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 the date range of May, 2010 to May, 2011, and would potentially vary somewhat if performed on a different time period. The underlying time-series of bottom shear stress was calculated from wave and current estimates generated with numerical models, and would vary if different models are used or if different model inputs (such as bathymetry or forcing winds) or parameterizations were chosen.
Source_Information:
Source_Citation:
Citation_Information:
Originator: NOAA National Centers for Environmental Prediction (NCEP)
Publication_Date: 20110601
Title: NOAA/NCEP Global Forecast System (GFS) Atmospheric Model
Publication_Information:
Publication_Place: Camp Springs, MD
Publisher: NOAA National Centers for Environmental Prediction
Online_Linkage: http://nomads.ncdc.noaa.gov/data.php
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20100401
Ending_Date: 20110601
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: NOAA GFS
Source_Contribution:
The NOAA Global Forecast System (GFS) 0.5 degree model was used to provide wind speed data at 10 m above the sea surface to drive the numerical wave model used to generate bottom orbital wave velocities for calculations of a time-series of bottom shear stress.
Source_Information:
Source_Citation:
Citation_Information:
Originator: NOAA National Centers for Environmental Prediction (NCEP)
Publication_Date: 20110601
Title: NOAA/NCEP North American Mesoscale (NAM) Atmospheric Model
Publication_Information:
Publication_Place: Camp Springs, MD
Publisher: NOAA National Centers for Environmental Prediction
Online_Linkage: http://nomads.ncdc.noaa.gov/data.php
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20100401
Ending_Date: 20110601
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: NOAA NAM
Source_Contribution:
The NOAA North American Mesoscale (NAM) model was used to provide wind speed data at 10 m above the sea surface to drive the numerical wave model used to generate bottom orbital wave velocities for calculations of a time-series of bottom shear stress.
Source_Information:
Source_Citation:
Citation_Information:
Originator: University of Massachusetts, Dartmouth
Publication_Date: 2014
Title: Finite Volume Coastal Ocean Model, Gulf of Maine (FVCOM-GOM)
Publication_Information:
Publication_Place: Dartmouth, MA
Publisher: University of Massachusetts, Dartmouth
Online_Linkage: http://fvcom.smast.umassd.edu/research_projects/GB/grid_g3.html
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20100501
Ending_Date: 20110501
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: FVCOM
Source_Contribution:
The University of Massachusetts at Dartmouth (UMASSD) FVCOM model archived forecast was used to provide estimates of near-bed current velocity used for calculating the time-series of bottom shear stress.
The FVCOM-GOM hydrodynamic model (
http://fvcom.smast.umassd.edu/research_projects/GB/index.html) is a sub-model of the Northeast Coastal Ocean Forecast System (NECOFS), operated by UMASSD. This quasi-operational nowcast/forecast system is an element of the Northeastern Regional Association of Coastal Observing Systems (NERACOOS,
http://neracoos.org/), part of the U.S. Integrated Ocean Observing System (
http://www.ioos.noaa.gov/). The underlying circulation model is the Finite Volume Coastal Ocean Model (FVCOM), a finite-element, unstructured grid, primitive equation ocean model that solves for the free surface elevation and three dimensional flow patterns, temperature, and salinity.
The FVCOM-GOM configuration has varying horizontal resolution (0.3-15 km) and 40 layers in vertical terrain-following coordinates. Ocean open boundary values are from a global forecast that uses the HYbrid Coordinate Ocean Model (HyCOM) with assimilation of satellite and in situ data with the Navy Coupled Ocean Data Assimilation (NCODA) system. Tidal harmonic boundary variability is determined from a regional tidal model.
The data files for the time period used in this analysis were acquired from an archived data set available online at
http://www.smast.umassd.edu:8080/thredds/catalog.html.
Source_Information:
Source_Citation:
Citation_Information:
Originator: NOAA National Centers for Environmental Prediction (NCEP
Publication_Date: 20110601
Title: NOAA/NWS/NCEP Global Wavewatch III Operational Wave Forecast
Publication_Information:
Publication_Place: Camp Springs, MD
Publisher: NOAA National Centers for Environmental Prediction
Online_Linkage: http://polar.ncep.noaa.gov/waves/index2.shtml
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20100401
Ending_Date: 20110601
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: NOAA WW3
Source_Contribution:
Boundary conditions for the wave model were provided by the global NOAA/NWS/NCEP Wavewatch III operational ocean wave forecast.
