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The goals of these proposals are: 1. Measure the variability of optical properties in-space along a river mouth/inlet and observe the variability in time at a single position over a tidal cycle. 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particulate size distribution. 3. Relate the optical properties to the ocean reflectance so that algorithms to invert surface color to in-water constituents can be tested and improved., Prepared in collaboration with the Department of Oceanography, Dalhousie University, Halifax, Nova Scotia, Canada, and Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada.

The goal of the proposed work is to investigate the accuracy of a new method for estimating the bulk density of suspended particles in situ and non-invasively. The new method uses the commercially available LISST-100x particle size analyzer paired with a digital floc camera. It would enable collection of high temporal resolution estimates of particle bulk density.

Long-term Goals: The goal of our research is to improve our ability to assess and predict the distribution of water column optical properties in the coastal region. Objectives: Our research in the New River Tidal Inlet had three primary objectives: 1. Measure the variability of optical properties in-space along a river mouth/inlet and observe the variability in time at a single position over a tidal cycle; 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particle size distribution; 3. Relate the optical properties to the ocean reflectance, so algorithms to invert surface color to in-water constituents can be tested and improved.

Our research in the mouth of the Columbia River has four primary objectives: 1. Measure the variability of optical properties in-space in the mouth of the Columbia River on ebbing and flooding tides during a high flow period; 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particle size distribution; 3. Relate the optical properties to the ocean reflectance, so algorithms to invert surface color to in-water constituents can be tested and improved; 4. Investigate sediment parameters that optimize fit between derived suspended sediment distribution in the Columbia River mouth and the distribution produced by Delft-3D.

The goal of this research is to develop greater understanding of the how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. Achieving these goals will improve the skill of sediment transport models and hence prediction of underwater visibility., The original document contains color images.

The goal of this research is to develop greater understanding of how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column., The original document contains color images.

The goals of this proposal are: 1. Measure the variability of optical properties in-space along a river mouth/inlet and observe the variability in time at a single position over a tidal cycle. 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particulate size distribution. 3. Relate the optical properties to the ocean reflectance so that algorithms to invert surface color to in-water constituents can be tested and improved., The original document contains color images.

The goal of our research is to improve our ability to assess and predict the distribution of optical properties in the coastal region. Our research in the New River Tidal Inlet had three primary objectives: 1. Measure the variability of optical properties in-space along a river mouth/inlet and observe the variability in time at a single position over a tidal cycle; 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particle size distribution; 3. Relate the optical properties to the ocean reflectance, so algorithms to invert surface color to inwater constituents can be tested and improved., The original document contains color images.

The goal of our Tidal Flats research is to expand our understanding of the erosional and depositional processes that lead to exchange of mud between tidal channels and tidal flats. We also investigate the effect of sediment texture on sediment strength., The original document contains color images.

The goal of this research is to develop greater understanding of how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. Objectives: 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields., Prepared in cooperation with Dalhousie University, Department of Oceanography, Halifax, Nova Scotia, Canada.

The goal of our Tidal Flats research is to expand our understanding of the erosional and depositional processes that lead to exchange of mud between tidal channels and tidal flats. We also investigate the effect of sediment texture on sediment strength. Our research on Tidal Flats DRI had three primary objectives: 1. Improve understanding of how turbulence and sediment concentration affect the size-dependent depositional flux of sediment to the seabed on tidal flats. Based on our observations during the project, this objective has been broadened to include the effect of rainfall and runoff. 2. Improve understanding of how sediment texture and sorting in the seabed affect the size dependent erosional flux from the seabed on tidal flats. 3. Link our understanding of erosional and depositional sorting to spatial and temporal patterns of grain size on tidal flats.

The goal of this research is to develop greater understanding of how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. Objectives: 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields., Prepared in cooperation with Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada.

The goal of this research is to develop greater understanding of the how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. Achieving these goals will improve the skill of sediment transport models and hence prediction of underwater visibility. Objectives: 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields., Prepared in cooperation with Dalhousie University, Department of Oceanography, Halifax, Nova Scotia, Canada; Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada; and Woods Hole Oceanographic Institution, Woods Hole, MA.

The goal of this research is to measure the effects of varying amounts of suspended particulate near the sea floor on data transmission with a free space, omni-directional, optical link and to test the viability of communicating through the air-sea interface. A better understanding of turbulence and turbidity and their influence on the optical channel are critical to the development of optical communications in coastal waters. Objectives: 1. Deploy an optical telemetry system in a location where optical properties are measured by our collaborators. 2. Demonstrate optical telemetry through the air-sea interface. 3. Identify relationships between optical link performance and observed optical water properties., Prepared in cooperation with University of Maine, School of Marine Sciences, Orono, ME; Dalhousie University, Department of Oceanography, Halifax, Nova Scotia, Canada; and Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada.

