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Nalidarturbopauseshear, Titus Yuan

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The USU Na lidar has been upgraded to be able to measure temperature and winds in the lower thermosphere up to ~ 115 km routinely. The new capability, coupled with the existing nightglow instruments at USU, enables the investigation of the extreme large wind and shears in this region and their correlation to the atmospheric gravity waves activities in the upper mesosphere.

2023 August 17 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Florida's Vanishing Heritage: Climate Risk And Adaptation At Florida Heritage Sites, Levi Watson

Electronic Theses and Dissertations, 2020-2023

This thesis examines history and preservation at coastal cultural heritage sites threatened by climate change and explores climate adaptation strategies at two sites on Florida's Atlantic coast. Current climate change models indicate the planet may see as much as 1.1 meters, or four feet, of global average sea level rise by the year 2100, requiring site managers to intervene by using adaptation techniques to improve resilience and guard against the loss of cultural heritage monuments. Understanding the history and importance of these sites to the surrounding communities and their numerous stakeholders is the first step to ensuring these sites remain …

Insar Time Series Analysis To Evaluate Subsidence Risk Of Monumental Chandigarh City (India) And Surroundings, Jungrack Kim, Shih-Yuan Lin, Tejpal Singh, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Groundwater depletion is one of the serious geo-environmental issues causing ground subsidence, which damage buildings, infrastructures and causes loss of life. The quantitative and qualitative evaluation of groundwater variability requires multiple approaches to measure hydraulic head level and geodetic deformation. In this study, we have made efforts to integrate multiple hierarchical space-borne data, including Gravity Recovery and Climate Experiment (GRACE), Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR), geological and hydrological data, to quantify subsidence in Chandigarh city and its surroundings. First, we conducted New-Small BAseline Subsets (NSBAS) and pointwise persistent scatterer (PS) InSAR techniques in parallel, using three-years Sentinel-1 data showing …

Measures And Models Of Visual Acuity In Epipelagic And Mesopelagic Teleosts And Elasmobranchs, Eleanor M. Caves, Tracey Sutton, Eric J. Warrant, Sönke Johnsen

Marine & Environmental Sciences Faculty Articles

Eyes in low-light environments typically must balance sensitivity and spatial resolution. Vertebrate eyes with large "pixels" (e.g., retinal ganglion cells with inputs from many photoreceptors) will be sensitive but provide coarse vision. Small pixels can render finer detail, but each pixel will gather less light, and thus have poor signal relative-to-noise, leading to lower contrast sensitivity. This balance is particularly critical in oceanic species at mesopelagic depths (200–1000 m) because they experience low light and live in a medium that significantly attenuates contrast. Depending on the spatial frequency and inherent contrast of a pattern being viewed, the viewer’s pupil size …

Whistler-Mode Waves In Magnetic Ducts, Anatoly V. Streltsov, Salman A. Nejad

Publications

Observations from the NASA MMS satellites show packages of ELF whistler-mode waves localized inside the small-scale irregularities of the magnetic field. These irregularities are formed by the narrow field-aligned channels where the magnitude of the background magnetic field inside the channel is greater or less than outside. By analogy with the classical density ducts, we introduce the high-B duct (HBD), where the magnitude of the field inside the channel is greater than the outside, and the low-B duct (LBD), where the magnitude of the field inside the channel is less than the outside. We investigate the guiding of the ELF …

Supporting Data For Figures In "Mixing Of The Connecticut River Plume During Ambient Flood Tides: Spatial Heterogeneity And Contributions Of Bottom-Generated And Interfacial Mixing", Michael M. Whitney

Department of Marine Sciences

This archive contains the supporting data for figures in the manuscript "Mixing of the Connecticut River plume during ambient flood tides: Spatial heterogeneity and contributions of bottom-generated and interfacial mixing" by Michael M. Whitney. The objectives of this modeling study are 1) characterizing the spatial heterogeneity of turbulent buoyancy fluxes, 2) partitioning turbulent buoyancy fluxes into bottom-generated and interfacial shear contributions, and 3) quantifying contributions to plume-integrated mixing within the tidal plume. Data are from the Regional Ocean Modeling System (ROMS) results for idealized model configurations. The Zip file (Figure_data.zip) contains MATLAB data files, which are named FigureXX_data.mat. Variable names …

