Physical Sciences and Mathematics Commons^™

Contrasting Hydrodynamic Responses To Atmospheric Systems With Different Scales: Impact Of Cold Fronts Vs. That Of A Hurricane, Wei Huang, C. Li

VIMS Articles

In this paper, subtidal responses of Barataria Bay to an atmospheric cold front in 2014 and Hurricane Barry of 2019 are studied. The cold fronts had shorter influencing periods (1 to 3 days), while Hurricane Barry had a much longer influencing period (about 1 week). Wind direction usually changes from southern quadrants to northern quadrants before and after a cold front’s passage. For a hurricane making its landfall at the norther Gulf of Mexico coast, wind variation is dependent on the location relative to the location of landfall. Consequently, water level usually reaches a trough after the maximum cold front …

Fate Of Ayeyarwady And Thanlwin River Sediment: Relative Importance Of Oceanographic And Tectonic Controls - Associated Dataset, Steven Kuehl, Courtney K. Harris

Data

Data set archive associated with Kuehl et al. (2019) collected as part of NSF award OCE-1737221. Core and CTD data are from a two-week oceanographic research cruise which was conducted in December 2017 in the Northern Andaman Sea and Bay of Bengal, using a locally hired vessel. Overall, we occupied 30 stations and collected ~50 sediment cores (kasten, gravity and box), along with CTD profiles on the shelf and inside the Yangon River estuary. The area covered includes both the western and eastern sides of the delta, almost 250 nm across, and southward across the continental shelf to a major …

Aberdeen Creek Dredge Channel Data Report, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Nicholas J. Dinapoli

Reports

Aberdeen Creek is located on the York River in Gloucester County, Virginia (Figure 1). At the narrow confluence of the York and Aberdeen, the creek takes about a 90-degree bend to the north (Figure 2) and widens to about 700 to 800 feet (ft) for about 2,000 ft. The creek then divides into two branches, one continuing north and one going east. These two prongs narrow quickly and become thin meandering tidal channels with adjacent marsh. The land use around the creek is mostly agricultural and wooded with some residential properties along its east side and along the York River …

Hog Island Shore Protection And Habitat Restoration Living Shoreline Project, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Nicholas J. Dinapoli

Reports

Hog Island is an emergent estuarine marsh complex that is part of the overall Guinea marshes (Figure 1). These marshes are located at the confluence of Mobjack Bay and the York River in Gloucester County, Virginia. Hog Island is a high wave energy eroding shoreline along its south-face on the York River, and lower wave energy along its west and east flanks that occur on Monday Creek (Figure 2). The marsh consists mainly of grasses such as Spartina alterniflora and Spartina patens. A higher, sandy area along the higher energy shorelines has some scrub shrub. Two small ponds and a …

Davis Creek Dredge Channel Data Report, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Nicholas Dinapoli

Reports

Introduction Davis Creek is located in Mathews County, Virginia (Figure 1) and empties into Mobjack Bay, a small bay in the lower Chesapeake Bay. The creek has a narrow mouth that splits into three prongs (Figure 2). The eastern prong is shortest at 2,200 ft from the mouth, and the western prong is the longest extending about 3,000 ft from the mouth. The Marina on Davis Creek occurs on this prong. Land use adjacent to the creek is mostly residential with some agriculture and wooded properties. The headwaters do not have extensive marsh. Instead the creek terminates soon after the …

Hole In The Wall Dredge Channel Data Report, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Nicholas J. Dinapoli

Reports

Hole in the Wall (HITW) is located in Mathews County, Virginia (Figure 1). It is a natural channel between fetch-limited barrier islands that provides access from Chesapeake Bay to Milford Haven and Gwynn Island. Milford Haven is a unique tidal creek watershed occurring between Chesapeake Bay and the Piankatank River and consists of numerous lateral tidal creeks entering from Gwynn Island to the north and others entering from the south including Lanes Creek, Stutts Creek, Billups Creek, Stoakes Creek and Whites Creek (Figure 2). Presently, the barrier between Milford Haven and Chesapeake Bay includes the northern barrier and Rigby Island. …

Timberneck Creek Dredge Channel Data Report, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Nicholas J. Dinapoli

Reports

Introduction Timberneck Creek is located in Gloucester County, Virginia (Figure 1). It is a long, but narrow creek that empties into the York River. The mouth is a wide embayment, but farther north, the creek narrows to about 400 ft wide and extends for about 2 miles to its marshy headwaters. The interior of the creek is irregular with many very small lateral creeks/marsh drainages emptying into the Timberneck. Timberneck Creek has never been dredged and a federally-defined channel does not exist at the site. As a new dredging project, the channel design must balance safety, economic, and sustainability requirements. …