Process_Step:
Process_Description:
The WavewatchIII (WW3) numerical wave model (v3.14) was run on both a global 30' and regional North Atlantic 10' grid. The global grid is identical to the one used by the NOAA WW3 forecast system, whereas the regional grid is based on the NOAA WW3 grid but was modified slightly to remove parts of the "do not compute" mask at the outer boundaries where output was needed to pass to the nested, higher resolution grid. WW3 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. The model was identically configured to the multi-grid system set-up used by the NOAA WW3 operational forecast (more information at
http://polar.ncep.noaa.gov/waves/index2.shtml), and was rerun purely to generate full spectra boundary conditions at the boundaries of the higher resolution nested domain. Wind forcing was provided at 3-hour resolution from the NOAA North American Mesoscale (NAM) model (12 km resolution) over its domain, with the rest of the domain (outside the NAM grid) provided by the NOAA Global Forecasting System (GFS) model at 0.5 degree resolution.
Source_Used_Citation_Abbreviation: NOAA GFS
Source_Used_Citation_Abbreviation: NOAA NAM
Source_Used_Citation_Abbreviation: NOAA WW3
Process_Date: 2012
Source_Produced_Citation_Abbreviation: WW3
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: P. Soupy Dalyander
Contact_Organization: U.S. Geological Survey
Contact_Position: Oceanographer
Contact_Address:
Address_Type: mailing and physical address
Address: 600 Fourth Street S
City: St Petersburg
State_or_Province: FL
Postal_Code: 33701
Country: USA
Contact_Voice_Telephone: (727) 502-8000 x8124
Contact_Facsimile_Telephone: (727) 502-8001
Contact_Electronic_Mail_Address: sdalyander@usgs.gov
Process_Step:
Process_Description:
The Simulating WAves Nearshore (SWAN) numerical wave model (version 40.81, modified for proper calculation of RMS bottom orbital velocity and for output of bottom wave direction) was used to create a time-series of bottom orbital velocity, bottom representative period, and bottom wave direction over the one year time period of May, 2010 - May, 2011 in each grid cell in the model domain. The wave model SWAN 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. Although stress calculations were only performed over the spatial extent of the hydrodynamic model, SWAN was run over a larger spatial scale. The model domain consists of seven overlapping regular numerical model grids that follow the eastern and Gulf of Mexico coasts of the United States at approximately 3.5 km resolution. The model was run for April 2010 using the default SWAN initial condition formulation for a non-stationary run, e.g., a JONSWAP spectrum from prescribed initial wind conditions, to develop initial conditions for the one year study period (May 2010 to May 2011).
Full spectra boundary conditions at each model ocean boundary point are interpolated from the output of the regional 10' Wavewatch III model, updated every hour. Wind forcing was provided at 3-hour resolution from the NOAA North American Mesoscale (NAM) model (12 km resolution) over its domain, with forcing at the most offshore portions of the grid (outside the NAM grid) provided by the NOAA Global Forecasting System (GFS) model at 0.5 degree resolution. The SWAN directional resolution was 6 degrees (60 bins), determined via sensitivity analysis as the coarsest (and hence least computationally expensive) resolution that does not result in the "Garden-Sprinkler Effect" (GSE), wherein swell traveling over large distances inaccurately disintegrates into non-continuous wave fields as a result of frequency and directional discretization. The minimum frequency bin should be set to a value less than 0.7 times the lowest expected peak frequency and the maximum frequency bin should be set at least 2.5-3 times the highest expected peak frequency expected. In order to determine appropriate values, the peak periods from 43 NDBC buoys throughout the wave model domain were analyzed (when available) over the one year period of the study, yielding 297,533 hourly observations. The 99th and 1st percentiles of peak period were 15 s and 3 s, corresponding to frequencies of 0.07 Hz and 0.33 Hz, noting that these values may be biased by buoy limits of detection at high and low frequencies. The frequency range was therefore specified as 0.04-1 Hz. SWAN was allowed to internally determine the frequency resolution as one tenth of each frequency bin for best performance of the discrete interaction approximation (DIA) method of nonlinear 4-wave interactions, resulting in 34 frequency bins. Bottom friction calculations used the Madsen formulation with a uniform roughness length scale of 0.05 m. This value was selected for the best comparison of model output and buoy observations within the domain, and does not correspond to physical roughness values or the bottom roughness used in stress calculations. Wind generation and whitecapping parameterizations follow the modified Komen approach prescribed by Rogers et al. (2003), which reduces inaccurate attenuation of swell energy by whitecapping. Wave model outputs of bottom orbital velocity, bottom representative period, and bottom wave direction were output hourly and interpolated onto the SABGOM model grid.
