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Full-Text Articles in Physical Sciences and Mathematics
Improving Modeled Light Attenuation (Kd) In A Land-Estuarine Ocean Biogeochemical Model For Chesapeake Bay, Jessica Turner, Carl T. Friedrichs, Marjorie A.M. Friedrichs
Improving Modeled Light Attenuation (Kd) In A Land-Estuarine Ocean Biogeochemical Model For Chesapeake Bay, Jessica Turner, Carl T. Friedrichs, Marjorie A.M. Friedrichs
Presentations
No abstract provided.
Chesapeake Bay Hypoxia Coastal Ocean Modeling Testbed, M.A.M. Friedrichs, Carl T. Friedrichs, I.D. Irby, A.J. Bever
Chesapeake Bay Hypoxia Coastal Ocean Modeling Testbed, M.A.M. Friedrichs, Carl T. Friedrichs, I.D. Irby, A.J. Bever
Presentations
No abstract provided.
Hypoxia Forecasts As A Tool For Chesapeake Bay Fisheries, Marjorie A.M. Friedrichs, A. J. Bever, Carl T. Friedrichs, R.R. Hood
Hypoxia Forecasts As A Tool For Chesapeake Bay Fisheries, Marjorie A.M. Friedrichs, A. J. Bever, Carl T. Friedrichs, R.R. Hood
Presentations
No abstract provided.
Hypoxia Forecasts As A Tool For Chesapeake Bay Fisheries, Marjorie A.M. Friedrichs, R.R. Hood, Carl T. Friedrichs, David R. Forrest
Hypoxia Forecasts As A Tool For Chesapeake Bay Fisheries, Marjorie A.M. Friedrichs, R.R. Hood, Carl T. Friedrichs, David R. Forrest
Presentations
The Estuarine Hypoxia component of the U.S. Integrated Ocean Observing System Coastal and Ocean Modeling Testbed (COMT) is evaluating existing hydrodynamic and water quality models used, or likely to be used, for operations in the Chesapeake Bay. As a proof-of-concept, an implementation of the Regional Ocean Modeling System in the Chesapeake Bay (ChesROMS) is linked to a simple respiration model for hypoxia (Hypoxia_SRM). The modeling system is presently being used to produce real-time nowcasts and short-term (3-day) hypoxia forecasts for the Chesapeake Bay, which are currently available on the Virginia Institute of Marine Science (VIMS) website. Workshops with citizen stakeholders …
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 …
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.
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 …
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.
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.
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.
Buoyant And Gravity-Driven Transport On The Waipaoa Shelf, J. M. Moriarty, Courtney K. Harris, Carl T. Friedrichs, M. G. Hadfield
Buoyant And Gravity-Driven Transport On The Waipaoa Shelf, J. M. Moriarty, Courtney K. Harris, Carl T. Friedrichs, M. G. Hadfield
Presentations
No abstract provided.
