Physical Sciences and Mathematics Commons^™

Fish Assemblage Structure In Great Lakes Coastal Wetlands Over Ten Years, Matthew S. Silverhart

Masters Theses

Coastal wetlands in the Laurentian Great Lakes are important habitats for many fish species. The geographic scale of the watershed and the diversity of land uses in the region result in substantial environmental variation among coastal wetlands. During 2011-2020, annual surveys were conducted as part of the Great Lakes Coastal Wetland Monitoring Program (GLCWMP) to better understand the status and trends of coastal wetlands. Fish sampling consisted of fyke netting in monodominant vegetation zones. During this time, 1225 unique monodominant plant zones in coastal wetlands were sampled, resulting in 584,125 fishes captured that consisted of 113 different species. Yellow Perch …

Hysplit In Simulating The Atmospheric Dispersion Of Hazardous Aerosols: A Case Study In St. Louis, Missouri, Ahmet Tolga Odabasi

Masters Theses

"Atmospheric dispersion and transmission play an important role in the behavior and effects of air pollution. Human health can be adversely affected by air pollution in a variety of ways, both immediately and over time. The Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) modeling program, a computer model and software package, tracks the transport trajectories and distributions of air pollution and various pollutants, including radioactive pollutants, in the atmosphere. It also facilitates research on pollution sources. This study simulated the transport of hazardous aerosols in St. Louis region for the years 2020, 2021, and 2022 using the HYSPLIT modeling …

Unearthing Complexity: Tangible Histories Of Water And Earth, Alexis Violet

Masters Theses

Unearthing Complexity investigates conceptions of time and surface through geological stories of the water and earth. Building on theories of deep time, hydrofeminism, critical zones, and grounding, I hope to foster a deeper awareness of time scales other than our own and a more tangible understanding of the embodied experience of matter in the universe. Working toward a new literacy of the water and earth in which they are recognized as living, changing bodies to which we are inherently tied at a molecular level, the site of this multiscalar inquiry occurs in the coastal zones of the Narragansett Bay where …

Modeling Spatial Distributions Of Tidal Marsh Blue Carbon Using Morphometric Parameters From Lidar, Bonnie Turek

Masters Theses

Tidal marshes serve as important “blue carbon” ecosystems that accrete large amounts of carbon with limited area. While much attention has been paid to the spatial variability of sedimentation within salt marshes, less work has been done to characterize spatial variability in marsh carbon density. Driven by tidal inundation, surface topography, and sediment supply, soil properties in marshes vary spatially with several parameters, including marsh platform elevation and proximity to the marsh edge and tidal creek network. We used lidar to extract these morphometric parameters from tidal marshes to map soil organic carbon (SOC) at the meter scale. Fixed volume …

Running Out Of Oxygen: Revealing The Interannual And Intra-Annual Dynamics Of Bottom Water Hypoxia In A Great Lakes Estuary Using Time-Series Observations, Experiments, And Analyses, Nate M. Dugener

Masters Theses

Bottom water hypoxia, a condition of low dissolved oxygen in the bottom waters, negatively effects lakes and freshwater and marine coastal estuaries globally. As climate change shifts climatological and ecological patterns, hypoxia continues to shift in duration and severity. In Muskegon Lake, Michigan, hypoxia occurs annually, restricting fish habitat, increasing cyanobacteria blooms, and disrupting ecological and socioeconomic prosperity. In the current study, we examined the duration and severity of hypoxia over a 11 years (2011-2021) utilizing data from the Muskegon Lake Observatory buoy (MLO, https://www.gvsu.edu/wri/buoy/). During 2021, we analyzed the dissolved oxygen (DO) concentrations observed by the MLO, conducted biweekly …

Identifying New Invasives In The Face Of Climate Change: A Focus On Sleeper Populations, Ayodelé C. O'Uhuru

Masters Theses

Sleeper populations are established populations of a non-native species whose population growth is limited by one or more abiotic or biotic conditions, such as climate change. While the northeastern US is predicted to be a hotspot for future invasions, identifying potential sleeper populations before they become invasive can inform proactive, climate-smart invasive species management. I focused on 169 introduced species that are established in one or more northeastern states. I used the Environmental Impact Classification for Alien Taxa (EICAT) framework to systematically identify and review the peer-reviewed literature for these candidate species to quantify their negative ecological and socioeconomic impacts. …

