Oceanography Commons^™

Diatom Community Composition Shifts Driven By Coherent Cyclonic Mesoscale Eddies In The California Current System, Zuzanna Maria Abdala

OES Theses and Dissertations

The California Current System (CCS) is characterized by an equatorward flowing eastern boundary current, as well as seasonal wind-driven coastal upwelling which supplies nutrient-rich waters to the surface and drives high coastal productivity. Cyclonic mesoscale eddies form off the coast in the CCS where they trap the highly productive upwelled coastal waters, along with their resident planktonic communities, and transport them offshore into the more oligotrophic California Current waters. The interaction between waters within and outside of the eddies is limited, and so the eddies act as natural mesocosms, where the resident phytoplankton population undergo ecological succession as the eddy …

Una Evaluación De La Evolución Y El Futuro De La Vigilancia De La Pesca Ilegal En Antártida Bajo La Ccrvma, Courtney Jacobs

Independent Study Project (ISP) Collection

Este documento de investigación evalúa el tema de la pesca ilegal en el Área de la Convención de la Antártida establecida por la Comisión para la Conservación de los Recursos Vivos Marinos Antárticos (CCRVMA). El enfoque general de esta investigación es evaluar la capacidad de la Comisión para abordar la preocupación de la pesca ilegal en el Área de la Convención. Este objetivo se persigue examinando tres subpreguntas: ¿cómo ha evolucionado la pesca ilegal en el Área de la Convención a lo largo del período estudiado, qué medidas ha tomado con éxito la Comisión con respecto al monitoreo y cumplimiento …

Innovative Protection And Conservation Of Coral Reefs In Madagascar, Meghan Parker

Independent Study Project (ISP) Collection

Madagascar is home to approximately 3,450 kilometers of coral reefs, including some of the most biodiverse and valuable marine ecosystems in the Indian Ocean (Webster 2002). This online research project investigates the status of Madagascar’s coral reefs separated by region, threats that are facing the reefs and community-based solutions to protect and conserve the reefs. Conclusions of this online research suggest that most coral reefs in Madagascar are in relatively good health, although looming threats exist from overfishing, increased coastal populations, tourism, and warming waters. Community-based solutions are abundant and have proven effective, and can be implemented nation-wide, personalized to …

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

Library Impact Statements

No abstract provided.

Phytoplankton And Carbon Dynamics In The Estuarine-Coastal Waters Of The Northern Gulf Of Mexico From Field Data And Ocean Color Remote Sensing, Bingqing Liu

LSU Doctoral Dissertations

In this study, phytoplankton community and carbon dynamics were examined in the optically complex estuarine-coastal regions of the northern Gulf of Mexico (nGOM) from field and satellite ocean color observations. As part of this study, bio-optical ocean color algorithms for i) dissolved organic carbon (DOC), ii) phytoplankton pigment composition, iii) adaptive estimation of Chl a and iv) phytoplankton size fractions were developed to facilitate the study of biogeochemical cycling in the nGOM.

The phytoplankton based algorithms were applied to Sentinel 3A/B-OLCI oean color data to assess phytoplankton community dynamics to extreme river discharge conditions as well as hurricanes in the …

Changes In Atmospheric, Meteorological, And Ocean Parameters Associated With The 12 January 2020 Taal Volcanic Eruption, Feng Jing, Akshansa Chauhan, Ramesh P. Singh, Prasanjit Dash

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The Taal volcano erupted on 12 January 2020, the first time since 1977. About 35 mild earthquakes (magnitude greater than 4.0) were observed on 12 January 2020 induced from the eruption. In the present paper, we analyzed optical properties of volcanic aerosols, volcanic gas emission, ocean parameters using multi-satellite sensors, namely, MODIS (Moderate Resolution Imaging Spectroradiometer), AIRS (Atmospheric Infrared Sounder), OMI (Ozone Monitoring Instrument), TROPOMI (TROPOspheric Monitoring Instrument) and ground observations, namely, Argo, and AERONET (AErosol RObotic NETwork) data. Our detailed analysis shows pronounced changes in all the parameters, which mainly occurred in the western and south-western regions because the …