A Modeling Study On The Influence Of Sea-Level Rise And Channel Deepening On Estuarine Circulation And Dissolved Oxygen Levels In The Tidal James River, Virginia, Usa, Ya Wang, Jian Shen

VIMS Articles

The impact of channel deepening and sea-level rise on the environmental integrity of an estuary is investigated using a three-dimensional hydrodynamic-eutrophication model. The model results show that dissolved oxygen (DO) only experienced minor changes, even when the deep channel was deepened by 3 m in the mesohaline and polyhaline regions of the James River. We found that vertical stratification decreased DO aeration while the estuarine gravitational circulation increased bottom DO exchange. The interactions between these two processes play an important role in modulating DO. The minor change in DO due to channel deepening indicates that the James River is unique …

The Importance Of Organic Content To Fractal Floc Properties In Estuarine Surface Waters, Insights From Video, Lisst, And Pump Sampling: Supporting Data, Kelsey A. Fall, Grace M. Massey, Carl T. Friedrichs

Data

The linked folders and associated data files contain the observations utilized in Fall, K.A., Friedrichs, C.T., Massey, G.M., Bowers, D.G., and Smith, S.J. (2021). The importance of organic content to fractal floc properties in estuarine surface waters: Insights from video, LISST, and pump sampling. JGR Oceans.

The file “Description of Data Files.pdf” outlines the content of the ten data folders, each of which is associated with a data set collected on an individual one-day cruise in the York River estuary.

A Database Of Ocean Primary Productivity From The 14c Method, J. F. Marra, R. T. Barber, (...), Walker O. Smith Jr., L. Zoffli

VIMS Articles

The database on ocean primary productivity comprises over two decades (1985–2008) of data that the authors have participated in collecting, using the assimilation of inorganic ¹⁴C through photosynthesis, in incubations carried out in situ. The dataset is perhaps unique in that it uses, overwhelmingly, consistent methodology while covering a wide geographic range. Ancillary data are included. Using the database, it is hoped that investigators can test for the relationships among the environmental drivers for ocean productivity, the meaning of the ¹⁴C method in terms of phytoplankton physiology and the dynamics in the water column, and as a resource …

Ocean_Data_Tools: A Matlab Toolbox For Interacting With Bulk Freely-Available Oceanographic Data, Laur Ferris

VIMS Articles

ocean_data_tools simplifies the process of extracting, formatting, and visualizing freely-available oceanographic data. A wealth of oceanographic data (from research cruises, autonomous floats, global ocean models, etc.) is accessible online. However, many oceanographers and environmental scientists (particularly those from subdisciplines not accustomed to working with large datasets) can be dissuaded from utilizing this data because of the overhead associated with determining how to batch download data and format it into easily-manipulable data structures. ocean_data_tools solves this problem by allowing the user to transform common oceanographic data sources into uniform structure arrays, call general functions on these structure arrays, perform custom calculations, …

Climate-Induced Variability In South Atlantic Wave Direction Over The Past Three Millennia, A. P. Silva, A. H. F. Klein, A. F. H. Fetter-Filho, Christopher J. Hein, Et Al

VIMS Articles

Through alteration of wave-generating atmospheric systems, global climate changes play a fundamental role in regional wave climate. However, long-term wave-climate cycles and their associated forcing mechanisms remain poorly constrained, in part due to a relative dearth of highly resolved archives. Here we use the morphology of former shorelines preserved in beach-foredune ridges (BFR) within a protected embayment to reconstruct changes in predominant wave directions in the Subtropical South Atlantic during the last ~ 3000 years. These analyses reveal multi-centennial cycles of oscillation in predominant wave direction in accordance with stronger (weaker) South Atlantic mid- to high-latitudes mean sea-level pressure gradient …

How Old Are Marshes On The East Coast, Usa? Complex Patterns In Wetland Age Within And Among Regions, Anna E. Braswell, James B. Heffernan, Matthew L. Kirwan

VIMS Articles

Sea‐level dynamics, sediment availability, and marine energy are critical drivers of coastal wetland formation and persistence, but their roles as continental‐scale drivers remain unknown. We evaluated the timing and spatial variability of wetland formation from new and existing cores collected along the Atlantic and Gulf coasts of the United States. Most basal peat ages occurred after sea‐level rise slowed (after ~4,000 years before present), but predominance of sea‐level rise studies may skew age estimates toward older sites. Near‐coastal sites tended to be younger, indicating creation of wetlands through basin infilling and overwash events. Age distributions differed among regions, with younger …

Restoration Of Seagrass Habitat Leads To Rapid Recovery Of Coastal Ecosystem Services, Robert J. Orth, Jonathan S. Lefcheck, Karen S. Mcglathery, Lillian Aoki, Mark Luckenbach, Kenneth A. Moore, Matthew P.J. Oreska, Richard A. Snyder, David J. Wilcox, Bo Lusk