Coastal Groundwater Catchments Of The Gulf Of Alaska, Aeon Russo

Masters Theses

High latitude mountain environments are experiencing disproportionately adverse effects in a currently changing climate. The Gulf of Alaska (GoA) region is an exemplar of this. Dramatic shifts are occurring in the region’s freshwater reservoirs as glaciers retreat more with each passing year. Research in the region places much focus on observing and predicting climate driven shifts in glacier mass balance, surface discharge, and associated nutrient fluxes to the ocean. On the other hand, coastal groundwater discharge (CGD) is given very little attention. Global and near-global estimates of CGD indicate variable results spanning an order of magnitude. Focusing on regionally specific …

Hydrologic Structure And Function Of Vernal Pools In South Deerfield, Massachusetts, Charlotte Axthelm

Masters Theses

Vernal pools are small, ephemeral wetlands lacking an inlet or outlet. These wetlands, also known as seasonal pools, are found in a wide range of biomes, and their characteristics vary based on location. While the vegetation of western U.S. pools, and amphibians of eastern U.S. pools have been extensively studied, many aspects of vernal pools have not been fully characterized. In particular, although the general seasonal wetting and drying cycle is understood qualitatively, few studies have attempted to quantify the hydrological regime of vernal pools in New England. As water level variation drives many, if not all, of the characteristics …

Mid-Pliocene To Early Pleistocene Sea Surface And Land Temperature History Of Nw Australia Based On Organic Geochemical Proxies From Site U1463, Rebecca Smith

Masters Theses

Ocean gateways facilitate water circulation between ocean basins, and therefore directly impact thermohaline circulation and global climate. In order to better predict the effects of future climate change, it is critical to constrain past changes in ocean gateway behavior, and corresponding changes in thermohaline circulation, particularly during analogue periods for modern climate change. The Indonesian Throughflow (ITF) is a primary ocean gateway and vital component of the global conveyor that transports water from the Pacific Ocean into the Indian Ocean, however due to a lack of long and continuous sedimentary records from locations under its influence, changes in ITF behavior …

Spatio-Temporal Variability Of Precipitation And Drought In The State Of Arizona, Usa, Samuel Nimako Nyarkoh

Masters Theses

As a result of climate change, several dry regions continue to get drier as precipitation amounts decline. This decline impact water resources and hinder economic development. Understanding the variability of precipitation and drought through climatic, agricultural and hydrological studies is therefore critical to decision makers and stakeholders in developing proactive measures that promotes economic development.

This study therefore uses dataset from 55 Meteorological stations containing 110-year (1900-2010) monthly precipitation data and a series of spatial and temporal tests to investigate the spatial and temporal patterns of precipitation and drought as well as the effects of local factors such as topography …

Determinants Of Household Water Use In The City Of Kalamazoo, Michigan: The Role Of Climate And Socioeconomic Factors, Danielle Molenaar

Masters Theses

Located in the Great Lakes Watershed, the City of Kalamazoo can be considered “water rich”. Therefore, the area has been absent from water use studies. Water use studies are beneficial in all locations; as they can aid city planners, water resource managers, and utility companies. This study examines how household monthly water use in the City of Kalamazoo is impacted by both climate and socioeconomic variables over the period 2006-2016. Household level data were aggregated into census tracts to obtain monthly tract averages for the eleven-year period. Ordinary least squares regression (OLS) was used to determine which variables impact the …

Interannual Variations Of Snowfall In The Lower Peninsula Of Michigan And Impacts Of Local And Remote Meteorological Conditions, Nirjala Koirala

Masters Theses

Inter-annual variation of snowfall and its relation to climate indices will help clarify and improve the prediction of total snowfall in the Lower Peninsula of Michigan (LPM). This study examines the trend and variability of annual snowfall (November- March) using 8 homogeneous weather stations in the LPM. The statistical relationship between snowfall and air temperature, Sea Surface Temperature (SST), North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO) and Maximum Ice Coverage(MIC) of Lake Michigan is calculated. The long-term trend in the snowfall data set from 1950 to 2015 is removed before any statistical correlation analysis is conducted. My analysis suggests …

Impact Of Temperature Increase On Freshwater Fish Species: Energetics And Muscle Mechanics Of Two Centrarchids, Israt Jahan