In this Final Report on this Office of Naval Research contract, we demonstrate the successful completion of all proposed tasks. We have participated in a series of observational studies at the Woods Hole Martha's Vineyard Coastal Observatory where we collected high-quality physical, acoustical and optical data. The data has been processed demonstrating the close link between resuspension dynamics, particle aggregation and settling. Results indicate that contrary to existing models and interpretation, and based on theoretical, lab and field measurements, optical properties can predict suspended mass quite accurately due to the process of aggregation. Contrary to optical data, we find high frequency acoustics backscattering to be sensitive to aggregation suggesting that the ratio of acoustical to optical backscattering could provide a sensitive proxy to the degree of packaging of the suspended mass. Insight from this work will be applied shortly into an aggregation module in the community sediment transport model., Prepared in cooperation with Woods Hole Oceanographic Institution, Woods Hole, MA. The original document contains color images.

The goal of this research is to develop greater understanding of the dynamics of fluid mud and its role in the transport and deposition of sediment in coastal environments. In particular, we seek greater understanding of the processes that influence the formation and maintenance of fluid mud in energetic environments., FY10 Annual Reports of S & T efforts sponsored by the Ocean Battlespace Sensing S & T Department of the Office of Naval Research., The original document contains color images.

The goal of this research is to develop greater understanding of the how the flocculation of finegrained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. Achieving these goals will improve the skill of sediment transport models and their validation and hence visibility., Prepared in cooperation with Dalhousie University, Halifax, Nova Scotia, Canada; Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada; and Woods Hole Oceanographic Institution, Woods Hole, MA.

In this Final Report on this Office of Naval Research contract, we demonstrate the successful completion of all proposed tasks. We have participated in a series of observational studies at the Woods Hole Martha's Vineyard Coastal Observatory where we collected high-quality physical, acoustical and optical data. The data has been processed demonstrating the close link between resuspension dynamics, particle aggregation and settling. Results indicate that contrary to existing models and interpretation, and based on theoretical, lab and field measurements, optical properties can predict suspended mass quite accurately due to the process of aggregation. Contrary to optical data, we find high frequency acoustics backscattering to be sensitive to aggregation suggesting that the ratio of acoustical to optical backscattering could provide a sensitive proxy to the degree of packaging of the suspended mass. Insight from this work will be applied shortly into an aggregation module in the community sediment transport model., Prepared in cooperation with Dalhousie University, Nova Scotia; Bedford Institute of Oceanography, Nova Scotia; and Woods Hole Oceanographic Institution.

The goal of this research is to develop greater understanding of the dynamics of fluid mud and its role in the transport and deposition of sediment in coastal environments. In particular, we seek greater understanding of the processes that influence the formation and maintenance of fluid mud in energetic environments.

The goal of this research is to develop greater understanding of the dynamics of fluid mud and its role in the transport and deposition of sediment in coastal environments and on the continental margin. In particular, we seek greater understanding of the processes that influence the formation and maintenance of fluid mud in energetic environments.

The goal of our Tidal Flats research is to expand our understanding of the erosional and depositional processes that lead to exchange of mud between tidal channels and tidal flats and its impact on sediment strength. Our research on Tidal Flats DRI has two primary objectives: 1. Improve understanding of how turbulence and sediment concentration affect the size-dependent depositional flux of sediment to the seabed on tidal flats. 2. Improve understanding of how sediment texture and sorting in the seabed affect the size-dependent erosional flux from the seabed on tidal flats.

Long-term goals: To quantify and understand the effects of aggregation dynamics on the distribution of particles in the bottom boundary layer, and to understand how the properties of particles (composition, shape, and internal structure) affect their optical and acoustical properties. The objectives are: Obtain a set of acoustical and optical measurements that determines the evolution of the particle size distribution, obtain concurrent velocity, temperature and conductivity measurements sufficient to determine the fluid dynamical environment within which the particle size distribution evolves, and evaluate and improve a state-of-the-art model of particle dynamics by comparing model calculations with measurements.

The goal of this research is to develop greater understanding of the how the flocculation of finegrained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields., Prepared in cooperation with Dalhousie University, Halifax, Nova Scotia, Canada.