VIMS Articles

There have been increasing attempts to reverse habitat degradation through active restoration, but few largescale successes are reported to guide these efforts. Here, we report outcomes from a unique and very successful seagrass restoration project: Since 1999, over 70 million seeds of a marine angiosperm, eelgrass (Zostera marina), have been broadcast into mid-western Atlantic coastal lagoons, leading to recovery of 3612 ha of seagrass. Well-developed meadows now foster productive and diverse animal communities, sequester substantial stocks of carbon and nitrogen, and have prompted a parallel restoration for bay scallops (Argopecten irradians). Restored ecosystem services are approaching historic levels, but we …

Effects Of Seawater Exchange On Water Chemistry Among Coastal Lakes With Intermittent Connections To The Sea, A. Challen Hyman, Dana Bigham Stephens

VIMS Articles

Intermittently closed and open lakes and lagoons (ICOLLs) are a dynamic class of coastal waterbodies with the unique feature of intermittently connecting to the sea. Understanding the functioning and potential threats of these globally rare systems is important to their preservation and protection. Coastal dune lakes of northwest Florida are one example of an understudied group of ICOLLs which connect with the Gulf of Mexico for brief periods of time. Using a 17-year, monthly water chemistry dataset, we analyzed long-term patterns in water chemistry among 16 coastal dune lakes. Using salinity as a proxy for frequency of seawater inflows, principal …

Volkilau: Volcano Rapid Response Balloon Campaign During The 2018 Kilauea Eruption, Jean Paul Vernier, Lars E. Kalnajs, Jorge Andrés Diaz, Tom Reese, Ernesto Corrales, Alfredo Alan, Hazel Vernier, Et Al

VIMS Articles

After nearly 35 years of stable activity, the Kilauea volcanic system in Hawaii went through sudden changes in May 2018 with the emergence of 20 volcanic fissures along the Lower Eastern Rift Zone (LERZ), destroying 700 homes in Leilani Estates and forcing more than 2,000 people to evacuate. Elevated volcanic emissions lasted for several months between May and September 2018, leading to low visibility and poor air quality in Hawaii and across the western Pacific. The NASA-funded VolKilau mission was rapidly mounted and conducted between 11 and 18 June 2018 to (i) profile volcanic emissions with SO2 and aerosol measurements, …

A Continental Shelf Pump For Co2 On The Adélie Land Coast, East Antarctica, Mar C. Arroyo, Elizabeth H. Shadwick, Stephen R. Rintoul, Kazuya Kusahara

VIMS Articles

We quantify the transport of inorganic carbon from the continental shelf to the deep ocean in Dense Shelf Water (DSW) from the Mertz and Ninnis Polynyas along the Adélie Land coast in East Antarctica. For this purpose, observations of total dissolved inorganic carbon (TCO₂) from two summer hydrographic surveys in 2015 and 2017 were paired with DSW volume transport estimates derived from a coupled ocean‐sea ice‐ice shelf model to examine the fate of inorganic carbon in DSW from Adélie Land. Transports indicate a net outflow of 227 ± 115 Tg C yr⁻¹ with DSW in the postglacial …

Estuarine Forecasts At Daily Weather To Subseasonal Time Scales, Andrew C. Ross, Charles A. Stock, Keith W. Dixon, Marjorie A.M. Friedrichs, Et Al

VIMS Articles

Most present forecast systems for estuaries predict conditions for only a few days into the future. However, there are many reasons to expect that skillful estuarine forecasts are possible for longer time periods, including increasingly skillful extended atmospheric forecasts, the potential for lasting impacts of atmospheric forcing on estuarine conditions, and the predictability of tidal cycles. In this study, we test whether skillful estuarine forecasts are possible for up to 35 days into the future by combining an estuarine model of Chesapeake Bay with 35-day atmospheric forecasts from an operational weather model. When compared with both a hindcast simulation from …

Trace Metal Availability Affects Greenhouse Gas Emissions And Microbial Functional Group Abundance In Freshwater Wetland Sediments, George Giannopoulos, Katherine R. Hartop, Bonnie L. Brown, Bongkeun Song, Lars Elsgaard, Rima B. Franklin

VIMS Articles

We investigated the effects of trace metal additions on microbial nitrogen (N) and carbon (C) cycling using freshwater wetland sediment microcosms amended with micromolar concentrations of copper (Cu), molybdenum (Mo), iron (Fe), and all combinations thereof. In addition to monitoring inorganic N transformations (NO₃^–, NO₂^–, N₂O, NH₄⁺) and carbon mineralization (CO₂, CH₄), we tracked changes in functional gene abundance associated with denitrification (nirS, nirK, nosZ), dissimilatory nitrate reduction to ammonium (DNRA; nrfA), and methanogenesis (mcrA). With regards to …

