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2024 March 7 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

2024 March - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Global Empirical Model Of Sporadic-E Occurrence Rates, Eli V. Parsch

Theses and Dissertations

Encompassing the Earth, the ionosphere presents unique challenges to modern communication, navigation, and surveillance technologies. Intense ionization enhancements known as sporadic-E (Es), can degrade and disrupt signals in unpredictable ways. Much work has been done to understand this phenomenon and more recent efforts have attempted to model its behavior and impacts. However, there have been limited efforts at modeling global Es occurrence rates (OR) at high time resolutions. This study develops a global empirical model of blanketing sporadic-E (fbEs) occurrence rates using a Karhunen-Lo´eve Expansion (KLE) of global fbEs OR climatologies built with Global Positioning System radio occultations (GPS-RO) and …

Investigation Of High-Latitude Gnss Radio Occulation Sporadic-E And Auroral-E Measurements, Kyle D. Roberts

Theses and Dissertations

Abnormal sporadic-E (E_s) occurrences were found in the high latitude regions during a recent climatology study by (Hodos, 2022), that calculated sporadic-E occurrence rates derived from a data set of GPS radio occultation (GPS-RO) and ionosondes. In this study, sporadic-E GNSS-RO techniques are shown to falsely attribute sporadic-E events to auroral-E (E_a) events. A comparative study is conducted on GPS-RO measurement techniques to find false occurrence rates for various RO techniques using a single ionosonde site in Gakona, Alaska. Phase-based RO techniques were found to be more likely to falsely attribute sporadic-E as auroral-E, while amplitude …

Modeling Lightning Flashes In Dissimilar Non-Homogeneous Clouds, Scott R. Wolff

Theses and Dissertations

A new methodology for near-infrared lightning radiative transfer through clouds is presented. High-resolution weather modeling is used to generate realistic three-dimensional non-homogeneous clouds, which are then used as environments for a Monte Carlo simulation of photon multiple scattering from approximations of lightning flashes. Resultant emissions from the cloud tops are in line with previous studies and satellite observations.

Center Fixing Tropical Depressions And Tropical Storms Using Machine Learning-Nighttime Visible Imagery, Nathan K. Stanford

Theses and Dissertations

The first step in most TC-retrieval algorithms is determining the storm’s central position. In mature TCs, the center is highlighted by a distinct eye and curved band pattern; however, in intensifying and decaying storms, the center is often obscured by thick clouds or overlying cirrus. This study assesses the benefits of incorporating machine learning-derived nighttime visual imagery to improve analysis of center fix in intensifying and decaying TD- and TS-strength TCs during periods of darkness and when polar orbiting satellites are unavailable. The study is divided into two parts: the first, an objective analysis using the ARCHER-2 algorithm, and the …

Assessing The Relationship Between The Quasi-Biennial Oscillation And D-Region Electron Density, Natalie R. Wirth

Theses and Dissertations

High frequency (HF) communication is a vital aspect of military communication and is highly reliant upon ionospheric conditions. The variation in electron density within the lowest echelon of the ionosphere, the D-region, can significantly impact HF signals, making communication inconsistent and unreliable for these wavelengths. Despite the D-region’s important, research in this area mainly focuses on understanding the impact of space weather anomalies on the upper ionosphere, particularly its higher layers, with relatively little exploration of the D-region. This region, situated closest to the troposphere and stratosphere, has been definitively linked to solar weather events like solar flares and geomagnetic …

Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq

Faculty Publications

Rainfed agriculture is the mainstay of economies across Southern Africa (SA), where most precipitation is received during the austral summer monsoon. This study aims to further our understanding of monsoon precipitation predictability over SA. We use three natural climate forcings, El Niño–Southern Oscillation, Indian Ocean Dipole (IOD), and the Indian Ocean Precipitation Dipole (IOPD)—the dominant precipitation variability mode—to construct an empirical model that exhibits significant skill over SA during monsoon in explaining precipitation variability and in forecasting it with a five-month lead. While most explained precipitation variance (50%–75%) comes from contemporaneous IOD and IOPD, preconditioning all three forcings is key …

Low-Temperature Laboratory Instrumentation For Investigating Ice Crystal Aggregate Formation In The Atmosphere, Victor Ojo, Imteaz Osmani, Hallie Boyer Chelmo

Graduate Research Achievement Day Posters

This study addresses the challenge of achieving controlled low temperatures to investigate and provide information on the precise conditions that promote homogenous (≤-38oC) and heterogenous (≥ -38oC) atmospheric ice crystal formation and aggregation, which disrupt aerospace industries and military activity. I present a preliminary design of a novel temperature control setup for generating levitated ice crystal aggregates within a Dual Balance Electrodynamic Trap (DBET). This preliminary design is called the replica low temperature electrodynamic balance (R-LTDBET). The design integrates chilled-coolant-conveying copper tubes encircling the hollow-square-shaped DBET’s external wall to precisely control its inner chamber temperature while incorporating real-time temperature sensing, …

2024 February 29 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Vulnerability Assessment Of Mangroves In Western Shore Of Red Sea, Nada Negm

Theses and Dissertations

Mangroves are vital to environmental sustainability and acts as a global warming control, although they endure severe vulnerability due to some human activities. Climate change and other extrinsic stresses are factors that play a vital role when assessing the vulnerability of mangroves in the Red Sea. The aim of this study is to assess the vulnerability of mangroves using field and RS data to apply a vulnerability index of mangroves at Hamatta and Safaga in Egypt. Mangrove Vulnerability Index covers includes hazard mangrove index, biological mangrove index and physical mangrove index.

