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Assessment Of The High-Resolution Sediment Gravity Flow Record In Prince William Sound, Alaska, Elisabeth Rose Clyne

Dissertations, Theses, and Masters Projects

South-Central Alaska is one of the most seismically active and climatologically sensitive places in the world. Within this region, Prince William Sound (PWS) receives abundant sediment from multiple sources, potentially housing a high-resolution environmental record spanning the past 4,000 years. Inputs to PWS are derived from local rivers and glaciers, and may include earthquake- and glacial-outburst-triggered sediment gravity flows. Therefore, this is an ideal location to investigate the long-term record of seismic, glacial, and riverine activity. This study examines the elemental, grain size, and stable isotope signatures in PWS to identify gravity flow deposits and the potential paleoseismic and paleoclimate …

Soed Open Course: Seamless Modeling From Creek To Ocean On Unstructured Grids, Y. Joseph Zhang

Miscellaneous

This course explains the basic formulations used in the cross-scale SCHISM model, including the recent new developments. Hands-on tutorials will be conducted to familiarize the trainees with the basic tools useful for the modeling system. Although no formal pre-requisites are expected, trainees with prior UG model experience may find it easier to learn. Upon completion the trainees will have acquired basic knowledge on workflow in typical SCHISM simulations and be able to conduct simulations for cross-scale baroclinic processes as found in geophysical fluid dynamics (GFD)

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Numerical Simulations Of The Biogeochemical Impact Of Atmospheric Nitrogen Deposition On Surface Waters Of The Western North Atlantic, Pierre St-Laurent, Marjorie A.M. Friedrichs

Data

The impacts of atmospheric nitrogen deposition on the chlorophyll and nitrogen dynamics of surface waters in the western North Atlantic (25-45N, 65-80W) were examined with a biogeochemical ocean model forced with a regional atmospheric chemistry model. The model simulations cover the period 2004 to 2008 and are fully described in the following reference: St-Laurent, P., et al., Impacts of atmospheric nitrogen deposition on surface waters of the western North Atlantic mitigated by multiple feedbacks, J. Geophys. Res. Oceans, vol.122, doi:10.1002/2017jc013072.

Incorporating Sea Level Change Scenarios Into Norfolk Harbor Channels Deepening And Elizabeth River Southern Branch Navigation Improvements Study : Final Report On The “Hydrodynamic Modeling”, Zhuo Liu, Harry V. Wang, Yinglong J. Zhang, Fei Ye

Reports

The Virginia Institute of Marine Science (VIMS) team has applied a 3D unstructured-grid hydrodynamic model SCHISM in the study of the impact of channel dredging on hydrodynamics in the lower Chesapeake Bay project area. This report is a companion report to that of Zhang et al. (2017; doi:10.21220/V5MF0F) and focuses on the impact of channel dredging specifically under the projected future sea-level change (SLC) of 1 meter rise by 2100. This is an average of the high end of semi-empirical, global sea-level rise (SLR) projections adopted by the Virginia Port Authority (VPA) and the Army Corps of Engineers, Norfolk District, …

Assessment Of Hydrodynamic And Water Quality Impacts For Channel Deepening In The Thimble Shoals, Norfolk Harbor, And Elizabeth River Channels : Final Report On The “Hydrodynamic Modeling”, Yinglong J. Zhang, Harry V. Wang, Fei Ye, Zhengui Wang

Reports

For over twenty years, the U. S. Army Corps of Engineers (USACE) and the Virginia Port Authority (VPA), representing the Commonwealth Secretary of Transportation, have collaborated on projects key to port development that also preserve the environmental integrity of both Hampton Roads and the Elizabeth River. The USACE and the VPA are working to investigate channel deepening in this region to provide access to a new generation of cargo ships (e.g., Panamax-class). The main goal of this project is to investigate the feasibility for Norfolk Harbor channel deepening in the lower James and Elizabeth Rivers and assess the environmental impact …