Masters Theses

Fishes have evolved physiologically to live within a specific range of environmental variation and existence outside of that range can be stressful or fatal. These ranges can coincide for fishes that evolved in similar habitats. This study investigates physiological processes limiting thermal tolerance, specifically how changes in water temperature affect the swimming energetics and muscle mechanics in largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus). I focused on the impact of temperature change at the muscle level in these two species and the capacity to adapt to rapid changes in the environment. Fish were housed at …

Juvenile River Herring In Freshwater Lakes: Sampling Approaches For Evaluating Growth And Survival, Matthew T. Devine

Masters Theses

River herring, collectively alewives (Alosa pseudoharengus) and blueback herring (A. aestivalis), have experienced substantial population declines over the past five decades due in large part to overfishing, combined with other sources of mortality, and disrupted access to critical freshwater spawning habitats. Anadromous river herring populations are currently assessed by counting adults in rivers during upstream spawning migrations, but no field-based assessment methods exist for estimating juvenile densities in freshwater nursery habitats. Counts of 4-year-old migrating adults are variable and prevent understanding about how mortality acts on different life stages prior to returning to spawn (e.g., juveniles …

Convective Mode Climatology Of Tennessee Tornado Events And Effect On National Weather Service Warning Processes, Kelly Nicole Gassert

Masters Theses

Tennessee resides in the Southeastern United States, a region prone to violent tornadoes on a year-round basis. With one of the highest tornado fatality rates in the country, and a climatology that varies across the state, analysis of storms resulting in Tennessee tornadoes is necessary for improving forecasting techniques and decreasing loss of life. This study analyzed convective modes responsible for Tennessee tornadoes from 2003 to 2014 to determine an association with fatalities, seasonality, day and night, tornado magnitude, regionality, and multiple-tornado days. Chi-squared tests were conducted to determine if these patterns were significant. National Weather Service forecasters from the …

Determining Sources Of Nitrate In The Semi-Arid Rio Grande Using Nitrogen And Oxygen Isotopes, Diego Alberto Sanchez Hernandez

Masters Theses

The Rio Grande, a semi-arid river in the American Southwest, is a major source of surface water for agriculture and drinking supplies in New Mexico and Texas. In addition to increasing salinity, considerable increases of NO₃^- [nitrate] have been observed in the semi-arid portion of the Rio Grande. It is possible that elevated water salinity inhibits denitrification on irrigated fields and, thus, fails to mediate excess nutrient load from anthropogenic activities. Therefore, two major goals of this project were to 1) characterize and quantify major NO₃^- sources, and 2) assess whether elevated water salinity affects microbial …

Ecological Consequences Of Lost Anadromous Forage Fish In Freshwater Ecosystems, Steven R. Mattocks

Masters Theses

Beginning in the early 1600s, dam construction in New England obstructed anadromous fish access to spawning grounds during migration. As a result, anadromous forage fish populations have declined, which has impacted freshwater, marine, and terrestrial ecosystems. To determine the impacts of dams on anadromous forage fish and freshwater ecosystems, I used historical and current data to estimate population changes in alewives (Alosa pseudoharengus) from 1600-1900. A significant reduction in spawning habitat occurred in New England as a result of 1,642 dams constructed between 1600 and 1900, resulting in 14.8% and 16.6% lake and stream habitat remaining by 1900, …

Trends In Location Of Lifetime Maximum Intensity Of Tropical Cyclones In The North Atlantic And West Pacific Oceans, Sarah Ann Bleakney

Masters Theses

Tropical cyclones threaten coastal populations around the world each year. Thus, the climatology of tropical cyclones is an immediate research need, specifically to better understand their long-term patterns and elucidate their future in a changing climate. One important pattern that has recently been detected is the poleward shift of the lifetime maximum intensity (LMI) of tropical cyclones in the Northern Hemisphere. My study further assesses the recent spatial changes in the LMI of tropical cyclones in the Northern Atlantic and Western Pacific basins since 1964. I explored relationships between the intensity and location of LMI with respect to landfall location …

Knoxville Microclimates: Spatial And Temporal Variability In Ambient Air Temperature Across Four Urban Neighborhoods, David Andrew Howe