The goal of this research is to develop greater understanding of the how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. Objectives are to: 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields.The approach is to obtain measurements that will permit comparisons of the optical and acoustical signatures of suspended particles and inferences of the particle size distribution and its temporal evolution, concurrently with fluid dynamical measurements that determine the flow field within which the particles evolve. The instrumentation is mounted on bottom tripods and includes a 9-wavelength optical attenuation and absorption meter (WetLabs ac-9, with automated regular dissolved measurement for calibration independent particulate measurements), a LISST-100 laser diffraction particle sizer (Agrawal & Pottsmith 2000), a digital floc camera (DFC) (Curran et al. 2002b), a Tracor Acoustic Profiling System (TAPS, Holliday 1987), and an array of SonTek/YSI acoustic Doppler velocimeters (ADVs). Near-simultaneous measurements with and without a filter assure high-quality particulate spectral absorption and attenuation measurements with the ac-9. The LISST-100 and floc camera together provide particulate size distributions from 2.5 micrometers to 1 centimeter. The TAPS obtains range-gated, vertical profiles of acoustical backscatter intensity at a range of frequencies between 0.3 and 3.0 MHz. The TAPS and ADVs produce acoustical measurements over a wide range of frequencies that can be used to generate particle size distributions (Holliday, 1987; Hay and Sheng, 1992)., Prepared in cooperation with Dalhousie University, Halifax, Nova Scotia; Bedford Institute of Oceanography, Dartmouth, Nova Scotia and Woods Hole Oceanographic Institition, Woods Hole, MA.

LONG-TERM GOALS: To quantify and understand the effects of aggregation dynamics on the distribution of particles in the bottom boundary layer, and to understand how the properties of particles (composition, shape, and internal structure) affect their optical and acoustical properties. OBJECTIVES: * Obtain a set of acoustical and optical measurements that determines the evolution of the particle size distribution. * Obtain concurrent velocity, temperature and conductivity measurements sufficient to determine the fluid dynamical environment within which the particle size distribution evolves. * Evaluate and improve a state-of-the-art model of particle dynamics by comparing model calculations with measurements., Prepared in cooperation with University of Maine, Orono; Dalhousie University, Halifax, Nova Scotia; Bedford Institute of Oceanography, Dartmouth, Nova Scotia.

The goal of this research is to develop greater understanding of the how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. OBJECTIVES: 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields., Prepared in cooperation with Bedford Institute of Oceanography, Dartmouth, Nova Scotia.

The goal of this research is to develop greater understanding of the dynamics of fluid mud and its role in the transport and deposition of sediment on the continental margin. In particular, we seek greater understanding of the processes that influence the formation and maintenance of fluid mud in energetic environments. The research is a process-based study that addresses three primary objectives: * Determine controlling factors in the formation and destruction of fluid mud under a sheared flow, * Verify Richardson number dependence for suppression of turbulence and carrying capacity of a high-concentration suspension, * Evaluate effects of mixed grain size on high-concentration suspensions

The goals of this research are to understand size-sorting during erosion and deposition and to use this understanding to develop predictive models of where and when low-strength muds will accumulate in energetic coastal environments. Objectives: 1. To use our process-based parameterization of surficial seabed disaggregated inorganic grain size (DIGS) distributions to infer the extent of flocculation during deposition on energetic tidal flats. 2. To use time series of in situ suspended sediment properties, waves, and currents. to improve understanding of how turbulence, sediment concentration, and cohesion affect the size-dependent depositional flux of sediment to the seabed on energetic tidal flats. 3. To improve understanding of how sediment texture, cohesion, and sorting in the seabed affect the size-dependent erosional flux from the seabed on energetic tidal flats., Performed in cooperation with Dalhousie Univeristy, Nova Scotia, Canada.

The long-term goal is to quantify and understand the effects of aggregation dynamics on the distribution of particles in the bottom boundary layer, and to understand how the properties of particles (composition, shape, and internal structure) affect their optical and acoustical properties., Prepared in collaboration with the School of Marine Sciences at the Univ of Maine, Orono, the Department of Oceanography at Dalhousie Univ, Halifax, Nova Scotia, and Fisheries and Oceans Canada's Bedford Inst of Oceanography, Halifax, Nova Scotia. The original document contains color images.

The goal of this research is to develop greater understanding of the how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column., Prepared in collaboration with the Department of Oceanography, Dalhousie University Halifax, Nova Scotia and Fisheries and Oceans Canada at the Bedford Institute of Oceanography, Dartmouth, Nova Scotia. Additional ONR contract no. N00014-04-1-0235. The original document contains color images.