Supporting Data For Figures In "Wind-Enhanced Separation Of Large-Scale River Plumes From Coastal Corners", Michael M. Whitney

Department of Marine Sciences

This archive contains the supporting data for figures in the manuscript "Wind-enhanced separation of large-scale river plumes from coastal corners" by Michael M. Whitney. This study analyzes idealized models to quantify how large-scale river plumes and wind-driven currents interact at perpendicular coastal corners. Data are from the Regional Ocean Modeling System (ROMS) results for idealized model configurations. The Zip file (Figure_data.zip) contains MATLAB data files, which are named FigureXX_data.mat. Variable names and units correspond to graphed data of each figure in manuscript. Full descriptions of research methods and results are included in manuscript.

2023 August 10 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

An Analysis Of Moisture Environments Associated With Mature North Atlantic Tropial Cyclones, Katherine Berislavich

Theses and Dissertations

Tropical cyclone (TC) intensity and structure are affected by their environments, including sea surface temperature, vertical wind shear, and atmospheric moisture. Analyses of TC environments often rely on area-averaged quantities, yet the spatial variability of these fields can affect TC behavior, such as moisture distribution impacting where and how much rain falls. This study identifies spatial patterns of environmental moisture surrounding mature North Atlantic TCs during 2000-2021 in shear of less than 20 knots. Empirical orthogonal function analysis of total column water vapor reveals six dominant patterns. These patterns account for nearly 67% of the variance in the dataset and …

2023 August 3 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Hydrological Dynamics Of Surface-Groundwater Interactions Between Major Springs Of Mammoth Cave And The Green River, Kentucky, Usa, Matthew Cecil

Masters Theses & Specialist Projects

Mammoth Cave is an iconic example of the cave and karst systems that underlie over 50% of the United States and provide around 13% of the world’s population with water resources. These environmental features are vulnerable to drought, pollution, and human impacts. The complex hydrological regime of the Mammoth Cave system has been studied in the past, but there are improvements and updates that can be made to the past research. The dynamics of the surface-groundwater system, particularly reversals of the Green River and how it backfloods into the cave, are some examples. Echo River and River Styx Springs provide …

Improving The Design And Conduct Of Aquatic Toxicity Studies With Oils Based On 20 Years Of Croserf Experience, Wa Stubblefield, M Barron, G Bragin, Me Delorenzo, B De Jourdan, B Echols, Dp French-Mccay, P Jackman, Jr Loughery, Tf Parkerton, D. Abigail Renegar, Jl Rodriguez-Gil

Marine & Environmental Sciences Faculty Articles

Laboratory toxicity testing is a key tool used in oil spill science, spill effects assessment, and mitigation strategy decisions to minimize environmental impacts. A major consideration in oil toxicity testing is how to replicate real-world spill conditions, oil types, weathering states, receptor organisms, and modifying environmental factors under laboratory conditions. Oils and petroleum-derived products are comprised of thousands of compounds with different physicochemical and toxicological properties, and this leads to challenges in conducting and interpreting oil toxicity studies. Experimental methods used to mix oils with aqueous test media have been shown to influence the aqueous-phase hydrocarbon composition and concentrations, hydrocarbon …

2023 August - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Ocean Wave-Coherent Temperature And Humidity Near-Surface Vertical Distributions And Their Effect On Radar Performance Over The Ocean, Mathew James Stanek

