Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
- Publication
Articles 1 - 21 of 21
Full-Text Articles in Environmental Sciences
Hydrodynamics And Morphology Of Equilibrium Tidal Freshwater Channels, Carl Friedrichs
Hydrodynamics And Morphology Of Equilibrium Tidal Freshwater Channels, Carl Friedrichs
Presentations
This presentation addresses the dynamics and morphology of near-equilibrium tidal freshwater channels. The dynamics considered are based on sectionally-averaged current velocity and a barotropic momentum balance. A series of geometries are examined which attempt to encompass generic, reasonably realistic scenarios for tidal fresh water channels found in nature. This work presents and scales the governing equations of mass and momentum conservation. An essential step in this process is the identification of key length scales, corresponding inverse length scales (or "spatial rates of change"), and dimensionless ratios to be used subsequently to determine when and where to keep or neglect various …
2011 Chesapeake Bay Sav Coverage, Sav Data Administrator, Virginia Institute Of Marine Science
2011 Chesapeake Bay Sav Coverage, Sav Data Administrator, Virginia Institute Of Marine Science
Data
Abstract: The 2011 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been …
Evaluating The Capabilities Of The Second Generation Pics Settling Column Floc Camera In A Muddy Tidal Estuary, York River, Virginia, Usa, Grace M. Cartwright, S. Jarrell Smith, Carl T. Friedrichs, Kelsey A. Fall
Evaluating The Capabilities Of The Second Generation Pics Settling Column Floc Camera In A Muddy Tidal Estuary, York River, Virginia, Usa, Grace M. Cartwright, S. Jarrell Smith, Carl T. Friedrichs, Kelsey A. Fall
Presentations
No abstract provided.
Acoustic Scattering To Measure Dispersed Oil Droplet Size And Sediment Particle Size, Paul D. Panetta, Leslie Bland, Grace M. Cartwright, Carl T. Friedrichs
Acoustic Scattering To Measure Dispersed Oil Droplet Size And Sediment Particle Size, Paul D. Panetta, Leslie Bland, Grace M. Cartwright, Carl T. Friedrichs
Presentations
No abstract provided.
Dual Use Of A Sediment Mixing Tank For Calibrating Acoustic Backscatter And Direct Doppler Measurement Of Settling Velocity, Grace M. Cartwright, Carl T. Friedrichs, Paul D. Panetta
Dual Use Of A Sediment Mixing Tank For Calibrating Acoustic Backscatter And Direct Doppler Measurement Of Settling Velocity, Grace M. Cartwright, Carl T. Friedrichs, Paul D. Panetta
Presentations
While the Acoustic Doppler Velocimeter (ADV) is designed to determine fluid velocity, it is important to recognize that it is actually the velocity of the scatterers themselves that is measured. Thus in a calibration tank designed to relate sediment-induced backscatter to sediment concentration, the vertical velocity registered by an ADV at a given point is actually the true fluid velocity plus the sediment’s settling velocity. And absent net vertical volume flux, the average vertical velocity registered by an ADV across a horizontal plane is equal to the mean sediment settling velocity. For this study, a series of ADV calibrations were …
Relationships Between Erodibility And Fine-Grained Seabed Properties On Tidal To Seasonal Time-Scales, York River Estuary, Virginia, Usa, Lindsey M. Kraatz, Carl T. Friedrichs, Grace M. Cartwright, Kelsey A. Fall
Relationships Between Erodibility And Fine-Grained Seabed Properties On Tidal To Seasonal Time-Scales, York River Estuary, Virginia, Usa, Lindsey M. Kraatz, Carl T. Friedrichs, Grace M. Cartwright, Kelsey A. Fall
Presentations
No abstract provided.
