P. Soupy Dalyander
Joseph W. Long
Nathaniel G. Plant
David Thompson
2012
Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance: Surf-zone integrated alongshore potential flux for oil-sand balls of varying sizes weighted by probability of wave scenario occurrence
1.0
vector digital data
Open-File Report (OFR)
2012-1234
St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL
U.S. Geological Survey, Coastal and Marine Geology Program
http://pubs.usgs.gov/of/2012/1234/datafiles.html
Nathaniel G. Plant
Joseph W. Long
P.Soupy Dalyander
David Thompson
2012
Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance
1.0
Open-File Report (OFR)
2012-1234
St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL
U.S. Geological Survey, Coastal and Marine Geology Program
http://pubs.usgs.gov/of/2012/1234/
The U.S. Geological Survey has developed a method for estimating the mobility and potential alongshore transport of heavier-than-water sand and oil agglomerates (tarballs or surface residual balls, SRBs). During the Deepwater Horizon spill, some oil that reached the surf zone of the northern Gulf of Mexico mixed with suspended sediment and sank to form sub-tidal mats. If not removed, these mats can break apart to form SRBs and subsequently re-oil the beach. A method was developed for estimating SRB mobilization and alongshore movement. A representative suite of wave conditions was identified from buoy data for April, 2010, until August, 2012, and used to drive a numerical model of the spatially-variant alongshore currents. Potential mobilization of SRBs was estimated by comparing combined wave- and current-induced shear stress from the model to critical stress values for several sized SRBs. Potential alongshore flux of SRBs was also estimated to identify regions more or less likely to have SRBs deposited under each scenario. This methodology was developed to explain SRB movement and redistribution in the alongshore, interpret observed re-oiling events, and thus inform re-oiling mitigation efforts.
This GIS layer contains an estimate of the average surf-zone integrated alongshore potential flux (in kg/s) of various size surface residual balls (SRBs) in the shallow northern Gulf of Mexico (Alabama and portion of the Florida coast) for the time period of 04/01/2010 to 08/01/2012. This output is based on numerical model output of wave and circulation patterns for a set of 80 wave height scenarios, each corresponding to a particular set of offshore wave conditions at NOAA NDBC buoy 42040. The wave and wind conditions at the buoy each hour over the time period of interest have been identified as most closely corresponding to 1 of these 80 conditions, and a probability of occurrence assigned to each scenario based on the percentage of observations assigned to that scenario (see included wave_scenarios.txt). This layer contains the weighted average of the surf-zone integrated alongshore potential flux (smoothed over 2 km to reduce model noise) for each of those scenarios. This value is an estimate of the total alongshore flux in the surf zone at each alongshore location, assuming the entire seafloor was covered with SRBs of the given size and density. Because the seafloor is not covered in SRBs, this potential flux identifies patterns in transport and does quantify the actual flux at any given location or time. Characteristics of SRB classes may be found in the look-up table included in the GIS zip file, SRB_casses.txt. This data layer is intended to show patterns in transport (convergences, divergences, and gradients) for intended use by individuals in SRB mitigation attempting to explain redistribution of SRBs over this time period.
This data layer is a subset of USGS Open-File Report 2012-1234, Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance. It is a weighted average of surf-zone integrated alongshore potential flux for various size SRBs based on probability of occurrence during the period of 04/01/2010 to 08/01/2012 for a range of wave climate scenarios. The results for each individual scenario that form the basis of this weighted averaged may be found within the report, naming convention Hh_Dd_potential_flux, where Hh_Dd indicates the specific scenario (see wave_scenarios.txt). SRB class properties may be found in the look-up table included in the GIS zip file, SRB_casses.txt.
20100401
20120801
ground condition
As needed
-88.712143
-85.506075
30.396484
29.970005
General
bottom shear stress
U.S. Geological Survey
USGS
Woods Hole Coastal and Marine Science Center
WHCMSC
Coastal and Marine Geology Program
CMGP
wave
current
Delft3D
St. Petersburg Coastal and Marine Science Center
SPCMSC
tarballs
surface residual balls
SRBs
sediment mobility
surf zone
alongshore currents
wave-driven currents
ISO 9115 Topic Category
oceans
oceans and estuaries
oceans and coastal
geoscientificInformation
General
Gulf of Mexico
Florida
Alabama
United States
North America
Atlantic Ocean
Mobile Bay
Pensacola Bay
Choctawhatchee Bay
Santa Rosa
Fort Pickens
Gulf Shores
Panama City
Little Lagoon
General
seafloor
None
Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset.
