Physical Sciences and Mathematics Commons^™

Relative Influence Of Antecedent Topography And Sea-Level Rise On Barrier-Island Migration: Sediment Core Data, Justin L. Shawler, Jennifer E. Connell, Bianca Q. Boggs, Christopher J. Hein

Data

No abstract provided.

Data-Driven, Multi-Model Workflow Suggests Strong Influence From Hurricanes On The Generation Of Turbidity Currents In The Gulf Of Mexico, Courtney K. Harris, Jaia Syvitski, H. G. Arango, Et Al

VIMS Articles

Turbidity currents deliver sediment rapidly from the continental shelf to the slope and beyond; and can be triggered by processes such as shelf resuspension during oceanic storms; mass failure of slope deposits due to sediment- and wave-pressure loadings; and localized events that grow into sustained currents via self-amplifying ignition. Because these operate over multiple spatial and temporal scales, ranging from the eddy-scale to continental-scale; coupled numerical models that represent the full transport pathway have proved elusive though individual models have been developed to describe each of these processes. Toward a more holistic tool, a numerical workflow was developed to address …

Farm Resiliency Education For At-Risk Coastal Areas In The Chesapeake Bay, Kristen Saacke Blunk, Kristen Hughes Evans, Jennifer Miller Herzog, Julie Herman, Carl Hershner, Donna Bilkovic, Kirk J. Havens

Reports

The Virginia Institute of Marine Science (VIMS) in collaboration with its partners, the Land Trust Alliance, Sustainable Chesapeake, and The Nature Conservancy, explored and refined questions critical for advising and guiding landowners who farm within coastal areas that are vulnerable to sea level rise and saltwater intrusion, and ultimately, loss of arable cropland in the Chesapeake Bay watershed. While the questions posed are those that agricultural experts across the coastal zones are struggling with, this effort focused on identifying the current state of the science and informational gaps; building current, best professional guidance for landowner conservation program choices; and developing …

Demonstration Of The Lateral Ac Skin Effect Using A Pickup Coil, Anne E. Blackwell, Andrew P. Rotunno, Seth Aubin

Arts & Sciences Articles

We present a simple demonstration of the skin effect by observing the current distribution in a wide rectangular strip conductor driven at frequencies in the 0.25–5 kHz range. We measure the amplitude and phase of the current distribution as a function of the transverse position and find that they agree well with numerical simulations: The current hugs the edges of the strip conductor with a significant variation in phase across the width. The experimental setup is simple, uses standard undergraduate physics instructional laboratory equipment, and is easy to implement as a short in-class demonstration. Our study is motivated by modeling …

Sediment Delivery To A Tidal Marsh Platform Is Minimized By Source Decoupling And Flux Convergence, Daniel J. Coleman, Neil K. Ganju, Matthew L. Kirwan

VIMS Articles

Sediment supply is a primary factor in determining marsh response to sea level rise and is typically approximated through high‐resolution measurements of suspended sediment concentrations (SSCs) from adjacent tidal channels. However, understanding sediment transport across the marsh itself remains limited by discontinuous measurements of SSC over individual tidal cycles. Here, we use an array of optical turbidity sensors to build a long‐term, continuous record of SSC across a marsh platform and adjacent tidal channel. We find that channel and marsh concentrations are correlated (i.e., coupled) within tidal cycles but are largely decoupled over longer time scales. We also find that …

Relative Impacts Of Global Changes And Regional Watershed Changes On The Inorganic Carbon Balance Of The Chesapeake Bay, Pierre St-Laurent, Marjorie A.M. Friedrichs, Raymond G. Najjar, Elizabeth Shadwick, Hanquin Tian, Yuanzhi Yao

VIMS Articles

The Chesapeake Bay is a large coastal-plain estuary that has experienced considerable anthropogenic changeover the past century. At the regional scale, land-use change has doubled the nutrient input from rivers and led to an increase in riverine carbon and alkalinity. The bay has also experienced global changes, including the rise of atmospheric temperature and CO2. Here we seek to understand the relative impact of these changes on the inorganic carbon balance of the bay between the early 1900s and the early 2000s. We use a linked land–estuarine–ocean modeling system that includes both inorganic and organic carbon and nitrogen cycling. Sensitivity …

Challenges In Quantifying Air‐Water Carbon Dioxide Flux Using Estuarine Water Quality Data: Case Study For Chesapeake Bay, Marie Herrmann, Raymond G. Najjar, Fei Da, Marjorie A.M. Friedrichs, Sreece Goldberger, Alana Menendez, Elizabeth Shadwick, Pierre St-Laurent