Coastal Marsh Degradation Into Ponds Induces Irreversible Elevation Loss Relative To Sea Level In A Microtidal System, Lennert Schepers, Patrick Brennand, Matthew L. Kirwan, Glenn Guntenspergen, Stijn Temmerman

VIMS Articles

Coastal marshes and their valuable ecosystem services are feared to be lost by sea level rise, yet the mechanisms of marsh degradation into ponds and potential recovery are poorly understood. We quantified and analyzed elevations of marsh surfaces and pond bottoms along a marsh loss gradient (Blackwater River, Maryland, USA). Our analyses show that ponds deepen with increasing tidal channel width connecting the ponds to the river, indicating a new feedback mechanism where channels lead to enhanced tidal export of pond bottom material. Pond elevations also decrease with increasing pond size, consistent with previous work identifying a positive feedback between …

Modeling Marsh‐Forest Boundary Transgression In Response To Storms And Sea‐Level Rise, J. Carr, G. Guntenspergen, Matthew L. Kirwan

VIMS Articles

The lateral extent and vertical stability of salt marshes experiencing rising sea levels depend on interacting drivers and feedbacks with potential for nonlinear behaviors. A two‐dimensional transect model was developed to examine changes in marsh and upland forest lateral extent and to explore controls on marsh inland transgression. Model behavior demonstrates limited and abrupt forest retreat with long‐term upland boundary migration rates controlled by slope, sea‐level rise (SLR), high water events, and biotic‐abiotic interactions. For low to moderate upland slopes the landward marsh edge is controlled by the interaction of these inundation events and forest recovery resulting in punctuated transgressive …

What Drives Property Owners To Modify Their Shorelines? A Case Study Of Gloucester County, Virginia, Sarah Stafford, Amanda Guthrie

VIMS Articles

This analysis uses data from a survey of shoreline property owners combined with data on shoreline modification permits to examine whether and how property owners modify their estuarine shorelines. We find that shoreline armoring is very popular among property owners that choose to modify their shoreline. While living shorelines are less common, applications for them are increasing both in absolute numbers and as a percentage of all shoreline modification requests. A number of different issues factor into the shoreline modification decision including effectiveness, cost, aesthetics, and property values. More valuable parcels are more likely to be modified, as are parcels …

Allostery In Oligomeric Receptor Models, Gregory D. Conradi Smith

Arts & Sciences Articles

We show how equilibrium binding curves of receptor homodimers can be expressed as rational polynomial functions of the equilibrium binding curves of the constituent monomers, without approximation and without assuming independence of receptor monomers. Using a distinguished spanning tree construction for reduced graph powers, the method properly accounts for thermodynamic constraints and allosteric interactions between receptor monomers (i.e. conformational coupling). The method is completely general; it begins with an arbitrary undirected graph representing the topology of a monomer state-transition diagram and ends with an algebraic expression for the equilibrium binding curve of a receptor oligomer composed of two or more …

2020 Chesapeake Bay Dead Zone Report, Virginia Institute Of Marine Science, Anchor Qea

Reports

The “Dead Zone” of the Chesapeake Bay refers to a volume of bottom water that is characterized by dissolved oxygen concentrations less than 2 mg/L, which is too low for aquatic organisms such as fish and blue crabs to thrive.The Chesapeake Bay experiences such “hypoxic”conditions every year, with the severity varying from year to year, depending on nutrient and freshwater inputs, wind, and temperature. Multiple metrics are used to relate the severity of hypoxia between different years:

• Hypoxic Duration (days): The number of days in a given year between the first and last day of hypoxic conditions exceeding 2 km3in …

Precision Measurement Of The Beam-Normal Single-Spin Asymmetry In Forward-Angle Elastic Electron-Proton Scattering, D. Androic, David S. Armstrong, Et Al.

Arts & Sciences Articles

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of theta_lab = 7.9 degrees and a mean energy of 1.149 GeV. The asymmetry result is B_n = -5.194 +- 0.067 (stat) +- 0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles …

A Machine‐Learning‐Based Model For Water Quality In Coastal Waters, Taking Dissolved Oxygen And Hypoxia In Chesapeake Bay As An Example, Xin Yu, Jian Shen, Jiabi Du

VIMS Articles

Hypoxia is a big concern in coastal waters as it affects ecosystem health, fishery yield, and marine water resources. Accurately modeling coastal hypoxia is still very challenging even with the most advanced numerical models. A data‐driven model for coastal water quality is proposed in this study and is applied to predict the temporal‐spatial variations of dissolved oxygen (DO) and hypoxic condition in Chesapeake Bay, the largest estuary in the United States with mean summer hypoxic zone extending about 150 km along its main axis. The proposed model has three major components including empirical orthogonal functions analysis, automatic selection of forcing …

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 …

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 …

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 …