P. Soupy Dalyander
U.S. Geological Survey
Oceanographer
mailing and physical address
384 Woods Hole Road
Woods Hole
MA
02543-1598
USA
(508) 548-8700 x2290
(508) 457-2310
sdalyander@usgs.gov
model_bathymetry.jpg
Graphic showing the numerical model domain over which analysis is conducted.
JPEG
Microsoft Windows Vista Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 9.3.1.4095
The attributes in this data layer correspond to an average of surf-zone integrated alongshore potential flux for 80 individual representative wave scenarios, weighted by probability of occurrence over the time period of 04/01/2010 to 08/01/2012, for various classes of SRBs, the characteristics of which may be found in the included SRB_classes.txt file. The potential flux was calculated from wave and current estimates generated with Delft3D, and would vary if different models were used or if different model inputs (such as bathymetry, forcing winds, and boundary conditions) or parameterizations were chosen. Potential flux estimates would vary for different size or density SRBs and/or if a different formulation for calculating the flux is used. Potential flux estimates would also vary if a different set of wave scenarios (see wave_scenarios.txt) were used to represent the time frame of interest, or if a different time period of interest was examined. The quantitative value calculated assumes the entire seafloor is covered with SRBs of the given size and density; since this is not the case, the output provides patterns in transport for use in identifying likely areas of deposition and is not quantitatively meaningful in terms of actual flux at any point in time or space.
No duplicate features are present. All polygons are closed, and all lines intersect where intended. No undershoots or overshoots are present.
All model output values were used in the calculation of this statistic. The statistic was calculated as an average of surf-zone integrated alongshore potential flux for 80 individual representative wave scenarios, weighted by probability of occurrence over the time period of 04/01/2010 to 08/01/2012, for various classes of SRBs, the characteristics of which may be found in the included SRB_classes.txt file. The potential flux was calculated from wave and current estimates generated with Delft3D, and would vary if different models were used or if different model inputs (such as bathymetry, forcing winds, and boundary conditions) or parameterizations were chosen. Potential flux estimates would vary for different size or density SRBs and/or if a different formulation for calculating flux is used. Potential flux estimates would also vary if a different set of wave scenarios (see wave_scenarios.txt) were used to represent the time frame of interest, or if a different time period of interest was examined.
Numerical models are used in the generation of hydrodynamic conditions used in creating this data layer. Because the overall horizontal accuracy of the data set depends on the accuracy of the model, the underlying bathymetry, forcing values used, and so forth, the spatial accuracy of this data layer cannot be meaningfully quantified.
NOAA National Centers for Environmental Prediction (NCEP)
20110601
NOAA/NCEP Global Forecast System (GFS) Atmospheric Model
Camp Springs, MD
NOAA National Centers for Environmental Prediction
http://nomads.ncdc.noaa.gov/data.php
online
20100401
20120531
publication date
NOAA GFS
Wind speed data at 10 m above the sea surface from the NOAA Global Forecast System (GFS) 0.5 degree model is interpolated by NOAA to the 4' Wavewatch3 grid and archived. These archived data are used to drive the numerical wave and circulation model that creates estimated of bottom shear stress.
NOAA National Centers for Environmental Prediction (NCEP
20121001
NOAA/NWS/NCEP 4' Wavewatch III Operational Wave Forecast
Camp Springs, MD
NOAA National Centers for Environmental Prediction
http://polar.ncep.noaa.gov/waves/index2.shtml
online
20100401
20120531
publication date
NOAA WW3
Boundary conditions for the wave model were provided by the 4' NOAA/NWS/NCEP Wavewatch III operational ocean wave forecast.
National Data Buoy Center
20120901
National Data Buoy Center Buoy 42040
Stennis Space Center, MS
National Oceanic and Atmospheric Administration
http://www.ndbc.noaa.gov/station_page.php?station=42040
online
20100401
20120801
publication date
NDBC42040
Observational wave data from NDBC Buoy 42040 were used to identify the percentage of observations between 04/01/2010 and 08/01/2012 which corresponded to each of 80 wave scenarios distinguished by wave height and direction, and to identify a characteristic time period in the record for each scenario.
