Waves, fetch, and associated shoreline change for the Point Aux Chenes and Grand Bay Estuaries in Mississippi and Alabama

Metadata also available as - [Outline] - [Parseable text] - [XML]

Frequently anticipated questions:

What does this data set describe?

Title:
Waves, fetch, and associated shoreline change for the Point Aux Chenes and Grand Bay Estuaries in Mississippi and Alabama
Abstract:
This dataset represents a compilation of waves, fetch, and associated shoreline change rates from the Point Aux Chenes and Grand Bay estuaries (Mississippi and Alabama) for historical, modern, and long-term time periods.
  1. How might this data set be cited?
    Smith, Kathryn E.L., Terrano, Joseph F., and Jenkins, Robert L. III, 20241113, Waves, fetch, and associated shoreline change for the Point Aux Chenes and Grand Bay Estuaries in Mississippi and Alabama:.

    This is part of the following larger work.

    Terrano, Joseph F., Smith, Kathryn E.L., Pitchford, Jonathan, and Jenkins, Robert L. III, 20241113, Estuarine Shoreline, Upland Boundary, and Marsh Habitat Change Analyses for the Point Aux Chenes and Grand Bay Estuary Systems, Mississippi and Alabama: U.S. Geological Survey data release doi:10.5066/P1HZES2R, U.S. Geological Survey, St. Petersburg, FL.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -88.476727
    East_Bounding_Coordinate: -88.312934
    North_Bounding_Coordinate: 30.402042
    South_Bounding_Coordinate: 30.315210
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date:
    Ending_Date: 31-Jan-2023
    Currentness_Reference:
    ground condition
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: tabular digital data
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Vector data set.
    2. What coordinate system is used to represent geographic features?
      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:
      UTM_Zone_Number: 16
      Transverse_Mercator:
      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -87.0
      Latitude_of_Projection_Origin: 0.0
      False_Easting: 500000.0
      False_Northing: 0.0
      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.6096
      Ordinates (y-coordinates) are specified to the nearest 0.6096
      Planar coordinates are specified in Meter
      The horizontal datum used is D_North_American_1983.
      The ellipsoid used is GRS_1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257222101.
  7. How does the data set describe geographic features?
    GB_SLC_waves.csv
    Table comparing attribute information associated with 1) long term, historical, and modern shoreline change, 2) wave energy, and 3) wave power for Grand Bay MS/AL. (Source: USGS)
    Transect
    Identification number assigned to each transect. If a number is missing, then the transect was not used in the analysis and was removed from the table. (Source: AMBUR)
    Range of values
    Minimum:1
    Maximum:839
    lon
    Longitude in the North American Datum of 1983 Universal Transverse Mercator Zone 16 North (NAD83 UTM 16N). (Source: USGS)
    Range of values
    Minimum:358017.706
    Maximum:373850.4767
    Units:Meters
    lat
    Latitude in the North American Datum of 1983 Universal Transverse Mercator Zone 16 North (NAD83 UTM 16N). (Source: USGS)
    Range of values
    Minimum:3354637.157
    Maximum:3364116.843
    Units:Meters
    segment
    Transects were grouped into two-kilometers segments for analysis. (Source: USGS)
    Range of values
    Minimum:1
    Maximum:20
    LRR_lt
    Long-term linear regression rate (LRR) calculated using all available shorelines between 1848 and 2023. (Source: USGS)
    Range of values
    Minimum:-6.551854643
    Maximum:0.393206096
    Units:Meters per year (m/yr)
    LRR_his
    Historical linear regression rate (LRR) calculated using all available shorelines between 1848 and 1957. (Source: USGS)
    Range of values
    Minimum:-6.843260831
    Maximum:1.654319395
    Units:Meters per year (m/yr)