Methanethiol, Dimethyl Sulfide And Acetone Over Biologically Productive Waters In The Southwest Pacific Ocean, Sarah J. Lawson, Cliff S. Law, Mike J. Harvey, Thomas G. Bell, Carolyn F. Walker, Warren J. De Bruyn, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Atmospheric methanethiol (MeSH_a), dimethyl sulfide (DMS_a) and acetone (acetone_a) were measured over biologically productive frontal waters in the remote southwest Pacific Ocean in summertime 2012 during the Surface Ocean Aerosol Production (SOAP) voyage. MeSH_a mixing ratios varied from below the detection limit (< 10 ppt) up to 65 ppt and were 3 %–36 % of parallel DMS_a mixing ratios. MeSH_a and DMS_a were correlated over the voyage (R²=0.3, slope = 0.07) with a stronger correlation over a coccolithophore-dominated phytoplankton bloom (R²=0.5, slope 0.13). The diurnal cycle for MeSH_a shows similar behaviour to DMS_a with mixing ratios …

Investigation Of Retention Versus Export Of Planktonic Fish Eggs In The Northeastern Gulf Of Mexico, Bich Vi Viviane Nguyen

USF Tampa Graduate Theses and Dissertations

Planktonic fish eggs can be reliably identified with DNA barcoding, and their distribution and abundance can be monitored. Passive drifting fish eggs can be advected by ocean currents and as a result, can either be locally retained or exported away from the West Florida Shelf (WFS). Investigating their retention or export helps in the interpretation of egg abundance trends and in understanding their distribution in long-term surveys. The present investigation was performed in two steps using a combination of biological and physical oceanographic methods. First, fish fecundity of three species (Red Snapper, Vermilion Snapper, and Sand Perch) was assessed, first, …

Effect Of Channelized And Unchannelized Lateral Outflow On Three-Dimensional Flow Structure And Sediment Transport Mechanisms In A River Delta, Mohammad Kifayath Chowdhury

LSU Master's Theses

Spatial and temporal patterns in three-dimensional flow structure have been linked to channel morphology and processes in many environments, including river meander bends, confluences-diffluences, and bedrock canyons. However, there is not yet an understanding of how channelized and gradual, distributed lateral outflows that are often prevalent in deltaic distributary systems influence three-dimensional flow structure and sediment transport mechanisms. This thesis presents an analysis of 3D flow structure data collected from Wax Lake Delta, a naturally developing river-dominated delta in the northern Gulf of Mexico. Three hydrographic surveys were conducted using boat-mounted acoustic Doppler current profiler (ADCP) at two sites: an …

Rockhounding, Seafaring, And Other Material Tales For The End Of The World, Noemie Fortin

The Goose

In the face of accelerated environmental degradation and climate instability, the future of the Earth and of all life on earth is difficult to visualize. Therefore, the different mediums through which we consider environmental issues are just as important as the actions we take to address them. Focusing on three projects combining art, science, and activism, this article suggests a compilation of material tales. They tell stories of plastic rocks and aluminum nuggets where the protagonists are partly finely crafted objects, partly waste materials, and sometimes both at once. Artists Kelly Jazvac, Yesenia Thibeault-Picazo, and the collective Studio Swine collaborate …

Marine Carbonyl Sulfide (Ocs) And Carbon Disulfide (Cs2): A Compilation Of Measurements In Seawater And The Marine Boundary Layer, Sinikka T. Lennartz, Christa A. Marandino, Marc Von Hobe, Meinrat O. Andreae, Kazushi Aranami, Elliot Atlas, Max Berkelhammer, Heinz Bingemer, Dennis Booge, Gregory A. Cutter, Pau Cortes, Stefanie Kremser, Cliff S. Law, Andrew Marriner, Rafel Simó, Birgit Quack, Günther Uher, Huixiang Xie, Xiaobin Xu

