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2018

Oceanography

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Articles 1 - 30 of 136

Full-Text Articles in Physical Sciences and Mathematics

Leveraging Student Experience With Water For Active Learning In A Large Introductory Oceanography Classroom, Rebecca Freeman Dec 2018

Leveraging Student Experience With Water For Active Learning In A Large Introductory Oceanography Classroom, Rebecca Freeman

Earth and Environmental Sciences Faculty Publications

No abstract provided.

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Summertime Connecticut River Water Pathways And Wind Impacts, Yan Jia, Michael M. Whitney Dec 2018

Summertime Connecticut River Water Pathways And Wind Impacts, Yan Jia, Michael M. Whitney

Department of Marine Sciences

Long Island Sound is a large macrotidal estuary. Connecticut River as the primary freshwater source enters near the sound’s mouth. The summertime pathways of river water under low discharge and mild wind conditions are studied through both numerical simulations with a passive dye pulse and field surface drifter observations. Within the 19-day modeling analysis period, a third of the river dye pulse moves up-estuary with the near-bottom dense inflow into central and western sound with a spring-neap tidal modulation; another third leaves the sound with the near-surface outflow towards the continental shelf through Block Island Sound. The latter pathway is …

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Multispectral Classification Of Gulf Of Maine Surface Waters: Seasonal And Interannual Variability, Brianna M. King Dec 2018

Multispectral Classification Of Gulf Of Maine Surface Waters: Seasonal And Interannual Variability, Brianna M. King

Electronic Theses and Dissertations

Bio-optically, surface waters of the northeastern US continental shelf are strongly heterogeneous, exhibiting highly variable distributions in both time and space of suspended sediment, colored dissolved organic matter (CDOM), and phytoplankton concentration and community structure. These render the standard global NASA satellite chlorophyll algorithm suspect. However, spectral signatures of the water are well quantified by the actual satellite-based multispectral reflectance (Rrs) measurements. Here, we use 6 bands of Rrs measurements from 19 years (1998-2016) of monthly composite SeaWiFS and MODIS data to identify the spectral signatures of dominant water types present over the northeast shelf. A merged multivariate clustering approach …

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Predicted Deepwater Bathymetry From Satellite Altimetry: Non-Fourier Transform Alternatives, Maxsimo Salazar Dec 2018

Predicted Deepwater Bathymetry From Satellite Altimetry: Non-Fourier Transform Alternatives, Maxsimo Salazar

Dissertations

Robert Parker (1972) demonstrated the effectiveness of Fourier Transforms (FT) to compute gravitational potential anomalies caused by uneven, non-uniform layers of material. This important calculation relates the gravitational potential anomaly to sea-floor topography. As outlined by Sandwell and Smith (1997), a six-step procedure, utilizing the FT, then demonstrated how satellite altimetry measurements of marine geoid height are inverted into seafloor topography. However, FTs are not local in space and produce Gibb’s phenomenon around discontinuities. Seafloor features exhibit spatial locality and features such as seamounts and ridges often have sharp inclines. Initial tests compared the windowed-FT to wavelets in reconstruction of …

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Trash Talk: The Effects Of Plastic Pollution On Seabirds In Narragansett Bay, Erin A. O'Neill Dec 2018

Trash Talk: The Effects Of Plastic Pollution On Seabirds In Narragansett Bay, Erin A. O'Neill

Pell Scholars and Senior Theses

Plastic pollution in the ocean is a global concern with more than 8 million tons of plastic dumped into our oceans every year. This policy paper assesses plastic pollution in Narragansett Bay and the negative implications it holds on local seabird populations. Also, essential background information on plastic production and throwaway culture is provided. Moreover, the biological significance of seabirds is described, highlighting the vital role such populations play in local ecosystems such as Narragansett Bay. This paper contributes research to the global issue of plastic pollution by observing declining native wildlife life populations, such as seabirds, on a local …

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Sediment Transport Model Including Short-Lived Radioisotopes: Model Description And Idealized Test Cases, Justin J. Birchler,, Courtney K. Harris, Christopher R Sherwood, Tara A. Kniskern Dec 2018

Sediment Transport Model Including Short-Lived Radioisotopes: Model Description And Idealized Test Cases, Justin J. Birchler,, Courtney K. Harris, Christopher R Sherwood, Tara A. Kniskern

