Oceanography and Atmospheric Sciences and Meteorology Commons^™

Evaluating The Long-Term Effectiveness Of Marsh Terracing For Conservation With Integrated Geospatial And Wetland Simulation Modeling, Nick Carpenter, Laura Costadone, Thomas R. Allen

ODU Articles

Coastal marshes provide essential ecosystem services, yet they are vulnerable to anthropogenic stressors and climate change, particularly sea level rise (SLR). Restoration approaches like marsh terracing have emerged as nature-based strategies to enhance resilience and reduce habitat loss. This study applies the Sea Level Affecting Marshes Model (SLAMM) to assess the potential of marsh terraces to mitigate future losses, while also examining the model’s limitations, including its assumptions and capacity to reflect complex marsh processes. A geospatial approach was used to generate 3D representations of terraces through morphostatic modeling within digital elevation models (DEMs). Under a no-restoration scenario, SLAMM projections …

High-Resolution Modeling Of Extreme Heat Events With Socioeconomic Consideration: A Real-Case Wrf-Les Approach, Maryam Golbazi, Frank Liu, Yin-Hsuen Chen, Timothy W. Juliano, Heather Richter

ODU Articles

The overarching goals of this work is to explore best practices for micro-scale modeling of a real case, identify relevant phenomena by using high-resolution modeling, and to explore their implications for public health, and climate resilience strategies in Hampton Roads, VA, USA. This project employs the Weather Research and Forecasting (WRF) model to conduct a comprehensive study of Hampton Roads, utilizing a coupled mesoscale to microscale modeling capable of resolving boundary layer turbulence. This study has three primary objectives: (1) to establish the optimal mesoscale to Large-Eddy Simulation (LES) configurations for complex geographical regions such as the Hampton Roads (HR) …

Metabarcoding-Biomass Relationships And Internal Standards For Quantitative Dna Metabarcoding, Frances Webber

Open Access Master's Theses

DNA metabarcoding has been widely adopted due to its power in investigating the composition of protistan communities, accurately identifying even small and cryptic taxa. However, the compositional nature of DNA metabarcoding results, and the distortion of natural abundances due to variation of the often-used 18S rRNA gene copy number over several orders of magnitude, renders these results semi-quantitative at best, limiting the application of DNA metabarcoding to ecological study. Here, we constructed mock communities from uni-algal cultures of taxonomically diverse phytoplankton and conducted metabarcoding using multiple primer sets and both DNA and cDNA as PCR templates. For each culture, chlorophyll …

High-Altitude Balloon-Launched Uncrewed Aircraft System Measurements Of Atmospheric Turbulence And Qualitative Comparison With Infrasound Microphone Response, Anisa Haghighi

Theses and Dissertations--Mechanical and Aerospace Engineering

This study explores the use of a balloon-launched uncrewed aircraft system (UAS) to measure atmospheric turbulence in the troposphere and lower stratosphere using both wind velocity measurements and infrasonic acoustic energy. The UAS, a glider configured for autonomous descent along a predefined trajectory, had on board, in situ sensors to capture thermodynamic and kinematic atmospheric parameters. Additionally, it carried an infrasonic microphone to evaluate its potential for remotely detecting clear-air turbulence by capturing infrasonic waves. The system’s performance was assessed over the course of three test flights conducted in New Mexico, USA, in 2021. The descent enabled high-resolution profiling, with …

Analyzing Seasonal Wind Trends And Climate Change Impacts Along The East Coast Of The United States (1990-2022), Avery L. Wilson

Honors Theses and Capstones

This study investigates long-term trends in ocean wind intensity and variability along the U.S. East Coast between 1990 and 2022 using ECMWF ERA5 reanalysis data. Focusing on monthly maximum, mean, and standard deviation (STD) of wind speed at 10 meters above the surface, linear regressions were performed to analyze long-term trends. Results indicate a significant increase in wind intensity and variability in the northeastern region, particularly during winter months, which may forecast more frequent and intense cyclonic activity such as Nor’easters. Conversely, a weak decreasing trend was observed in the south. These shifts have implications for ocean-atmosphere dynamics, including vertical …

