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Full-Text Articles in Physical Sciences and Mathematics
What Controls Bed Erodibility In Muddy, Partially-Mixed Estuaries? Insights From The York River, Virginia, Carl Friedrichs, Grace M. Cartwright, P.J. Dickhudt, Kelsey Fall
What Controls Bed Erodibility In Muddy, Partially-Mixed Estuaries? Insights From The York River, Virginia, Carl Friedrichs, Grace M. Cartwright, P.J. Dickhudt, Kelsey Fall
Presentations
Appropriate parameterization of time-dependent erodibility of muddy seabeds is a significant barrier to improved understanding and accurate modeling of sediment dynamics in estuaries and other coastal regions. In an effort to better understand controls on muddy seabed erodibility, bed erodibility and associated bed sediment properties have been measured by our group on cores collected on dozens of cruises over the last decade in the York Estuary. We have also inferred time-varying erodibility indirectly in the York Estuary over several years by vertically integrating observations of tidally-varying suspended sediment concentration. This presentation synthesizes the results of these long-term observations in this …
Evaluating The Effects Of Cohesive Processes On Sediment Distribution In An Idealized, Partially-Mixed Estuary Using A Numerical Model, Danielle Tarpley, Courtney Harris, Carl Friedrichs
Evaluating The Effects Of Cohesive Processes On Sediment Distribution In An Idealized, Partially-Mixed Estuary Using A Numerical Model, Danielle Tarpley, Courtney Harris, Carl Friedrichs
Presentations
An idealized two-dimensional model is designed to represent a longitudinal section of a partially-mixed estuary, accounting for a freshwater source, tides, and estuarine circulation, but neglecting across-channel variations. The Community Sediment Transport Modeling System (CSTMS) is used to simulate suspended transport, erosion, and deposition within the Regional Ocean Modeling System (ROMS). This version of the model also includes cohesive processes such as consolidation and swelling of the sediment bed; sediment-induced stratification; and variable settling velocities. To better understand the processes controlling fine-grained sediment transport in the York River, VA, the primary features of the idealized estuary mimic that system, and …
Challenges Associated With Modeling Low-Oxygen Waters In Chesapeake Bay: A Multiple Model Comparison, I.D. Irby, M. A.M. Friedrichs, Carl T. Friedrichs, Comt Estuarine Hypoxia Team
Challenges Associated With Modeling Low-Oxygen Waters In Chesapeake Bay: A Multiple Model Comparison, I.D. Irby, M. A.M. Friedrichs, Carl T. Friedrichs, Comt Estuarine Hypoxia Team
Presentations
As ecosystem and water quality models are becoming more frequently used for operational forecasts and scenario-based management decisions, it is important to understand the relative strengths and limitations of existing models of varying complexity. To this end, simulations of the Chesapeake Bay from eight threedimensional coupled hydrodynamic-oxygen models have been statistically compared to each other and to two years of historical monitoring data. Results show that although models have difficulty resolving the variables typically thought to be the main drivers of dissolved oxygen variability (stratification, nutrients, and chlorophyll), all eight models have significant skill in reproducing the mean and seasonal …
Estuarine Sediment Dynamics, C. T. Friedrichs
Tidal Flat Morphodynamics: A Synthesis, C. T. Friedrichs
Tidal Flat Morphodynamics: A Synthesis, C. T. Friedrichs
Presentations
No abstract provided.
Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River, Virginia, Usa, K. A. Fall, C. T. Friedrichs, G. M. Cartwright, D. G. Bowers
Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River, Virginia, Usa, K. A. Fall, C. T. Friedrichs, G. M. Cartwright, D. G. Bowers
Presentations
The Chesapeake Bay and its associated tidal tributaries, which together form one of the United States’ largest and most important estuaries, are among the many coastal systems where degraded water clarity is a major concern. Despite long-term decreases in sediment input, water clarity over the last 20 years has continued to deteriorate in the Bay and its tributaries (Williams et al., 2010). Analysis of long-term monitoring data (Wang et al., 2010) found that the concentration of total suspended solids (TSS), the regulatory indicator of ‘suspended sediment pollution’, is about as likely to be positively or negatively correlated to sediment loads …
Identification Of Suspended Resilient Pellets In Particles Tracked By A Particle Image Camera System (Pics) In A Muddy Estuary, Grace M. Cartwright, Kelsey A. Fall, Carl T. Friedrichs
Identification Of Suspended Resilient Pellets In Particles Tracked By A Particle Image Camera System (Pics) In A Muddy Estuary, Grace M. Cartwright, Kelsey A. Fall, Carl T. Friedrichs
Presentations
The Particle Imaging Camera System (PICS) was designed to allow for the measurement of the settling velocity of individual particles in situ by using the smaller particles (< density < 1800kg/m3 ). This classification system, while adequate for suspended dredge plumes, needs to be revisited when the PICS is used in a muddy estuary, such as the York River Estuary, Virginia. Figure 1B shows the settling velocities of particles tracked within a video captured 2.5m from the surface in the Clay Bank region of the York River, plotted against their equivalent spherical diameters. While most of the particles are classified as flocs, as indicated by the blue dots in Figure 1C and the peak in the relative number of particles in Figure 1E, there is still a large number of particles classified as “bed aggregates” (red dots). This number of higher density particles may be unexpected, as this video was captured 4.25m over a “muddy bed” in a natural system with a flood current of 40cm/s. However, biologically compacted mud in the form of resilient pellets (see Figure 2) may be the answer. Bed sediments from five sediment cruises during this study period (Aug 2012 – Nov 2014) were found to be comprised of 86-96% mud (Figure 3A). However, 9-14% of the mud was packaged as resilient pellets (Figure 3B). Sediment captured 38cm above the bed by traps deployed on tripods were found to have 92-98% mud, with 4-14% of the mud packaged as resilient pellets (Figures 3A and B). Pellets isolated from the Apr to Jul 2014 trap were sampled with the PICS to determine the distribution of settling velocities (Ws), particle densities, and the ratio of the long and short axis of the particles. This will be used to identify the pellets in PICS videos captured during the five 6h anchor stations (black lines in Figure 3) where three depths were sampled each hour.
Controls On Bed Erodibility In A Muddy, Partially-Mixed Estuary: York River, Virginia, Usa, Carl T. Friedrichs, Grace M. Cartwright, Patrick J. Dickhut, Kelsey A. Fall
Controls On Bed Erodibility In A Muddy, Partially-Mixed Estuary: York River, Virginia, Usa, Carl T. Friedrichs, Grace M. Cartwright, Patrick J. Dickhut, Kelsey A. Fall
Presentations
Appropriate parameterization of time-dependent erodibility of muddy seabeds is a significant barrier to improved understanding and accurate modelling of sediment dynamics in estuaries and other coastal regions. In an effort to better understand controls on muddy seabed erodibility, bed erodibility and associated bed sediment properties have been measured by our group on cores collected on dozens of cruises over the last decade in the York Estuary (e.g., Dickhudt et al., 2009, 2011; Kraatz, 2013). We have also inferred time-varying erodibility indirectly in the York Estuary over several years by vertically integrating observations of tidally-varying suspended sediment concentration (e.g. Friedrichs et …
Tidal Flat Morphodynamics: A Synthesis, Carl T. Friedrichs
Tidal Flat Morphodynamics: A Synthesis, Carl T. Friedrichs
Presentations
Tidal flats commonly occur along coasts where the tidal range is large relative to typical wave height. They can be found where hydrodynamic energy is high or low, where sediments are sandy or muddy, and where shorelines are prograding, retreating, or stable. The study of the morphology and evolution of tidal flats is particularly well suited in the context of morphodynamics since characteristics such as profile shape, bed slope, and grain size clearly and systematically vary as a function of sediment supply and wave and tidal forcing, and the nature of wave- and tide-induced velocities across tidal flats is, in …
Comt Chesapeake Bay Hypoxia Modeling, Marjorie A.M. Friedrichs, I. Irby, A. Bever, M. Scully
Comt Chesapeake Bay Hypoxia Modeling, Marjorie A.M. Friedrichs, I. Irby, A. Bever, M. Scully
Presentations
No abstract provided.
