Physical Sciences and Mathematics Commons^™

Multidisciplinary Observing In The World Ocean's Oxygen Minimum Zone Regions: From Climate To Fish - The Voice Initiative, V Garcon, J Karstensen, A Palacz, Et Al, Kevin C. Weng

VIMS Articles

Multidisciplinary ocean observing activities provide critical ocean information to satisfy ever-changing socioeconomic needs and require coordinated implementation. The upper oxycline (transition between high and low oxygen waters) is fundamentally important for the ecosystem structure and can be a useful proxy for multiple observing objectives connected to eastern boundary systems (EBSs) that neighbor oxygen minimum zones (OMZs). The variability of the oxycline and its impact on the ecosystem (VOICE) initiative demonstrates how societal benefits drive the need for integration and optimization of biological, biogeochemical, and physical components of regional ocean observing related to EBS. In liaison with the Global Ocean Oxygen …

Defining Boat Wake Impacts On Shoreline Stability Toward Management And Policy Solutions, Donna M. Bilkovic, Molly Mitchell, Jennifer Davis, Julie Herman, Elizabeth Andrews, Angela King, Pamela Mason, Navid Tahvildari, Jana Davis, Rachel L. Dixon

VIMS Articles

Coastal economies are often supported by activities that rely on commercial or recreational vessels to move people or goods, such as shipping, transportation, cruising, and fishing. Unintentionally, frequent or intense vessel traffic can contribute to erosion of coastlines; this can be particularly evident in sheltered systems where shoreline erosion should be minimal in the absence of boat waves. We reviewed the state of the science of known effects of boat waves on shoreline stability, examined data on erosion, turbidity, and shoreline armoring patterns for evidence of a response to boat waves in Chesapeake Bay, and reviewed existing management and policy …

A Conservation Palaeobiological Perspective On Chesapeake Bay Oysters, Rowan Lockwood, Roger L. Mann

VIMS Articles

The eastern oyster plays a vital role in estuarine habitats, acting as an ecosystem engineer and improving water quality. Populations of Chesapeake Bay oysters have declined precipitously in recent decades. The fossil record, which preserves 500 000 years of once-thriving reefs, provides a unique opportunity to study pristine reefs to establish a possible baseline for mitigation. For this study, over 900 fossil oysters were examined from three Pleistocene localities in the Chesapeake region. Data on oyster shell lengths, lifespans and population density were assessed. Comparisons to modern Crassostrea virginica, sampled from monitoring surveys of similar environments, reveal that fossil oysters …

Long-Term Annual Aerial Surveys Of Submersed Aquatic Vegetation (Sav) Support Science, Management, And Restoration, Robert J. Orth, William C. Dennison, Cassie Gurbisz, Michael Hannam, Jeni Keisman, J. Brooke Landry, Jonathan S. Lefcheck, Kenneth A. Moore, Rebecca R. Murphy, Christopher J. Patrick, Jeremy Testa, Donald E. Weller, David J. Wilcox, Richard A. Batiuk

VIMS Articles

Aerial surveys of coastal habitats can uniquely inform the science and management of shallow, coastal zones, and when repeated annually, they reveal changes that are otherwise difficult to assess from ground-based surveys. This paper reviews the utility of a long-term (1984–present) annual aerial monitoring program for submersed aquatic vegetation (SAV) in Chesapeake Bay, its tidal tributaries, and nearby Atlantic coastal bays, USA. We present a series of applications that highlight the program’s importance in assessing anthropogenic impacts, gauging water quality status and trends, establishing and evaluating restoration goals, and understanding the impact of commercial fishing practices on benthic habitats. These …

Tidal Erosion And Upstream Sediment Trapping Modulate Records Of Land-Use Change In A Formerly Glaciated New England Estuary, Justin L. Shawler, Christopher J. Hein, Elizabeth A. Canuel, Et Al

VIMS Articles

Land clearing, river impoundments, and other human modifications to theupland landscape and within estuarine systems can drive coastal change at local to regionalscales. However, as compared with mid-latitude coasts, the impacts of human modificationsalong sediment-starved formerly glaciated coastal landscapes are relatively understudied.To address this gap, we present a late-Holocene record of changing sediment accumulationrates and sediment sources from sediment cores collected across a tidal flat in theMerrimack River estuary (Mass., USA). We pairsedimentology, geochronology, bulk- andstable-isotope organic geochemistry, and hydrodynamic simulations with historical datato evaluate human and natural impacts on coastal sediment fluxes. During the 17th to19th centuries, accumulation rates …