Assessment Of Hydrodynamic And Water Quality Impacts For Channel Deepening In The Thimble Shoals, Norfolk Harbor, And Elizabeth River Channels, Jian Shen, Rico Wang, Mac Sisson

Reports

To investigate the feasibility for Norfolk Harbor channel deepening in the lower James and Elizabeth Rivers, one of the key services of the project is to evaluate the impacts of deepening the Atlantic Ocean Channel to 55 feet (from 50 feet), Thimble Shoal Channel to 55 feet (from 50 feet), Elizabeth River (north of Lambert Point) to 50 feet (from 45 feet) and the Southern Branch (north of the I64 Bridge) to 50/45/45 feet. In general, the shipping channel dredging will result in enhancement of estuarine gravitational circulation, accentuate the tidal and wind wave influence upstream, and affect the ecosystem …

Incorporation Of Sea Level Change Scenarios Into Norfolk Harbor And Channels Deepening Study & Elizabeth River Southern Branch Navigation Improvements Study : Final Report, Rico Wang, Jian Shen, Mac Sisson

Reports

Previously the VIMS modeling group has studied the impact of channel deepening on the water quality in lower James River, including Norfolk Harbor and Elizabeth River. A study of the response of the water quality to future Sea Level Change (SLC) is required by present USACE guidance (ER 1100-2-8162 and ETL 1100-2-1). ETL 1100-2-1 recommends analyzing the effects of SLC on the projects at three future time periods of post-construction, including 20 years, 50 years, and 100 years. The future change of sea level is mainly caused by the sea level rise (SLR) in this region. This document provides results …

Sea Level Rise May Increase Extinction Risk Of A Saltmarsh Ontogenetic Habitat Specialist, David S. Johnson, Bethany L. Williams

VIMS Articles

Specialist species are more vulnerable to environmental change than generalist species. For species with ontogenetic niche shifts, specialization may occur at a particular life stage making those stages more susceptible to environmental change. In the salt marshes in the northeast U.S., accelerated sea level rise is shifting vegetation patterns from flood-intolerant species such as Spartina patens to the flood-tolerant Spartina alterniflora. We tested the potential impact of this change on the coffee bean snail, Melampus bidentatus, a numerically dominant benthic invertebrate with an ontogenetic niche shift. From a survey of eight marshes throughout the northeast U.S., small snails …

A Test Bed For Coastal And Ocean Modeling, R. A. Luettich Jr., L. D. Wright, C. R. Nichols, R. Baltes, M. A.M. Friedrichs, Et Al

VIMS Articles

No abstract provided.

Adapt Virginia: A New Web Portal About Climate Change Adaptations (Www.Adaptva.Org), Center For Coastal Resources Management, Virginia Institute Of Marine Science

Reports

Rivers & Coast is a periodic publication of the Center for Coastal Resources Management, Virginia Institute of Marine Science. The goal of Rivers & Coast is to keep readers well informed of current scientific understanding behind key environmental issues related to watershed rivers and coastal ecosystems of the Chesapeake Bay.

A Model Archive For A Coupled Hydrodynamic-Sediment Transport-Biogeochemistry Model For The Rhône River Sub-Aqueous Delta, France, Julia Moriarty, Courtney K. Harris, Katja Fennel, Kehui Xu, Christophe Rabouille, Marjorie A.M. Friedrichs

Data

This dataset includes model input, code, and output used in the publication Moriarty et al. (2017, Biogeosciences), which used a coupled hydrodynamic-sediment transport-biogeochemical model to investigate the roles of resuspension, diffusion and biogeochemical processes on oxygen dynamics on the Rhône River sub-aqueous delta, France. Model development for this project focused on coupling the sediment transport and water-column biogeochemistry modules in the Regional Ocean Modeling System (ROMS) by incorporating a seabed biogeochemistry module into the ROMS framework. As described in Moriarty et al. (2017, Biogeosciences), the coupled model can account for diffusion of nutrients across the seabed-water-column interface; storage …