VIMS Articles

Geochronologies derived from sediment cores in coastal locations are often used to infer event bed characteristics such as deposit thicknesses and accumulation rates. Such studies commonly use naturally occurring, short-lived radioisotopes, such as Beryllium-7 (Be-7) and Thorium-234 (Th-234), to study depositional and post-depositional processes. These radioisotope activities, however, are not generally represented in sediment transport models that characterize coastal flood and storm deposition with grain size patterns and deposit thicknesses. We modified the Community Sediment Transport Modeling System (CSTMS) to account for reactive tracers and used this capability to represent the behavior of these short-lived radioisotopes on the sediment bed. …

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Along-Shelf Connectivity And Circumpolar Gene Flow In Antarctic Silverfish (Pleuragramma Antarctica), Jilda Alicia Caccavo, Chiara Papetti, Maj Wetjen, Rainer Knust, Julian R. Ashford, Lorenzo Zane Dec 2018

Along-Shelf Connectivity And Circumpolar Gene Flow In Antarctic Silverfish (Pleuragramma Antarctica), Jilda Alicia Caccavo, Chiara Papetti, Maj Wetjen, Rainer Knust, Julian R. Ashford, Lorenzo Zane

OES Faculty Publications

The Antarctic silverfish (Pleuragramma antarctica) is a critically important forage species with a circumpolar distribution and is unique among other notothenioid species for its wholly pelagic life cycle. Previous studies have provided mixed evidence of population structure over regional and circumpolar scales. The aim of the present study was to test the recent population hypothesis for Antarctic silverfish, which emphasizes the interplay between life history and hydrography in shaping connectivity. A total of 1067 individuals were collected over 25 years from different locations on a circumpolar scale. Samples were genotyped at fifteen microsatellites to assess population differentiation and …

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Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis Dec 2018

Late Quaternary Evolution And Stratigraphic Framework Influence On Coastal Systems Along The North-Central Gulf Of Mexico, Usa, Robert Hollis

Master's Theses

Coastal systems in the Gulf of Mexico are threatened to reduced sediment supply, storm impacts and relative sea level rise (RSLR). The geologic record can provide insights of geomorphic threshold crossings (formation, progradation, transgression, destruction) to these forcing mechanisms to predict future barrier evolution to climate change. The stratigraphic framework and antecedent topography directly influence coastal evolution over geologic timescales. This study synthesizes ~2100km of geophysical data, 700+ sediment cores, and 63 radiocarbon dates to regionally map two sequence boundaries, multiple ravinement surfaces and fourteen depositional facies. One marine isotope stage (MIS) 6 valley’s fill provided up to 300 x10 …

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Symbiotic Unicellular Cyanobacteria Fix Nitrogen In The Arctic Ocean, K. Harding, K. A. Turk-Kubo, Rachel E. Sipler, M. M. Mills, D. A. Bronk Dec 2018

Symbiotic Unicellular Cyanobacteria Fix Nitrogen In The Arctic Ocean, K. Harding, K. A. Turk-Kubo, Rachel E. Sipler, M. M. Mills, D. A. Bronk

VIMS Articles

Biological dinitrogen (N2) fixation is an important source of nitrogen (N) in low-latitude open oceans. The unusual N2-fixing unicellular cyanobacteria (UCYN-A)/haptophyte symbiosis has been found in an increasing number of unexpected environments, including northern waters of the Danish Straight and Bering and Chukchi Seas. We used nanoscale secondary ion mass spectrometry (nanoSIMS) to measure 15N2 uptake into UCYN-A/haptophyte symbiosis and found that UCYN-A strains identical to low-latitude strains are fixing N2 in the Bering and Chukchi Seas, at rates comparable to subtropical waters. These results show definitively that cyanobacterial N2 fixation is not constrained to subtropical waters, challenging paradigms and …

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Lighting A Path To Biofouling Prevention: Investigating The Effect Of Ultraviolet Light On Biofouling, Cierra Rose Braga Dec 2018

Lighting A Path To Biofouling Prevention: Investigating The Effect Of Ultraviolet Light On Biofouling, Cierra Rose Braga