Living Shoreline Sea Level Resiliency: Performance And Adaptive Management Of Existing Breakwater Sites, Year 2 Summary Report, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Angela C. Milligan

Reports

The Coastal Zone Management program, through NOAA grants, has funded several projects that have reviewed design considerations and monitored living shoreline systems for effectiveness at both shore protection and habitat enhancement. These studies presented data regarding the construction and performance of three living shoreline projects that were built between 1999 and 2003 in Maryland (Hardaway et al., 2007 and 2009) and were in part the basis for the “Living Shoreline Design Guidelines for Shore Protection in Virginia’s Estuarine Environments” and the contractor training classes (Hardaway et al., 2017). In addition, extensive research has been done on the design and performance …

2019 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:

• Maximum Daily Hypoxic Volume (km3): The maximum volume of Chesapeake Bay water experiencing hypoxic conditions on any given day

• Average Summer Hypoxic …

Spatial Multiplexing Of Squeezed Light By Coherence Diffusion, Jian Sun, (...), Eugeniy E. Mikhailov, Irina Novikova, Et Al.

Arts & Sciences Articles

Spatially splitting nonclassical light beams is in principle prohibited due to noise contamination during beam splitting. We propose a platform based on thermal motion of atoms to realize spatial multiplexing of squeezed light. Light channels of separate spatial modes in an antirelaxation coated vapor cell share the same long-lived atomic coherence jointly created by all channels through the coherent diffusion of atoms, which in turn enhances the individual channel’s nonlinear process responsible for light squeezing. Consequently, it behaves as squeezed light in one optical channel transferring to other distant channels even with laser powers below the threshold for squeezed light …

The Importance Of Antarctic Krill In Biogeochemical Cycles, El Cavan, A Belcher, Sl Hill, S Kawaguchi, S Mccormack, B Meyer, S Nicol, K Schmidt, Deborah K. Steinberg, Ga Tarling, Pw Boyd

VIMS Articles

Antarctic krill (Euphausia superba) are swarming, oceanic crustaceans, up to two inches long, and best known as prey for whales and penguins – but they have another important role. With their large size, high biomass and daily vertical migrations they transport and transform essential nutrients, stimulate primary productivity and influence the carbon sink. Antarctic krill are also fished by the Southern Ocean’s largest fishery. Yet how krill fishing impacts nutrient fertilisation and the carbon sink in the Southern Ocean is poorly understood. Our synthesis shows fishery management should consider the influential biogeochemical role of both adult and larval …

Asynchronous Nitrogen Supply And Demand Produce Nonlinear Plant Allocation Responses To Warming And Elevated Co2, Genevieve L. Noyce, Matthew L. Kirwan, Roy L. Rich, J. Patrick Megonigal

VIMS Articles

Terrestrial ecosystem responses to climate change are mediated by complex plant–soil feedbacks that are poorly understood, but often driven by the balance of nutrient supply and demand. We actively increased aboveground plant-surface temperature, belowground soil temperature, and atmospheric CO₂ in a brackish marsh and found nonlinear and nonadditive feedbacks in plant responses. Changes in root-to-shoot allocation by sedges were nonlinear, with peak belowground allocation occurring at +1.7 °C in both years. Above 1.7 °C, allocation to root versus shoot production decreased with increasing warming such that there were no differences in root biomass between ambient and +5.1 °C plots …

Impacts Of Sea Level Rise On Hypoxia In The Chesapeake Bay: A Model Intercomparison, Pierre St-Laurent, Marjorie A.M. Friedrichs, Ming Li, Wenfei Ni

Reports

Over recent years a number of studies have examined the effects of sea level rise (SLR) on hypoxia in Chesapeake Bay. However, variations in the methodology, the years considered, and the metrics reported made comparisons between these studies difficult. To clarify the effects of SLR on the Bay’s hypoxia, we present an intercomparison between four numerical models following a common methodology. The models share the riverine fluxes, baseline period (1991–1995), and consider the same three scenarios of SLR: an increase in sea level of 0.17m, 0.50m, and 1.00m (representative of years 2025, 2050 and 2100, respectively). SLR is the sole …

Organophosphate And Novel Brominated Flame Retardants Exposure In Childbearing Women Via House Dust, Z. Percy, Mark J. La Guardia, Y. Xu, Robert Hale, B. Lanphear

VIMS Articles

No abstract provided.