Climate Change Impacts On Southern Ross Sea Phytoplankton Composition, Productivity, And Export, Daniel E. Kaufman, Marjorie A. M. Friedrichs, Walker O. Smith Jr., Eileen E. Hofmann, Michael S. Dinniman, John C. P. Hemmings

VIMS Articles

The Ross Sea, a highly productive region of the Southern Ocean, is expected to experience warming during the next century along with reduced summer sea ice concentrations and shallower mixed layers. This study investigates how these climatic changes may alter phytoplankton assemblage composition, primary productivity, and export. Glider measurements are used to force a one-dimensional biogeochemical model, which includes diatoms and both solitary and colonial forms of Phaeocystis antarctica. Model performance is evaluated with glider observations, and experiments are conducted using projections of physical drivers for mid-21st and late-21st century. These scenarios reveal a 5% increase in primary productivity …

2016 Data Collected For Resistivity, Magnetic Susceptibility And Sediment Characterization Of The York River Estuary, Va In Support Of The Empirical Investigation Of The Factors Influencing Marine Applications Of Emi (Year 2 Of Serdp Project Mr-2409), Grace M. Massey, Carl T. Friedrichs

Data

The objective of this component of the Strategic Environmental Research and Development Program (SERDP) Project MR-2409 was to conduct field measurements to aid in the determination of the electromagnetic induction (EMI) response to the water column and underlying sediments in the York River estuary, which includes water column and sediment properties similar to many underwater environments of interest to unexploded ordinance detection. Data and samples from a standard suite of hydrographic and sedimentological measurements, as well as electrical resistivity and magnetic susceptibility, were collected and analyzed for each location. These cruises provided opportunities to obtain information that is being used …

Hampton Roads Crossing Study Supplemental Environmental Impact Statement: Evaluation Of Potential Impact On Surface Water Elevation, Flow, Salinity, And Bottom Shear Stress, Yinglong J. Zhang, Harry V. Wang, Zhuo Liu, Mac Sisson, Jian Shen

Reports

The purpose of this study is to evaluate the potential impacts of the proposed alternatives for the highway crossing in Hampton Roads on physical characteristics of surface water elevation, flow, salinity, and bottom shear stress. The analysis is part of the Virginia Department of Transportation (VDOT), the Federal Highway Administration, and other stakeholders’ Supplemental Environmental Impact Statement (SEIS) for Hampton Roads Crossing Study (HRCS).

2017 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

2017 Chesapeake Bay Bridge Tunnel Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

2017 Hampton Roads Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

2017 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

Temporal Progression Of Photosynthetic-Strategy In Phytoplankton In The Ross Sea, Antarctica, T. J. Ryan-Keogh, L. M. Delizo, Walker O. Smith Jr., Et Al

VIMS Articles

The bioavailability of iron influences the distribution, biomass and pioductivity of phytoplankton in the Ross Sea, one of the most productive regions in the Southern Ocean. We mapped the spatial and temporal extent and severity of iron-limitation of the native phytoplankton assemblage using long- (>24 h) and short-term (24 h) iron-addition experiments along with physiological and molecular characterisations during a cruise to the Ross Sea in December February 2012. Phytoplankton increased their photosynthetic efficiency in response to iron addition, suggesting proximal iron limitation throughout most of the Ross Sea during summer. Molecular and physiological data further indicate that as …

Impact Of Climate Variation And Human Adaptation On The Physical Transport Processes And Water Exchange In Chesapeake Bay, Jiabi Du

Dissertations, Theses, and Masters Projects

The efficiencies of water exchanges in both vertical and horizontal directions reflect the overall impact of various physical processes and serve as important indicators of physical control over a variety of ecological and biogeochemical processes. The vertical exchange between surface layers and bottom layers of a waterbody has proved to exert great control over the hypoxic condition, while the horizontal exchange between an estuary and coastal ocean determines the flushing capacity of the estuary and the retention rate of riverine materials. Various processes, such as tidal flushing, tidal mixing, gravitational circulation, and lateral circulation, can affect water exchange. Therefore, water …