Theses and Dissertations

Ultraviolet light (UV) is considered an environmentally friendly antifouling method because it disrupts biological growth without the release of harmful toxins. The application of UV for the marine shipping industry is a relatively new concept, and there still remains many unknowns before it can be fully implemented. This research investigated several aspects of applying UVC for the control of fouling. A novel method of using embedded UV LEDs within a silicone coating for fouling control proved to be very effective at preventing fouling. The research also investigated the effect of using an external UVC light treatment to control fouling on …

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Dynamics Of Prochlorococcus Diversity And Photoacclimation During Short-Term Shifts In Water Column Stratification At Station Aloha, Anne W. Thompson, Ger Van Den Engh, Nathan A. Ahlgren, Kathleen Kouba, Samantha Ward, Samuel T. Wilson, David M. Karl Dec 2018

Dynamics Of Prochlorococcus Diversity And Photoacclimation During Short-Term Shifts In Water Column Stratification At Station Aloha, Anne W. Thompson, Ger Van Den Engh, Nathan A. Ahlgren, Kathleen Kouba, Samantha Ward, Samuel T. Wilson, David M. Karl

Biology Faculty Publications and Presentations

The cyanobacterium Prochlorococcus is the dominant phototroph in surface waters of the vast oligotrophic oceans, the foundation of marine food webs, and an important component of global biogeochemical cycles. The prominence of Prochlorococcus across the environmental gradients of the open ocean is attributed to its extensive genetic diversity and flexible chlorophyll physiology, enabling light capture over a wide range of intensities. What remains unknown is the balance between temporal dynamics of genetic diversity and chlorophyll physiology in the ability of Prochlorococcus to respond to a variety of short (approximately 1 day) and longer (months to year) changes in the environment. …

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Aliased Tidal Variability In Mesoscale Sea Level Anomaly Maps, Edward Zaron, Richard D. Ray Dec 2018

Aliased Tidal Variability In Mesoscale Sea Level Anomaly Maps, Edward Zaron, Richard D. Ray

Civil and Environmental Engineering Faculty Publications and Presentations

Sea level anomaly (SLA) maps are routinely produced by objective analysis of data from the constellation of satellite altimeter missions in operation since 1992. Beginning in 2014, changes in the Data Unification and Altimeter Combination System (DUACS) used to create the SLA maps resulted in improved spatial resolution of mesoscale variability, but it also increased the levels of aliased tidal variability compared to the methodology employed prior to 2014. The present work investigates the magnitude and spatial distribution of these tidal signals, which are typically smaller than 1 cmin the open ocean but can reach tens of centimeters in the …

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Associated Dataset: Ocean Circulation Causes Strong Variability In The Mid-Atlantic Bight Nitrogen Budget, Marjorie A.M. Friedrichs, Pierre St-Laurent Dec 2018

Associated Dataset: Ocean Circulation Causes Strong Variability In The Mid-Atlantic Bight Nitrogen Budget, Marjorie A.M. Friedrichs, Pierre St-Laurent

Data

The dataset includes model outputs used in the associated publication (Friedrichs et al.), which used the United States Eastern Continental Shelf (USECoS) biogeochemical model embedded in the Regional-Ocean-Modeling-System (ROMS) to examine the impact of the oceanic circulation on the nitrogen budget of the Mid-Atlantic Bight (MAB). The model simulation covers the period 2004 to 2008 and is fully described in the associated publication. The model simulation highlights that the horizontal along-shelf and across-shelf fluxes dominate the spatiotemporal variability of net community production (NCP) in the MAB. The highest NCP is found in a year when inorganic nitrogen entering from across …

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Evolution Of 21st Century Sea Level Rise Projections, Andra J. Garner, Jeremy L. Weiss, Adam Parris, Robert E. Kopp, Radley M. Horton, Jonathan T, Overpeck, Benjamin P. Horton Nov 2018

Evolution Of 21st Century Sea Level Rise Projections, Andra J. Garner, Jeremy L. Weiss, Adam Parris, Robert E. Kopp, Radley M. Horton, Jonathan T, Overpeck, Benjamin P. Horton