James River Water Quality Model Refinement And Scenario Simulations, Jian Shen, Qubin Qin

Reports

This project was part of the Virginia Department of Environmental Quality’s (DEQ) study to evaluate the protectiveness of chlorophyll criteria and consider potential criteria revisions, along with implications for the James River portion of the Chesapeake Bay TMDL.

Scientific Considerations For Acidification Monitoring In The Us Mid-Atlantic Region, Ka Goldsmith, S Lau, Et Al, Eh Shadwick, Et Al

VIMS Articles

Coastal and ocean acidification has the potential to cause significant environmental and societal impacts. Monitoring carbonate chemistry parameters over spatial and temporal scales is challenging, especially with limited resources. A lack of monitoring data can lead to a limited understanding of real-world conditions. Without such data, robust experimental and model design is challenging, and the identification and understanding of episodic acidification events is nearly impossible. We present considerations for resource managers, academia, and industry professionals who are currently developing acidification monitoring programs in the Mid-Atlantic region. We highlight the following considerations for deliberation: 1) leverage existing infrastructure to include multiple …

The Floodwater Depth Estimation Tool (Fwdet V2.0) For Improved Remote Sensing Analysis Of Coastal Flooding, S Cohen, A Raney, D Munasinghe, Jon Derek Loftis, Et Al

VIMS Articles

Remote sensing analysis is routinely used to map flooding extent either retrospectively or in near-real time. For flood emergency response, remote-sensing-based flood mapping is highly valuable as it can offer continued observational information about the flood extent over large geographical domains. Information about the floodwater depth across the inundated domain is important for damage assessment, rescue, and prioritizing of relief resource allocation, but cannot be readily estimated from remote sensing analysis. The Floodwater Depth Estimation Tool (FwDET) was developed to augment remote sensing analysis by calculating water depth based solely on an inundation map with an associated digital elevation model …

Tidal Variation In Cohesive Sediment Distribution And Sensitivity To Flocculation And Bed Consolidation In An Idealized, Partially Mixed Estuary, Danielle R.N. Tarpley, Courtney K. Harris, Carl Friedrichs, Christopher T. Sherwood

VIMS Articles

Particle settling velocity and erodibility are key factors that govern the transport of sediment through coastal environments including estuaries. These are difficult to parameterize in models that represent mud, whose properties can change in response to many factors, including tidally varying suspended sediment concentration (SSC) and shear stress. Using the COAWST (Coupled Ocean-Atmosphere-Wave-Sediment Transport) model framework, we implemented bed consolidation, sediment-induced stratification, and flocculation formulations within an idealized two-dimensional domain that represented the longitudinal dimension of a micro-tidal, muddy, partially mixed estuary. Within the Estuarine Turbidity Maximum (ETM), SSC and median floc diameter varied by a factor of four over …

Global Change Effects On Plant Communities Are Magnified By Time And The Number Of Global Change Factors Imposed, Kj Komatsu, Ml Avolio, Et Al, David S. Johnson, Et Al

VIMS Articles

Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (< 10 y). In contrast, long-term (>= 10 y) experiments show increasing community divergence of …

Rural Shallow Water Dredging: Channel Assessment And Disposal Site Strategies, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox

Reports

The goal of this report is to provide general considerations for localities on the dredging and disposal of material from shallow draft channels, in particular for those channels on the Middle Peninsula, Northern Neck, and Eastern Shore of Virginia (Figure 1-1). This report offers background on shallow draft channels, both federally and non-federally maintained, suggests procedures for the dredging and disposal process, and applies the process to an existing channel. Existing data on the Middle Peninsula, Northern Neck, and Eastern Shore channels are provided to assist localities with management decisions. In addition to data for most of the existing federal …

Pamunkey Indian Reservation Shoreline Management Plan, Donna A. Milligan, C. Scott Hardaway Jr., Christine A. Wilcox

Reports

In 2015, the federal government officially recognized the Pamunkey Indian tribe. The tribe has a reservation located on the Pamunkey River in King William County (Figure 1-1) and is one of the nation's oldest, dating back to 1646 (Encyclopedia Virginia, 2015). The Reservation has about 13 miles of shoreline encompassing about 1,100 acres. According to the National Wetlands Inventory (US Fish and Wildlife Service, 2016), the Reservation has about 80 acres of freshwater emergent wetland and 530 acres of freshwater forested/shrub wetland. Approximately 90 people live on the Reservation and up to 600 people visit in a year.