Electronic Theses and Dissertations

Large knowledge gaps concerning the effect of ocean surface waves on near-surface vertical distributions of temperature and humidity in the marine atmospheric surface layer exist due to practical limitations and sensor fidelity challenges of direct measurements. Wave effects on these distributions between the wave trough and crest are least studied within the literature. These scalar distributions influence atmospheric refractivity, which can lead to anomalous propagation of electromagnetic energy. Measurements of temperature and humidity are classically made using rocket- or radiosondes and fixed weather stations, and can utilize tethered profiling systems. However, these measurement systems have limitations when obtaining measurements near …

An Analysis Of The Predictability Of The February 2021 Cold Air Outbreak At S2s Timescales, Grace Dines

Legacy Theses & Dissertations (2009 - 2024)

The February 2021 cold air outbreak (CAO) brought long-lasting, freezing temperatures and extreme winter weather to the United States and Canada. The event resulted in major societal and economic impacts, including millions of power outages, hundreds of fatalities, and approximately $25 billion in losses. This thesis first analyzes the synoptic evolution of this CAO in order to explain how Arctic air arrived and stalled over central North America. Given the synoptic context, the analysis next considers the subseasonal-to-seasonal (S2S) predictability of this CAO by examining S2S ensemble model predictions from both high-top and low-top models. The S2S predictability analysis is …

An Assessment Of Coastal Impacts To The Natural And Built Assets Of The New York State Office Of Parks, Recreation And Historic Preservation, Kelsey Ruffino

Legacy Theses & Dissertations (2009 - 2024)

Climate change is expected to cause an increase in heavy precipitation events, flooding, and sea level rise in New York State, which will have significant impacts on coastal areas. Almost half of New York's state parks and historic sites, which are managed by the New York State Office of Parks, Recreation and Historic Preservation (OPRHP), are located in major coastal areas, including the Atlantic Ocean, Hudson River, Lake Erie, and Lake Ontario. As the effects of climate change become more pronounced in these areas, a selection of OPRHP’s infrastructure and natural, cultural, and historic resources will be at risk. To …

An Evaluation Of High-Resolution Model Simulations Of Orographic Precipitation, Snowpack, Atmospheric Rivers, And Their Climate Sensitivities In The Southern Andes, Erin Potter

Legacy Theses & Dissertations (2009 - 2024)

Orographic precipitation and snowpack are important for water resources and hydrometeorological hazards in the Andes Mountain range. As the climate warms, South American atmospheric rivers (ARs) are expected to increase in frequency and intensity, leading to increased orographic precipitation. Improved understanding of orographic precipitation and snowpack, and their association with ARs, in a warming climate is needed to provide a foundation for understanding future hydroclimate change over the Andes. The goal of this research is to evaluate how well variations in high-resolution regional climate simulations over the southern Andes (30-55°S), agree with observations of (1) orographic precipitation and (2) snowpack …

Scenario Planning In A Post-Pandemic World: Karner Blue Butterfly And The Albany Pine Bush, Senia Quevedo

Legacy Theses & Dissertations (2009 - 2024)

This study outlines four future scenarios for the Karner blue butterfly and the Albany PineBush in a post-pandemic world. Management changes and modifications are becoming more necessary due to the changing climate conditions and habitat loss. The COVID-19 pandemic has changed certain conditions that affect the Karner blue butterfly and its habitats, such as noise and air pollution, increased outdoor recreation, and pausing development along the pine bush borders. A scenario planning model was used to better understand how policy and lockdown restrictions being lifted will affect the Karner blue butterfly population after the Albany Pine Bush surveyed a record-high …

The Development Of A Statistical Postprocessing Algorithm By Two-Step Space-Time Eof Analysis, William David Stikeleather

Legacy Theses & Dissertations (2009 - 2024)

Model prediction for extended range forecasts is fraught with shortcomings that generate forecast error and decrease skill. Biases in Numerical Weather Prediction (NWP) models generate patterns of error that grow larger with time. These inherent biases systematically alter the modeled positioning of atmospheric features that emerge as synoptic or subseasonal error. While individual weather events and anomalous patterns will generate model noise, it is computationally possible to separate the signal behind this error from noise. For 200 hPa Geopotential Height (Z200), systematic biases in model forecasts often manifest themselves as errors in atmospheric wave patterns in the high latitudes, including …

