Oceanography Commons^™

Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance

Faculty Publications

This study presents Eulerian data from Winyah Bay, SC, USA collected during the passage of a tidal plume. The data captured the evolution and structure of the plume and include high-resolution velocity and temperature time series, supplemented by temperature – salinity profiles from a MicroCTD profiler. The observations identified a pre-existing plume extending to 4 m, with a water density of 1023.6 kg m⁻³, laying above denser ambient waters. Upon arrival, the newly discharged tidal plume introduced a fresher layer (1020.7 kg m⁻³) extending to 2.6 m, gradually thinning due to radial spreading. The plume's frontal …

My Octopus Teacher (2020) Directed By Pippa Ehrlich And James Reed, Peter Shea

Picture Books

My Octopus Teacher combines a carefully structured love story with astonishing information about undersea life, documenting a year of encounters between a photographer and an octopus. It is important as a non-standard love story and as a reflection on the possibility of deep connection with non-human creatures.

Unveiling Hidden Mercury And Methylmercury Sources: The Role Of Submarine Groundwater Discharge In Coastal Lagoons, Céline Lavergne, Júlia Rodriguez-Puig, Clara Ruiz-González, Maria Montero-Curiel, Gemma Casas, Daniel Romano-Gude, Irene Alorda-Montiel, Júlia Dordal-Soriano, Aaron Alorda-Kleinglass, Marc Diego-Feliu, Javier Gilabert, Alex Campillo-De La Maza, Cristina Romera-Castillo, Natalia Torres-Rodriguez, Lars-Eric Heimbürger-Boavida, Jordi Garcia-Orellana, Valenti Rodellas, Andrea G. Bravo

OES Faculty Publications

Mercury loads from Submarine Groundwater Discharge (SGD) may represent an overlooked source of methylmercury (MeHg) to the ocean, affecting human and ecosystem health. The SGD process involves the flow of fresh, saline, or mixed groundwater from coastal aquifers into the oceans classified in different components. Existing studies rarely report the fluxes supplied by the different SGD components; therefore, the relevance of SGD as a source of mercury remains unclear. We aimed to quantify SGD-driven mercury/methylmercury fluxes to the coast, focusing on the largest coastal lagoon in the western Mediterranean. We measured total dissolved mercury and MeHg in surficial and porewaters …

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 …

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 …

Predictive Maintenance In Naval Vessel Propulsion Systems For Enhanced Marine Operations Using A Bigmm-Hmm Framework With Divergence-Based Clustering, Farshid Javadnejad, Hyoshin John Park, Samuel Kovacic, Andres Sousa-Poza

Engineering Management & Systems Engineering Faculty Publications

This study introduces a BiGMM-HMM Integration Framework designed to improve predictive maintenance strategies for naval vessel propulsion systems, addressing the need for efficient and reliable operation in marine engineering applications. The framework effectively manages multimodal sensor data by leveraging a unique combination of Gaussian Mixture Models (GMMs) and Hidden Markov Models (HMMs) in a bidirectional architecture. It analyses the dynamic interactions between sensors and subsystems. Two preprocessing methods are evaluated: Method 1 focuses on subsystem interactions, employing divergence-based root cause analysis to identify key sensor variables by clustering of sensors and subsystems. In contrast, Method 2 processes the entire dataset …

Moderate Heating Renders 7.8-Million-Year-Old Sedimentary Organic Matter Bioavailable, Shuchai Gan, Verena B. Heuer, Frauke Schmidt, Lars Wormer, Faming Wang, Rishi R. Adhikari, Patrick Hatcher, Ann Pearson, Kai-Uwe Hinrichs