Masters Theses

The urban heat island (UHI), has been studied extensively over the past 30 to 40 years, yet questions remain regarding the spatiotemporal variability of the UHI, and what factors influence this variability. More recent studies have emphasized the microclimates within an urban setting, but most do not have the high resolution climate or land cover data necessary to truly understand the interactions taking place at a neighborhood-level scale. This study used a network of 10 identical weather stations and high resolution land use data in Knoxville, Tennessee to analyze the microclimates of a medium-sized city with a temperate climate over …

Rare Occurrences Of Free-Living Bacteria Belonging To Sedimenticola From Subtidal Seagrass Beds Associated With The Lucinid Clam, Stewartia Floridana, Aaron M. Goemann

Masters Theses

Lucinid clams and their sulfur-oxidizing endosymbionts comprise two compartments of a three-stage, biogeochemical relationship among the clams, seagrasses, and microbial communities in marine sediments. A population of the lucinid clam, Stewartia floridana, was sampled from a subtidal seagrass bed at Bokeelia Island Seaport in Florida to test the hypotheses: (1) S. floridana, like other lucinids, are more abundant in seagrass beds than bare sediments; (2) S. floridana gill microbiomes are dominated by one bacterial operational taxonomic unit (OTU) at a sequence similarity threshold level of 97% (a common cutoff for species level taxonomy) from 16S rRNA genes; …

Using Digital Elevation Models Derived From Airborne Lidar And Other Remote Sensing Data To Model Channel Networks And Estimate Fluvial Geomorphological Metrics, Noah Slovin

Masters Theses

Recent advances in remote-sensing technologies and analysis methods, specifically airborne-LiDAR elevation data and corresponding geographical information system (GIS) tools, present new opportunities for automated and rapid fluvial geomorphic (FGM) assessments that can cover entire watersheds. In this thesis, semi-automated GIS tools are used to extract channel centerlines and bankfull width values from digital elevation models (DEM) for five New England watersheds. For each study site, four centerlines are mapped. LiDAR and NED lines are delineated using ArcGIS spatial analyst tools with high-resolution (1-m to 2-m) LiDAR DEMs or USGS National Elevation Dataset (NED) DEMs, respectively. Resampled LiDAR decreases LiDAR DEM …

A High-Resolution Paleoenvironmental And Paleoclimatic History Of Extreme Events On The Laminated Sediment Record From Basin Pond, Fayette, Maine, U.S.A., Daniel R. Miller

Masters Theses

Future impacts from climate change can be better understood by placing modern climate trends into perspective through extension of the short instrumental records of climate variability. This is especially true for extreme climatic events, such as extreme precipitation and wildfires, as the period of instrumental records provides only a few examples and these have likely have been influenced by anthropogenic warming. Multi-parameter records showing the past range of climate variability can be obtained from lakes. Lakes are particularly good recorders of climate variability because sediment from the surrounding environment accumulates in lakes, making them sensitive recorders of climate variability and …

Dissolution, Ocean Acidification And Biotic Extinctions Prior To The Cretaceous/Paleogene (K/Pg) Boundary In The Tropical Pacific, Serena Dameron

Masters Theses

The several million years preceding the Cretaceous/Paleogene (K/Pg) boundary has been the focus of many studies. Changes in ocean circulation and sea level, extinctions, and major volcanic events have all been documented for this interval. Important research questions these changes raise include the climate dynamics during the warm, but not hot, time after the decay of the Late Cretaceous greenhouse interval and the stability of ecosystems prior to the mass extinctions at the end-Cretaceous.

I document several biotic perturbations as well as changes in ocean circulation during the Maastrichtian stage of the latest Cretaceous that question whether the biosphere was …

Detecting Tropical Cyclone Signals In Tree Rings Of Longleaf Pine (Pinus Palustris Mill.), Valdosta, Georgia, U.S.A., Savannah Anne Collins

Masters Theses

The study of past hurricanes to help interpret the patterns of current and future tropical storms is vital to our economy, society, and infrastructure. Understanding how hurricanes are influenced by a warm climate is critical, and hurricane reconstructions from former periods of the Holocene (the last ~11,500 yr) will be beneficial. Paleotempestology is the study of past tropical cyclones and uses historical, biological, and geological proxies to reconstruct tropical cyclone activity to create a record of historical hurricane patterns. A tropical cyclone (TC) is a chaotic weather event that is influenced by several elements, including warm ocean waters from which …