    LRR_mod
    Modern linear regression rate (LRR) calculated using all available shorelines between 1957 and 2023. (Source: USGS)
    Range of values
    Minimum:-9.996045782
    Maximum:1.908480843
    Units:Meters per year (m/yr)
    WE
    Wave energy. (Source: USGS)
    Range of values
    Minimum:0
    Maximum:73.88345996
    Units:Joules per square meter (J/m2)
    Pwr
    Wave power. (Source: USGS)
    Range of values
    Minimum:0
    Maximum:153.4516456
    Units:Watts per meter (W/m)
    LRR_lt_n3
    Linear regression rate (LRR) calculated using the 1848, 1957, and 2022 shorelines. The ".n3" in the field name denotes only 3 shorelines were used. (Source: USGS)
    Range of values
    Minimum:-6.843260831
    Maximum:1.239509864
    Units:Meters per year (m/yr)
    EPR_his
    End point rate (EPR) calculated using the 1848 and 2022 shorelines. EPR is the distance between the oldest and youngest shoreline divided by time. (Source: USGS)
    Range of values
    Minimum:-6.843260831
    Maximum:1.756510647
    Units:Meters per year (m/yr)
    EPR_mod
    End point rate (EPR) calculated using the 1957 and 2022 shorelines. EPR is the distance between the oldest and youngest shoreline divided by time. Blank cells indicate no data. (Source: USGS)
    Range of values
    Minimum:-6.914018206
    Maximum:1.844308912
    Units:Meters per year (m/yr)
    GB_fetch_his.csv, GB_fetch_mod.csv, SRI_fetch_his.csv, and SRI_fetch_mod.csv
    Tables containing information associated fetch for 1) historical full study area coverage (GB_fetch_his.csv), 2) modern full study area coverage (GB_fetch_mod.csv), 3) historical relict south Rigolets Island coverage (SRI_fetch_his.csv), and 4) modern relict south Rigolets Island coverage (SRI_fetch_mod.csv) (Source: USGS)
    Transect
    Identification number assigned to each transect. If a number is missing, then the transect was not used in the analysis and does not have data. Transects 1-839 are in the GB fetch files and transects 840-954 are in the SRI fetch files. (Source: AMBUR)
    Range of values
    Minimum:1
    Maximum:954
    fetch
    Fetch calculated using historic and modern mainland and barrier island shorelines. Maximum length a fetch transect could be was 1,600 kilometers. (Source: USGS)
    Range of values
    Minimum:0.001193295
    Maximum:1421.470682
    Units:Kilometers
    direction
    Direction the fetch transect extends from the shoreline point with North at 0° proceeding clockwise. Each shoreline point started with 16 fetch transects. The 16 transects were in consistent directions across all the points. Transects that point back towards the Grand Bay marsh platform were removed from the final dataset. (Source: USGS)
    Range of values
    Minimum:0
    Maximum:337.5
    Units:Degrees
    quadrant
    Direction of the transect based on which quadrant (North, South, East, West) it extends into. (Source: USGS) Direction of the transect based on which quadrant (North, South, East, West) it extends into. Each of the quadrants has up to 4 transects.
    x_start
    X start coordinate in the North American Datum of 1983 Universal Transverse Mercator Zone 16N (NAD83 UTM 16N). (Source: USGS)
    Range of values
    Minimum:357966.8548
    Maximum:374028.4746
    Units:Meters
    y_start
    Y start coordinate in the North American Datum of 1983 Universal Transverse Mercator Zone 16N (NAD83 UTM 16N). (Source: USGS)
    Range of values
    Minimum:3354845.754
    Maximum:3364507.633
    Units:Meters
    x_end
    X end coordinate in the North American Datum of 1983 Universal Transverse Mercator Zone 16N (NAD83 UTM 16N). (Source: USGS)
    Range of values
    Minimum:-182186.2448
    Maximum:1145818.191
    Units:Meters
    y_end
    Y end coordinate in the North American Datum of 1983 Universal Transverse Mercator Zone 16N (NAD83 UTM 16N). (Source: USGS)
    Range of values
    Minimum:2049380.438
    Maximum:3364610.617
    Units:Meters

