Oceanography and Atmospheric Sciences and Meteorology Commons^™

Characterizing The Unique Chemical Imprint Of On-Axis, Lower-Temperature Hydrothermal Flow To The Deep Ocean (Southern East Pacific Rise, 16.5°–18.0°S), Laura E. Moore, Randelle M. Bundy, Joseph A. Resing, Scott M. White, Tamara Baumberger, Peter N. Sedwick, Nathaniel J. Buck, Anson M. Antriasian, Isaac Keohane

Faculty Publications

In addition to high-temperature vents, lower-temperature flow (LTF) (< 300°C) is abundant along mid-ocean ridges and contributes globally-important fluxes of heat and water along with largely-unconstrained geochemical influences on the ocean. We examined the impact of on-axis LTF on the chemical composition of the overlying water column (< 40 m above seafloor) along the 16.5°–18.0°S sector of the ultrafast-spreading southern East Pacific Rise using autonomous underwater vehicle Sentry surveys and conductivity-temperature-depth rosette casts. LTF sites were typically spatially isolated from high-temperature systems and imparted unique chemical signatures to the overlying ocean. Water column samples impacted by LTF exhibited low particulate iron:sulfur ratios and high methane: total-dissolvable manganese ratios, whereas samples influenced by high-temperature venting exhibited opposite trends. We confirmed that LTF imparts a distinct and measurable chemical signature to the water column, independent from high-temperature vents. Isolated, on-axis LTF will be important to consider when assessing hydrothermal circulation impacts upon ocean biogeochemistry.

2026 April 16 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Climate Change And Transportation, Paul J. Marchese

Open Educational Resources

This module examines how climate change is affecting transportation systems across multiple sectors, including roads, rail, air, maritime, and active transportation. It highlights key climate trends such as rising temperatures, sea level rise, and extreme weather, and explains how these factors disrupt infrastructure, operations, and safety. The module also explores the economic, operational, and policy challenges associated with maintaining resilient transportation systems under changing environmental conditions. Finally, it presents a range of adaptation and mitigation strategies, emphasizing engineering solutions, sustainable technologies, and data-driven decision-making.

Prediction Of Future Mushroom Fruiting Success And Dispersion Based On Models Of Changing Surface Air Temperature In Oaxaca, Mexico, Frida Martinez

ATU Scholars Symposium

Mushrooms serve various purposes, including medicinal, culinary, and cultural significance for indigenous groups, as well as recreational and ecosystem services. Oaxaca, Mexico, is a hotspot for mushroom biodiversity including the following varieties: Amanita muscaria, Schizophyllum commune and Coprinellus disseminates. The purpose of this study is to determine if a changing Mean Surface Air Temperature will have an influence on these mushrooms. We obtained, analyzed, and compared historical and future climate data from the World Bank Group Climate Change Knowledge Portal to identify if any of the mushroom species would be impacted. The study revealed a general trend of warming Mean …

Assessing The Effect Of A Human-Made Reservoir On The Mussel Community In Caney Creek, Trakker Estes

ATU Scholars Symposium

Freshwater mussels are one of the most threatened taxonomic groups globally, with less than 32% of North American taxa considered secure. In Arkansas, over half of the state’s 85 species are endangered, threatened, or of special concern. Small impoundments may contribute to these declines through reduced hydrological connectivity and the resulting decline of fish community movement. This study examines the effects of Tri-County Lake, a small impoundment of Caney Creek in southern Arkansas, on mussel abundance and diversity. In total, eight sites were surveyed upstream, within, and downstream of the impoundment across various habitat types. A timed-search approach utilizing scuba …

2026 April 9 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Regional Drought Modulation By Enso And Iod As Indicated By The Standardized Precipitation Index, Arpit Tiwari, Preethi Nanjundan, Tanu Sharma, Ravi Ranjan Kumar, Satyaban Bishoyi Ratna

Northeast Journal of Complex Systems (NEJCS)

Understanding the modulation of drought by large-scale ocean–atmosphere teleconnections is crucial for strengthening drought prediction and resilience in India. This study investigates the influence of the El Niño–Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) on meteorological drought characteristics across India from 1950 to 2024 using the Standardized Precipitation Index (SPI) at a 12-month timescale. Drought events were quantified in terms of frequency, duration, severity, and intensity and linked to ENSO–IOD variability through composite, correlation, and mediation analyses. Results reveal that El Niño events consistently correspond to widespread and severe droughts, particularly over central and southern India, with drought …