Seasonal Nitrogen Uptake And Regeneration In The Western Coastal Arctic, Se Baer, Rachel E. Sipler, Qn Roberts, Pl Yager, Me Frischer, D Bronk

VIMS Articles

Here, we present the first study to investigate the seasonal importance of amino acid-nitrogen (N) to Arctic near shore microbial communities. We measured primary productivity and the uptake of ammonium, nitrate, urea, and amino acids in two size fractions (> 3 m and approximately 0.7-3 m), as well as ammonium regeneration and nitrification using N-15 and C-13 tracer approaches in the near-shore waters of the Chukchi Sea, during January, April, and August for two consecutive years. At discrete depths, nitrate comprised 46-78% of the total dissolved N pool during January and April but only 2-6% during August. Dissolved organic N …

Associated Dataset: Climate Change Impacts On Southern Ross Sea Phytoplankton Composition, Productivity And Export, Daniel E. Kaufman, Marjorie A.M. Friedrichs, Walker O. Smith Jr., Eileen E. Hofmann, Michael S. Dinniman, John C.P. Hemmings

Data

This dataset includes data used in the publication Kaufman et al., 2017, JGR-Oceans, which investigates how these climatic changes in the Ross Sea, Antarctica, may alter phytoplankton composition, primary productivity and export. A one-dimensional version of the Model of Ecosystem Dynamics, nutrient Utilisation, Sequestration and Acidification was adapted for use in the Ross Sea (MEDUSA-RS). Glider measurements were used to force MEDUSA-RS, which includes diatoms and both solitary and colonial forms of Phaeocystis antarctica. Model performance was evaluated with glider observations, and experiments were conducted using projections of physical drivers for mid- and late-21st century. Additional scenarios examined the …

Using Water Quality Models In Management - A Multiple Model Assessment, Analysis Of Confidence, And Evaluation Of Climate Change Impacts, Isaac Irby

Dissertations, Theses, and Masters Projects

Human impacts on the Chesapeake Bay through increased nutrient run-off as a result of land-use change, urbanization, and industrialization, have resulted in a degradation of water quality over the last half-century. These direct impacts, compounded with human-induced climate changes such as warming, rising sea-level, and changes in precipitation, have elevated the conversation surrounding the future of water quality in the Bay. The overall goal of this dissertation project is to use a combination of models and data to better understand and quantify the impact of changes in nutrient loads and climate on water quality in the Chesapeake Bay. This research …

The Role Of Seabed Resuspension On Oxygen And Nutrient Dynamics In Coastal Systems: A Numerical Modeling Study, Julia Miege Moriarty

Dissertations, Theses, and Masters Projects

Seabed resuspension can impact organic matter fate and water column biogeochemistry in coastal environments. Cycles of erosion and deposition can, for example, affect remineralization rates, seabed-water column fluxes of dissolved oxygen and nutrients, and light attenuation. Yet, models that incorporate both sediment transport and biogeochemical processes are rare, and nearly all neglect the effect of resuspension on oxygen and nutrient dynamics. Development of a novel tool, i.e. a coupled hydrodynamic-sediment transport-biogeochemical model, allowed for an investigation of the role of resuspension on oxygen and nitrogen dynamics within three distinct coastal environments. Called HydroBioSed, the coupled model was built within the …

Preliminary Estimate Of Contribution Of Arctic Nitrogen Fixation To The Global Nitrogen Budget, Rachel E. Sipler, Donglai Gong, Se Baer, Mp Sanderson, Qn Roberts, M Mulholland, Da Bronk

VIMS Articles

Dinitrogen (N-2) fixation is the source of all biologically available nitrogen on earth, and its presence or absence impacts net primary production and global biogeochemical cycles. Here, we report rates of 3.5-17.2 nmol N L-1 d(-1) in the ice-free coastal Alaskan Arctic to show that N-2 fixation in the Arctic Ocean may be an important source of nitrogen to a seasonally nitrogen-limited system. If widespread in surface waters over ice-free shelves throughout the Arctic, N-2 fixation could contribute up to 3.5 Tg N yr(-1) to the Arctic nitrogen budget. At these rates, N-2 fixation occurring in ice-free summer waters would …

