P. Soupy Dalyander
Joseph W. Long
Nathaniel G. Plant
David M. Thompson
2012
Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance: Locations of convergences in the maximum alongshore current
1.0
vector digital data
U.S. Geological Survey Open-File Report
2012-1234
St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL
U.S. Geological Survey, Coastal and Marine Geology Program
https://pubs.usgs.gov/of/2012/1234/datafiles.html
Nathaniel G. Plant
Joseph W. Long
P.Soupy Dalyander
David M. Thompson
2012
Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance
1.0
U.S. Geological Survey Open-File Report
2012-1234
St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL
U.S. Geological Survey, Coastal and Marine Geology Program
https://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 locations of convergences in the maximum (in terms of absolute value) alongshore current in the shallow northern Gulf of Mexico (Alabama and portion of the Florida coast) for a single set of wave conditions. Convergences are locations where the flow from both east and west is directed toward the point, e.g., positive (eastward) flow to the west and negative (westward) flow to the east. This output is based on numerical model output of wave and circulation patterns for a given wave height scenario, corresponding to a particular set of offshore wave conditions at NOAA NDBC buoy 42040. The specific wave conditions for a given layer are indicated by the file name (of format Hh_Dd_conv), also found in the shapefile attributes, and may be found by comparing the scenario name (Hh_Dd) to the look-up table included in the GIS zip file, wave_scenarios.txt. This data layer is intended to show patterns in alongshore current for intended use by individuals in SRB mitigation attempting to explain redistribution of SRBs under specific wave conditions.
This data layer is a subset of USGS Open-File Report 2012-1234, Hydrodynamic and Sediment Transport Model Application for OSAT3 Guidance. It is part of a set of data layers describing convergences in the maximum (in terms of absolute value) alongshore current for a range of wave climate scenarios. The specific wave conditions and object parameters for this layer are indicated by the file name (of format Hh_Dd_conv), and in the shapefile attributes, and may be found by comparing the scenario name (Hh_Dd) to the look-up table included in the GIS zip file, wave_scenarios.txt. NOTE: Scenarios H3_D6, H4_D5, H4_D12, H4_D13, H5_D4, H5_D5, and H5_D12 do not have convergences, and no GIS files exist in for these cases.
20100401
20120801
ground condition
As needed
-88.504638
-85.560731
30.390730
30.017758
USGS Metadata Identifier
USGS:0ba36411-ccc6-44d1-b60e-00645ff5c495
None
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
convergences
gradients
oceans and estuaries
oceans and coastal
ISO 19115 Topic Category
oceans
environment
geoscientificInformation
Data Categories for Marine Planning
predictions
physical/chemical features
Marine Realms Information Bank (MRIB) Keywords
coastal processes
numerical modeling
pollution
petroleum spills
USGS Thesaurus
coastal processes
contaminant transport
industrial pollution
mathematical modeling
ocean processes
petroleum
Geographic Names Information System
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
None
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 convergences in the maximum (in terms of absolute value) alongshore current velocity in the surf zone for Hh_Dd, characteristics of which may be found in the included wave_scenarios.txt file. Statistical values will vary if a different numerical model is used to estimate the waves and circulation.
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 for a particular scenario (Hh_Dd), the characteristics of which may be found in the included wave_scenarios.txt file. NOTE: Scenarios H3_D6, H4_D5, H4_D12, H4_D13, H5_D4, H5_D5, and H5_D12 do not have convergences, and no GIS files exist in for these cases.The convergences of the maximum (in terms of absolute value) alongshore current in the surf zone were 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.
Numerical models are used in estimating alongshore currents 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.
The D-Flow and D-Waves components of the Deltares Delft3D numerical model suite (version 4.00.01) were used to estimate east and north components of wind and wave-driven velocity for the offshore wave conditions corresponding this scenario Hh_Dd (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). 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
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
The maximum (in terms of magnitude) alongshore current within the surf zone at each alongshore location was
computed in Mathworks MATLAB v2012A using modeled flow velocities. The alongshore variant maximum velocity vector was then smoothed with a 2-km Hanning window filter to remove small-scale variations likely caused by model noise.
DELFT3D
SURFZONE
2012
CURRENT
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, locations of convergences in the maximum alongshore current are computed by finding adjacent grid cells where the current velocity transitions from eastward-directed (positive alongshore velocity) to westward-directed (negative alongshore velocity). The convergence is always selected as the negative velocity cell.
CURRENT
2012
CONVERGE
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
Export the values for each alongshore location from MATLAB format into an ArcGIS point shapefile using the Mathworks MATLAB Mapping Toolbox (v2012A). The latitude and longitude coordinates correspond to the identified shoreline location for each alongshore location. A single "converge" attribute is given a value of one; all latitute and longitude points in the file are convergence locations. 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.
CONVERGE
2012
P. Soupy Dalyander
U.S. Geological Survey
Oceanographer
mailing and physical address
384 Woods Hole Road
Woods Hole
MA
02540
USA
(508) 548-8700 x2290
(508) 457-2310
sdalyander@usgs.gov
Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog.
20170313
U.S. Geological Survey
Alan O. Allwardt
Contractor -- Information Specialist
mailing and physical address
2885 Mission Street
Santa Cruz
CA
95060
831-460-7551
831-427-4748
aallwardt@usgs.gov
Keywords section of metadata optimized by correcting variations of theme keyword thesauri and updating/adding keywords.
20180329
U.S. Geological Survey
Arnell S. Forde
Geologist
mailing and physical address
600 4th Street South
St. Petersburg
FL
33701
727-502-8000
aforde@usgs.gov
Added keywords section with USGS persistent identifier as theme keyword.
20201013
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Gulf of Mexico
Vector
Entity point
6
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
Hh_Dd_conv
Locations of convergences in the maximum alongshore current for specific wave scenarios
USGS
FID
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
Shape
Feature geometry.
ESRI
Coordinates defining the features.
Scenario_H
Scenario wave height number (e.g., "h" in Hh_Dd, see wave_scenarios.txt)
USGS
1
5
non-dimensional
1
Scenario_D
Scenario wave direction number (e.g., "d" in Hh_Dd, see wave_scenarios.txt)
USGS
1
16
non-dimensional
1
converge
All of the latitude and longitude points in this layer are convergences, indicated by a value of one in this attribute.
USGS
1
1
non-dimensional
1
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
Hh_Dd_conv.shp: locations of convergences for the Hh_Dd scenario. NOTE: Specific layer name indicates the scenario (Hh_Dd), with characteristics given in the included wave_scenarios.txt file.
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
0.500
https://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.
20201013
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
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
local time
None
None