The goal …

Virginia Stormwater Act, Tiered Approach For Rural Tidewater Localities: Generation Of Watershed Impervious Maps, Christine Tombleson

Reports

An amendment to Virginia's Stormwater Management Act was adopted to implement a tiered approach to stormwater management for rural Tidewater localities. To participate a locality is required to have a map showing the boundaries of the locality, with each watershed located partially or wholly within the locality, and the percentage of impervious cover (cover that impedes the natural infiltration of water into the soil) within each watershed. Center staff created maps indicating the initial percent of existing impervious cover present in each watershed for the Middle Peninsula Planning District (MPPDC) localities; Gloucester, Essex, King and Queen, King William, Mathews, Middlesex …

Preliminary Assessment Of Benthic Macrofauna Community Within Intertidal Mudflats, Lake Rudee, Virginia Beach, Virginia, M. Lisa Kellogg

Reports

The goal of this assessment was to evaluate the proposed dredging site at Lake Rudee to determine whether the natural resources within the proposed dredge area were of sufficient value that the permitting agency might require further data to be collected to aid in determining whether to grant a dredging permit or how much mitigation to require.

It’S About Time: A Synthesis Of Changing Phenology In The Gulf Of Maine Ecosystem, Md Staudinger, Ke Mills, Et Al, David S. Johnson, Et Al

VIMS Articles

The timing of recurring biological and seasonal environmental events is changing on a global scale relative to temperature and other climate drivers. This study considers the Gulf of Maine ecosystem, a region of high social and ecological importance in the Northwest Atlantic Ocean and synthesizes current knowledge of (a) key seasonal processes, patterns, and events; (b) direct evidence for shifts in timing; (c) implications of phenological responses for linked ecological-human systems; and (d) potential phenology-focused adaptation strategies and actions. Twenty studies demonstrated shifts in timing of regional marine organisms and seasonal environmental events. The most common response was earlier timing, …

Validating An Operational Flood Forecast Model Using Citizen Science In Hampton Roads, Va, Usa, Jon Derek Loftis, Molly Mitchell, Daniel Schatt, David R. Forrest, Harry V. Wang, David Mayfield, William A. Stiles

VIMS Articles

Changes in the eustatic sea level have enhanced the impact of inundation events in the coastal zone, ranging in significance from tropical storm surges to pervasive nuisance flooding events. The increased frequency of these inundation events has stimulated the production of interactive web-map tracking tools to cope with changes in our changing coastal environment. Tidewatch Maps, developed by the Virginia Institute of Marine Science (VIMS), is an effective example of an emerging street-level inundation mapping tool. Leveraging the Semi-implicit Cross-scale Hydro-science Integrated System Model (SCHISM) as the engine, Tidewatch operationally disseminates 36-h inundation forecast maps with a 12-h update frequency. …

A Hydrodynamic Model For Galveston Bay And The Shelf In The Northern Gulf Of Mexico, Jiabi Du, Kyeong Park, Jian Shen, Yinglong J. Zhang, Xin Yu, Fei Ye, Zhengui Wang, Nancy N. Rabalais

VIMS Articles

A 3-D unstructured-grid hydrodynamic model for the northern Gulf of Mexico was developed, with a hybrid s–z vertical grid and high-resolution horizontal grid for the main estuarine systems along the Texas–Louisiana coast. This model, based on the Semi-implicit Cross-scale Hydroscience Integrated System Model (SCHISM), is driven by the observed river discharge, reanalysis atmospheric forcing, and open boundary conditions from global HYCOM output. The model reproduces the temporal and spatial variation of observed water level, salinity, temperature, and current velocity in Galveston Bay and on the shelf. The validated model was applied to examine the remote influence of neighboring …

Collaborative Science To Enhance Coastal Resilience And Adaptation, C. Reid Nichols, Lynn Wright, Arthur Cosby, Alain Henaff, Jon Derek Loftis, Et Al

VIMS Articles

Impacts from natural and anthropogenic coastal hazards are substantial and increasing significantly with climate change. Coasts and coastal communities are increasingly at risk. In addition to short-term events, long-term changes, including rising sea levels, increasing storm intensity, and consequent severe compound flooding events are degrading coastal ecosystems and threatening coastal dwellers. Consequently, people living near the coast require environmental intelligence in the form of reliable short-term and long-term predictions in order to anticipate, prepare for, adapt to, resist, and recover from hazards. Risk-informed decision making is crucial, but for the resulting information to be actionable, it must be effectively and …