The goal of this research is to develop greater understanding of the dynamics of fluid mud and its role in the transport and deposition of sediment on the continental margin. In particular, we seek greater understanding of the processes that influence the formation and maintenance of fluid mud in energetic environments. The research is a process-based study that addresses three primary objectives: * Determine controlling factors in the formation and destruction of fluid mud under a sheared flow * Verify Richardson number dependence for suppression of turbulence and carrying capacity of a high-concentration suspension * Evaluate effects of mixed grain size on high-concentration suspensions., Performed in cooperation with Boston College, Chestnut Hill, MA.

The goal of this research is to develop greater understanding of the dynamics of fluid mud and its role in the transport and deposition of sediment on the continental margin. In particular, we seek greater understanding of the processes that influence the formation and maintenance of fluid muds in energetic environments. The research is a process-based study that addresses three primary objectives: (1) Determine controlling factors in the formation and destruction of fluid mud under a sheared flow; (2) Verify Richardson number dependence for suppression of turbulence and carrying capacity of a high-concentration suspension; (3) Evaluate effects of mixed grain size on high-concentration suspensions.

To quantify and understand the effects of aggregation dynamics on the distribution of particles in the bottom boundary layer, and to understand how the properties of particles (composition, shape, and internal structure) affect their optical and acoustical properties. * Obtain a set of acoustical and optical measurements that determines the evolution of the particle size distribution. * Obtain concurrent velocity, temperature and conductivity measurements sufficient to determine the fluid dynamical environment within which the particle size distribution evolves. * Evaluate and improve a state-of-the-art model of particle dynamics by comparing model calculations with measurements., Prepared in cooperation with University of Maine, Orono; Dalhousie University, Halifax, Nova Scotia; and Bedford Inst. of Oceanography, Fisheries and Oceans Canada, Dartmouth, Nova Scotia.

The goal of this research is to develop greater understanding of the how the flocculation of finegrained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column., Prepared in cooperation with Dalhousie Univ., Halifax, Nova Scotia and Bedford Inst. of Oceanography, Fisheries and Oceans Canada, Dartmouth, Nova Scotia. Sponsored in part by ONR grant N00014-04-1-0235. The original document contains color images.

The goal of this research is to develop greater understanding of the dynamics of fine-grained sediment and its role in the generation of sedimentary facies on the continental shelf. In particular, we seek greater understanding of the environmental processes that influence the degree of packaging of fine-grained sediment within flocs (floc fraction), and the role of boundary shear stress in determining the change in sediment size and sorting that makes the sand-mud transition recognizable acoustically as well as lithologically., Prepared in collaboration with Fisheries and Oceans Canada at the Bedford Institute of Oceanography, Dartmouth, Nova Scotia. The original document contains color images.

The goal of this research is to develop greater understanding of the how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column., Prepared in collaboration with the Department of Oceanography, Dalhousie University, Halifax, Nova Scotia, the Fisheries and Oceans Canada Bedford Institute of Oceanography, Dartmouth, Nova Scotia, and Woods Hole Oceanographic Institution Woods Hole, MA. Additional contract no. N00014-04-1-0233. The original document contains color images.

The goal of this research is to develop greater understanding of the dynamics of fine-grained sediment and its role in the generation of sedimentary facies on the continental shelf. In particular, we seek greater understanding of the environmental processes that influence the degree of packaging of fine-grained sediment within flocs (floc fraction), and the role of boundary shear stress in determining the change in sediment size and sorting that makes the sand-mud transition recognizable acoustically as well as lithologically., Prepared in collaboration with Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia.

The goal of this research is to develop greater understanding of the dynamics of fine-grained sediment and its role in the generation of sedimentary facies on the continental shelf. In particular, we seek greater understanding of the environmental processes that influence the degree of packaging of fine-grained sediment within flocs (floc fraction), and the role of boundary shear stress in determining the change in sediment size and sorting that makes the sand-mud transition recognizable acoustically as well as lithologically., Prepared in cooperation with Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada.

The goals of this research are to develop greater understanding of the fate of the sediment delivered to the continental shelf by the Eel River during floods and to refine methods for interpreting quantitatively the environmental record stored in grain size distributions of fine sediments on the shelf.

The long-term goals of this research are to develop and test a particle aggregation parameterization in turbid, river, discharge plumes. The proposed research has two objectives. The first is to monitor the evolution of in situ and disaggregated particle size distributions in the Eel River plume during major discharge events. The second is to develop and test a simple parameterization of particle aggregation that can be incorporated directly into dynamic plume models., Prepared in collaboration with the Bedford Institute of Oceanography, Dartmouth, Nova Scotia. See also ADM002252.