Richard P Signell, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 90
Modeling sand bank formation around tidal headlands Modeling sand bank formation around tidal headlands
Sandbanks are often found in the vicinity of coastal headlands around which tidal flows are strong enough to generate significant tidally-forced residual eddies, typically with scales of 2-10 km. One popular hypothesis is that these sandbanks are generated by a 'tidal stirring' mechanism in which the inward-directed pressure gradient associated with these residual eddies produces an...
Authors
Richard P. Signell, Courtney K. Harris
Circulation and sediment transport in the vicinity of the Hudson Shelf Valley Circulation and sediment transport in the vicinity of the Hudson Shelf Valley
Sediment transport in the Hudson Shelf Valley and on the adjacent Long Island Shelf are evaluated using available data along with a three-dimensional wind-driven circulation model and a one-dimensional sediment transport model. Winds from the northwest drive currents up the Hudson Shelf Valley, while winds from the east produce weaker currents directed down the valley. Consistent with...
Authors
Courtney K. Harris, Richard P. Signell
Seafloor environments in the Long Island Sound estuarine system Seafloor environments in the Long Island Sound estuarine system
Four categories of modern seafloor sedimentary environments have been identified and mapped across the large, glaciated, topographically complex Long Island Sound estuary by means of an extensive regional set of sidescan sonographs, bottom samples, and video-camera observations and supplemental marine-geologic and modeled physical-oceanographic data. (1) Environments of erosion or...
Authors
H.J. Knebel, R. P. Signell, R.R. Rendigs, L.J. Poppe, J. H. List
Construction of digital bathymetry for the Gulf of Maine Construction of digital bathymetry for the Gulf of Maine
No abstract available.
Authors
Ed T. Roworth, Rich P. Signell
Hydrodynamic forcing and sediment character in Boston Harbor Hydrodynamic forcing and sediment character in Boston Harbor
Calculated annual excess skin friction stress at various locations in Quincy Bay (outer Boston Harbor) was found to be correlated positively with sediment sand content. The correlation was optimized when a critical shear stress (??c) of 0.085 Pa was assumed for the bay. The excess shear stress was correlated negatively with sediment lead (Pb) and polychlorinated biphenyl (PCB)...
Authors
T.M. Ravens, O.S. Madsen, R. P. Signell, E.E. Adams, P.M. Gschwend
Modeling waves and circulation in Lake Pontchartrain, Louisiana Modeling waves and circulation in Lake Pontchartrain, Louisiana
The U.S. Geological Survey is conducting a study of storm-driven sediment resuspension and transport in Lake Pontchartrain, Louisiana. Two critical processes related to sediment transport in the lake are (1) the resuspension of sediments due to wind-generated storm waves and (2) the movement of resuspended material by lake currents during storm wind events. The potential for sediment...
Authors
Richard P. Signell, Jeffrey H. List
Lateral trapping of sediment in partially mixed estuary Lateral trapping of sediment in partially mixed estuary
No abstract available.
Authors
W. R. Geyer, R. P. Signell, G. C. Kineke
The wind-forced response on a buoyant coastal current: Observations of the western Gulf of Maine plume The wind-forced response on a buoyant coastal current: Observations of the western Gulf of Maine plume
The Freshwater plume in the western Gulf of Maine is being studied as part of an interdisciplinary investigation of the physical transport of a toxic alga. A field program was conducted in the springs of 1993 and 1994 to map the spatial and temporal patterns of salinity, currents and algal toxicity. The observations suggest that the plume's cross-shore structure varies markedly as a...
Authors
D.A. Fong, W.R. Geyer, R. P. Signell
Physical processes affecting the sedimentary environments of Long Island Sound Physical processes affecting the sedimentary environments of Long Island Sound
A modeling study was undertaken to simulate the bottom tidal-, wave-, and wind-driven currents in Long Island Sound in order to provide a general physical oceanographic framework for understanding the characteristics and distribution of seafloor sedimentary environments. Tidal currents are important in the funnel-shaped eastern part of the Sound, where a strong gradient of tidal-current...
Authors
R. P. Signell, H.J. Knebel, J. H. List, A.S. Farris
Effect of wave-enhanced bottom friction on storm-driven circulation in Massachusetts Bay Effect of wave-enhanced bottom friction on storm-driven circulation in Massachusetts Bay
Massachusetts Bay is a shallow (35 m average depth) semienclosed embayment, roughly 100 ?? 50 km, which opens into the Gulf of Maine at its eastern boundary. Surface waves associated with winter storm winds from the northeast cause large sediment resuspension events, and wave and circulation fields during these events have a quasi-steady response to the wind stress. Coupled wave...
Authors
R. P. Signell, J. H. List
Coupled physical-biological models for the study of harmful algal blooms Coupled physical-biological models for the study of harmful algal blooms
No abstract available.
Authors
Peter J.S. Franks, Richard P. Signell
Seafloor environments in Cape Cod Bay, a large coastal embayment Seafloor environments in Cape Cod Bay, a large coastal embayment
Cape Cod Bay is a glacial, semi-enclosed embayment that has a patchy distribution of modern seafloor sedimentary environments of erosion or nondeposition, deposition, and sediment reworking. Sidescan-sonar records and supplemental bathymetric, sedimentary, subbottom, and physical-oceanographic data indicate that the characteristics and distribution of these three categories of bottom...