Chemistry & Biochemistry Faculty Publications

Marine sediments are a large reservoir of recalcitrant organic matter and host microbes at subsurface depths exceeding 2.4 kilometers and temperatures up to 120°C, yet the mechanisms supplying bioavailable substrates remain unclear. Here, we investigated 7.8-million-year-old sediment from IODP Site C0012 off the Nankai Trough, Japan, through incubations at 20°, 35°, 55°, and 85°C to simulate burial temperatures. Using 3D fluorescence spectroscopy and ultrahigh-resolution mass spectrometry, we tracked changes in dissolved organic matter (DOM). At 35°C, humic-like DOM was released alongside metal ions, exhibiting low bioavailability. At 55°C, abiotic decomposition of humic compounds generated smaller, more bioavailable DOM, promoting fermentation. …

Bioaccumulation Of Legacy And Novel Pfas In The Environment, Hesham Taher, Rainer Lohmann

Graduate School of Oceanography Faculty Publications

The bioaccumulation of per- and polyfluoroalkyl substances (PFAS), both legacy and novel, in the environment presents significant ecological and health risks. PFAS are a diverse group of synthetic chemicals known for their persistence and bioaccumulation, which can cause widespread environmental contamination and health risks. Strong carbon-fluorine bonds give these compounds unparalleled stability, preventing them from degrading and enabling them to endure in a range of environmental matrices, including water, soil, and biota. Legacy PFAS, including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), have been extensively studied and regulated, resulting in lower concentrations in some environmental media. However, novel PFAS, …

A Statistical Fetch Model For Water Wave Glint Correction Using Worldview-3 Imagery, Amanda Jade Quintanilla

Theses and Dissertations

Sun glint in satellite imagery of the water surface contaminates the upwelling signal received by a detector. Many models exist that attempt to correct for this wave facet effect and phenomena. In this work a model for sun glint correction is created using the comparison of image transects between two nearly simultaneously collected images of the same area, although with differing sensor geometry. One image utilized in this research is almost entirely glint free while the other is contaminated by water wave facet glint. Although many models for removing sun glint exist based on various techniques, none are completely accurate, …

Ecological Assessment Of Drainage Water Input On The Water Quality Of A Coastal Estuary, Mediterranean Coast Of Egypt, Fatma A. Zaghloul, Hoda A. E. Hemaida, Hayat M. Faragallah, Ahmed A. Radwan

Blue Economy

El Mex Bay, located west of Alexandria City, is identified as a hot spot of pollution along the Mediterranean coast of Egypt. It is a large, shallow, and turbid water body of socioeconomic importance. However, El Mex Bay receives a large amount of untreated industrial wastewater, as well as agricultural runoff from different land-based sources.

A comprehensive environmental study was carried out seasonally during 2020-2021. To evaluate the effect of this discharged wastewater on the water quality of El Mex Bay.

The physicochemical parameters were measured at both the surface and near-bottom water at nine stations.

Principal component analysis indicated …

Intercalibration: A Cornerstone Of The Success Of The Geotraces Program, Ana Aguilar-Islas, Hélène Planquette, Maeve C. Lohan, Walter Geibert, Gregory Cutter

OES Faculty Publications

The international GEOTRACES program was developed to enhance knowledge about the distribution of trace elements and their isotopes (TEIs) in the ocean and to reduce the uncertainty about their sources, sinks, and internal cycling. Recognizing the importance of intercalibration from the outset, GEOTRACES implemented intercalibration efforts early in the program, and consensus materials were generated that included the full range of TEIs dissolved in seawater, in suspended particles, and from aerosols. The GEOTRACES section cruises include “crossover station(s)” that are occupied by two or more sections and whereby all aspects of sample collection, preservation, and processing can be compared and …

Marine Emissions Of Methanethiol Increase Aerosol Cooling In The Southern Ocean, Charel Wohl, Julián Villamayor, Martí Galí, Anoop S. Mahajan, Rafael P. Fernández, Carlos A. Cuevas, Adriana Bossolasco, Qinyi Li, Anthony J. Kettle, Tara Williams, Roland Sarda-Esteve, Valérie Gros, Rafel Simó, Alfonso Saiz-Lopez