Characteristics Of Refractivity And Sea State In The Marine Atmospheric Surface Layer And Their Influence On X-Band Propagation, Douglas Matthew Pastore

Electronic Theses and Dissertations

Predictions of environmental conditions within the marine atmospheric surface layer (MASL) are important to X-band radar system performance. Anomalous propagation occurs in conditions of non-standard atmospheric refractivity, driven by the virtually permanent presence of evaporation ducts (ED) in marine environments. Evaporation ducts are commonly characterized by the evaporation duct height (EDH), evaporation duct strength, and the gradients below the EDH, known as the evaporation duct curvature. Refractivity, and subsequent features, are estimated in the MASL primarily using four methods: in-situ measurements, numerical weather and surface layer modeling, boundary layer theory, and inversion methods.

The existing refractivity estimation techniques often assume …

Applications Of Artificial Intelligence To Improve Coastal Ocean Modeling, Dongliang Shen

Electronic Theses and Dissertations

Numerical Modeling (NM) is widely used to simulate and predict hydrodynamic processes and marine particle movements in coastal oceans, particularly during extreme weather events and emergencies. NM offers the capability to realistically simulate multiple state variables and fill gaps caused by scarce observations. However, inherent uncertainties exist in all NMs, primarily arising from the following three factors: 1) insufficient observations leading to uncertain model initial and boundary conditions, 2) inevitable truncation errors due to coarse model resolution, and 3) imperfect physics parameterization schemes for sub-grid processes, especially those related to waves. The consequences of these uncertainties are that 1) even …

A Framework For Statistical Modeling Of Wind Speed And Wind Direction, Eva Murphy

All Dissertations

Atmospheric near surface wind speed and wind direction play an important role in many applications, ranging from air quality modeling, building design, wind turbine placement to climate change research. It is therefore crucial to accurately estimate the joint probability distribution of wind speed and direction. This dissertation aims to provide a modeling framework for studying the variation of wind speed and wind direction. To this end, three projects are conducted to address some of the key issues for modeling wind vectors.\\

First, a conditional decomposition approach is developed to model the joint distribution of wind speed and direction. Specifically, the …

Nitrogen Cycling In The Lower Chesapeake Bay And Mid- And South Atlantic Bight, Yifan Zhu

OES Theses and Dissertations

Nitrogen (N) is central to marine primary production; its availability often limits the capacity and rates of primary productivity in most of the world’s oceans. Contrastingly, estuaries frequently receive anthropogenic N loading, oftentimes resulting in eutrophication, harmful algal blooms (HABs), and substantially degraded water quality. Nutrient variability in both estuaries and oceanic regimes results from meteorological forcing and physical processes, including wind-induced, tidal, and mesoscale mixing and upwelling. In this dissertation, a comprehensive investigation of N variability and cycling and its links to physical-biogeochemical processes was conducted using time-series monitoring approaches, flux estimations, satellite imaging, biogeochemical measurements, and molecular analyses. …

Workshop Summary Report: Making Waves In Equitable Coastal Resilience: A National Workshop On Social Equity And Coastal Resilience, November 1, 2, And 10, 2022 (Virtual), Juita-Elena (Wie) Yusuf, Cassandra R. Davis, Thomas R. Allen, Joshua Behr, Nicole S. Hutton, Marina Saitgalina, Jennifer L. Whytlaw, Khairul Anuar

School of Public Service Faculty Publications

Workshop Overview

‘Making Waves in Equitable Coastal Resilience: A National Workshop on Social Equity and Coastal Resilience’ was a three-day virtual workshop held in November 2022. The workshop was organized by a project team of faculty and researchers at Old Dominion University and the University of North Carolina at Chapel Hill for the Coastal Resilience Center, a U.S. Department of Homeland Security Center of Excellence. The workshop was intended to bring together researchers and practitioners from government, nonprofit agencies, community organizations, and advocacy groups to discuss issues relevant to coastal resilience and social equity and identify research and practice next …