School of Earth & Environment Faculty Scholarship

The modern era of scientific global‐mean sea level rise (SLR) projections began in the early 1980s. In subsequent decades, understanding of driving processes has improved, and new methodologies have been developed. Nonetheless, despite more than 70 studies, future SLR remains deeply uncertain. To facilitate understanding of the historical development of SLR projections and contextualize current projections, we have compiled a comprehensive database of 21st century global SLR projections. Although central estimates of 21st century global‐mean SLR have been relatively consistent, the range of projected SLR has varied greatly over time. Among studies providing multiple estimates, the range of upper projections …

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Flux Of Particulate Elements In The North Atlantic Ocean Constrained By Multiple Radionuclides, Christopher T. Hayes, Erin E. Black, Robert F. Anderson, Mark Baskaran, Ken O. Buesseler, Matthew A. Charette, Hai Cheng, J. Kirk Cochran, R. Lawrence Edwards, Patrick Fitzgerald, Phoebe J. Lam, Yanbin Lu, Stephanie O. Morris, Daniel C. Ohnemus, Frank J. Pavia, Gillian Stewart, Yi Tang Nov 2018

Flux Of Particulate Elements In The North Atlantic Ocean Constrained By Multiple Radionuclides, Christopher T. Hayes, Erin E. Black, Robert F. Anderson, Mark Baskaran, Ken O. Buesseler, Matthew A. Charette, Hai Cheng, J. Kirk Cochran, R. Lawrence Edwards, Patrick Fitzgerald, Phoebe J. Lam, Yanbin Lu, Stephanie O. Morris, Daniel C. Ohnemus, Frank J. Pavia, Gillian Stewart, Yi Tang

Environmental Science and Geology Faculty Research Publications

Sinking particles strongly regulate the distribution of reactive chemical substances in the ocean, including particulate organic carbon and other elements (e.g., P, Cd, Mn, Cu, Co, Fe, Al, and 232Th). Yet, the sinking fluxes of trace elements have not been well described in the global ocean. The U.S. GEOTRACES campaign in the North Atlantic (GA03) offers the first data set in which the sinking flux of carbon and trace elements can be derived using four different radionuclide pairs (238U:234Th ;210Pb:210Po; 228Ra:228Th; and 234U:230Th) at stations co-located with sediment trap fluxes for comparison. Particulate organic carbon, particulate P, and particulate Cd …

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Impacts Of Pacific Ssts On Atmospheric Circulations Leading To California Winter Precipitation Variability: A Diagnostic Modeling, Boksoon Myoung, Sang-Wook Yeh, Jinwon Kim, Menas Kafatos Nov 2018

Impacts Of Pacific Ssts On Atmospheric Circulations Leading To California Winter Precipitation Variability: A Diagnostic Modeling, Boksoon Myoung, Sang-Wook Yeh, Jinwon Kim, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

One of the primary meteorological causes of the winter precipitation deficits and droughts in California (CA) is anomalous developments and maintenance of upper-tropospheric ridges over the northeastern Pacific. In order to understand and find the key factors controlling the winter precipitation variability in CA, the present study examines two dominant atmospheric modes of the 500 hPa geopotential height in the Northern Hemisphere using an Empirical Orthogonal Function (EOF) and their associated large-scale circulation patterns for the last 41 winters (1974/75–2014/15). Explaining 17.5% of variability, the second mode (EOF2) shows strong anti-cyclonic circulations in the North Pacific and cyclonic circulations in …

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Evaluation Of Spatial Generalization Characteristics Of A Robust Classifier As Applied To Coral Reef Habitats In Remote Islands Of The Pacific Ocean, Justin J. Gapper, Hesham El-Askary, Erik J. Linstead, Thomas Piechota Nov 2018

Evaluation Of Spatial Generalization Characteristics Of A Robust Classifier As Applied To Coral Reef Habitats In Remote Islands Of The Pacific Ocean, Justin J. Gapper, Hesham El-Askary, Erik J. Linstead, Thomas Piechota

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study was an evaluation of the spectral signature generalization properties of coral across four remote Pacific Ocean reefs. The sites under consideration have not been the subject of previous studies for coral classification using remote sensing data. Previous research regarding using remote sensing to identify reefs has been limited to in-situ assessment, with some researchers also performing temporal analysis of a selected area of interest. This study expanded the previous in-situ analyses by evaluating the ability of a basic predictor, Linear Discriminant Analysis (LDA), trained on Depth Invariant Indices calculated from the spectral signature of coral in one location …