Mangrove height has been measured using meter tape and …

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch, Mareli Sanchez-Julia, Sarah A. Batterman, Caroline Dallstream, Claire Fortunel, Laura Toro, Lucia Fuchslueger, Michelle Y. Wong, Daniela Yaffar, Joshua B. Fisher, Marie Arnaud, Lee H. Dietterich, Shalom D. Addo-Danso, Oscar J. Valverde-Barrantes, Monique Weemstra, Jing Cheng Ng, Richard J. Norby

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …

2024 February 22 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Evaluating Future Water Availability In Texas Through The Lens Of A Data-Driven Approach Leveraged With Cmip6 General Circulation Models, Wenzhao Li, Dongfeng Li, Hesham El-Askary, Joshua B. Fisher, Zheng N. Fang

Mathematics, Physics, and Computer Science Faculty Articles and Research

Climate change is escalating the frequency and intensity of extreme precipitation events, significantly influencing the spatial and temporal distributions of water resources. This is particularly evident in Texas, a rapidly growing state with a pronounced west-east gradient in water supply. This study utilizes Coupled Model Intercomparison Project Phase 6 (CMIP6) data and data-driven methodology to improve projections of Texas's future water resources, focusing on actual evapotranspiration (AET) and water availability through enhanced Multi-Model Ensembles. The results reveal that the data-driven model significantly outperforms the CMIP5 and CMIP6 models across all skill metrics, underscoring the potential of data-driven methodologies in advancing …

A Case For Hope In A Warming World, Noreen L. Herzfeld

Reuter Professorship of Science and Religion Publications

It is difficult to feel hopeful in a rapidly warming world. But hope is not just a feeling. It is an active verb, one that calls for courage, solidarity, a clear vision, and hard work. First, knowing that each fraction of a degree counts, humanity is called not to despair but to use every technology and means, technologies we already have. Second, we can be encouraged by a vision of a new world and society that works for everyone. Third, we can be heartened by nature’s resilience and an evolutionary theology that looks toward the future.

2024 February 15 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

2024 February 8 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Analyzing The Ramifications Of Climate Change On Mental Health, Salvatore A. Medori

CAFE Symposium 2024

When thinking about the vast array of impacts that the climate crisis has on humanity, there are many things that come to mind, but mental health impacts are likely not one of them. Even though research demonstrates that mental effects from any form of disaster far exceed the physical health implications mental health impacts of the largest disaster facing humanity since the Second World War are rarely considered at all, let alone when solutions are being created. This has led to a hidden crisis emerging underneath an even larger crisis, with serious consequences for most individuals across the globe. The …

Sulfate Enhances The Adsorption And Retention Of Cu(Ii) And Zn(Ii) To Dispersed And Aggregated Iron Oxyhydroxide Nanoparticles, Emma M. Kocik, Abigail Kim, Miranda L. Aiken, Lauren Smith, Christopher S. Kim

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The adsorption and retention of metal ions to nanoscale iron (hydr)oxides in aqueous systems is significantly influenced by prevailing environmental conditions. We examined the influence of sulfate, the second most common anion in seawater that is present in many other natural aquatic systems, on the adsorption and retention of Cu(II) and Zn(II) to synthetic iron oxyhydroxide nanoparticles (NPs) and their aggregates. Batch uptake experiments with monodisperse NPs and NPs aggregated by changes in pH, ionic strength, and temperature were conducted over sulfate concentrations ranging from 0 to 0.30 M. The introduction of 0.03 M sulfate significantly increased the initial adsorption …

2024 February 1 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

2024 February - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Trends In Catch Rates Of Sawfish On The Australian North West Shelf, C. Wakefield, S. J. Newman, M. Braccini, A. Harry

Fisheries Research Articles

Northwestern Australia is thought to have some of the world’s last remaining viable sawfish populations, although little quantitative data exists on their status or trends. This study examined 17 years of logbook bycatch records (n = 815) for green sawfish Pristis zijsron and narrow sawfish Anoxypristis cuspidata from a trawl fishery operating on the Australian North West Shelf. Incidental sawfish captures by the fishery are rare, occurring approximately once every 75 trawls (~199 trawl hours). To standardize catch rates and account for excess zeros in the data, we employed generalized additive models for location, scale, and shape (GAMLSSs) using a …

Southern Maine, New Hampshire, And Northern Massachusetts Continental Shelf Geophysical Database: 2022 Field Campaign – Grain Size Data, Station Summaries, And Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Michael Bogonko