OES Faculty Publications

Ocean-emitted dimethyl sulfide (DMS) is a major source of climate-cooling aerosols. However, most of the marine biogenic sulfur cycling is not routed to DMS but to methanethiol (MeSH), another volatile whose reactivity has hitherto hampered measurements. Therefore, the global emissions and climate impact of MeSH remain unexplored. We compiled a database of seawater MeSH concentrations, identified their statistical predictors, and produced monthly fields of global marine MeSH emissions adding to DMS emissions. Implemented into a global chemistry-climate model, MeSH emissions increase the sulfate aerosol burden by 30 to 70% over the Southern Ocean and enhance the aerosol cooling effect while …

On The Links Between Sea Level And Temperature Variations In The Chesapeake Bay And The Atlantic Meridional Overturning Circulation (Amoc), Tal Ezer, Teresa Updyke

CCPO Publications

Recent studies found that on long time scales there are often unexplained opposite trends in sea level variability between the upper and lower Chesapeake Bay (CB). Therefore, daily sea level and temperature records were analyzed in two locations, Norfolk in the southern CB and Baltimore in the northern CB; surface currents from Coastal Ocean Dynamics Application Radar (CODAR) near the mouth of CB were also analyzed to examine connections between the CB and the Atlantic Ocean. The observations in the bay were compared with daily Atlantic Meridional Overturning Circulation (AMOC) observations during 2005–2021. Empirical Mode Decomposition (EMD) analysis was used …

Wavelet Compression As An Observational Operator In Data Assimilation Systems For Sea Surface Temperature, Bradley J. Sciacca

LSU New Orleans Theses and Dissertations

The ocean remains severely under-observed, in part due to its sheer size. Containing nearly billion of water with most of the subsurface being invisible because water is extremely difficult to penetrate using electromagnetic radiation, as is typically used by satellite measuring instruments. For this reason, most observations of the ocean have very low spatial-temporal coverage to get a broad capture of the ocean’s features. However, recent “dense but patchy” data have increased the availability of high-resolution – low spatial coverage observations. These novel data sets have motivated research into multi-scale data assimilation methods. Here, we demonstrate a new assimilation approach …

Spatial And Temporal Variations Of Microplastics Within Humboldt Bay, California, Isabelle M. Marcus, Tamara B. Barriquand, Rebecca M. Thompson, Bennett C. Hosselkus, Cole T. Hutson, Michael Jacobs, Connor Mcneil, Leah Newton, Stephanie M. Olivarez, Jeffrey Abell

CSU Journal of Sustainability and Climate Change

This study aimed to quantify microplastic (MP) concentration and analyze the spatial and temporal variabilities of the concentrations during the tidal cycle in Humboldt Bay, California. To get an approximation of MP concentration, both water and sediment samples were taken at five different stations, twice during one tidal cycle. Sampling was conducted during two different cruises, on the 19th and 21st of September 2020. The samples were processed in the lab using a density separation procedure and filtration. MP concentrations in the different samples were determined using an average optical microscopy count. Comparison of the water column MP concentrations during …

Arctic Ocean And Subarctic Seas Dynamics In A Changing Climate, Sarah B. Hall

Theses and Dissertations

Salinity is the primary determinant of the Arctic Ocean’s vertical density stratification in the upper ocean, which has major implications on the ocean’s physical dynamics alongside a period of rapidly declining sea ice. In recent decades, the Arctic’s freshwater content (FWC) has increased as a result of the accumulation of freshwater source inputs. Additional freshwater exported to the North Atlantic may hinder overturning processes that are vital to the regulation of global climate. This dissertation employs in situ measurements, satellite observations, and ocean model simulations to better understand salinity and freshwater changes in the Arctic Ocean during this changing climate. …

Understanding Biogeochemical And Physical Controls On Methane Air-Sea Exchange Fluxes In The Pacific Ocean, Sarah Raney