The Estuarine Hypoxia Component Of The Coastal Ocean Modeling Testbed (Comt), Marjy Friedrichs, Lyon Lanerolle, Carl T. Friedrichs, Raleigh Hood
The Estuarine Hypoxia Component Of The Coastal Ocean Modeling Testbed (Comt), Marjy Friedrichs, Lyon Lanerolle, Carl T. Friedrichs, Raleigh Hood
Presentations
Due to increased nutrient loads that are delivered to our coastal ecosystems, hypoxic events are becoming increasingly prevalent. In response, NOAA is working to monitor, understand and predict hypoxia in U.S. waters in order to develop strategies for forecasting these events and minimizing their detrimental effects. The Chesapeake Bay and its associated tidal tributaries, which together form one of the world’s largest and most important estuaries, is one of the coastal systems where degraded water quality and hypoxia are a major concern. Partially as a result of the number of public livelihoods affected by hypoxic events, the Chesapeake Bay is …
Skill Assessment Of Multiple Hypoxia Models In Chesapeake Bay And Implications For Management Decisions, I. D. Irby, M. Friedrichs, Carl Friedrichs, Raleigh Hood
Skill Assessment Of Multiple Hypoxia Models In Chesapeake Bay And Implications For Management Decisions, I. D. Irby, M. Friedrichs, Carl Friedrichs, Raleigh Hood
Presentations
The Chesapeake Bay Program (CBP) has used their coupled watershed-water quality modeling system to develop a set of Total Maximum Daily Loads (TMDLs) for nutrients and sediment in an effort to reduce eutrophication impacts which include decreasing the seasonal occurrence of hypoxia within the Bay. The CBP is now considering the use of a multiple model approach to enhance the confidence in their model projections and to better define uncertainty. This study statistically compares the CBP regulatory model with multiple implementations of the Regional Ocean Modeling System (ROMS) in terms of skill in reproducing monthly profiles of hydrodynamics, nutrients, chlorophyll …
Added Value Of Combining Multiple Optical And Acoustic Instruments When Characterizing Fine-Grained Estuarine Suspensions, G. M. Cartwright, C. T. Friedrichs, L. P. Sanford, S. J. Smith
Added Value Of Combining Multiple Optical And Acoustic Instruments When Characterizing Fine-Grained Estuarine Suspensions, G. M. Cartwright, C. T. Friedrichs, L. P. Sanford, S. J. Smith
Presentations
Various optical and acoustic instruments have specific advantages and limitations for characterizing suspensions, and when used together more information can be obtained than with one instrument alone. The LISST 100X, for example, is a powerful tool for estimating particle size distribution, but because of the inversion method used to determine the size distribution, it is difficult to distinguish two dominate populations that peak close to one another, especially among larger grain sizes. In the York River estuary, VA, additional information obtained through the deployment of a RIPScam camera system and an ADV along with the LISST 100X allowed differentiation between …
Skill Assessment Of Multiple Models In The Chesapeake Bay, I. D. Irby, M. Friedrichs, C. Feng, C. Friedrichs
Skill Assessment Of Multiple Models In The Chesapeake Bay, I. D. Irby, M. Friedrichs, C. Feng, C. Friedrichs
Presentations
No abstract provided.
Comparison Of Hydrodynamic And Water Quality Models Of The Chesapeake Bay: Results Of The Ioos Coastal Ocean Modeling Testbed, I Irby, M. Friedrichs, C. Feng, R. Hood
Comparison Of Hydrodynamic And Water Quality Models Of The Chesapeake Bay: Results Of The Ioos Coastal Ocean Modeling Testbed, I Irby, M. Friedrichs, C. Feng, R. Hood
Presentations
No abstract provided.
Skill Assessment Of Multiple Models In The Chesapeake Bay, I. D. Irby, M. Friedrichs, C. Feng, R. Hood
Skill Assessment Of Multiple Models In The Chesapeake Bay, I. D. Irby, M. Friedrichs, C. Feng, R. Hood
Presentations
No abstract provided.
Reworking Of Flood Deposits On The Waipaoa Shelf, New Zealand: Buoyant And Gravity-Driven Fluxes, J. M. Moriarty, Courtney K. Harris, Carl T. Friedrichs, M. G. Hadfield
Reworking Of Flood Deposits On The Waipaoa Shelf, New Zealand: Buoyant And Gravity-Driven Fluxes, J. M. Moriarty, Courtney K. Harris, Carl T. Friedrichs, M. G. Hadfield
Presentations
No abstract provided.
Applications Of Acoustics And Optics For The Characterization Of Suspended Particulate Matter Within An Estuarine Observing System, G. M. Cartwright
Applications Of Acoustics And Optics For The Characterization Of Suspended Particulate Matter Within An Estuarine Observing System, G. M. Cartwright
Presentations
No abstract provided.