Using observed wave conditions from NOAA buoy 42040 and Mathworks MATLAB software 2012A, the hourly wave buoy observations between 04/01/2010 and 08/01/2012 were each classified as falling into 1 of 80 wave scenarios defined by wave height and direction. For each scenario, a specific time step was identified in the record which was most representative of the other observations within the same wave height and direction bins based on both wave (height, period, and direction) and wind (speed and direction) characteristics. The characteristics of these scenarios, along with the percentage of observation in the record and the chosen representative time period, may be found in wave_scenarios.txt. The probability of occurrence for each wave scenario along with its characteristics and representative time periods were saved in MATLAB .mat format.
NDBC42040
2012
WAVE_SCENARIOS
Nathaniel Plant
USGS
Oceanographer
mailing and physical address
600 4th Street S
St. Petersburg
FL
33701
(727) 803-8747 x3072
(727) 803-2023
nplant@usgs.gov
The D-Flow and D-Waves components of the Deltares Delft3D numerical model suite (version 4.00.01) were used to estimate bottom orbital velocity, peak period, peak wave direction, and east and north components of wind and wave-driven velocity for the offshore wave conditions corresponding to each scenario's representative time period (characteristics of which may be found in the included wave_scenarios.txt file) in each grid cell in the model domain. The wave model D-Waves, based on the Simulating WAves Nearshore (SWAN) model, is a 3rd generation phase-averaged numerical wave model which conserves wave energy subject to generation, dissipation, and transformation processes and resolves spectral energy density over a range of user-specified frequencies and directions. D-Wave was used in stationary mode. D-Flow solves the shallow water Navier Stokes equations and is run in 2-D depth-averaged mode, with linkage to D-Waves allowing the generation of wave-driven currents via wave radiation stress forcing. Default values for model parameters governing horizontal viscosity, bottom roughness, and wind drag were used. Neumann boundary conditions were used along the east, west, and south model boundaries with harmonic forcing set to zero. Model bathymetry was provided by the NOAA National Geophysical Data Center Northern Gulf Coast digital elevation map, referenced to NAVD88.
Significant wave height, dominant wave period, and wave direction were prescribed as D-Wave TPAR format files every 30 grid cells along the model boundary using results from the NOAA Wavewatch III 4' multi-grid model for a representative moment in time corresponding to the offshore wave conditions of the scenario, the specific time of which may be found in the included wave_scenarios.txt file. A JONSWAP (JOint NOrth Sea WAve Project) spectral shape was assumed at these boundary points. Wind forcing was provided using the archived WavewatchIII 4' winds, extracted from the NOAA GFS wind model, for this time. The D-Wave directional space covers a full circle with a resolution was 5 degrees (72 bins). The frequency range was specified as 0.05-1 Hz with logarithmic spacing. Bottom friction calculations used the JONSWAP formulation with a uniform roughness coefficient of 0.067 m2/s3. 3rd-generation physics are activated which accounts for wind wave generation, triad wave interactions and whitecapping (via the Komen et al parameterization). Depth-induced wave breaking dissipation is included using the method of Battjes and Janssen with default values for alpha (1) and gamma (0.73). Wave model outputs of bottom orbital velocity, peak period, and peak wave direction were extracted on the wave model grid, and current model outputs of east and north current velocity component were extracted and interpolated to the wave model grid (staggered points in relation to the current model grid).
NDBC observations from station 42012 for the representative scenario time periods were used to validate the wave model results.