Bgc-Argo Float Reveals Shifts In Nitrogen-Carbon Cycling In An Oxygen-Deficient Zone, Mariana B. Bif, Colette Kelly, Mark A. Altabet, Annie Bourbonnais, Claire Elbon, Edgart Flores, Alanna Mnich, Josh Plant, Kenneth S. Johnson

Faculty Publications

Oxygen-deficient zones are hotspots of marine fixed nitrogen loss, but the temporal dynamics of their microbial processes remain poorly resolved. Here we present a nearly three-year high-resolution record from a Biogeochemical Argo float in the Eastern Tropical North Pacific that captures a decline in nitrite concentrations, reflecting a shift in nitrogen redox balance. Using a stoichiometric mass-balance model, we quantify nitrogen transformations, including dissimilatory nitrate reduction to nitrite, denitrification, anammox, and nitrite oxidation, and their coupling to carbonate chemistry. The model shows that dissimilatory nitrate reduction to nitrite dominates nitrogen transformations, while denitrification and anammox vary over depth, biogeochemical transition, …

Preliminary Sonification Of Enso Using Traditional Javanese Gamelan Scales, Sandy Hs Herho, Rusmawan Suwarman, Nurjanna J. Trilaksono, Iwan P. Anwar, Faiz R. Fajary

Northeast Journal of Complex Systems (NEJCS)

Sonification—the mapping of data to non-speech audio—offers an underexplored channel for representing complex dynamical systems. We treat El Niño-Southern Oscillation (ENSO), a canonical example of low-dimensional climate chaos, as a test case for culturally-situated sonification evaluated through complex systems diagnostics. Using parameter-mapping sonification of the Niño 3.4 sea surface temperature anomaly index (1870–2024), we encode ENSO variability into two traditional Javanese gamelan pentatonic systems (pelog and slendro) across four composition strategies, then analyze the resulting audio as trajectories in a two- dimensional acoustic phase space. Recurrence-based diagnostics, convex hull ge- ometry, and coupling analysis reveal that the sonification …

2026 April 2 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Fear In The Forecast: Do You Believe The Government Controls The Weather?, Gabriella Bartsch

Honors Papers and Posters

Weather manipulation by the government is among the most widely believed conspiracy theories in America, with over 49 percent of Americans subscribing to this belief. As belief in weather-related conspiracies continues to gain traction, understanding the political and social factors that drive these beliefs becomes increasingly essential. In this study, data from the Chapman Survey of American Fears, a representative national sample of U.S. adults, as well as a qualitative content analysis of X/Twitter posts from 2020 to 2026, are used. This research examines how political partisanship and conspiratorial predisposition are reflected in media consumption and levels of institutional trust, …

Developing A Multi-Band Gnss Remote Sensing Station To Measure Precipitable Water Vapor For Flash Flood Nowcasting, Madison Gleydura

Doctoral Dissertations and Master's Theses

Flash flood nowcasting in Central and Southern Appalachia is particularly challenging due to steep terrain, narrow valleys, highly localized rainfall patterns, and limited measurement coverage. Traditional remote sensing methods, such as Doppler radar and microwave radiometry, suffer from reduced resolution at long range and signal blockage by mountains. GNSS-meteorology offers an established alternative for measuring precipitable water vapor and is currently integrated into several numerical weather models. Recent research demonstrates that commercial-grade GNSS receivers can produce tropospheric products comparable to those from geodetic-grade equipment. The gaps in mountain coverage can be addressed by developing a low-cost, self-contained embedded system that …

Revisiting The Hydrostatic Assumption In The Marine Atmospheric Surface Layer, Karina Griffin

Honors Theses

The marine atmospheric surface layer (MASL), defined as the lowest ~100 m of the atmosphere overlying the ocean, is a complicated environment influenced by air-sea interactions and regional  weather patterns. In the absence of air motion, air pressure in the MASL decreases with altitude at  a constant rate due to the reduction in weight of the overlying air column. This relationship is  defined by a linear hydrostatic equation and is applied under the assumption that any dynamic  vertical pressure gradients will be small relative to the hydrostatic pressure gradient. The  hydrostatic assumption is commonly applied in the MASL despite the …