VIMS Articles

Estuaries play an uncertain but potentially important role in the global carbon cycle via CO₂ outgassing. The uncertainty mainly stems from the paucity of studies that document the full spatial and temporal variability of estuarine surface water partial pressure of carbon dioxide ( p CO₂). Here, we explore the potential of utilizing the abundance of pH data from historical water quality monitoring programs to fill the data void via a case study of the mainstem Chesapeake Bay (eastern United States). We calculate p CO₂ and the air‐water CO₂ flux at monthly resolution from 1998 to …

A Convolutional Neural Network Approach To Predict Non-Permissive Environments From Moderate-Resolution Imagery, Seth Goodman, Ariel Benyishay, Daniel Runfola

Arts & Sciences Articles

Convolutional neural networks (CNNs) trained with satellite imagery have been successfully used to generate measures of development indicators, such as poverty, in developing nations. This article explores a CNN-based approach leveraging Landsat 8 imagery to predict locations of conflict-related deaths. Using Nigeria as a case study, we use the Armed Conflict Location & Event Data (ACLED) dataset to identify locations of conflict events that did or did not result in a death. Imagery for each location is used as an input to train a CNN to distinguish fatal from non-fatal events. Using 2014 imagery, we are able to predict the …

Flame Retardants, Dioxins, And Furans In Air And On Firefighters’ Protective Ensembles During Controlled Residential Firefighting, Kenneth W. Fent, Mark J. La Guardia, Drew Luellen, Et Al

VIMS Articles

Structure fires that involve modern furnishings may emit brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs), as well as brominated and chlorinated dioxins and furans, into the environment.

The goal of this study was to quantify the airborne and personal protective equipment (PPE) contamination levels of these compounds during controlled residential fires in the U.S., and to evaluate gross-decontamination measures.

Associated Dataset: Relative Impacts Of Global Changes And Regional Watershed Changes On The Inorganic Carbon Balance Of The Chesapeake Bay, Pierre St-Laurent, Marjorie A.M. Friedrichs

Data

The dataset is a permanent archive of the results presented in the associated publication (St-Laurent et al. 2020, Biogeosciences).

This study used a biogeochemical module embedded in the Regional Ocean Modeling System (ROMS) to examine the relative impacts of global changes and regional watershed changes on the inorganic carbon balance of the Chesapeake Bay over the past century. The numerical experiments contrast the periods 1900-1914 and 2000-2014 and the results are fully described in the associated publication.

Single-Use Plastics And Covid-19: Scientific Evidence And Environmental Regulations, Robert C. Hale, Bk Song

VIMS Articles

Waste plastics are a serious and growing environmental problem. Less than 10% of plastics are recycled, with most discarded in landfills, incinerated, or simply abandoned.1 Single-use plastics constitute about half of plastic waste. While most plastics are used and initially disposed of on land, much eventually enters aquatic ecosystems.2 Wildlife mortalities result from encounters (e.g., ingestion and entanglement) with large debris, including plastic bags. Such bags are excluded from many recycling programs, as they can entangle machinery. Most plastics do not readily biodegrade in the environment. However, they can be embrittled by UV exposure and fragment into microplastics (mm) and …

Zooplankton Diel Vertical Migration During Antarctic Summer, John A. Conroy, Deborah K. Steinberg, Patrica S. Thibodeau, Oscar Schofield

VIMS Articles

Zooplankton diel vertical migration (DVM) during summer in the polar oceans is presumed to be dampened due to near continuous daylight. We analyzed zooplankton diel vertical distribution patterns in a wide range of taxa along the Western Antarctic Peninsula (WAP) to assess if DVM occurs, and if so, what environmental controls modulate DVM in the austral summer. Zooplankton were collected during January and February in paired day-night, depth-stratified tows through the mesopelagic zone along the WAP from 2009-2017, as well as in day and night epipelagic net tows from 1993-2017. The copepod Metridia gerlachei, salp Salpa thompsoni, pteropod …

Measurement Of The 3he Spin-Structure Functions And Of Neutron (3he) Spin-Dependent Sum Rules At 0.035 ≤ Q2 ≤ 0.24 Gev2, Jefferson Lab E97-110 Collaboration, David S. Armstrong