NOAA GFS
NOAA WW3
WAVE_SCENARIOS
2012
DELFT3D
Joseph W. Long
U.S. Geological Survey
Oceanographer
mailing and physical address
600 4th Street S
St. Petersburg
FL
33701
USA
(727) 803-8747 x3024
(727) 803-2032
jwlong@usgs.gov
Identify the spatial extent of the surf zone at each alongshore location using Mathworks MATLAB software (v2012A). The shoreline is identified from the gridded bathymetry as the cross-shore grid cell of minimum water depth at each alongshore transect. In areas where lagoons separate barrier islands and the mainland coast, the shoreline is considered along the seaward side of the barrier island only. The shoreline is not continuous due to interruptions at inlets. For each alongshore transect, the surf zone is defined as the area between the shoreline and the location of maximum wave height (found in a search area extending from the shoreline to the most offshore point of modeled depth-induced wave breaking dissipation). The extent of the surf zone (as indices into the grid at each alongshore location of the cross-shore position of the shoreline and seaward edge of the surf zone) was saved for all of the scenarios into a MATLAB .mat structure.
DELFT3D
2012
SURFZONE
David Thompson
U.S. Geological Survey
Oceanographer
mailing and physical address
600 4th Street S
St. Petersburg
FL
33701
USA
(727) 803-8747 x3079
(727) 803-2032
dthompson@usgs.gov
For each scenario, estimate the spatially variant potential flux for each SRB size class, characteristics of which may be found in the included SRB_classes.txt file. Calculations are performed in Mathworks MATLAB (v2012A). Potential flux is calculated for model output values (wave orbital velocity, peak period, and direction; depth-averaged current magnitude and direction; total water level from the model and bathymetry) using the Shield's parameter following the Soulsby-van Rijn approach described in Soulsby (1997). The direction of transport is identified is either positive (to the east) or negative (to the west) from the sign of the alongshore component of velocity (output u1 from the numerical model). The Shield's parameter is identified as a "high" critical stress value, corresponding to instances when an SRB of the identified size is within a uniform bed of similarly sized SRBs. Exposure above the bed, such as may occur with a single SRB on a sand band, reduces the critical shear stress value for incipient motion. Based on field observations of gravel and sand mixtures, a "medium" critical stress value is calculated from a constant non-dimensional Shields parameter of 0.02, and a "low" critical stress value is calculated from a constant non-dimensional Shields parameter of 0.01 (Andrews, 1983; Bottacin-Busolin et al, 2008; Fenton and Abbott, 1977; Wiberg and Smith, 1987; Wilcock, 1998). Each of these three threshold values are saved in MATLAB .mat format.
The same individual who completed this processing step completed all additional processing steps.
References:
Andrews, E.D. (1983). Entrainment of gravel from naturally sorted riverbed material. Geo. Soc. Amer. Bull. (94), 1225-1231.
Bottacin-Busolin, A., Tait, S.J., Marion, A., Chegini, A., Tregnaghi, M. (2008). Probabilistic description of grain resistance from simultaneous flow field and grain motion measurements. Water Resources Res. (44), WO9419.
Fenton, J.D., Abbott, J.E. (1977). Initial movement of grains on a stream bed: the effect of relative protusion. Proc. R. Soc. Lond. A. (352), 523-537.
Soulsby, R., 1997. Dynamics of Marine Sands, a Manual for Practical Applications. Thomas Telford Publications, London.
Wibert, P.L., Smith, J.D. (1987). Calculations of the Critical Shear Stress for Motion of Uniform and Heterogenous Sediments. Water Resources Res. (23), 1471-1480.
Wilcock, P.R. (1998). Two-Fraction Model of Initial Sediment Motion in Gravel-Bed Rivers. Science (280), 410-412.
DELFT3D
2012
FLUX2D
P. Soupy Dalyander
U.S. Geological Survey
Oceanographer
mailing and physical address
384 Woods Hole Road
Woods Hole
MA
02543
(508) 548-8700 x2290
(508) 457-2310
sdalyander@usgs.gov
For each scenario, integrate the alongshore potential flux at each alongshore location over the cross-shore region identified as surf zone in the previous processing step for this scenario. The 2D potential flux (in m3/m/s) is multiplied times the cross-shore width of each grid cell (in m, corresponding to half the distance from each grid cell to the grid cell to the north plus half the distance from the grid cell to the grid cell to the south) to obtain the flux (in m3/s) at that grid cell. This value is then summed over all of the cross-shore locations at that alongshore location and multiplied by SRB density (2107 kg/m3) to obtain the surf-zone integrated alongshore potential flux (in kg/s) at each alongshore location. The surf-zone integrated alongshore potential flux is then smoothed with a 2-km Hanning window filter to remove small-scale structure likely associated with model noise. These values are saved in Matlab .mat format.