Master's Theses

Methane and trace element samples were collected on GEOTRACES GP15 Pacific Meridional Transect (PMT) cruise conducted between the Aleutian Islands (57 °N) and Tahiti (20 °S) from September to November 2018. Uncertainty in methane air-sea exchange fluxes was determined using a propagation of errors approach. Fluxes ranged from -0.88 to 4.9 µmol CH₄ m^-2 d^-1. Average CH₄ flux along the Alaskan margin was 2.2 ± 2.9 µmol CH₄ m^-2 d^-1. Methane fluxes decreased moving southward and increased to their open ocean maximum around 20 °N before declining in equatorial waters. Near …

Power In Numbers: An Abundance Of Small Corals Responsible For Storing Over Half Of The Carbon Stored By All Alaskan Primnoa Pacifica Deep-Sea Corals, Sylvie Alexander

Scripps Senior Theses

Gorgonian deep-sea corals (DSCs) are biologically linked to ocean carbon cycling converting ocean carbon to gorgonin and calcite in their skeletons. As such, gorgonian DSCs likely accumulate and store carbon in their skeleton throughout their lifespans, acting as carbon sinks on historic timescales. Yet, DSC carbon storage hasn’t been investigated to date. This study evaluates gorgonian DSC carbon storage capacity through an evaluation of the carbon stored by Alaskan Primnoa pacifica corals. The development of a model relating coral height to biomass in specimens with this data available was used to determine biomass values in a suite of Alaskan P. …

The Aquatic Particle Number Quandry, Alexander B. Bochdansky, Huanqing Huang, Maureen H. Conte

OES Faculty Publications

Optical surveys of aquatic particles and their particle size spectra have become important tools in studies of light propagation in water, classification of water masses, and the dynamics of trophic interactions affecting particle aggregation and flux. Here, we demonstrate that typical settings used in image analysis vastly underestimate particle numbers due to the particle – gel continuum. Applying a wide range of threshold values to change the sensitivity of our detection system, we show that macrogels cannot be separated from more dense particles, and that a true particle number per volume cannot be ascertained; only relative numbers in relation to …

High-Tide Floods And Storm Surges During Atmospheric Rivers On The Us West Coast, Christopher G. Piecuch, Sloan Coats, Sönke Dangendorf, Felix W. Landerer, J. T. Reager, Philip R. Thompson, Thomas Wahl

CCPO Publications

Amospheric rivers (ARs) effect inland hydrological impacts related to extreme precipitation. However, little is known about the possible coastal hazards associated with these storms. Here we elucidate high-tide floods (HTFs) and storm surges during ARs through a statistical analysis of data from the US West Coast during 1980-2016. HTFs and landfalling ARs co-occur more often than expected from random chance. Between 10%-63% of HTFs coincide with landfalling ARs, depending on location. However, only 2%-15% of ARs coincide with HTFs, suggesting that ARs typically must co-occur with anomalously high tides or mean sea levels to cause HTFs. Storm surges during ARs …

The Influence Of Bottom Type And Water Column Stratification On Reef Fish Community Structure At Gray’S Reef National Marine Sanctuary, Bridget Campbell

Honors Theses

Understanding the physical and oceanographic differences across reef habitats can help researchers assess how those differences influence fish distribution and community structure, which leads to a better understanding of what a healthy reef system looks like. The traditional methods used to assess fish communities on temperate reefs are limited and often focus solely on either the reef structure or water column conditions alone. An assessment of both data sets yields a more complete understanding of the ecosystem as a whole. In this study, Gray’s Reef National Marine Sanctuary (GRNMS) was surveyed both inside and outside a Marine Protected Area (MPA) …

Examining Arctic Melt Pond Dynamics Via High Resolution Satellite Imagery, Austin Abbott, Victoria Hill

College of Sciences Posters

The Arctic Ocean is a rapidly changing environment, and a key observational system for monitoring climate change. The Arctic is going under a rapid transition from thicker, multi-year ice, to thinner first-year ice, that may have many potential consequences. As first year Arctic sea ice begins to retreat in the spring and early summer, melting snow and ice form ponds on the surface- “melt ponds”. These melt ponds increase light transmission to the water column, resulting in warming and increased primary production under the ice. Recent advances in high resolution satellite imagery now allow us to monitor the development and …

Larry Philip Atkinson 1941-2020, Gregory Cutter, Louis Codispoti

OES Faculty Publications

No abstract provided.