OES Faculty Publications

Carbonyl sulfide (OCS) and carbon disulfide (CS₂) are volatile sulfur gases that are naturally formed in seawater and exchanged with the atmosphere. OCS is the most abundant sulfur gas in the atmosphere, and CS₂ is its most important precursor. They have attracted increased interest due to their direct (OCS) or indirect (CS₂ via oxidation to OCS) contribution to the stratospheric sulfate aerosol layer. Furthermore, OCS serves as a proxy to constrain terrestrial CO₂uptake by vegetation. Oceanic emissions of both gases contribute a major part to their atmospheric concentration. Here we present a database of …

Ecogeomorphic Evolution Of Muddy Coastlines: How Biota On A Range Of Scales, From Microscopic Biofilms To Landscape-Scale Vegetation Zonation Patterns, Interact With Physical Processes, Kendall Cole

LSU Doctoral Dissertations

Coastal wetland ecosystems are inherently interdisciplinary; in these spaces, the physical forces of wind and water meet to interact with stabilizing and fortifying vegetation and biota, as well as mud. The combination of these factors build and sustain wetland ecosystems and without the complex feedbacks, they would cease to exist. In this dissertation, I present three studies that focus on ecogeomorphic interactions within coastal wetlands on a range of scales, from microscopic to the entire landscape and highlight the importance of these interactions when predicting future coastal change. The first study examined how biofilms, matrixes of photosynthetic diatoms and their …

Simulating Wave Dynamics In The Northern Gulf Of Mexico And Barataria Pass, Azadeh Razavi Arab

LSU Master's Theses

The coastal wetlands of Louisiana constitute ~40% of the wetlands in the United States. However, it suffers from 80% of the wetland losses in the whole country. In shallow coastal and estuarine environments, bed shear stresses related to wind waves contributes substantially to the edge erosion in the northern Gulf of Mexico (NGoM). Therefore, wave simulations in shallow estuarine areas are of great importance.

There are several challenges in simulating waves nearshore, especially over the shallow and nearly horizontal sea beds typical of the NGoM continental shelf and adjacent complex geometry estuaries: determination of the appropriate wind forcing dataset to …

Role Of Coastal Environmental Conditions During Austral Winter On Plankton Community Dynamics And The Occurrence Of Pseudo-Nitzschia Spp. And Domoic Acid In Inhambane Province, Mozambique, Holly Kelchner

LSU Master's Theses

Harmful algal blooms (HABs) are increasing globally in frequency, persistence, and geographic extent. HABs pose a threat to economic stability, and ecosystem and human health. To date no incidences of marine toxins produced by phytoplankton have been recorded in Mozambique, which may be due to the absence of a monitoring program and general awareness of the potential threat. This study is the first documentation of the occurrence of a neurotoxin, domoic acid (DA), produced by the diatom genus Pseudo-nitzschia spp. along the east coast of Africa. The coast of Inhambane Province is a biodiversity hotspot where year-round Rhincodon typus (whale …

Late Cretaceous Stratigraphy And Paleoceanographic Evolution In The Great Australian Bight Basin Based On Results From Iodp Site U1512, K. G. Macleod, Lloyd T. White, Carmine C. Wainman, Mathieu Martinez, Matthew M. Jones, Sietske J. Batenburg, Laurent Riquier, Shannon J. Haynes, David K. Watkins, K. A. Bogus, H.-J. Brumsack, R. Do Monte Guerra, Kirsty M. Edgar, Trine Edvardsen, Dennis Harry, Takashi Hasegawa, R. W. Hobbs, Brian T. Huber, T. Jiang, J. Kuroda, E. Y. Lee, Yong-Xiang Li, Alessandro Maritatai, Lauren K. O'Connor, Maria Rose Petrizzo, Tracy M. Quan, C. Richter, Maria Luisa Garcia Tejada, G. Tagliaro, Erik Wolfgring, Zhaokai Xu