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Resource Assessment Report Temperate Demersal Elasmobranch Resource Of Western Australia, Matias Braccini, Nick Blay, S. A. Hesp, Brett Molony Nov 2018

Resource Assessment Report Temperate Demersal Elasmobranch Resource Of Western Australia, Matias Braccini, Nick Blay, S. A. Hesp, Brett Molony

Fisheries research reports

This document provides a cumulative description and assessment of the TDER and all of the fishing activities (i.e. fisheries / fishing sectors) affecting this resource in WA. Future Resource Assessment Reports will assess the Statewide Sharks and Rays Resource. The report is focused on the temperate indicator species (whiskery, gummy, dusky and sandbar sharks) used to assess the suites of demersal sharks and rays that comprise this resource. These species are primarily captured by demersal gillnets used in the TDGDLF that operate in the West Coast and South Coast Bioregions. For the North Coast bioregion, no commercial fishing for sharks …

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A Deep Eastern Equatorial Pacific Thermocline During The Last Glacial Maximum, H. L. Ford, C. L. Mcchesney, J. E. Hertzberg, J. F. Mcmanus Nov 2018

A Deep Eastern Equatorial Pacific Thermocline During The Last Glacial Maximum, H. L. Ford, C. L. Mcchesney, J. E. Hertzberg, J. F. Mcmanus

OES Faculty Publications

The mean state and variability of the tropical Pacificis influenced by the depth of the thermocline. During the Last Glacial Maximum (~21,000 years ago), the zonal sea surface temperature gradient across the equatorial Pacific was reduced and productivity was generally lower than modern. To understand the thermocline depth’s role in determining the Last Glacial Maximum tropical mean state, we reconstruct the upper ocean δ18O profile from multiple species of planktic foraminifera. We synthesize existing records of surface and subsurface dwelling foraminifera to reconstruct the vertical δ18O gradient throughout the eastern equatorial Pacific. We find the thermocline …

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Ground-Truthing Social Vulnerability Indices Of Alaska Fishing Communities, Anna Lavoie, Kim Sparks, Stephen Kasperski, Amber Himes-Cornell, Kristin Hoelting, Conor Maguire Oct 2018

Ground-Truthing Social Vulnerability Indices Of Alaska Fishing Communities, Anna Lavoie, Kim Sparks, Stephen Kasperski, Amber Himes-Cornell, Kristin Hoelting, Conor Maguire

All Faculty Scholarship for the College of the Sciences

Community vulnerability is increasingly evaluated through quantitative social indices, typically developed using secondary data sources rather than primary data collection. It is necessary to understand the validity of these indices if they will be used to inform policy and decision making. This paper presents a ground-truthing effort to validate quantitative indices that characterize the well-being of Alaska fishing communities. We utilized ethnographic data collected from 13 representative communities and a capital assets framework to ground-truth the indices, in which qualitative ranks of vulnerability were compared against quantitative indices. The majority (73.8%) of ranks were in complete or moderate agreement and …

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Mid-Pliocene To Early Pleistocene Sea Surface And Land Temperature History Of Nw Australia Based On Organic Geochemical Proxies From Site U1463, Rebecca Smith Oct 2018

Mid-Pliocene To Early Pleistocene Sea Surface And Land Temperature History Of Nw Australia Based On Organic Geochemical Proxies From Site U1463, Rebecca Smith

Masters Theses

Ocean gateways facilitate water circulation between ocean basins, and therefore directly impact thermohaline circulation and global climate. In order to better predict the effects of future climate change, it is critical to constrain past changes in ocean gateway behavior, and corresponding changes in thermohaline circulation, particularly during analogue periods for modern climate change. The Indonesian Throughflow (ITF) is a primary ocean gateway and vital component of the global conveyor that transports water from the Pacific Ocean into the Indian Ocean, however due to a lack of long and continuous sedimentary records from locations under its influence, changes in ITF behavior …

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A Model Archive For Sediment Transport Model Including Short-Lived Radioisotopes: Model Description And Idealized Test Cases, Justin J. Birchler, Courtney K. Harris, Tara A. Kniskern Oct 2018

A Model Archive For Sediment Transport Model Including Short-Lived Radioisotopes: Model Description And Idealized Test Cases, Justin J. Birchler, Courtney K. Harris, Tara A. Kniskern