Authors
H.J. Knebel, R.R. Rendigs, J. H. List, Richard P. Signell
Science and Products
Filter Total Items: 90
Modeling sand bank formation around tidal headlands Modeling sand bank formation around tidal headlands
Sandbanks are often found in the vicinity of coastal headlands around which tidal flows are strong enough to generate significant tidally-forced residual eddies, typically with scales of 2-10 km. One popular hypothesis is that these sandbanks are generated by a 'tidal stirring' mechanism in which the inward-directed pressure gradient associated with these residual eddies produces an...
Authors
Richard P. Signell, Courtney K. Harris
Circulation and sediment transport in the vicinity of the Hudson Shelf Valley Circulation and sediment transport in the vicinity of the Hudson Shelf Valley
Sediment transport in the Hudson Shelf Valley and on the adjacent Long Island Shelf are evaluated using available data along with a three-dimensional wind-driven circulation model and a one-dimensional sediment transport model. Winds from the northwest drive currents up the Hudson Shelf Valley, while winds from the east produce weaker currents directed down the valley. Consistent with...
Authors
Courtney K. Harris, Richard P. Signell
Seafloor environments in the Long Island Sound estuarine system Seafloor environments in the Long Island Sound estuarine system
Four categories of modern seafloor sedimentary environments have been identified and mapped across the large, glaciated, topographically complex Long Island Sound estuary by means of an extensive regional set of sidescan sonographs, bottom samples, and video-camera observations and supplemental marine-geologic and modeled physical-oceanographic data. (1) Environments of erosion or...
Authors
H.J. Knebel, R. P. Signell, R.R. Rendigs, L.J. Poppe, J. H. List
Construction of digital bathymetry for the Gulf of Maine Construction of digital bathymetry for the Gulf of Maine
No abstract available.
Authors
Ed T. Roworth, Rich P. Signell
Hydrodynamic forcing and sediment character in Boston Harbor Hydrodynamic forcing and sediment character in Boston Harbor
Calculated annual excess skin friction stress at various locations in Quincy Bay (outer Boston Harbor) was found to be correlated positively with sediment sand content. The correlation was optimized when a critical shear stress (??c) of 0.085 Pa was assumed for the bay. The excess shear stress was correlated negatively with sediment lead (Pb) and polychlorinated biphenyl (PCB)...
Authors
T.M. Ravens, O.S. Madsen, R. P. Signell, E.E. Adams, P.M. Gschwend
Modeling waves and circulation in Lake Pontchartrain, Louisiana Modeling waves and circulation in Lake Pontchartrain, Louisiana
The U.S. Geological Survey is conducting a study of storm-driven sediment resuspension and transport in Lake Pontchartrain, Louisiana. Two critical processes related to sediment transport in the lake are (1) the resuspension of sediments due to wind-generated storm waves and (2) the movement of resuspended material by lake currents during storm wind events. The potential for sediment...
Authors
Richard P. Signell, Jeffrey H. List
Lateral trapping of sediment in partially mixed estuary Lateral trapping of sediment in partially mixed estuary
No abstract available.
Authors
W. R. Geyer, R. P. Signell, G. C. Kineke
The wind-forced response on a buoyant coastal current: Observations of the western Gulf of Maine plume The wind-forced response on a buoyant coastal current: Observations of the western Gulf of Maine plume
The Freshwater plume in the western Gulf of Maine is being studied as part of an interdisciplinary investigation of the physical transport of a toxic alga. A field program was conducted in the springs of 1993 and 1994 to map the spatial and temporal patterns of salinity, currents and algal toxicity. The observations suggest that the plume's cross-shore structure varies markedly as a...
Authors
D.A. Fong, W.R. Geyer, R. P. Signell
Physical processes affecting the sedimentary environments of Long Island Sound Physical processes affecting the sedimentary environments of Long Island Sound
A modeling study was undertaken to simulate the bottom tidal-, wave-, and wind-driven currents in Long Island Sound in order to provide a general physical oceanographic framework for understanding the characteristics and distribution of seafloor sedimentary environments. Tidal currents are important in the funnel-shaped eastern part of the Sound, where a strong gradient of tidal-current...
Authors
R. P. Signell, H.J. Knebel, J. H. List, A.S. Farris
Effect of wave-enhanced bottom friction on storm-driven circulation in Massachusetts Bay Effect of wave-enhanced bottom friction on storm-driven circulation in Massachusetts Bay
Massachusetts Bay is a shallow (35 m average depth) semienclosed embayment, roughly 100 ?? 50 km, which opens into the Gulf of Maine at its eastern boundary. Surface waves associated with winter storm winds from the northeast cause large sediment resuspension events, and wave and circulation fields during these events have a quasi-steady response to the wind stress. Coupled wave...
Authors
R. P. Signell, J. H. List
Coupled physical-biological models for the study of harmful algal blooms Coupled physical-biological models for the study of harmful algal blooms
No abstract available.
Authors
Peter J.S. Franks, Richard P. Signell
Seafloor environments in Cape Cod Bay, a large coastal embayment Seafloor environments in Cape Cod Bay, a large coastal embayment
Cape Cod Bay is a glacial, semi-enclosed embayment that has a patchy distribution of modern seafloor sedimentary environments of erosion or nondeposition, deposition, and sediment reworking. Sidescan-sonar records and supplemental bathymetric, sedimentary, subbottom, and physical-oceanographic data indicate that the characteristics and distribution of these three categories of bottom...
Authors
H.J. Knebel, R.R. Rendigs, J. H. List, Richard P. Signell