Sedimentological, Geochemical And Isotopic Evidence For The Establishment Of Modern Circulation Through The Bering Strait And Depositional Environment History Of The Bering And Chukchi Seas During The Last Deglaciation, Ben M. Pelto

Masters Theses

Sea level regression during the Last Glacial Maximum exposed the Bering Land Bridge, and cut off the connection between the North Pacific and Arctic Ocean, ending the exchange of North Pacific Water through the Bering Strait. Exchange of North Pacific Water comprises a major portion of fresh water input to the Arctic Ocean, and is of vital importance to North Atlantic Deep Water formation, a vital component of Atlantic Meridional Overturning Circulation. Bering Strait throughflow thus plays an integral role in global climate stability. A suite of four cores was selected, three in the Bering Sea and one in the …

Measuring Carbon Dioxide (Co2) Flux Of Agricultural Practices In Sub-Saharan Africa, Debra Blumberg O'Dell

Masters Theses

Agriculture has an important role in addressing two of the world’s most pressing problems: meeting global food demand and mitigating climate change. If agriculture is not practiced sustainably it will fail to meet future food demand and likely intensify the pace of global climate change. There are some agricultural practices, such as Conservation Agriculture, that can produce food sustainably and have the potential to mitigate climate change. However it is not clear which agricultural practices contribute to climate mitigation and by how much. By measuring the carbon dioxide (CO2) emissions of specific agricultural practices, the ability of practices to sequester …

A Climatological Study Of Drought In Southern Michigan, Rudy Bartels

Masters Theses

Drought has become a reoccurring phenomenon throughout many regions around the world. Significant drought conditions have beenobserved overthe pastfive decades in relation to economic, social, and agricultural impacts. In this study, Southern Michigan is investigated over the past 52 years from 1960-2012. The Standardized Precipitation Index (SPI) will be calculated over a 6-month timescale from monthly precipitations. Three variables including 500-mb heights, surface pressure maps, and sea surface temperatures, will be correlated with the SPI using sliding correlations and Pearson's R correlation to determine any relations between these variables and precipitation variations. We will further investigate the five driest, wettest, …

Ethical Ambivalence In Local Television Weathercasting: A Rossian Analysis, Vernon Keith Thompson

Masters Theses

Today’s television weathercasters are being called upon increasingly to go beyond benign weather prognostications to become the “newsroom experts” for science topics. The expectation to act as both scientists and journalists can cause ethical ambivalence (EA), a sociological condition in which, faced with conflicting norms, the subject feels that he/she is being pulled psychologically in two different directions (Jansen & Von Glinow, 1985). This thesis presents a Rossian analysis of climate change in weathercasting, a topic that captures the most important ethical tensions arising from conflicting duties within the weathercaster role, specifically: a) how might the duties of the television …

A 7600-Year Record Of Environmental History From The Sediments Of Laguna Tortuguero, Puerto Rico, Alice Renee Schoen

Masters Theses

In 1987, Burney and collaborators (Journal of Archaeological Science (1994) 21, 273–281) recovered a ca. 8 m sediment core from the western basin of Laguna Tortuguero, Puerto Rico that spanned the last ca. 7000 calibrated years. They produced a detailed microscopic charcoal record, and from an initial peak in charcoal at ca. 5300 cal yr B.P. suggested that humans had colonized the island some 2000 years earlier than documented by the archaeological evidence then available. In 2008, two sediment cores were recovered from the eastern basin of Laguna Tortuguero. AMS dates on macrofossils indicate the profile extends to 7600 calibrated …

An Investigation Of Atmospheric Turbulence Probes With Ground Test Comparisons Of Probe Head Designs And Evaluation Of Suitability To Instrumented Aircraft, Charles F Lams

Masters Theses

A comparison of methods to determine the flow angle components of atmospheric velocity vectors is presented. The atmospheric turbulence probes used to measure behavior of the atmosphere use different methods to obtain this information and there is some confusion as to which method is best. Although the methods are all based upon potential flow theory, the details about how the atmospheric and flight parameters are measured makes a difference to the design of an atmospheric turbulence probe and carrier research aircraft. This paper presents the mathematical theory behind five methods of obtaining atmospheric flow angle measurements from a moving aircraft. …