Data Catalog

Presented in this data report are the geophysical data collected during a major field campaign in 2022, with the purpose of obtaining ground truth for the expansion and improvement of high-resolution surficial geology maps of the western Gulf of Maine (WGOM) and for the description of reference sites developed for future evaluations of acoustic systems (Ward et al., 2021a; 2021b). Data from the UNH Ocean Engineering 972 Hydrographic Field Course classes in 2021 and 2022 are also included. This expansion of the geophysical database is being used to verify seafloor classifications in previously mapped areas that lack sufficient data, and …

Containerization Of Seafarers In The International Shipping Industry: Contemporary Seamanship, Maritime Social Infrastructures, And Mobility Politics Of Global Logistics, Liang Wu

Dissertations, Theses, and Capstone Projects

This dissertation discusses the mobility politics of container shipping and argues that technological development, political-economic order, and social infrastructure co-produce one another. Containerization, the use of standardized containers to carry cargo across modes of transportation that is said to have revolutionized and globalized international trade since the late 1950s, has served to expand and extend the power of international coalitions of states and corporations to control the movements of commodities (shipments) and labor (seafarers). The advent and development of containerization was driven by a sociotechnical imaginary and international social contract of seamless shipping and cargo flows. In practice, this liberal, …

Analyzing The Effects Of Data Variability & Volume On Predicting Particulate Matter (Pm2.5): Insights From A Machine Learning Approach, Jada A. Macharie

Theses and Dissertations

Accurately predicting PM_2.5 concentrations are imperative to the future of public health and environmental policies. Machine learning models incorporating spatial and temporal datasets to predict PM_2.5 are often limited by data availability constraints and poor resolution satellite imagery.

Effect Of Substrate Temperature And Deposition Power On The Surface Morphology And Optical Properties Of Zno:Mg Thin Films Deposited By Dc Magnetron Sputtering, Saidi Saidi, Margaret E. Samiji, Nuru R. Mlyuka

Tanzania Journal of Science

Magnesium doped zinc oxide (ZnO:Mg) thin films were deposited on soda lime glass slides by DC magnetron sputtering method. Atomic force microscope (AFM), and UV/VIS spectrophotometer were used to investigate the effect of sputtering power and substrate temperature on the surface morphology and optical properties of ZnO:Mg thin films. AFM images revealed that sputtering power and deposition temperature have significant influence on surface morphology of the ZnO:Mg thin films. For all sputtering powers and substrate temperatures investigated, ZnO:Mg films had peak transmittance above 85%. Samples deposited at 110 W sputtering power and 450 °C substrate temperature showed the best peak …

Application Of Remote Sensing And Spectroradiometry In Geological Mapping: A Case Study Of Handeni (Qds 148) Block, Eastern Mozambique Belt, Tanzania, Masota M. Magigita, Elisante Mshiu, Cassy Mtelela

Tanzania Journal of Science

This study applies remote sensing (RS) as a geologic mapping aid tool , using Handeni Block of Tanzania as a case study. To achieve the objective of this study, we have utilized various RS processing and image enhancement techniques on multispectral data, including ASTER, Landsat 5, Landsat 8, and Sentinel 2A. The method proved successful whereby both Landsat-5-data with band combination (BC) 7:4:2 and 7:5:4 and band ratio (BR) 5/3:5/1:7/5 and Landsat-8 data with BCs 5:6:7 and 7:6:4 mapped out marble units. Sentinel 2A data (with BC 8:11:3, BRs 12/2:11/2:8/11; 12/4:11/3:11/2 and 12/4:12/2:11/3) together with image enhancement decorrelation stretch on …

Quantifying The Strength Of The El Niño Southern Oscillation And The Indian Ocean Dipole In Influencing The Ond Rainfall Season In Tanzania, Benjamin William Ongito, Paul T.S. Limbu

Tanzania Journal of Science

The current paper examines the strength of variability between the El Niño-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) in influencing October to December (OND) rainfall over the bimodal rainfall regime of Tanzania. The empirical orthogonal function (EOF), correlation analysis, and composite analysis were used during the data analysis. The results show more rainfall distribution over the western part of the Lake Victoria basin and to the peripheral of the northern coast of the country, thus suggesting that, during the OND rainfall season, the onset starts in the western part of the Lake Victoria basin, then spreads to the …

Water Whiplash In Mediterranean Regions Of The World, Citlalli Madrigal, Rama Bedri, Thomas Piechota, Wenzhao Li, Glenn Tootle, Hesham El-Askary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The presence of weather and water whiplash in Mediterranean regions of the world is analyzed using historical streamflow records from 1926 to 2023, depending on the region. Streamflow from the United States (California), Italy, Australia, Chile, and South Africa is analyzed using publicly available databases. Water whiplash—or the rapid shift of wet and dry periods—are compared. Wet and dry periods are defined based on annual deviations from the historical record average, and whiplash occurs when there is an abrupt change that overcomes an accommodated deficit or surplus. Of all the stations, there are more dry years (56%) than wet years …

The Effects Of Wildfire Aerosol Emissions On Air Quality, Emma Braun, Audrey Shirley

The Journal of Purdue Undergraduate Research

No abstract provided.