Department of Earth and Atmospheric Sciences: Faculty Publications

The Upper Cretaceous sedimentary sequence at International Ocean Discovery Program Site U1512 in the Ceduna Sub-basin of the Great Australian Bight represents a continuous, N 690 m thick interval of black silty clay and claystone spanning the lower Turonian through Lower Campanian (~10 million years). Sediments were deposited in an elongate, ~E-W oriented, ~2500 km long rift system that developed between Australia and Antarctica with an open-ocean connection to the west and a continental bridge to the east. Site U1512 cores provide a unique, continuous record of Late Cretaceous deposition in the Ceduna Sub-basin on the hanging wall of the …

Assessment Of Soil Protein And Refractory Soil Organic Matter Across Two Chronosequences Of Newly Developing Marshes In Coastal Louisiana, Usa, Stuart Alexander Mcclellan

LSU Doctoral Dissertations

The impacts of sea-level rise and hydrologic manipulation are threatening the stability of coastal marshes throughout the world, thereby increasing the potential for re-mineralization of soil organic matter (SOM) in these systems. Such threats have prompted marsh restoration efforts, particularly in coastal Louisiana, yet it is unclear how the slowly decomposing (refractory) and quickly decomposing (labile) fractions of SOM may be differentially affected by different approaches to marsh restoration. Additionally, otherwise labile compounds may accumulate in the soil via a range of protective mechanisms, including rapid burial and association with organic compounds that are thought to enhance soil aggregation, such …

Organic Sulfur: A Spatially Variable And Understudied Component Of Marine Organic Matter, Krista Longnecker, Lisa Oswald, Melissa C. Kido Soule, Gregory A. Cutter, Elizabeth B. Kujawinski

OES Faculty Publications

Sulfur (S) is a major heteroatom in organic matter. This project evaluated spatial variability in the concentration and molecular-level composition of organic sulfur along gradients of depth and latitude. We measured the concentration of total organic sulfur (TOS) directly from whole seawater. Our data reveal high variability in organic sulfur, relative to established variability in total organic carbon or nitrogen. The deep ocean contained significant amounts of organic sulfur, and the concentration of TOS in North Atlantic Deep Water (NADW) decreased with increasing age while total organic carbon remained stable. Analysis of dissolved organic matter extracts by ultrahigh resolution mass …

A Pre-Industrial Sea-Level Rise Hotspot Along The Atlantic Coast Of North America, W. R. Gehrels, Sönke Dangendorf, N. L. M. Barlow, M. H. Saher, A. J. Long, P. L. Woodworth, C. G. Piecuch, K. Berk

CCPO Publications

The Atlantic coast of North America north of Cape Hatteras has been proposed as a “hotspot” of late 20th century sea‐level rise. Here we test, using salt‐marsh proxy sea‐level records, if this coast experienced enhanced sea‐level rise over earlier multidecadal‐centennial periods. While we find in agreement with previous studies that 20th century rates of sea‐level change were higher compared to rates during preceding centuries, rates of 18th century sea‐level rise were only slightly lower, suggesting that the “hotspot” is a reoccurring feature for at least three centuries. Proxy sea‐level records from North America (Iceland) are negatively (positively) correlated with centennial …

Microplastics In Aquatic Organisms: Improving Understanding And Identifying Research Directions For The Next Decade, Elise F. Granek, Susanne Brander, E. B. Holland

Environmental Science and Management Faculty Publications and Presentations

The study of environmental microplastics has increased over the past decade, with hundreds of new studies and resultant papers on the presence, fate, and sources of microplastics in marine and freshwater systems (Fig. 1). Despite the explosion of interest in the topic and in comparison to the research on the presence of microplastics in marine or fresh waters, there have been notably fewer studies on the extent to which these debris items are ingested by aquatic organisms and far fewer on the potential consequences, or response to their presence in organismal guts, tissues, and food webs. Even less research has …

Reproductive Biology And Trophic Niche Of Hardhead Catfish In The Northern Gulf Of Mexico, Lucas G. Pensinger

LSU Master's Theses

Generally, marine fishes have very high fecundity with each female producing many small eggs which hatch into small larvae. However, Ariopsis felis, a species of marine catfish common to coastal Louisiana, has low fecundity and produces the largest eggs of the teleost fishes. Despite wide range and generally high abundance, we know very little of A. felis biology and population. The few existing studies of A. felis are older and often have questionable or unclear methodology.