Data

This dataset includes model input, code, and output used in the publication Birchler et al. (2018, Journal of Marine Science and Engineering), which used a coupled hydrodynamic-sediment transport-biogeochemical model to investigate the roles of resuspension, deposition, on biodiffusion on the behavior of short-lived radioisotopes in an idealized one-dimensional model setting. Model development for this project focused on incorporating radioisotope tracers into the sediment transport module in the Regional Ocean Modeling System (ROMS). As described in Birchler et al. (2018, Journal of Marine Science and Engineering), the model can account for supply and sorption of radioisotope tracers in the …

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Eddy Flux Measurements Of Sulfur Dioxide Deposition To The Sea Surface, Jack G. Porter, Warren J. De Bruyn, Eric S. Saltzman Oct 2018

Eddy Flux Measurements Of Sulfur Dioxide Deposition To The Sea Surface, Jack G. Porter, Warren J. De Bruyn, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Deposition to the sea surface is a major atmospheric loss pathway for many important trace gases, such as sulfur dioxide (SO2). The air–sea transfer of SO2 is controlled entirely on the atmospheric side of the air–sea interface due to high effective solubility and other physical– chemical properties. There have been few direct field measurements of such fluxes due to the challenges associated with making fast-response measurements of highly soluble trace gases at very low ambient levels. In this study, we report direct eddy covariance air–sea flux measurements of SO2, sensible heat, water vapor, and momentum. The measurements were made over …

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Tidal-, Wind-, And Buoyancy-Driven Dynamics In The Barataria Estuary And Its Impact On Estuarine-Shelf Exchange Processes, Linlin Cui Oct 2018

Tidal-, Wind-, And Buoyancy-Driven Dynamics In The Barataria Estuary And Its Impact On Estuarine-Shelf Exchange Processes, Linlin Cui

LSU Doctoral Dissertations

A three-dimensional, high-resolution, Finite-Volume Coastal Ocean Model (FVCOM) was used to study the dynamics of Barataria Estuary located in the Southeastern Louisiana. Three numerical experiments with different discharge scenarios, including the actual discharge (average ~ 160 m3 s-1) from the Davis Pond Diversion (DPD) over three months from April to June 2010, no discharge (NO), and the proposed Mid-Barataria Diversion (MBD) with a constant discharge of 850 m3 s-1, were conducted to investigate the impacts of river diversions on salinity gradients and residence times in the estuary. The three-month average salinity indicated that surface …

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Stormsense: A Blueprint For Coastal Flood Forecast Information & Automated Alert Messaging Systems, Jon Derek Loftis, Sridhar Katragadda, Sokwoo Rhee, Cuong Nguyen Oct 2018

Stormsense: A Blueprint For Coastal Flood Forecast Information & Automated Alert Messaging Systems, Jon Derek Loftis, Sridhar Katragadda, Sokwoo Rhee, Cuong Nguyen

VIMS Articles

Increased availability of low-cost water level sensors communicating through the Internet of Things (IoT) has expanded the horizons of publicly-ingestible data streams available to modern smart cities. StormSense is an IoT-enabled inundation forecasting research initiative and an active participant in the Global City Teams Challenge seeking to enhance flood preparedness in the smart cities of Hampton Roads, VA for flooding resulting from storm surge, rain, and tides. In this study, we present the a blueprint and series of applicable protocols through the use of the new StormSense water level sensors to help establish a regional resilience monitoring network. In furtherance …

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Effects Of Density‐Driven Flows On The Long‐Term Morphodynamic Evolution Of Funnel‐Shaped Estuaries, Matiane Olabarrieta, W. Rockwell Geyer, Giovanni Coco, Carl T. Friedrichs Oct 2018

Effects Of Density‐Driven Flows On The Long‐Term Morphodynamic Evolution Of Funnel‐Shaped Estuaries, Matiane Olabarrieta, W. Rockwell Geyer, Giovanni Coco, Carl T. Friedrichs