Arts & Sciences Articles

The spin-structure functions g1 and g2, and the spin-dependent partial cross-section σTT have been extracted from the polarized cross-sections differences, σ| ν, Q 2 and σ⊥ ν, Q 2 measured for the 3 > He(e>, e' )X reaction, in the E97-110 experiment at Jefferson Lab. Polarized electrons with energies from 1.147 to 4.404 GeV were scattered at angles of 6◦ and 9◦ from a longitudinally or transversely polarized 3He target. The data cover the kinematic regions of the quasi-elastic, resonance production and beyond. From the extracted spin-structure functions, the first moments 1 (Q2) , 2 (Q2) and ITT Q 2 …

Constraining An Ocean Model Under Getz Ice Shelf, Antarctica, Using A Gravity‐Derived Bathymetry, Romain Millan, Pierre St-Laurent, Eric Rignot, Et Al

VIMS Articles

Getz Ice Shelf, the largest producer of ice shelf meltwater in Antarctica, buttresses glaciers that hold enough ice to raise sea level by 22 cm. We present a new bathymetry of its sub‐ice shelf cavity using a three‐dimensional inversion of airborne gravity data constrained by multibeam bathymetry at sea and a reconstruction of the bedrock from mass conservation on land. The new bathymetry is deeper than previously estimated with differences exceeding 500 m in a number of regions. When incorporated into an ocean model, it yields a better description of the spatial distribution of ice shelf melt, specifically along glacier …

Current And Future Remote Sensing Of Harmful Algal Blooms In The Chesapeake Bay To Support The Shellfish Industry, Jl Wolny, Mc Tomlinson, S Schollaert Uz, Ta Egerton, Jr Mckay, A Meredith, Ks Reece, Gp Scott, Rp Stumpf

VIMS Articles

Harmful algal bloom (HAB) species in the Chesapeake Bay can negatively impact fish, shellfish, and human health via the production of toxins and the degradation of water quality. Due to the deleterious effects of HAB species on economically and environmentally important resources, such as oyster reef systems, Bay area resource managers are seeking ways to monitor HABs and water quality at large spatial and fine temporal scales. The use of satellite ocean color imagery has proven to be a beneficial tool for resource management in other locations around the world where high-biomass, nearly monospecific HABs occur. However, remotely monitoring HABs …

The Impact Of Winter Storms On Sediment Transport Through A Narrow Strait, Bohai, China, Chenghao Wang, Zhiqiang Liu, Courtney K. Harris, Et Al

VIMS Articles

The Yellow River is one of the most significant sources of terrestrial sediment to the global seas, and the Bohai Strait is the only pathway that delivers Yellow River‐derived sediments from the shallow Bohai Sea to the Yellow Sea. To investigate sediment transport processes through the strait under the influence of storms (strong northerly winds) that frequently occur in winter, we deployed two sets of observing platforms equipped with Acoustic Doppler Current Profilers (ADCP) and a suite of other sensors in the strait in January 2018. Aided by a system of high‐resolution models, we reconstructed sediment dynamics in response to …

Representing The Function And Sensitivity Of Coastal Interfaces In Earth System Models, Nd Ward, Jp Megonigal, B Bond-Lamberty, Vl Bailey, D Butman, Elizabeth A. Canuel, Et Al

VIMS Articles

Between the land and ocean, diverse coastal ecosystems transform, store, and transport material. Across these interfaces, the dynamic exchange of energy and matter is driven by hydrological and hydrodynamic processes such as river and groundwater discharge, tides, waves, and storms. These dynamics regulate ecosystem functions and Earth's climate, yet global models lack representation of coastal processes and related feedbacks, impeding their predictions of coastal and global responses to change. Here, we assess existing coastal monitoring networks and regional models, existing challenges in these efforts, and recommend a path towards development of global models that more robustly reflect the coastal interface. …

Crowdsourcing Street View Imagery: A Comparison Of Mapillary And Openstreetcam, Ron Mahabir, Ross Schuchard, Andrew Crooks, Arie Croitoru, Anthony Stefanidis

Arts & Sciences Articles

Over the last decade, Volunteered Geographic Information (VGI) has emerged as a viable source of information on cities. During this time, the nature of VGI has been evolving, with new types and sources of data continually being added. In light of this trend, this paper explores one such type of VGI data: Volunteered Street View Imagery (VSVI). Two VSVI sources, Mapillary and OpenStreetCam, were extracted and analyzed to study road coverage and contribution patterns for four US metropolitan areas. Results show that coverage patterns vary across sites, with most contributions occurring along local roads and in populated areas. We also …

Providential Tides: The Double Low Water Of Narragansett Bay, D. G. Bowers, J. M. Brubaker