I examined four aspects of A. felis reproductive biology: 1) reproductive timing,

2) fecundity, 3) length at first maturity, and 4) mouth brooding. …

Air/Sea Transfer Of Highly Soluble Gases Over Coastal Waters, J. G. Porter, Warren J. De Bruyn, S. D. Miller, E. S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The deposition of soluble trace gases to the sea surface is not well studied due to a lack of flux measurements over the ocean. Here we report simultaneous air/sea eddy covariance flux measurements of water vapor, sulfur dioxide (SO₂), and momentum from a coastal North Atlantic pier. Gas transfer velocities were on average about 20% lower for SO₂ than for H₂O. This difference is attributed to the difference in molecular diffusivity between the two molecules (D _{SO 2}/D _{H 2O} = 0.5), in reasonable agreement with bulk parameterizations in air/sea gas …

Correlation Between Ocean Acidification And Zooplankton In The South Pacific Gyre, Samuel Noonan, Rachel Scudder

DU Undergraduate Research Journal Archive

The South Pacific Gyre is a naturally occurring carbon sink, meaning that it absorbs atmospheric carbon dioxide by dissolving it into the moving surface water. The dissolution of CO2 level will dictate the water’s acidic levels a larger the concentration of dissolved CO2 is known to increase the salt water’s acidity. A great amount of the ocean’s biomass is composed of calcifying organisms, which produce tests or shells made from calcium carbonate CaCO3.The goal of our project is to determine if there is a correlation between the water acidity across various locations, as we sailed through the South Pacific gyre …

Fiddler Crabs And Selfish Herds: High School Cliques Or More Diverse?, Shelby Warrelmann

Bridges: A Journal of Student Research

Marsh fiddler crabs (Uca pugnax) have diverse foraging habits which are dependent on the personality of each crab. The formation of droves or preference to scavenge alone may correspond to factors such as: Location within a herd, herd size, size of males, and feeding rate. Previous research suggests that 1) a central location in a herd corresponds to an increase in feeding rate 2) herd size doesn't affect feeding rates and 3) location within a herd often is related to an individual's size. A multi-year observational study was conducted to determine the validity of these claims and found that while …

Dissolved Inorganic Nitrogen Dynamics In Swash Zone Sands Of Long Bay, Sc, Alexis F. Echols

Bridges: A Journal of Student Research

A key component affecting the biogeochemistry of the sedimentary environment is pore water between grains of sediments. Sedimentary microorganisms are constantly modifying chemical compounds as part of their life functions which are then exchanged between the sediment column and the overlying water column. Dissolved inorganic nitrogen, a major element for life, takes on several forms including nitrate, nitrite, and ammonium which vary in concentration throughout the sediment and with respect to each other. The relative concentrations of these nitrogen species have been previously briefly explored in sandy columns, where redox gradients that control their relative concentrations can be fairly deep …

Size And Density Of Upside-Down Jellyfish, Cassiopea Sp., And Their Impact On Benthic Fluxes In A Caribbean Lagoon, Chester B. Zarnoch, Noshin Hossain, Erika Fusco, Mary Alldred, Timothy J. Hoellein, Sophia Perdikaris

School of Global Integrative Studies: Faculty Publications

Anthropogenic disturbances may be increasing jellyfish populations globally. Epibenthic jellyfish are ideal organisms for studying this phenomenon due to their sessile lifestyle, broad geographic distribution, and prevalence in near-shore coastal environments. There are few studies, however, that have documented epibenthic jellyfish abundance and measured their impact on ecological processes in tropical ecosystems. In this study, the density and size of the upside-down jellyfish (Cassiopea spp.) were measured in Codrington Lagoon, Barbuda. A sediment core incubation study, with and without Cassiopea, also was performed to determine their impact on benthic oxygen and nutrient fluxes. Densities of Cassiopea were 24–168 …