Challenges Associated With Operational Modeling Of Low-Oxygen Waters In Chesapeake Bay: Results From A Multiple Modeling Effort, I. D. Irby, M. A.M. Friedrichs, C. T. Friedrichs
Challenges Associated With Operational Modeling Of Low-Oxygen Waters In Chesapeake Bay: Results From A Multiple Modeling Effort, I. D. Irby, M. A.M. Friedrichs, C. T. Friedrichs
Presentations
No abstract provided.
Including Fine-Grained Sediment Processes Within Numerical Representations Of A Partially-Mixed Estuary, The York River, Virginia, Danielle Tarpley, Courtney Harris, Carl Friedrichs, Kelsey Fall
Including Fine-Grained Sediment Processes Within Numerical Representations Of A Partially-Mixed Estuary, The York River, Virginia, Danielle Tarpley, Courtney Harris, Carl Friedrichs, Kelsey Fall
Presentations
The Community Sediment Transport Modeling System (CSTMS) is being used to represent conditions in the York River, Virginia, a partially-mixed tidal tributary of Chesapeake Bay. Our modeling approach includes both an idealized two-dimensional longitudinal representation of the estuary, and a more realistic full three-dimensional model of the York River. Both have been implemented using versions of the Regional Ocean Modeling System (ROMS). Our modeling efforts have been motivated by a rich set of observation data from in-situ measurements made by acoustic Doppler velocimeters (ADVs), a pulse coherent acoustic Doppler profiler (PC-ADP), a laser in-situ scattering and transmissometry (LISST), and a …
Factors Affecting Munitions Mobility Underwater, C. Friedrichs
Factors Affecting Munitions Mobility Underwater, C. Friedrichs
Presentations
No abstract provided.
Skill Assessment Of Multiple Hydrodynamic-Dissolved Oxygen Models In Chesapeake Bay, I. Irby, M. A.M. Friedrichs, C. T. Friedrichs
Skill Assessment Of Multiple Hydrodynamic-Dissolved Oxygen Models In Chesapeake Bay, I. Irby, M. A.M. Friedrichs, C. T. Friedrichs
Presentations
No abstract provided.
The Estuarine Hypoxia Component Of The Coastal Ocean Modeling Testbed: Providing Environmental Intelligence To Decision-Makers In The Chesapeake Bay Region, Marjorie A.M. Friedrichs, L. Lanerolle, Carl T. Friedrichs, R. Hood
The Estuarine Hypoxia Component Of The Coastal Ocean Modeling Testbed: Providing Environmental Intelligence To Decision-Makers In The Chesapeake Bay Region, Marjorie A.M. Friedrichs, L. Lanerolle, Carl T. Friedrichs, R. Hood
Presentations
No abstract provided.
Introduction To The Research Capabilities Of The Vims Coastal Hydrodynamics & Sediment Dynamics (Chsd) Lab, G. M. Cartwright, K. A. Fall, C. T. Friedrichs, D. Tarpley
Introduction To The Research Capabilities Of The Vims Coastal Hydrodynamics & Sediment Dynamics (Chsd) Lab, G. M. Cartwright, K. A. Fall, C. T. Friedrichs, D. Tarpley
Presentations
No abstract provided.