VIMS Articles

Subtidal flows driven by density gradients affect the tide‐averaged sediment transport in estuaries and, therefore, can influence their long‐term morphodynamic evolution. The three‐dimensional Coupled Ocean‐Atmosphere‐Wave‐Sediment Transport modeling system is applied to numerically analyze the effects of baroclinicity and Earth's rotation on the long‐term morphodynamic evolution of idealized funnel‐shaped estuaries. The morphodynamic evolution in all the analyzed cases reproduced structures identified in many tide‐dominated estuaries: a meandering region in the fluvial‐tidal transition zone, a tidal maximum area close to the head, and a turbidity maxima region in the brackish zone. As the morphology of the estuaries evolved, the tidal propagation (including …

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Impact Of Seabed Resuspension On Oxygen And Nitrogen Dynamics In The Northern Gulf Of Mexico: A Numerical Modeling Study, Julia M. Moriarty, Courtney K. Harris, Marjorie A.M. Friedrichs, Katja Fennel, Kehui Xu Oct 2018

Impact Of Seabed Resuspension On Oxygen And Nitrogen Dynamics In The Northern Gulf Of Mexico: A Numerical Modeling Study, Julia M. Moriarty, Courtney K. Harris, Marjorie A.M. Friedrichs, Katja Fennel, Kehui Xu

VIMS Articles

Resuspension affects water quality in coastal environments by entraining seabed organic matter into the water column, which can increase remineralization, alter seabed fluxes, decrease water clarity, and affect oxygen and nutrient dynamics. Nearly all numerical models of water column biogeochemistry, however, simplify seabed and bottom boundary layer processes and neglect resuspension. Here we implemented HydroBioSed, a coupled hydrodynamic-sediment transport-biogeochemical model to examine the role of resuspension in regulating oxygen and nitrogen dynamics on timescales of a day to a month. The model was implemented for the northern Gulf of Mexico, where the extent of summertime hypoxia is sensitive to seabed …

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Correlations Between Reef Health And Vertical Zonation On Ushongo Village Reef And Fungu Zinga Reef, Daniel Gates Oct 2018

Correlations Between Reef Health And Vertical Zonation On Ushongo Village Reef And Fungu Zinga Reef, Daniel Gates

Independent Study Project (ISP) Collection

While the existence of vertical zonation on coral reefs is well-known, the driving mechanisms and the influence each has is not clear. This study seeks to investigate the influence of reef health on vertical zonation. Reef health is used as a potential factor since it is essentially a broad description of reef diversity. Therefore, a healthy reef which is very diverse is likely to have more and different interspecies interactions than an unhealthy one. This project investigates whether these altered interactions results in different depth distributions of various coral types, categorized broadly by colony shape. Reef health did not seem …

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The Influence Of Habitat Preference On Longitudinal Population Composition And Distribution Of Groupers (Serranidae) In Chumbe Island Coral Park, Zanzibar Tanzania, Caroline Daley Oct 2018

The Influence Of Habitat Preference On Longitudinal Population Composition And Distribution Of Groupers (Serranidae) In Chumbe Island Coral Park, Zanzibar Tanzania, Caroline Daley

Independent Study Project (ISP) Collection

A survey of six common grouper (Serranidae) species was conducted on both the western protected and eastern unprotected reefs around Chumbe Island. Species, estimated maturity, and fundamental niche and general habitat preference was extrapolated based on observed realized niche and qualified according to substrate, depth, slope position, and general reef region. Abundance, biomass density, and biodiversity of Serranid populations were compared among locations on the reef with habitat preference in mind in order to best assess how habitat influences population composition, distribution, and health. The results of this study provide depth to previous research on the protected reef and indicate …

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Characterizing Diatom Biofilms And Their Influence On The Sand Biogeochemistry Of High Energy Beaches, Logan C. Jarrell Oct 2018

Characterizing Diatom Biofilms And Their Influence On The Sand Biogeochemistry Of High Energy Beaches, Logan C. Jarrell

Honors Theses

High energy beaches are among the most dynamic ecological settings on Earth. Compared to mudflats, diatoms of high energy beaches have been more neglected in the literature, particularly true of the intertidal biofilms that form and dissipate with nutrient cycling and light intensity over the tidal cycle. Although short lived, the productivity of these biofilms may be critical to the organic-poor sand. Through sediment coring and subsequent analyses of the uppermost sand of three suspected biofilm stations—non-runnel, runnel crest, and runnel trough—along with seemingly bare sand as a control, this study sought to verify the presence of diatom biofilms and …

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