VIMS Articles

We investigate a mechanism for producing double-lows and double-highs in the semi-diurnal tide by selective amplification of higher harmonics in a resonant gulf. A double low water is observed at Providence, RI, near the head of Narragansett Bay on days when there is a flattening of the low water tidal curve at Newport, at the mouth of the bay. The flattening is caused by an unusually large quarter-diurnal component to the tide at Newport. The quarter diurnal component has the right phase (a maximum close to the time of the minimum in the semi-diurnal tide) to produce a prolonged flattening …

Virginia Game Fish Tagging Program Annual Report 2019, Susanna Musick, Lewis Gillingham

Reports

Through 2019, the Virginia Game Fish Tagging Program (VGFTP) has maintained a 24-year database of records for tagged and recaptured fish. The program is a cooperative project of the Virginia Saltwater Fishing Tournament (VSFT) under the Virginia Marine Resources Commission-(VMRC) and the Virginia Institute of Marine Science (VIMS) of the College of William and Mary (under the VIMS Marine Advisory Program).

Vims 2019 Potomac River Estuary Data In Support Of: Improved Penetrometer Performance In Stratified Sediment For Cost-Effective Characterization, Monitoring And Management Of Submerged Munitions Sites (Serdp Project: Mr18-1233), Grace M. Massey, Cristin L. Wright, Carl T. Friedrichs, Nina Stark, Dennis Kiptoo

Data

This work complements the efforts by the Virginia Tech Department of Civil & Environmental Engineering in SERDP MR18-1233, as described in the project’s final report (Stark et al, 2020) and in the Master’s thesis by Dennis Kiptoo (Kiptoo, 2020). Previous work on this project, conducted in the York River during 2018-2918 worked to improve calibration of the Bluedrop free fall penetrometer (FFP) with high resolution sampling of a variety of sediment types (Massey et al, 2020a). Calibration methods developed (Kiptoo, 2020) were used to rapidly identify different sediment types from a grid of 59 Bluedrop PPF stations sampled on the …

Vims 2019 York River Estuary Data In Support Of: Improved Penetrometer Performance In Stratified Sediment For Cost-Effective Characterization, Monitoring And Management Of Submerged Munitions Sites (Serdp Project: Mr18-1233), Grace M. Massey, Cristin L. Wright, Carl T. Friedrichs, Nina Stark, Dennis Kiptoo

Data

This work complements the efforts by the Virginia Tech Department of Civil & Environmental Engineering in SERDP MR18-1233, as described in the project’s final report (Stark et al, 2020) and in the Master’s thesis by Dennis Kiptoo (Kiptoo, 2020). One of the objectives of the project was to improve calibration of the Bluedrop free fall penetrometer (FFP) with high resolution sampling of a variety of sediment types. To accomplish this, a series of 9 stations over 12 cruises were visited along the York River, an estuary in the Virginia portion of the Chesapeake Bay, and in the Pamunkey River, which …

Parity-Violating Inelastic Electron-Proton Scattering At Low Q^2 Above The Resonance Region, D. Androic, David S. Armstrong, Qweak Collaboration

Arts & Sciences Articles

We report the measurement of the parity-violating asymmetry for the inelastic scattering of electrons from the proton, at Q2=0.082GeV2 and W=2.23 GeV, above the resonance region. The result AInel=−13.5±2.0(stat)±3.9(syst) ppm agrees with theoretical calculations, and helps to validate the modeling of the γZ interference structure functions FγZ1 and FγZ2 used in those calculations, which are also used for determination of the two-boson exchange γ−Z box diagram (□γZ) contribution to parity-violating elastic scattering measurements. A positive parity-violating asymmetry for inclusive π− production was observed, as well as positive beam-normal single-spin asymmetry for scattered electrons and a negative beam-normal single-spin asymmetry for …

Geoboundaries: A Global Database Of Political Administrative Boundaries, Daniel Runfola, Austin Anderson, Heather Baier, Matt Crittenden, Elizabeth Dowker, Seth Goodman, Et Al.