Combining Observations And Models To Improve Estimates Of Chesapeake Bay Hypoxic Volume, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Combining Observations And Models To Improve Estimates Of Chesapeake Bay Hypoxic Volume, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Presentations
No abstract provided.
Combining Observations And Numerical Model Results To Improve Estimates Of Hypoxic Volume Within 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 Chesapeake Bay, A. J. Bever, M. A.M. Friedrichs, C. T. Friedrichs, M. E. Scully
Presentations
No abstract provided.
Spring-Neap Variation In Fecal Pellet Properties Within Surficial Sediment Of The York River Stuary, Virginia, E. A. Wei, L. M. Kraatz, Carl T. Friedrichs
Spring-Neap Variation In Fecal Pellet Properties Within Surficial Sediment Of The York River Stuary, Virginia, E. A. Wei, L. M. Kraatz, Carl T. Friedrichs
Presentations
Fecal pellet abundance was measured within the upper seabed of the York River Estuary as part of a larger study investigating relationships between fine sediment aggregates and bed erodibility. Sedimentalogical surveys were conducted twice a month during the spring and summer of 2011 to coincide with spring or neap tidal cycles. Particle size distributions were determined by sieving the sediment using three methods: 1) typical grain size analysis, 2) gentle agitation with seawater, 3) gentle agitation with deionized water. Each method used four sieves (150, 90, 63 and 45 microns) to constrain the size abundance of the particles. The study …
Intercomparison Of 3-D Models For Estuarine Hydrodynamics And Hypoxia Within The Us Ioos Super-Regional Coastal Modeling Testbed, Carl T. Friedrichs, A. J. Bever, M.A.M. Friedrichs, The Estuarine Hypoxia Team
Intercomparison Of 3-D Models For Estuarine Hydrodynamics And Hypoxia Within The Us Ioos Super-Regional Coastal Modeling Testbed, Carl T. Friedrichs, A. J. Bever, M.A.M. Friedrichs, The Estuarine Hypoxia Team
Presentations
No abstract provided.
Observations And Best-Fit Modeling Of Settling And Suspension Of Multiple Sediment Particle Types: York River, Virginia, K. A. Fall, Carl T. Friedrichs, M.A.M. Friedrichs
Observations And Best-Fit Modeling Of Settling And Suspension Of Multiple Sediment Particle Types: York River, Virginia, K. A. Fall, Carl T. Friedrichs, M.A.M. Friedrichs
Presentations
No abstract provided.
Spatial And Temporal Variations Of Sea Bed Sediment Erodibility On The Texas-Lousiana Shelf And Their Implications To The Formation Of Hypoxic Water, K. Xu, K. B. Briggs, Grace M. Cartwright, Carl T. Friedrichs
Spatial And Temporal Variations Of Sea Bed Sediment Erodibility On The Texas-Lousiana Shelf And Their Implications To The Formation Of Hypoxic Water, K. Xu, K. B. Briggs, Grace M. Cartwright, Carl T. Friedrichs
Presentations
No abstract provided.
In Situ Characterization Of Estuarine Suspended In The Presence Of Muddy Flocs And Pellets, Grace M. Cartwright, Carl T. Friedrichs, L. P. Sanford
In Situ Characterization Of Estuarine Suspended In The Presence Of Muddy Flocs And Pellets, Grace M. Cartwright, Carl T. Friedrichs, L. P. Sanford
Presentations
No abstract provided.
Tidal Flat Morphodynamics: A Synthesis, Carl T. Friedrichs
Tidal Flat Morphodynamics: A Synthesis, Carl T. Friedrichs
Presentations
No abstract provided.
Bed Erodibility As A Function Of Sediment Properties And Environmental Conditions Within The York River Estuary, L. M. Kraatz, Carl T. Friedrichs
Bed Erodibility As A Function Of Sediment Properties And Environmental Conditions Within The York River Estuary, L. M. Kraatz, Carl T. Friedrichs
Presentations
No abstract provided.