …

Characterization Of Dom And Its Interactions With Invasive Quagga Mussels In Lake Michigan, Stephen Devilbiss

Theses and Dissertations

Green Bay is the largest freshwater estuary in the Laurentian Great Lakes and receives disproportional terrestrial inputs. While seasonal hypoxia and the formation of “dead zones” in Green Bay have received increasing attention, there are no systematic studies on the dynamics of dissolved organic matter (DOM) and its linkage to the development of hypoxia. During summer 2014, bulk dissolved organic carbon (DOC) analysis, UV-vis spectroscopy, and fluorescence excitation-emission matrices (EEMs) coupled with PARAFAC analysis were used to quantify the abundance, composition and source of DOM and their spatiotemporal variations in Green Bay, Lake Michigan. Concentrations of DOC ranged from 202 …

On Establishing A Climatology Of Gust Factors And Assessing Their Ability To Forecast Wind Gusts In Milwaukee, Wi, Austin Reed Harris

Theses and Dissertations

Wind gust forecasts are difficult given the small spatial and temporal scales at which they occur. As a result, a variety of statistical and numerical modeling approaches are used to forecast wind gusts, but a best practice has yet to be determined. One statistical approach, called a gust factor, is advantageous in its simplicity, and is often used operationally. Derived empirically from hourly and one-minute wind observations, we establish a climatology of gust factors for the 2000 to 2014 period at Milwaukee, WI. The gust factors are then stratified by wind speed, direction, time of day and year, and stability …

Predictability And Dynamics Of Warm-Core Mesoscale Vortex Formation With The 8 May 2009 "Super Derecho" Event, Caleb Todd Grunzke

Theses and Dissertations

The predictability and dynamics of the warm-core mesovortex associated with the northern-flank of the 8 May 2009 “Super Derecho” event are examined by coupling the Advanced Research Weather Forecasting Model with the Data Assimilation Research Testbed facility. A 50-member convection-allowing EnKF ensemble was produced with 6 hourly-cycled analysis and assimilated observations. Cycled analysis started five days prior to 1200 UTC 7 May 2009, at which time the 36 h ensemble forecasts were launched.

The ensemble forecasts all attempted to produce a mesoscale convective system (MCS) but only fourteen percent produced a warm-core mesovortex-like feature similar to the intensity of the …

The Influence Of Pbl Parameterization On The Practical Predictability Of Convection Initiation During The Mesoscale Predictability Experiment (Mpex), Bryan Burlingame

Theses and Dissertations

This study evaluates the influence of planetary boundary layer (PBL) parameterizations on short-range (0-15 h) forecasts of convection initiation (CI) within convection-allowing ensembles that utilize sub-synoptic-scale observations collected during the Mesoscale Predictability Experiment (MPEX). Running five thirty-member ensembles with the Advanced Research Weather Research and Forecasting Model (WRF-ARW) with each differing only in the chosen PBL parameterization, forecast skill, PBL sensitivity on the environment in which CI occurred, and the variability within are examined. Three MPEX cases, 19-20 May 2013, 31 May-1 June 2013, and 8-9 June 2013 are considered, each characterized by a different large-scale flow pattern to analyze …

The Influence Of Assimilated Targeted Observations Upon Ensemble Forecasts Of Convection Initiation, Alexandra Marie Keclik

Theses and Dissertations

The influence of assimilating targeted meso-α- to synoptic-scale observations collected in the upstream, pre-convective environment upon subsequent short-range ensemble forecasts of convection initiation (CI) across the central United States for the fifteen aircraft missions conducted by the Mesoscale Predictability Experiment (MPEX) in May and June 2013 is evaluated in this study. Utilizing the ensemble Kalman filter implementation within the Data Assimilation Research Testbed software package as coupled to version 3.4.1 of the Advanced Research version of the Weather Research and Forecasting model, two nearly-identical thirty- member ensembles of short-range forecasts are conducted for each mission. Initial conditions for one ensemble …

Inter-Decadal Shifts In Intense Extratropical Cyclones In The Northern Hemisphere, Timm Uhlmann

Theses and Dissertations

Cyclones, both tropical and extratropical, have a large socioeconomic impact during any given year. Understanding the formation and evolution of these cyclones in the current climate therefore becomes imperative to minimize loss to property and life. Previous work by Kossin et al (2014) showed a significant poleward migration for the most intense tropical cyclones from 1982 to 2009. This sparks the interest in whether extratropical cyclones exhibit a similar trend within a changing climate. Data used stems from the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim Analysis for an analogous time period from 1980-2015. Tracking and identification of cyclones …

Improving The Subgrid-Scale Representation Of Hydrometeors And Microphysical Feedback Effects Using A Multivariate Pdf, Brian Martin Griffin

Theses and Dissertations

The subgrid-scale representation of hydrometeor fields is important for calculating microphysical process rates. In order to represent subgrid-scale variability, the Cloud Layers Unified By Binormals (CLUBB) parameterization uses a multivariate Probability Density Function (PDF). In addition to vertical velocity, temperature, and moisture fields, the PDF includes hydrometeor fields. Previously, each hydrometeor field was assumed to follow a multivariate single lognormal distribution. Now, in order to better represent the distribution of hydrometeors, two new multivariate PDFs are formulated and introduced in part one of this two-part project.

The new PDFs represent hydrometeors using either a delta-lognormal or a delta-double-lognormal shape. The …