Dropsonde Observations Of The Ageostrophy Within The Pre-Cold-Frontal Low-Level Jet Associated With Atmospheric Rivers, Rueben Demirdgian, Joel R. Norris, Andrew Martin, F. Martin Ralph

Geography Faculty Publications and Presentations

The pre-cold-frontal low-level jet (LLJ) is an important contributor for water vapor transport within atmospheric rivers, though its dynamics are not completely understood. The present study investigates the LLJ using dropsonde observations from 24 cross-atmospheric river transects taken during the CalWater-2014, 2015 and the AR-Recon 2016, 2018 field campaigns. It is found that the LLJ, located at ;1-km elevation ahead of the cold front, has an average maximum wind speed of 30ms21 and is strongly supergeostrophic with an average ageostrophic component of 6ms21. The alongfront ageostrophy occurs within the atmospheric layer (750–1250 m) known to strongly control orographic precipitation associated …

Projecting Regions Of North Atlantic Right Whale, Eubalaena Glacialis, Habitat Suitability In The Gulf Of Maine In 2050, Camille Ross

Honors Theses

North Atlantic right whales (Eubalaena glacialis) are endangered. Understanding the role environmental conditions play in habitat suitability is key to determining the regions in need of protection for conservation of the species, particularly as climate change shifts suitable habitat. This thesis uses three species distribution modeling algorithms, together with historical data on whale abundance(1993 to 2009) and environmental covariates to build monthly ensemble models of past E. glacialis habitat suitability in the Gulf of Maine. Then, the models are projected onto the year 2050 for a range of climate scenarios. Specifically, the distribution of the species was modeled …

Abiotic Formation Of Dissolved Organic Sulfur In Anoxic Sediments Of Santa Barbara Basin, Hussain A. Abdulla, David J. Burdige, Tomoko Komada

OES Faculty Publications

Sulfurization has been found to enhance organic matter preservation and petroleum formation in marine sediments. However, we do not yet have a comprehensive understanding of sulfurization mechanisms. In this study, we investigated several possible mechanisms of dissolved organic sulfur (DOS) formation in the top 4.5 m of anoxic sediments of Santa Barbara Basin (SBB), California Borderland. Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS), we identified chemical formulas of potential dissolved organic matter (DOM) precursors to these DOS compounds. We also examined how the formulas of abiotically formed DOS changed as a function of depth across a major redox …

An Oceanographic Perspective On Early Human Migrations To The Americas, Thomas C. Royer, Bruce Finney

OES Faculty Publications

Early migrants to the Americas were likely seaworthy. Many archaeologists now agree that the first humans who traveled to the Americas more than 15,000 years before present (yr BP) used a coastal North Pacific route. Their initial migration was from northeastern Asia to Beringia where they settled for thousands to more than ten thousand years. Oceanographic conditions during the Last Glacial Maximum (18,000-24,000 yr BP) would have enhanced their boat journeys along the route from Beringia to the Pacific Northwest because the influx of freshwater that drives the opposing Alaska Coastal Current was small, global sea level was at least …

Towards Sustained Monitoring Of Subsidence At The Coast Using Insar And Gps: An Application In Hampton Roads, Virginia, Brett Buzzanga, David P.S. Bekaert, Ben D. Hamlington, Simran S. Sangha

OES Faculty Publications

Hampton Roads is among the regions along the U.S. Atlantic Coast experiencing high rates of relative sea level rise. Partly to mitigate subsidence from aquifer compaction, Hampton Roads is injecting treated wastewater into the underlying aquifer. However, the GPS (Global Positioning System) station spacing (∼30 km) is too coarse to capture the spatial variability of subsidence and potential uplift from the injection. We present a cost‐effective workflow for generating an InSAR (interferometric synthetic aperture radar) and GPS combined displacement product. We leverage a live, open‐access archive of InSAR products generated from Sentinel‐1 data. We find an overall subsidence rate of …