Ocean Acidification Compromises A Planktic Calcifier With Implications For Global Carbon Cycling, Cv Davis, Emily B. Rivest, Et Al

VIMS Articles

Anthropogenically-forced changes in ocean chemistry at both the global and regional scale have the potential to negatively impact calcifying plankton, which play a key role in ecosystem functioning and marine carbon cycling. We cultured a globally important calcifying marine plankter (the foraminifer, Globigerina bulloides) under an ecologically relevant range of seawater pH (7.5 to 8.3 total scale). Multiple metrics of calcification and physiological performance varied with pH. At pH > 8.0, increased calcification occurred without a concomitant rise in respiration rates. However, as pH declined from 8.0 to 7.5, calcification and oxygen consumption both decreased, suggesting a reduced ability to precipitate …

Interactive Effects Of Elevated Temperature And Co2 On Nitrate, Urea, And Dissolved Inorganic Carbon Uptake By A Coastal California, Usa, Microbial Community, Jl Spackeen, Rachel E. Sipler, K Xu, Et Al, Da Bronk

VIMS Articles

Average global temperatures and carbon dioxide (CO2) levels are expected to increase in the coming decades. Implications for ocean ecosystems include shifts in microbial community structure and subsequent modifications to nutrient pathways. Studying how predicted future temperature and CO2 conditions will impact the biogeochemistry of the ocean is important because of the ocean’s role in regulating global climate. We determined how elevated temperature and CO2 affect uptake rates of nitrate, urea, and dissolved inorganic carbon (DIC) by 2 size classes (0.7-5.0 and >5.0 µm) of a microbial assemblage collected from coastal California, USA. This microbial community was incubated for 10 …

The Mystery Of Ocean Acidification, Patricia Thibodeau

Reports

Grades: 9-12 Subjects: Biology | Life Science | Environmental Science | Chemistry

This lesson plan invites middle-school students to solve a mystery: what is ocean acidification and how is it affecting marine life in the Antarctic? To solve the mystery, students will participate in an ocean acidification scavenger hunt, and propose hypotheses and arrive at their own conclusions with interpretation of real-time data from the Antarctic.

Resistivity, Magnetic Susceptibility And Sediment Characterization Of The York River Estuary In Support Of The Empirical Investigation Of The Factors Influencing Marine Applications Of Emi (Year 2 Of Serdp Project Mr-2409) Final Report., Grace M. Massey, Carl T. Friedrichs

Reports

Vessel and personnel support was provided for a series of cruises to three salinity regimes along the York River. Data and samples from a standard suite of hydrographic and sedimentological measurements, as well as electrical resistivity and magnetic susceptibility, were collected and analyzed for each location. These cruises provided opportunities to obtain information that is being used to quantify the unique marine contributions to the early time TEM noise, including conductivity variations in the water and variability in bottom sediment properties in real marine environments, for use in the parallel modeling and electromagnetic-induction sensor work ongoing in the same project. …

Using High-Resolution Glider Data And Biogeochemical Modeling To Investigate Phytoplankton Variability In The Ross Sea, Daniel Edward Kaufman

Dissertations, Theses, and Masters Projects

As Earth’s climate changes, polar environments experience a disproportionate share of extreme shifts. Because the Ross Sea shelf has the highest annual productivity of any Antarctic continental shelf, this region is of particular interest when striving to characterize current and future changes in Antarctic systems. However, understanding of mesoscale variability of biogeochemical patterns in the Ross Sea and how this variability affects assemblage dynamics is incomplete. Furthermore, it is unknown how the Ross Sea may respond to projected warming, reduced summer sea ice concentrations, and shallower mixed layers during the next century. to investigate these dynamics and explore their consequences …