Arts & Sciences Articles

We present the geoBoundaries Global Administrative Database (geoBoundaries): an online, open license resource of the geographic boundaries of political administrative divisions (i.e., state, county). Contrasted to other resources geoBoundaries (1) provides detailed information on the legal open license for every boundary in the repository, and (2) focuses on provisioning highly precise boundary data to support accurate, replicable scientific inquiry. Further, all data is released in a structured form, allowing for the integration of geoBoundaries with large-scale computational workflows. Our database has records for every country around the world, with up to 5 levels of administrative hierarchy. The database is accessible …

Shoreline Management Handbook, Pamela Mason, Angela King, Clay Bernick

Reports

Shoreline habitats and processes are impacted by the decisions we make about managing coastal development and shorelines. Shoreline Management is making choices to address the desire to protect upland property from erosion or develop property balanced with the benefits and uses of natural and nature-based shoreline features and shoreline habitat restoration. This requires a weighing of the private benefits and cots of management actions and the benefits and costs to public held common resources, also known as the public trust. The natural features along our shorelines -tidal wetlands, beaches and dunes, and riparian buffers, are economically and ecologically valuable. They …

Massive Pollutants Released To Galveston Bay During Hurricane Harvey: Understanding Their Retention And Pathway Using Lagrangian Numerical Simulations, Jiabi Du, Kyeong Park, Xin Yu, Yinglong J. Zhang, Fei Ye

VIMS Articles

Increasing frequency of extreme precipitation events under the future warming climate makes the storm-related pollutant release more and more threatening to coastal ecosystems. Hurricane Harvey, a 1000-year extreme precipitation event, caused massive pollutant release from the Houston metropolitan area to the adjacent Galveston Bay. 0.57 × 10⁶ tons of raw sewage and 22,000 barrels of oil, refined fuels and chemicals were reportly released during Harvey, which would likely deteriorate the water quality and damage the coastal ecosystem. Using a Lagrangian particle-tracking method coupled with a validated 3D hydrodynamic model, we examined the retention, pathway, and fate of the released …

Surface Water Nitrogen Attenuation From The Accomack County, Va Southern Landfill Groundwater Discharge, Richard A. Snyder, Paige G. Ross

Reports

Previous sampling of the stream crossing Bobtown Road (Rt 178) near the intersection of Hollies Church Road (Rt. 620), had indicated high levels of nitrogen in the stream flow (Snyder and Ross, 2019a). The proximity of the retired Accomack County Landfill upstream of the site triggered a higher resolution sampling of the stream in an attempt to isolate a source of the nitrogen loading (Snyder and Ross, 2019b). Accomack County has requested repeated sampling of this stream segment to monitor nutrient attenuation trends from the site, and stations were established for that purpose. This is the first report of that …

Response Of Stratification Processes To Tidal Current Alteration Due To Channel Narrowing And Deepening, Lei Zhu, Qing He, Jian Shen

VIMS Articles

Stratification in estuaries has received much focus due to its importance in estuarine hydrodynamics and material transport. By utilizing a well‐calibrated numerical model, in this work we investigate the changes in stratification in the deepened and narrowed North Passage of the Changjiang Estuary. Before channel narrowing and deepening, lateral straining, generated by the interaction between vertical shear in lateral flow and transverse salinity gradient, is the dominant factor that controls stratification. A two‐layer structure of the lateral flow strains the isopycnal transversely, resulting in rapid stratification from late flood to early ebb tide. Thus, maximum stratification occurs during the early …

Impacts Of Seagrass Dynamics On The Coupled Long‐Term Evolution Of Barrier‐Marsh‐Bay Systems, I.R.B. Reeves, L. J. Moore, E. B. Goldstein, A. B. Murray, Matthew L. Kirwan

VIMS Articles

Seagrass provides a wide range of economically and ecologically valuable ecosystem services, with shoreline erosion control often listed as a key service, but can also alter the sediment dynamics and waves within back‐barrier bays. Here we incorporate seagrass dynamics into an existing barrier‐marsh exploratory model, GEOMBEST++, to examine the coupled interactions of the back‐barrier bay with both adjacent (marsh) and nonadjacent (barrier island) subsystems. While seagrass reduces marsh edge erosion rates and increases progradation rates in many of our 288 model simulations, seagrass surprisingly increases marsh edge erosion rates when sediment export from the back‐barrier basin is negligible because the …

Monitoring The Abundance Of American Shad And River Herring In Virginia's Rivers - 2019 Annual Report, Eric J. Hilton, Robert Latour, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee

Reports

This report describes the results of the twenty-second year of a continuing study to estimate the relative abundance and assess the status of American shad (Alosa sapidissima) stocks in Virginia by monitoring the spawning runs in the James, York and Rappahannock rivers in spring 2019, evaluating hatchery programs, and contributing to coast-wide assessments (ASMFC 2007). We also report on two fishery-independent monitoring programs using anchor gillnets in the Rappahannock River (year 2) and the Chickahominy River (year 5; a major tributary of the James River), to determine relative abundance and stock structure for the adult spawning run of river herring …