History Of Ice-Rafting In The Arctic Ocean During Glacial Maxima Through Marine Isotope Stage 6, Shannon M. Cofield

OES Theses and Dissertations

Numerous studies attempted to reconstruct Arctic paleoclimate, specifically ice mass timing and locations, during glacial maxima. While some regions, like the Barents-Svalbard Ice Sheet (BSIS) are well-studied, they may benefit from a high-resolution paleo proxy. Other regions are highly contested, such as the East Siberian Sea or the presence of a central Arctic Ocean ice mass.

This research uses an Fe-grain provenance method to (1) define how the BSIS behaved during Marine Isotope Stage (MIS) 2, 4, and 6, and when it retreated; (2) determine the presence and ages of Shelf Ice Masses (SIMs) in the Beaufort Sea and East …

A Comparative Study Of Vinti-Based Orbit Propagation And Estimation For Cubesats In Very Low Earth Orbits, Ethan Michael Senecal

Mechanical & Aerospace Engineering Theses & Dissertations

In recent years, there has been a growing interest in CubeSats and very low Earth orbit (VLEO) space missions. Mission SeaLion, a collaborative CubeSat mission between Old Dominion University, the U.S. Coast Guard Academy, and U.S. Air Force Institute of Technology, planned to launch a 3U CubeSat into VLEO. The VLEO mission is a particularly challenging environment for navigation and orbit propagation because drag introduces a significant perturbation for orbit models such as SGP4. Additionally, mission requirements left no capacity for attitude determination or control, further reducing knowledge of drag behavior of the satellite in flight. This deficiency is a …

A Preliminary Characterization And Assessment Of Mesophotic Octocoral Microbiomes In The Western Gulf Of Mexico, Edward P. Gniffke

Theses and Dissertations

Mesophotic Coral Ecosystems are highly diverse and productive ecosystems in the western Gulf of Mexico which are composed of, in part, by octocorals (subclass Octocorallia). Despite their importance as foundational organisms octocorals are an understudied group in this region, with little known about their microbial community. Ninety-eight Octocoral samples collected from the western and northwestern Gulf of Mexico were sequenced using 16S rRNA sequencing to characterize their microbial communities. The sequenced microbiomes were generally low in diversity composed of a few core microbial taxa. Octocoral group was the main driver of microbiome composition as opposed to depth, season, region, and …

Tidal Flooding In The Mid-Atlantic Region Of The Us: Water Quality Effects In The Lower Chesapeake Bay, Alfonso Macias Tapia

OES Theses and Dissertations

Many coastal areas around the globe suffer from nutrient pollution and its environmental, social, and economic consequences. Nutrient inputs can come from point (e.g., the end of a pipe) and nonpoint sources, from which the former are better constrained as sampling need only be conducted at a discharge point. Given the temporal and spatially extensive nature of tidal flooding events, they can represent another type of nonpoint source of nutrients to adjacent water bodies heretofore, unexamined and quantified. Most studies examining impacts of tidal flooding have focused on threats to resources on land, such as urban infrastructure and human health …

Investigation Of The Flow Field In The Jack Rabbit Ii Mock Urban Environment Field Tests Using A 1:50 Scale Wind Tunnel Model, Paulo Victor De Freitas Lopes

Graduate Theses and Dissertations

Accidental release of toxic chemicals can put workers and nearby populations at significant risk. Consequence assessment of accidents in urban environments is of particular interest. Urban geometries create wind channels between buildings, along with particularly dangerous areas downwind of buildings, where near-stagnant flow is present. Furthermore, recirculation zones can be formed between buildings, trapping high concentrations of toxic gases at ground level, particularly for denser-than-air gases. In 2015, the Department of Homeland Security conducted the Jack Rabbit II Field Test (JR-II) at Dugway Proving Ground, UT. During JR-II, chlorine was released at the center of a Mock Urban Environment (MUE) …