The same person that conducted this processing step conducted each subsequent processing step.
References:
Rogers, W.E., Hwang, P.A., Wang, D.W., 2003. Investigation of Wave Growth and Decay in the SWAN Model: Three Regional-Scale Applications. J. Phys. Oceanogr. 33, 366-389.
Source_Used_Citation_Abbreviation: NOAA GFS
Source_Used_Citation_Abbreviation: NOAA NAM
Source_Used_Citation_Abbreviation: WW3
Process_Date: 2012
Source_Produced_Citation_Abbreviation: SWAN WEST ATL
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: P. Soupy Dalyander
Contact_Organization: U.S. Geological Survey
Contact_Position: Oceanographer
Contact_Address:
Address_Type: mailing and physical address
Address: 600 Fourth Street S
City: St Petersburg
State_or_Province: FL
Postal_Code: 33701
Country: USA
Contact_Voice_Telephone: (727) 502-8000 x8124
Contact_Facsimile_Telephone: (727) 502-8001
Contact_Electronic_Mail_Address: sdalyander@usgs.gov
Process_Step:
Process_Description:
Use the wave model and current model results to calculate the time series of bottom shear stress within each wave model grid cell using Mathworks MATLAB software (v2011A). Bottom shear stress estimates are made following Grant-Madsen (GM) (Madsen, 1994), from the estimated bottom orbital velocities and bottom wave periods generated with SWAN, and near-bed current estimates from the FVCOM-GOM hydrodynamic model. The GM approach relies on an eddy viscosity turbulence closure model and formulates the wave stress, current stress, and combined wave-current bottom stress as functions of a representative bottom wave orbital velocity, representative bottom wave period, current flow at some reference height, the angle between wave and current propagation, and bottom roughness. Full details of the GM formulation may be found elsewhere (Glenn, 1983; Glenn and Grant, 1987; Grant and Madsen, 1979, 1982, 1986; Madsen, 1994; Madsen et al., 1988).
Wave direction, bottom orbital velocities, and bottom periods are calculated internally by the wave model. Near-bed current magnitude and direction are taken from the hydrodynamic model, with the reference height taken as the distance from the cell vertical midpoint to the seabed. GM requires that the current velocity be taken above the wave boundary layer (WBL) but within the log-profile current velocity layer. If the thickness of the WBL calculated using GM exceeds one or more of the deepest grid cells, the current estimate and associated reference height are used from the deepest grid cell at each location where the reference height exceeds the width of the WBL. An estimate must be used for the maximum reference height where the log-profile velocity layer assumption is valid. As discussed in Grant and Madsen (1986), the thickness of the log-profile layer based on laboratory experiments is approximately 10% of the current boundary layer thickness (Clauser, 1956). Because tidal currents, storm currents, and mean flow have a boundary layer thickness on the order of magnitude 10's of meters (Goud, 1987), a maximum value for reference height is set as 5 m. The GM bottom boundary layer model also requires a value for bottom roughness; a uniform value of 0.005 m is used throughout the domain.
References:
Clauser, F.H., 1956. The turbulent boundary layer. Adv. Appl. Mech. 4, 1-51.
Madsen, O.S., 1994. Spectral wave-current bottom boundary layer flows, Proceedings 24th Conf. Coastal Eng., pp. 384-398.
Glenn, S.M., 1983. A Continental Shelf Bottom Boundary Layer Model: The Effects of Waves, Currents, and a Moveable Bed. Dissertation, Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, Cambridge, MA, 237 pp.
Glenn, S.M., Grant, W.D., 1987. A suspended sediment stratification correction for combined wave and current flows. J. Geophys. Res. 92, 8244-8264.
Goud, M.R., 1987. Prediction of Continental Shelf Sediment Transport Using a Theoretical Model of the Wave-Current Boundary Layer. Dissertation, Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, Cambridge, MA, 211 pp.
Grant, W.D., Madsen, O.S., 1986. The continental-shelf bottom boundary-layer. Annu. Rev. Fluid Mech. 18, 265-305.
Grant, W.D., Madsen, O.S., 1982. Movable bed roughness in unsteady oscillatory flow. J. Geophys. Res. 87, 469-481.
Grant, W.D., Madsen, O.S., 1979. Combined wave and current interaction with a rough bottom J. Geophys. Res. 84, 1797-1808.