Toward A Coordinated Global Observing System For Seagrasses And Marine Macroalgae, J. Emmett Duffy, L. Benedetti-Cecchi, Et Al, Robert J. Orth, Et Al

VIMS Articles

In coastal waters around the world, the dominant primary producers are benthic macrophytes, including seagrasses and macroalgae, that provide habitat structure and food for diverse and abundant biological communities and drive ecosystem processes. Seagrass meadows and macroalgal forests play key roles for coastal societies, contributing to fishery yields, storm protection, biogeochemical cycling and storage, and important cultural values. These socio-economically valuable services are threatened worldwide by human activities, with substantial areas of seagrass and macroalgal forests lost over the last half-century. Tracking the status and trends in marine macrophyte cover and quality is an emerging priority for ocean and coastal …

Mechanisms Involving Sensory Pathway Steps Inform Impacts Of Global Climate Change On Ecological Processes, Emily B. Rivest, Brittany Jellison, Gabriel Ng, Et Al

VIMS Articles

Human-caused environmental change will have significant non-lethal and indirect impacts on organisms due to altered sensory pathways, with consequences for ecological interactions. While a growing body of work addresses how global ocean change can impair the way organisms obtain and use information to direct their behavior, these efforts have typically focused on one step of the pathway (e.g., reception of a cue/signal), one sensory modality (e.g., visual), or one environmental factor (e.g., temperature). An integrated view of how aspects of environmental change will impact multiple sensory pathways and related ecological processes is needed to better anticipate broader consequences for marine …

Assessment Of Spray Polyurethane Foam Worker Exposure To Organophosphate Flame Retardants Through Measures In Air, Hand Wipes, And Urine, Cf Estill, J Slone, Et Al, Mark J. La Guardia, Et Al

VIMS Articles

Tris(1-chloro-2-propyl) phosphate (TCPP, also referenced as TCIPP), a flame retardant used in spray polyurethane foam insulation, increases cell toxicity and affects fetal development. Spray polyurethane foam workers have the potential to be exposed to TCPP during application. In this study, we determined exposure to TCPP and concentrations of the urinary biomarker bis(1-chloro-2-propyl) phosphate (BCPP) among 29 spray polyurethane foam workers over 2 work days. Work was conducted at residential or commercial facilities using both open-cell (low density) and closed-cell (high density) foam. Study participants provided two personal air samples (Day 1 and Day 2), two hand wipe samples (Pre-shift Day …

Seasonal And Spatial Variation In The Location And Reactivity Of A Nitrate‐Contaminated Groundwater Discharge Zone In A Lakebed, Rl Smith, Da Repert, Dl Stoliker, Db Kent, Bk Song, Et Al

VIMS Articles

Groundwater discharge delivering anthropogenic N from surrounding watersheds can impact lake nutrient budgets. However, upgradient groundwater processes and changing dynamics in N biogeochemistry at the groundwater‐lake interface are complex. In this study, seasonal water‐level variations in a groundwater flow‐through lake altered discharge patterns of a wastewater‐derived groundwater contaminant plume, thereby affecting biogeochemical processes controlling N transport. Pore water collected 15 cm under the lakebed along transects perpendicular to shore varied from oxic to anoxic with increasing nitrate concentrations (10–75 μM) and corresponding gradients in nitrite and nitrous oxide. Pore water depth profiles of nitrate concentrations and stable isotopic compositions largely …

Second-Order Dirac Superconductors And Magnetic Field Induced Majorana Hinge Modes, Sayed Ali Akbar Ghorashi, Xiang Hu, Taylor L. Hughes, Enrico Rossi

Arts & Sciences Articles

We identify three-dimensional higher-order superconductors characterized by the coexistence of one-dimensional Majorana hinge states and gapless surface states. We show how such superconductors can be obtained starting from the model of a spinful quadrupolar semimetal with two orbitals and adding an s-wave superconducting pairing term. By considering all the possible s-wave pairings satisfying Fermi-Dirac statistics we obtain six different superconducting models. We find that for two of these models a flat band of hinge Majorana states coexist with surface states, and that these models have a nonvanishing quadrupolelike topological invariant. Two of the other models, in the presence of a …