Taxonomic And Nutrient Controls On Phytoplankton Iron Quotas In The Ocean, Benjamin S. Twining, Olga Antipova, P. Dreux Chappell, Natalie R. Cohen, Jeremy E. Jacquot, Elizabeth L. Mann, Adrian Marchetti, Daniel C. Ohnemus, Sara Rauschenberg, Alessandro Tagliabue

OES Faculty Publications

Phytoplankton iron contents (i.e., quotas) directly link biogeochemical cycles of iron and carbon and drive patterns of nutrient limitation, recycling, and export. Ocean biogeochemical models typically assume that iron quotas are either static or controlled by dissolved iron availability. We measured iron quotas in phytoplankton communities across nutrient gradients in the Pacific Ocean and found that quotas diverged significantly in taxon‐specific ways from laboratory‐derived predictions. Iron quotas varied 40‐fold across nutrient gradients, and nitrogen‐limitation allowed diatoms to accumulate fivefold more iron than co‐occurring flagellates even under low iron availability. Modeling indicates such “luxury” uptake is common in large regions of …

Global Ocean Change Ocg 511, Joanna Burkhardt

Library Impact Statements

No abstract provided.

Marine Geobiology Ocg 502, Joanna Burkhardt

Library Impact Statements

No abstract provided.

Law School News: Dennis W. Nixon: Doctor Of Laws, Honoris Causa 05-09-2020, Roger Williams University School Of Law

Life of the Law School (1993- )

No abstract provided.

The Effect Of Radium Partitioning On Hydrothermal Fluid Flow Determination Across Guaymas Basin, Charlotte R. Kollman

Electronic Theses and Dissertations

Analysis of the distribution of radium through sedimentary porewater profiles is a promising method for constraining diffuse discharge/recharge flow rates in hydrothermal settings; these parameters are critical for evaluating hydrothermal circulation and its chemical and biological implications. The short-lived 224Ra (T1/2 = 3.54 days) is an effective tracer due to its behavior in marine environments and changes in activity due to ingrowth/decay. However, the distribution of radium may be influenced by its varying solid:aqueous partitioning coefficients (Kd) and is critical to understand for any study utilizing radium as a tracer. This project explores Kd across the hydrothermally active Guaymas Basin …

Chemical Crises In A Changing Ocean Ocg 104g, Joanna Burkhardt

Library Impact Statements

No abstract provided.

Nitrogen Assimilation In Picocyanobacteria Inhabiting The Oxygen-Deficient Waters Of The Eastern Tropical North And South Pacific, Montserrat Aldunate, Carlos Henriquez-Castillo, Qixing Ji, Jessica Lueders-Dumont, Margaret R. Mulholland, Bess B. Ward, Peter Von Dassow, Osvaldo Ulloa

OES Faculty Publications

Prochlorococcus and Synechococcus are the most abundant free-living photosynthetic microorganisms in the ocean. Uncultivated lineages of these picocyanobacteria also thrive in the dimly illuminated upper part of oxygen-deficient zones (ODZs), where an important portion of ocean nitrogen (N) loss takes place via denitrification and anaerobic ammonium oxidation. Recent metagenomic studies revealed that ODZ Prochlorococcus have the genetic potential for using different N forms, including nitrate and nitrite, uncommon N sources for Prochlorococcus, but common for Synechococcus. To determine which N sources ODZ picocyanobacteria are actually using in nature, the cellular 15N natural abundance (δ15N) and assimilation rates of …