Madsen, O.S., 1994. Spectral wave-current bottom boundary layer flows, Proceedings 24th Conf. Coastal Eng., pp. 384-398.
Madsen, O.S., Poon, Y., Graber, H.C., 1988. Spectral wave attenuation by bottom friction: theory, Proceedings 21st Int. Conf. Coast. Eng., pp. 492-504.
Source_Used_Citation_Abbreviation: SWAN WEST ATL
Source_Used_Citation_Abbreviation: FVCOM
Process_Date: 2013
Source_Produced_Citation_Abbreviation: STRESS TSERIES
Process_Step:
Process_Description:
Calculate the half interpercentile range of bottom shear stress by year and season in Mathworks MATLAB software (v2011A). This value is calculated as half of the difference between the 16th and 84th percentiles of the time series within each grid cell, and would be equal to the standard deviation of the observations followed a normal distribution. These statistical values are saved in MATLAB .mat format.
Source_Used_Citation_Abbreviation: STRESS TSERIES
Process_Date: 2013
Source_Produced_Citation_Abbreviation: HIPR STATISTIC
Process_Step:
Process_Description:
Export the values for each grid cell from MATLAB format into an ArcGIS shapefile using the Mathworks MATLAB Mapping Toolbox (v2011A). Grid cells where the height of the deepest grid cell in the circulation model is always above the maximum accepted reference height for validity of a log-profile assumption (necessary for stress calculations), as well as grid cells with depth greater than 500 m, are excluded and not exported to Arc. In some cases, data may exist during parts of the year and not others; in this case, the statistic is calculated and included for the season where model output exist, and a missing data value of -9999 (replacing the MATLAB native NaN format) is used for seasons where no valid statistic can be calculated. A geographic data structure is created in MATLAB with the following fields: Geometry ('Polygon'), Lon (the five longitude points defining each grid cell, with one of the four grid corner values repeated to close the polygon in Arc), Lat (same as Lon, for the latitude points of the grid), Year (the statistic calculated for the entire year), Winter (the statistic calculated for December, January, and February), Spring (the statistic calculated for March, April, and May), Summer (the statistic calculated for June, July, and August), and Fall (the statistic calculated for September, October, and November). The shapefile is then 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.
Source_Used_Citation_Abbreviation: HIPR STATISTIC
Process_Date: 2013
Process_Step:
Process_Description:
Process_Date: 20140606
Process_Step:
Process_Description:
Edits to the metadata were made to fix any errors that MP v 2.9.32 flagged. This is necessary to enable the metadata to be successfully harvested for various data catalogs. In some cases, this meant adding text "Information unavailable" or "Information unavailable from original metadata" for those required fields that were left blank. Other minor edits were probably performed (title, publisher, publication place, etc.). This is an online database - so the series is online database. The metadata standard requires an Issue Identification - so the database title was used. The metadata date (but not the metadata creator) was edited to reflect the date of these changes. The metadata available from a harvester may supersede metadata bundled within a download file. Compare the metadata dates to determine which metadata file is most recent.
Process_Date: 20160701
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd.
City: Woods Hole
State_or_Province: MA
Postal_Code: 02556
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog.
Process_Date: 20170313
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Alan O. Allwardt
Contact_Position: Contractor -- Information Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: 2885 Mission Street
City: Santa Cruz
State_or_Province: CA
Postal_Code: 95060
Contact_Voice_Telephone: 831-460-7551
Contact_Facsimile_Telephone: 831-427-4748
Contact_Electronic_Mail_Address: aallwardt@usgs.gov
Process_Step:
Process_Description:
Added keywords from Coastal and Marine Ecological Classification Standard (CMECS) to metadata.
Process_Date: 20180426
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Alan O. Allwardt
Contact_Position: Contractor -- Information Specialist
Contact_Address:
Address_Type: mailing and physical address
Address: 2885 Mission Street
City: Santa Cruz
State_or_Province: CA
Postal_Code: 95060
Contact_Voice_Telephone: 831-460-7551
Contact_Facsimile_Telephone: 831-427-4748
Contact_Electronic_Mail_Address: aallwardt@usgs.gov
Process_Step:
Process_Description:
The data release was retroactively assigned a DOI number, and that information was added to the metadata. Additionally, the location of the data release changed, and the metadata links updated accordingly. Other small edits, such as the program name, were also modified.
Process_Date: 202006
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
Added keywords section with USGS persistent identifier as theme keyword (20200908). Fixed one of the USGS Thesaurus terms.
Process_Date: 20211116
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov