Oceanography and Atmospheric Sciences and Meteorology Commons^™

The Role Of Enso Diversity In Modulating Tornadic Activity In The United States, Davis Boyd Newton

Theses and Dissertations

Tornado activity in the United States is influenced by large-scale climate patterns, especially by the El Niño-Southern Oscillation (ENSO). While prior research has explored ENSO’s impact on severe weather, the influence of ENSO flavors, Central Pacific (CP) and Eastern Pacific (EP), on tornadic activity remains understudied. Using tornado records, reanalysis data, and sea surface temperature anomalies, we assess how convective available potential energy (CAPE), wind shear, and jet stream dynamics influence tornado frequency and distribution. Results indicate that CP La Niña years had significant increases in tornado frequency, particularly across the Midwest, Central Plains, and Southeast. EP ENSO years had …

Integrating Case Studies With Meteorologists’ Insight: Assessing Meteorologists’ Perception And Utilization Of Composite Indices, Brianna Marie Salazar

Theses and Dissertations

Meteorologists from sectors, including broadcast, academia, and operations, use derived composite indices such as 0-1km and 0-3km energy helicity index (EHI), effective-layer supercell composite parameter (SCP), fixed-layer and effective layer significant tornado parameter (STP), in addition to other resources, when developing severe local storm forecasts. This study utilizes the Weather Research and Forecasting (WRF) model to create simulations of composite indices for two tornado-producing events: 31 March 2023 and 3 May 1999. With modifications to geographical location, these simulated scenarios are then utilized in the survey to gauge how meteorologists assess where tornado potential is highest. Additionally, a combination of …

Evaluating Rainfall Sensitivity Over Land To Tropical Cyclone Parameters Using Idealized Wrf, Madison C. Yawn

Theses and Dissertations

Tropical cyclones (TCs) are extreme weather events impacting the United States nearly every year. These events often cause severe damage due to the associated responses they produce including storm surge and rainfall, and the accurate estimation of these TC hazards is necessary to support coastal engineering, risk assessment, and emergency management activities. Evaluating TC-driven hazards is often done in combination with numerical models to simulate how environmental interactions alter the physical processes and responses of these storms. The purpose of this study was to simulate synthetic TC events using the Advanced Weather Research and Forecasting (WRF) model to understand how …

2025 May 15 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Dry And Wet Deposition Of Atmospheric Microplastics In Las Vegas, Nevada, Laine Adame

UNLV Theses, Dissertations, Professional Papers, and Capstones

Plastics have been one of the most widely used man-made materials since their inception, and production is expected to grow by five percent every year. Plastic waste has become a growing global environmental issue. Primary MPs are plastics that are created to be intentionally tiny for their specific functional purpose. Secondary microplastics (MPs) are byproducts of plastic waste occurring due to the breakdown of larger plastics resulting in the presence and accumulation of MPs in the environment. MPs are defined as tiny particles of plastic between 5 mm and 1 μm in size. MPs have been found in the deep …

Advancements In Solar Energy Life Cycle Assessment And Implications For Power Plants In The Western Us, Santiago Cisneros Castillo

UNLV Theses, Dissertations, Professional Papers, and Capstones

New solar energy technologies, such as second-generation photovoltaic panels, are increasingly being installed at utility scale. Our accounting of the life cycle climate change impacts or carbon footprint of solar power technologies needs to be revised as technologies change and as prior omissions of related impacts are identified. This thesis aims to update the life cycle climate change impacts of two solar energy technologies. First, the direct land use change (DLUC) and albedo change impacts from removing native vegetation and installing CSP troughs were incorporated into life cycle assessment (LCA) scenarios for the four currently operational CSP trough power plants …

Evaluation Of Topographic Effect Parameterizations In Weather Research And Forecasting Model Over Complex Mountainous Terrain In Wildfire-Prone Regions, Yonghan Jo, Seung Hee Kim, Yungon Lee, Changki Kim, Jinkyu Hong, Junhong Lee, Keunchang Jang

Institute for ECHO Articles and Research

Recent trends of intense forest fires in the Korean Peninsula have increased concerns about more extreme burning in the future under a warming climate. Accurate and reliable fire weather information has become more critical to reduce the risk of forest-related disasters over complex terrain. In this study, two parameterizations reflecting complex topographic effects were implemented in the Weather Research and Forecasting (WRF) model. The model performance was evaluated over the mountainous region in Gangwon-do, South Korea’s most significant forest area. The simulation results of the wildfire case in 2019 show that subgrid-scale orographic parameterization considerably improves model performance regarding wind …

Patterns In Tropical Cyclone Intensity And Frequency Since 1960, Ramie E. Thompson

Student Scholarship

Tropical cyclones, also known as hurricanes or typhoons, are defined as organized storm systems that form in the warm waters around the equator (NOAA, 2024). This happens due to the combination of warm waters, light winds, and preexisting weather conditions. In the last 50 years, tropical cyclones have accounted for approximately 800,000 deaths and an economic loss of $1.4 trillion USD due to their resulting damages (WMO, 2024). Research in this field includes studies that encompass a variety of time scales including from 85 to 150 years on a global or regional level and studies that focus on more recent …

Climate Constrains The Enhancement Of Co2 Fertilization On Forest Gross Primary Productivity, Xinyuan Wei, Daniel J. Hayes, Christopher R. Schwalm, Joshua B. Fisher, Deborah N. Huntzinger, Lei Ma, Rodrigo Vargas, Nathaniel A. Brunsell

Mathematics, Physics, and Computer Science Faculty Articles and Research

Forest gross primary production (GPP) is influenced by the interplay between climate conditions and atmospheric CO₂ levels, which interact in complex ways, generating both compensating and amplifying effects. In this study, eddy covariance flux measurements from 50 forest ecosystems were integrated with simulations from 14 terrestrial biosphere models to investigate how climate conditions and atmospheric CO₂ concentrations regulate forest GPP. This approach bridges site-level observations with biome-scale model estimates to develop a global understanding. Our findings suggest that in boreal and cold temperate regions, temperature primarily constrains the enhancement of the CO₂ fertilization on forest GPP; however, …

Interpreting Spatial And Temporal Variations In Global Air Quality Using A Chemical Transport Modeling Framework, Deepangsu Chatterjee

McKelvey School of Engineering Graduate Student Theses & Dissertations

Air quality is a major health concern. Exposure to fine particulate matter (PM2.5) and nitrogen oxides (NOx = NO + NO2) is a leading mortality risk factor across the world. Numerous cohort studies conducted over the past two decades have identified strong associations between ambient air pollution and human mortality, highlighting the adverse health effects of PM2.5 and NO2 exposure. My thesis includes three studies that contribute to a better understanding of air quality. In many regions, including South Asia, elevated emissions from various sectors and sparse ground monitoring are significant challenges. The concurrent development and use of the high-performance …

Diel Patterns Of Biogeochemical Indicators In Tidally-Dominated Creeks, Juliana Calderone

Honors Theses

Marshes and swashes are vital environments as a controlling barrier between land affected by various pollutants and the ocean. Eutrophication and the effects of this process can be detrimental for the areas experiencing it. I am interested in ways areas that have little contact with human interactions compare to areas that are heavily urbanized, and whether either of these locations is at a higher risk for eutrophication. Using spectrophotometry and fluorometry, I analyzed samples collected from the relatively undeveloped and restricted-access locations of Waities Island Beach and Dunn Sound monthly for dissolved nutrients, and chlorophyll. At the time of sampling, …

2025 May 8 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Monitoring Mangrove Dynamics And Evaluating Future Afforestation Potential In The Egyptian Red Sea, Rasha M. Abou Samra, Mansour Almazroui, Wenzhao Li, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Mangrove forests are vital for ecosystem services and coastal management but face stressors from anthropogenic activities and climate change. This study estimates the extent and afforestation potential of mangroves along the Egyptian Red Sea coast from 1984 to 2022 using NDVI derived from Landsat-5 and Sentinel-2 data in Google Earth Engine. Aboveground biomass (AGB), belowground biomass (BGB), carbon (C) stock, and CO₂ sequestration potential were evaluated using Sentinel-2 and elevation data. Future afforestation suitability (2020–2050) under SSP2-4.5 and SSP5-8.5 scenarios was assessed with the MaxEnt model. Mangrove area increased from 0.95 km² in 1984 to 1.46 km^{2 …}

Microplastic Concentrations Within The Winyah Bay River Plume, Daniel C. Haughie

Honors Theses

In the last 20 years, microplastics have become a significant concern for ecosystem and public health. The buoyancy and method of introduction makes river plumes a likely repository for microplastic accumulation. A river plume is a bulge of fresher water that expands radially from the mouth of an estuary, with distinct lines called fronts at the leading edge of the plume. A front is a region of convergence between the fresher plume water and the saltier ocean water. The density differences between the two water masses may create an easily identifiable color and salinity gradient. These fronts often allow for …

Marine Heat Waves Effects On Rocky Intertidal Ecosystem Functioning, Skyler Peterson, S. Schneider, C.L. Webb, A. Leighton

Undergraduate Research Symposium Posters

Severe heat waves may cause long-term changes in marine ecosystems and are expected to increase in magnitude and frequency. Here we use surveys from six localities across a six-year interval (2013-2019) to investigate the effects of heat waves on the functional diversity of rocky intertidal ecosystems (Vancouver Island, Canada).

Functional diversity, the number and types of functions performed by organisms, influences ecosystem stability and health. To assess changes in functional diversity we used analyses of biological traits. Biological traits are measurable properties of organisms that describe their morphology, physiology, and behavior. We quantitatively assessed changes in functional diversity in response …

Western Australia’S Marine Heatwave Update - 9th May 2025, Department Of Primary Industries And Regional Development, Western Australia

Marine Heatwave Notification Reports

Category 1 – Moderate marine heatwave (MHW) conditions continue for the Gascoyne and South Coast Bioregions. Marine heatwave conditions in the North Coast Bioregion have abated and the West Coast Bioregion remains warm but neither are categorised as experiencing MHW conditions.

2025 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All,

For May 2025, the main weather/climate stories were the continued pattern of severe weather impacting Tennessee as well as Chattanooga recording their wettest May in the 147-year weather history of the city. Starting with the record rainfall in Chattanooga, the Chattanooga airport weather station recorded a total of 12.02-inches of rainfall over May 2025, 8.08-inches above normal and 0.02-inches above the previous record wettest May in 1929. Many other areas of East Tennessee and the Cumberland Plateau also had well above normal rainfall this month, but they were emerging out of a drought from last fall and winter …

2025 May 1 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

The Influence Of Complex Terrain On The Turin, New York Tornado Of 2023, Alex D. Kramer

Atmospheric and Environmental Sciences Honors Program

Although uncommon as compared to other regions of the United States, the Northeast does experience significant tornados; those rated F/EF3 and above, of which some have had profound impacts on the region. Due to the diverse topography of the region, including its many northsouth oriented river valleys, most of these significant tornados traversed considerable changes in elevation throughout their lifetime. This study seeks to better understand the impacts of local topography on the intensity and overall progression of a significant tornadic event through using the most recent Northeast EF3: the Turin, NY tornado. With the consideration of previous studies involving …

Assessment Of Sampling Gears For Bigheaded Carp In Mid-Order Prairie Rivers In Nebraska, Brett M. Anderson

School of Natural Resources: Dissertations, Theses, and Student Research

Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis (collectively bigheaded carp) have invaded tributaries to the Missouri River and Platte River in Nebraska, USA. Information pertaining to efficient sampling protocols for assessing bigheaded carp populations as well as benefiting removal efforts is needed. Herding is a method used to increase the capture efficiency and detection probability of adult bigheaded carp by simultaneously using active and passive sampling gears. During June-July 2023, four herding techniques were assessed regarding their ability to elicit directional movement past an enclosure gate. The combination of sound and electrofishing resulted in the highest mean …