Quantifying Links Between Phytoplankton Physiology And The Environment, Gabrielle M. Armin

Open Access Dissertations

Phytoplankton are microscopic, primary producers in aquatic ecosystems worldwide. They are key links in global biogeochemical cycles, converting inorganic compounds into bioavailable nutrients which fuel fisheries. Through photosynthesis, phytoplankton play an essential role in the carbon cycle and marine biological pump, drawing carbon from the atmosphere, which is eventually sequestered in the oceans, regulating our Earth’s climate. Due to their influential role in large scale processes, there have been many efforts to characterize and quantify phytoplankton impacts to ecosystem health and global nutrient cycles. Often, phytoplankton physiology has been highly simplified in global or ecosystem models, limiting their representation to …

Numerical Modeling Study Of Coastal Impacts From Extreme Storms And Sea Level Rise In Southern New England, Deborah Crowley

Open Access Dissertations

Coastal areas in southern New England are vulnerable to a range of impacts from extreme storms and sea level rise. The most frequent extreme storms are extratropical storms, commonly referred to as nor’easters, named for the direction of the strongest winds, though these storms also have strong winds from other directions.

Storm winds generate large waves and push water up along the coast in the form of storm surge. The combined impacts of increased water levels and waves include flooding and morphological change. Sea level rise (SLR) will exacerbate these processes, amplifying the associated impacts, which may pose increasing threats …

A Socio-Ecological Investigation Of Ulithian Spearfishing, Joshua Pi

Open Access Dissertations

Coral reef socio-ecological systems (SESs) characterize the interconnected relationships between coral reef ecosystems and reef-dependent communities. One such SES exists in Ulithi Atoll, Federated States of Micronesia, where Ulithians fish, steward, and govern their reefs through customary marine tenure, traditional ecological knowledge, and cultural taboos. In recent decades, rapid modernization in Ulithi has introduced new fishing technologies, transformed fishing practices, and ultimately reshaped the functioning of Ulithi’s traditional SES. One significant change was the introduction of spearfishing during the mid-20^th century, which is more selective and individualistic compared to other community-centric fishing methods that have existed for generations. This …

Incorporating Time-Varying Parameters And Climate Drivers Into Fisheries Models, Rachel Catherine Marshall

Open Access Dissertations

Commercial fishing is a highly valuable industry in the United States and globally, and as such, managing based on the best available science is necessary to maintain important fish stocks. Some parameters in stock assessment models that are assumed to be constant over age and time may actually vary to an extent that stock assessment modeling results could be improved by allowing the parameters to vary in the models. In the present dissertation, two stock assessment parameters that are typically held constant are explored for potential time or age variance. Potential environmental drivers of nonstationary parameters are also explored. Productivity, …

Coupled Numerical Modeling Of Wave-Current Interactions In Tropical Cyclones, Angelos Papandreou

Open Access Dissertations

This Ph.D. dissertation presents a numerical modeling study of wave-current interactions in tropical cyclones. Chapter 1 focuses on wave-current interaction in shallow water during hurricane landfall, when strong winds often generate severe storm surges that dramatically raise water levels and cause significant damage to human lives and property. Large waves generated by these winds further amplify storm surges, making it necessary to couple storm surge models with wave prediction models. Currently, two-dimensional coupled storm surge-wave models incorporate the effect of waves on the storm surge through the forcing of radiation stress gradients. However, recent studies on wave-current interactions indicate that …

Comparing Surface Currents Near The Mouth Of Three Bays Along The U.S. East Coast: Chesapeake Bay, Delaware Bay, And New York Bay, Tal Ezer, Teresa Updyke