FLUX2D
SURFZONE
2012
FLUX1D
For each grid cell, calculate the average surf-zone integrated alongshore potential flux from the surf-zone integrated alongshore potential flux for each scenario, weighted by the percent observation of that scenario in the time period of 04/01/2010 to 08/01/2012 (see wave_scenarios.txt).
WAVE_SCENARIOS
FLUX1D
2012
AVG_FLUX
Exported the values for each alongshore point from MATLAB format into an ArcGIS shapefile using the Mathworks MATLAB Mapping Toolbox (v2012A). The shapefile is written with the "shapewrite" command. Because MATLAB does not assign a projection, the projection corresponding to the projection associated with the bathymetry used in the numerical models is added in ArcCatalog 9.3. The file was then quality checked in ArcMap to insure values were properly exported to the shapefile from MATLAB.
AVG_FLUX
2012
Gulf of Mexico
Vector
Entity point
993
0.000001
0.000001
Decimal degrees
D_WGS_1984
WGS_1984
6378137.000000
298.257224
North American Vertical Datum of 1988
0.01 m
meters
Explicit elevation coordinate included with horizontal coordinates
Weighted_potential_flux
Surf-zone integrated alongshore potential flux for oil-sand balls of varying sizes weighted by probability of wave scenario occurrence
USGS
FID
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
Shape
Feature geometry.
ESRI
Coordinates defining the features.
SRB1_high
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 1 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relative high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB1_med
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 1 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB1_low
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 1 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB2_high
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 2 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relative high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB2_med
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 2 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB2_low
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 2 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB3_high
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 3 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relative high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB3_med
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 3 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB3_low
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 3 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB4_high
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 4 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relative high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB4_med
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 4 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB4_low
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 4 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB5_high
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 5 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relative high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB5_med
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 5 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB5_low
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 5 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB6_high
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 6 (see SRB_classes.txt) calculated from the Shield's parameter. The Shield's parameter is a relative high critical stress estimate and does not account for a reduced critical stress due to potential SRB exposure above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB6_med
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 6 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.02. This critical stress estimate is a mid-range value accounting for a reduced critical stress due to some exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
SRB6_low
Surf-zone integrated alongshore potential flux (in kg/s) as an average weighted by percent occurrence in the time period of 04/01/2010 to 08/01/2012 of surf-zone integrated alongshore potential flux for 80 wave scenarios (see wave_scenarios.txt) using a critical stress for SRB class 6 (see SRB_classes.txt) calculated from a non-dimensional Shield's parameter of 0.01. This critical stress estimate is a low value accounting for a reduced critical stress due to exposure of the SRB above the seafloor.
USGS
-1000
1000
kg/s
0.000001
P. Soupy Dalyander
U.S. Geological Survey
Oceanographer
mailing and physical address
384 Woods Hole Road
Woods Hole
MA
02543-1598
USA
(508) 548-8700 x2290
(508) 457-2310
sdalyander@usgs.gov
Weighted_potential_flux.shp: average surf-zone integrated alognshore potential flux for various size SRBs (see SRB_classes.txt) for the time period of 04/01/2010 to 08/01/2012.
Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
SHP
3.3
ESRI shapefile
WinZip archive file containing the shapefile components. The WinZip file also includes FGDC compliant metadata.
WinZip 12.0 archive
495 KB
http://pubs.usgs.gov/of/2012/1234/datafiles.html
None
These data are available in Environmental Systems Research Institute (ESRI) shapefile format. The user must have ArcGIS or ArcView 3.0 or greater software to read and process the data file. In lieu of ArcView or ArcGIS, the user may utilize another GIS application package capable of importing the data. A free data viewer, ArcExplorer, capable of displaying the data is available from ESRI at www.esri.com.
20121112
U.S. Geological Survey
P. Soupy Dalyander
Oceanographer
mailing and physical address
384 Woods Hole Role
Woods Hole
MA
02543-1598
USA
(508) 548-8700 x2290
(508) 457-2310
sdalyander@usgs.gov
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
local time
None
None
http://www.esri.com/metadata/esriprof80.html
ESRI Metadata Profile