Controls On Particle Settling Velocity And Bed Erodibility In The Presence Of Muddy Flocs And Pellets As Inferred By Advs, York River Estuary, Virginia, Usa, Kelsey A. Fall, Carl T. Friedrichs, Grace M. Cartwright
Controls On Particle Settling Velocity And Bed Erodibility In The Presence Of Muddy Flocs And Pellets As Inferred By Advs, York River Estuary, Virginia, Usa, Kelsey A. Fall, Carl T. Friedrichs, Grace M. Cartwright
Presentations
No abstract provided.
Damping Of Turbulence By Suspended Sediment: Ramifications Of Under-Saturated, Critically-Saturated, And Over-Saturated Conditions, Carl T. Friedrichs
Damping Of Turbulence By Suspended Sediment: Ramifications Of Under-Saturated, Critically-Saturated, And Over-Saturated Conditions, Carl T. Friedrichs
Presentations
No abstract provided.
Combining Observational And Numerical Model Results To Improve Estimates Of Hypoxic Volume In Chesapeake Bay, A. J. Bever, Marjorie A.M. Friedrichs, Carl T. Friedrichs, M. E. Scully
Combining Observational And Numerical Model Results To Improve Estimates Of Hypoxic Volume In Chesapeake Bay, A. J. Bever, Marjorie A.M. Friedrichs, Carl T. Friedrichs, M. E. Scully
Presentations
No abstract provided.
Spatial And Temporal Trends In Tidal Flat Shape In San Francisco Bay, J. A. Bearman, Carl T. Friedrichs, B. E. Jaffe, A. C. Foxgrover
Spatial And Temporal Trends In Tidal Flat Shape In San Francisco Bay, J. A. Bearman, Carl T. Friedrichs, B. E. Jaffe, A. C. Foxgrover
Presentations
No abstract provided.
Results Of The Us Ioos Testbed For Comparison Of Hydrodynamic And Dissolved Oxygen Models Of The Chesapeake Bay, M.A.M. Friedrichs, A. J. Bever, M. E. Scully, W. Long
Results Of The Us Ioos Testbed For Comparison Of Hydrodynamic And Dissolved Oxygen Models Of The Chesapeake Bay, M.A.M. Friedrichs, A. J. Bever, M. E. Scully, W. Long
Presentations
Results from multiple 3-D hydrodynamic and dissolved oxygen models for Chesapeake Bay have been compared to each other and to EPA monitoring data for the years 2004 and 2005. On seasonal time-scales, the models all do well in capturing fundamental aspects of the hydrodynamic and oxygen fields, although the intensity of the pycnocline is underestimated. Models with constant net respiration independent of nutrient supply reproduce hypoxia nearly as well as much more complex, nutrient-dependent ecological models. Seasonal variation in DO was insensitive to seasonal cycles in the respiration rate, freshwater input, and density stratification. Rather, seasonal variation in DO was …
Use Of Acoustic Doppler Velocimeters (Advs) To Infer Relationships Among Fine Sediment Settling, Bed Erodibility And Particle Type, York River Estuary, Va, K. A. Fall, Carl T. Friedrichs, Grace M. Cartwright
Use Of Acoustic Doppler Velocimeters (Advs) To Infer Relationships Among Fine Sediment Settling, Bed Erodibility And Particle Type, York River Estuary, Va, K. A. Fall, Carl T. Friedrichs, Grace M. Cartwright
Presentations
Bed erodibility and particle settling velocity are key factors influencing fine sediment dynamics in coastal and estuarine environments. In order to better constrain inherently complex, temporally-varying relationships among hydrodynamics, bed properties and particle types, near-bed ADVs have been maintained in the York River Estuary since 2006. The ADVs provide measurements of bottom stress, suspended sediment concentration (C, via calibrated backscatter), and particle settling velocity (Ws, via a Rouse balance). By assuming Ws to be the combined result of rapidly settling fecal pellets plus more slowly settling flocs, the time-varying fraction of pellets versus flocs can be estimated. Vertical integration of …
Dual Use Of A Sediment Mixing Tank For Calibrating Acoustic Backscatter And Direct Doppler Measurement Of Settling Velocity, Grace M. Cartwright, Carl T. Friedrichs, P. D. Panetta
Dual Use Of A Sediment Mixing Tank For Calibrating Acoustic Backscatter And Direct Doppler Measurement Of Settling Velocity, Grace M. Cartwright, Carl T. Friedrichs, P. D. Panetta
Presentations
While the Acoustic Doppler Velocimeter (ADV) is designed to determine fluid velocity, it is important to recognize that it is actually the velocity of the scatterers themselves that is measured. Thus in a calibration tank designed to relate sediment-induced backscatter to sediment concentration, the vertical velocity registered by an ADV at a given point is actually the true fluid velocity plus the sediment’s settling velocity. And absent net vertical volume flux, the average vertical velocity registered by an ADV across a horizontal plane is equal to the mean sediment settling velocity. For this study, a series of ADV calibrations were …