CCPO Publications

Monthly surface currents at 2 km resolution near the mouths of three U.S. east coast bays were obtained from high-frequency radars (Coastal Ocean Dynamics Application Radar, CODAR) during 2012–2024. The currents near these bays, the Chesapeake Bay (CB), the Delaware Bay (DB) and the New York Bay (NB) were analyzed to infer similarity and differences, as well as potential common forcing from regional and basin-scale factors. The contribution to flow variability from local and remote forcing is evaluated by comparing surface currents with (a) river discharges into each bay, (b) with local and regional winds, and (c) with the North …

Surface Currents In The Mid-Atlantic Bight: The Role Of The Gulf Stream Versus Wind, Tal Ezer

CCPO Publications

Surface currents of the Mid-Atlantic Bight (MAB) were studied using high frequency radar (HFR) observations at 6 km resolution during a five-year period (2020-2024). The study's focus on the role of the Gulf Stream (GS) contrasts with most past studies that focused on the seasonal wind-driven currents. Empirical Orthogonal Function (EOF) analyses of the daily HFR currents were conducted with and without the GS, revealing modes of current variability linked to the seasonal wind pattern and storms versus modes linked to GS variability. The remote impact of the GS on coastal currents is complex, with different impacts seen on different …

Multi-Model Estimate Of Antarctic Ice-Shelf Basal Mass Budget And Ocean Drivers, Benjamin K. Galton-Fenzi, Richard Porter-Smith, Sue Cook, Eva Cougnon, David E. Gwyther, Wilma G. C. Huneke, Madelaine G. Rosevear, Xylar Asay-Davis, Fabio Boeira Dias, Michael S. Dinniman, David Holland, Kazuya Kusahara, Kaitlin A. Naughten, Keith W. Nicholls, Charles Pelletier, Ole Richter, Hélène Seroussi, Ralph Timmerman

CCPO Publications

Societal adaptation to rising sea levels requires robust projections of the Antarctic Ice Sheet's retreat, particularly due to ocean-driven basal melting of its fringing ice shelves. Recent advances in ocean models that simulate ice-shelf melting offer an opportunity to reduce uncertainties in ice–ocean interactions. Here, we compare several community-contributed, circum-Antarctic ocean simulations to highlight inter-model differences, evaluate agreement with satellite-derived melt rates, and examine underlying physical processes. All but one simulation use a melting formulation depending on both thermal driving (T^⋆) and friction velocity (u^⋆), which together represent the thermal and ocean current forcings at the …

Mangroves: A Lesson On Modeling Changing Shorelines, Willa Skye

ENGS 15.11: Design and Education

This lesson is an overview of storm barriers, specifically mangroves and how they maintain shorelines. It is meant to offer a visual experience of coastline protection and provide a background for deeper understanding about intertidal zones and their conservation. Students will spend time creating a solution to a flooding problem by making a mock coast and storm barrier. To wrap-up the lesson, students will pair up, then reflect on their model and then individually write or draw their takeaways.

Spatiotemporal Evolution Of Surface Water Quality And Driving Factors Across Varying Levels Of Human Interference In A Major Subbasin Of The Yellow River Basin, China, Longmei Xie, Ruizhong Gao, Xixi Wang, Limin Duan, Lijing Fang, Hui Tong, Chang Yue, Tingxi Liu

Civil & Environmental Engineering Faculty Publications

Study region

The Dahei River Basin, a sub-basin of the Yellow River Basin, was selected for this study. Encompassing population centers and villages in Inner Mongolia, it supports vital ecosystems and underscores the need to address its unique challenges in water management and protection.

Study focus

This study examines surface water quality dynamics in the Dahei River Basin, a key aspect of sustainable water management. Predicting spatiotemporal variations and driving factors remains challenging. Using 2013–2023 datasets on water quality, hydrology, and meteorology, the composite pollution index (CPI), ANOVA, and generalized additive models were applied to provide insights for effective management. …

Using Post-Supercritical Co2-Assisted Method To Deposit Niep Alloy Coating On The Micro-Arc Oxidation Layer Of Az31 Magnesium Alloy And Its Corrosion Behavior Analysis, Kang-Yu Liao, Hung-Hua Sheu, Ming-Yuan Lin, Ming-Chih Kuo, Po-Hsun Wu, Hung-Bin Lee