What Controls Bed Erodibility In Muddy Estuaries? Insights From The York River, Virginia, C. T. Friedrichs, K. A. Fall, R. J. Diaz, P. Dickhut
What Controls Bed Erodibility In Muddy Estuaries? Insights From The York River, Virginia, C. T. Friedrichs, K. A. Fall, R. J. Diaz, P. Dickhut
Presentations
Appropriate parameterization of time-dependent erodibility of muddy seabeds is a significant barrier to improved understanding and accurate modeling of sediment dynamics in estuaries and other coastal regions. In an effort to better understand controls on muddy seabed erodibility, bed erodibility and associated bed sediment properties have been measured by our group on cores collected on dozens of cruises over the last decade in the York Estuary. We have also inferred time-varying erodibility indirectly in the York Estuary over several years by vertically integrating observations of tidally-varying suspended sediment concentration. This presentation synthesizes the results of these long-term observations in this …
Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River Estuary, Virginia, K. A. Fall, C. T. Friedrichs, G. M. Cartwright
Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River Estuary, Virginia, K. A. Fall, C. T. Friedrichs, G. M. Cartwright
Presentations
No abstract provided.
Controls On Bed Erodibility In The York River Estuary, C. T. Friedrichs, Grace M. Cartwright, R. J. Diaz, P. J. Dickhut
Controls On Bed Erodibility In The York River Estuary, C. T. Friedrichs, Grace M. Cartwright, R. J. Diaz, P. J. Dickhut
Presentations
No abstract provided.
Controls On Suspended Particle Properties And Water Clarity In The York River Estuary, Virginia, K. A. Fall, C. T. Friedrichs, G. M. Cartwright, D. G. Bowers
Controls On Suspended Particle Properties And Water Clarity In The York River Estuary, Virginia, K. A. Fall, C. T. Friedrichs, G. M. Cartwright, D. G. Bowers
Presentations
No abstract provided.
Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within Chesapeake Bay, Usa, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within Chesapeake Bay, Usa, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Presentations
No abstract provided.
The Development And The Capabilities Of The Community Sediment Transport Modeling System (Cstms) For The York River Estuary, Virginia, Danielle Tarpley, K. Fall, Courtney K. Harris, Carl T. Friedrichs
The Development And The Capabilities Of The Community Sediment Transport Modeling System (Cstms) For The York River Estuary, Virginia, Danielle Tarpley, K. Fall, Courtney K. Harris, Carl T. Friedrichs
Presentations
No abstract provided.
What Controls Bed Erodibility In Muddy, Partially-Mixed Tidal Estuaries?, C. Friedrichs, Grace Cartwright, R. Diaz, K. Fall
What Controls Bed Erodibility In Muddy, Partially-Mixed Tidal Estuaries?, C. Friedrichs, Grace Cartwright, R. Diaz, K. Fall
Presentations
No abstract provided.
Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River, Virginia, Usa, K. A. Fall, C. T. Friedrichs, G. M. Cartwright, D. G. Bowers
Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River, Virginia, Usa, K. A. Fall, C. T. Friedrichs, G. M. Cartwright, D. G. Bowers
Presentations
No abstract provided.
Estuarine Sediment Dynamics, C. T. Friedrichs
Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within Chesapeake Bay, Usa, A. J. Bever, M A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within Chesapeake Bay, Usa, A. J. Bever, M A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Presentations
No abstract provided.
Comt Chesapeake Bay Hypoxia Modeling, M. Friedrichs, C. Friedrichs, R. Hood, L. Lanerolle
Comt Chesapeake Bay Hypoxia Modeling, M. Friedrichs, C. Friedrichs, R. Hood, L. Lanerolle
Presentations
No abstract provided.
Skill Assessment Of Multiple Hypoxia Models In Chesapeake Bay And Implications For Management Decisions, I. D. Irby, M. A.M. Friedrichs, C. T. Friedrichs, R. Hood
Skill Assessment Of Multiple Hypoxia Models In Chesapeake Bay And Implications For Management Decisions, I. D. Irby, M. A.M. Friedrichs, C. T. Friedrichs, R. Hood
Presentations
No abstract provided.
Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within The Chesapeake Bay, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within The Chesapeake Bay, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Presentations
No abstract provided.
Bathymetry Controls On The Location Of Hypoxia Facilitate Possible Real-Time Hypoxic Volume Monitoring In The Chesapeake Bay, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Bathymetry Controls On The Location Of Hypoxia Facilitate Possible Real-Time Hypoxic Volume Monitoring In The Chesapeake Bay, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Presentations
No abstract provided.