Impact Of In Situ Observations From Three Torus Cases On Model Analyses And Forecasts Of Severe Convection, Robert M. Szot

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The quality of forecasts of severe deep convection in high-resolution numerical weather prediction is dependent on the representativeness of the model initial conditions. This representativeness may be negatively impacted by limited observation availability and by the presence of mesoscale heterogeneities that were not detected by conventional observations assimilated into convection-allowing models. By assimilating storm-scale observations from the Targeted Observation by Radars and Uncrewed Aircraft Systems (UAS) of Supercells (TORUS) campaign into an ensemble styled after the Warn-on-Forecast System, this study aims to investigate if data from field work platforms can improve the quality of initial conditions in the ensemble, potentially …

Development And Evaluation Of An Mpas-Based Urban Modeling System For The New York City Region, Marco S. Yu, Kristian Rice

Publications and Research

Complex geometry and varying land cover make urban environments difficult to simulate accurately. This research presents a performance evaluation of the newly developed urban modeling system in the Model for Prediction Across Scales (MPAS). Weather over the New York metropolitan area during June 2018 was simulated using supercomputing resources and the new urban modeling system. Modeled 2-m air temperature was compared with historical hourly observations from five NYC Mesonet stations, one located in each of the five boroughs. Comparison showed that the model follows the timing of warming and cooling well, but overestimates the magnitude of temperature swings at peaks …

2026 April - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All,

The main story of April 2026 was the hot and dry pattern that impacted Tennessee for most of the month and which was a continuation of this same pattern from March. Temperature anomalies across the state in April were slightly less than what we observed in March, but mean temperatures still ranged from 4-8°F above normal for April. Based on mean temperatures for the month, April 2026 was the warmest April on record in Knoxville’s 153-year weather history (beating out April 2017 by 0.2°F) and Nashville’s 152-year weather history (beating out April 2017 by 1.2°F). April 2026 was …

2026 April - Tennessee Climate Snapshot, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

Upper Ocean Cycling Of Iron South Of The Polar Front: Biological Patterns And Processes, Luis M. Laglera, Santos-Echeandía, Viena Puigcorbé, Christine Klass, Dieter Wolf-Gladrow

Research outputs 2022 to 2026

Samples from the upper 300 m along the 52°S band, south of the Antarctic Polar Front in the Atlantic sector of the Southern Ocean, including a 3-week monitoring of a persistent bloom, were analyzed to advance our understanding of iron cycling and supply to recurrent phytoplankton blooms. We measured dissolved Fe (dFe, <0.2 μm) and labile particulate iron using a mild acid leach (pLFe^48h) targeting primarily detrital and fecal material. Particulate iron was partitioned into size classes to distinguish small, “slow” sinking particles (<53 μm) from large, “fast” sinking particles (>53 μm), while intermediate fractions were analyzed to investigate aggregation and export processes. Across all stations, dFe exhibited a consistent vertical structure, including a previously undescribed …

Projections Of The Characteristics Of Extreme Precipitation In East Africa Using Bias-Corrected Cmip6 Models, Exavery K. Makula

Tanzania Journal of Science

In the context of ongoing global climate change, the intensification of the hydrological cycle is expected to modify the frequency, magnitude, and spatial distribution of extreme precipitation events. Understanding how precipitation extremes will evolve under climate change is critical for East Africa (EA), a region highly vulnerable to hydroclimatic hazards and strongly dependent on rainfall-driven socioeconomic systems. The region experiences two main rainfall seasons, namely the long rains (March-May, MAM) and the short rains (October-December, OND). This study investigates future projections of the characteristics of extreme precipitation across the EA using an ensemble of biascorrected CMIP6 global climate models. Extreme …

Norfolk Flooding And Its Effect On Nutrient And Enterococcus Levels, Malachi R. Stephens

Knowledge and Creativity Expo

Tidal flooding is common in the City of Norfolk, VA due to high rates of sea rise in the region, as well as the region’s subsidence. This has led to increases in flooding at high tide, especially during the spring tide portion of the tidal cycle.  At high tide water from the Elizabeth and Lafayette Rivers can flood the landscape directly or can rise out of storm drains. This floodwater often stays on land for long periods of time and can deliver contaminants back into the rivers. To determine the amounts of nutrients and Enterococcus, a fecal indicator, delivered to …