Journal of Marine Science and Technology–Taiwan

In this study, a Ni-P alloy coating was deposited on the micro arc oxidation (MAO) layer of AZ31 magnesium alloy to improve its corrosion resistance. The MAO layers were prepared under different operated voltages from 300 to 400 V. The results indicated that the optimize operated parameters for MAO layer is at 350 V, the MAO coatings had the most compact microstructure and superior corrosion resistance. In order to improve the corrosion resistance of MAO coating, this study chose to deposit Ni-P alloy coating on the surface of MAO coating via the post supercritical CO₂-assisted electroless plating (PSC-CO …

The Effect Of Feedback On A Remote Operator’S Maneuvering Control For Mass Remote Navigation Competency, Hyoseon Hwang, Ik-Hyun Youn

Journal of Marine Science and Technology–Taiwan

The rapid advancement of Maritime Autonomous Surface Ships (MASS) technology has highlighted the growing need for Remote Operators (ROs) to manage MASS effectively. ROs possess specialized competencies in areas such as situational awareness, crisis management, and system operation. Despite the introduction of competency-based training and assessment in the maritime sector through the international convention on standards of training, certification, and watchkeeping for seafarers convention, the framework's implementation remains incomplete, particularly in remote operator training for MASS. This study is purpose to identify which competencies improve rapidly with performance feedback and which improve slowly. This study conducted an experiment to quantitatively …

Evaluation Of Carbon Sequestration In Seagrass Meadows Of Kenting: A Comparative Study With Penghu And Dongsha Island, Zih-Wei Tang, Huei-Fen Chen, Jordi Mahardika Puntu, Ping-Yu Chang, Li Lo, Jian-Jhih Chen, Wen-Chen Chou, Lan-Feng Fan, Ying-Ju Chang

Journal of Marine Science and Technology–Taiwan

This study investigates the controlling factors of carbon sequestration (CS) in seagrass bed sediments across three distinct environments in Taiwan: the Kenting (KT) coastal area, the Penghu (PH) open inner bay, and the Dongsha (DS) Atoll lagoon. Actual measurements of the substrate depth beneath the sediment and ground-penetrating radar (GPR) scans of the beach reveal that the coral reef bedrock in KT slopes landward. A field survey of the seagrass area in KT was conducted, and three cross-sectional profiles were analyzed to determine their topography, yielding a median sediment thickness of 88.2cm. Based on these measurements, the sediment volume was …

Calculation Of Aquifer Transmissivity From Borehole Resistance Measurements And Pumping Test Results, Fen-Rong Yang, Chien-Wei Huang, Tien-Kuen Huang

Journal of Marine Science and Technology–Taiwan

Transmissivity is a crucial hydrogeological parameter for evaluating groundwater resources. This parameter is conventionally evaluated using pumping tests; however, these tests are costly and can be conducted at few sites. Many researchers have used ground resistance and pumping test data to estimate various hydrogeological parameters. In this study, borehole resistance survey and pumping test data collected by the Taiwan Groundwater Monitoring Network were used to establish the relationship between transmissivity and formation factor for aquifers in the Zhuoshui River alluvial fan. This relationship was then used to estimate the water output of the aforementioned aquifers in a cost-effective manner from …

A Neural Network-Based Sliding Mode Adaptive Control System For Unmanned Surface Vehicles, Sun Qiaomei, An Liang, Jiang Linglin

Journal of Marine Science and Technology–Taiwan

Over the past decades, numerous studies have explored the use of autonomous unmanned surface vehicles (USVs). Successful USV operation requires a robust tracking control system to perform a range of tasks. However, USV dynamics are uncertain, time-varying, and nonlinear. This paper presents a neural network-based sliding mode adaptive control (NNSMAC) system to enhance USV tracking performance. Trajectories were generated using spline and polynomial interpolation based on a set of N predefined waypoints. Simulation results show that the proposed method outperforms traditional sliding mode control in error reduction, enabling more effective tracking.