Relationships Between Erodibility And Fine-Grained Seabed Properties On Tidal To Seasonal Time-Scales, York River Estuary, Virginia, L. M. Kraatz, Carl T. Friedrichs, Grace M. Cartwright, K. A. Fall
Relationships Between Erodibility And Fine-Grained Seabed Properties On Tidal To Seasonal Time-Scales, York River Estuary, Virginia, L. M. Kraatz, Carl T. Friedrichs, Grace M. Cartwright, K. A. Fall
Presentations
The complex bio-geo-physical nature of muddy particles in coastal and estuarine environments has limited our understanding of finegrained sediment dynamics. An ongoing sedimentalogical study within the York River Estuary is investigating controls on cohesive bed erodibility by assessing changes in seabed properties over varying timescales. During the spring and summer of 2010 and 2011, multiple GOMEX box cores were collected and subsampled for grain size, fecal pellet content, Gust chamber erodibility, and water content. Initial findings suggest that erodibility of the seabed increased during periods following seasonal deposition events. Higher erodibility was also generally found to coincide with peak spring …
Gis Data: City Of Alexandria Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Gis Data: City Of Alexandria Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Data
The 2012 Tidal Marsh Inventory update for City of Alexandria, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.
Gis Data: City Of Fairfax County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Gis Data: City Of Fairfax County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Data
The 2012 Tidal Marsh Inventory update for Fairfax County, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.
Gis Data: Westmoreland County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Carl Hershner, Sharon A. Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, David Weiss
Gis Data: Westmoreland County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Carl Hershner, Sharon A. Killeen, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, David Weiss
Data
The 2012 Tidal Marsh Inventory update for Westmoreland County, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data
Gis Data: City Of Virginia Beach, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon A. Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt
Gis Data: City Of Virginia Beach, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon A. Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt
Data
The 2012 Tidal Marsh Inventory update for Virginia Beach, VA was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.
Gis Data: Prince William County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon A. Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Gis Data: Prince William County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon A. Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Data
The 2012 Tidal Marsh Inventory update for Prince William County, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.
Gis Data: Mathews County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss
Gis Data: Mathews County, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky, Daniel E. Schatt, David Weiss
Data
The 2012 Tidal Marsh Inventory update for Mathews County, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.
Gis Data: City Of Hampton, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Gis Data: City Of Hampton, Virginia Tidal Marsh Inventory, Marcia Berman, Harry Berquist, Sharon Killeen, Carl Hershner, Karinna Nunez, Karen Reay, Tamia Rudnicky
Data
The 2012 Tidal Marsh Inventory update for City of Hampton, Virginia was generated using on-screen digitizing techniques in the most recent version of ArcGIS® - ArcMap while viewing conditions observed in the most recent imagery from the Virginia Base Mapping Program (VBMP). Dominant plant community types were primarily determined during field surveys from shallow-draft boats moving along the shoreline. Land-based surveys were performed in some locations. One shapefile is developed that portrays tidal marsh areas represented as polygons. A metadata file accompanies the shapefile to define attribute accuracy, data development, and any use restrictions that pertain to the data.