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Kathryn E.L. Smith
    • Joseph F. Terrano
    • Robert L. Jenkins III
  2. Who also contributed to the data set?
    Acknowledgment of the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, as a data source would be appreciated in products developed from these data, and such acknowledgment as is standard for citation and legal practices. Sharing of new data layers developed directly from these data would also be appreciated by the U.S. Geological Survey staff. Comparisons with other historical datasets for the same area from other time periods may be inaccurate due to inconsistencies resulting from changes in photointerpretation, mapping conventions, and digital processes over time. These data are not legal documents and are not to be used as such.
  3. To whom should users address questions about the data?
    U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center
    Attn: Joseph F. Terrano
    Physical Scientist
    600 4th Street South
    St. Petersburg, FL

    727-502-8047 (voice)
    727-502-8182 (FAX)
    jterrano@usgs.gov

Why was the data set created?

The purpose of these data is to examine the historical, modern, and long-term trends related to waves, fetch, and associated shoreline change rates from the Point Aux Chenes and Grand Bay estuaries in Mississippi and Alabama.

How was the data set created?

  1. From what previous works were the data drawn?
    Buster and Morton (2011) (source 1 of 4)
    Buster, N. A., and Morton, R.A., 20110404, Historical bathymetry and bathymetric change in the Mississippi-Alabama coastal region, 1847–2009: U.S. Geological Survey, Reston, VA.

    Online Links:

    Type_of_Source_Media: digital data
    Source_Contribution:
    Shorelines and bathymetry from 1848 for sections of the Mississippi and Alabama mainland and barrier islands.
    Guy (2015) (source 2 of 4)
    Guy, K.K., 2015, Shorelines extracted from Landsat imagery: Petit Bois Island, Mississippi: U.S. Geological Survey, St. Petersburg, Florida.

    Online Links:

    Type_of_Source_Media: digital data
    Source_Contribution: Modern shorelines from 2015 for Petit Bois Island, Mississippi.
    Henderson and others (2017) (source 3 of 4)
    Henderson, R.E., Nelson, P.R., Long, J.W., and Smith, C.G., 20170616, Vector shorelines and associated shoreline change rates derived from lidar and aerial imagery for Dauphin Island, Alabama: 1940–2015: U.S. Geological Survey, St. Petersburg, Florida.

    Online Links:

    Type_of_Source_Media: digital data
    Source_Contribution:
    Lidar and aerial imagery derived shorelines from 2015 for Dauphin Island, Alabama.
    OpenStreetMap contributors (2022) (source 4 of 4)
    contributors, OpenStreetMap, 2022, Data Derived from OpenStreetMap for Download: OpenStreetMap Foundation, Online.

    Online Links:

    Type_of_Source_Media: digital data
    Source_Contribution:
    Shorelines from 2022 of mainland and barrier islands derived using the OpenStreetMapsCoastlines (OSMCoastlines) tool.
  2. How were the data generated, processed, and modified?
    Date: 2024 (process 1 of 3)
    Fetch length was calculated for sixteen wind directions at each shoreline location where shoreline change was estimated, using both the modern (2022) and historic (1848) shoreline data and temporally coincident offshore barrier island configuration. To generate historic fetch, the 1848 shoreline and historic mid-18th century offshore northern Gulf of Mexico (GOM) barrier island shoreline data (data for barrier islands were published in Buster and Morton, 2011) were combined to create the best available data for this timeframe. Since some fetch distances extend across the GOM (to mainland Florida, Mexico, etc.) and historic geospatial data for the entire GOM are not available, the historic data was merged with a modern shoreline data set for the remainder distant GOM shorelines (OpenStreetMap contributors, 2022), assuming the relative changes at this scale was minimal. For modern fetch, the most recent barrier island configuration from 2015 (Guy 2015; Henderson and others 2017) was combined with the modern Grand Bay and GOM shorelines available. The 2015 barrier island shoreline was checked against recent 2022 imagery and determined that, aside from some minor changes in spit lengths, it had not significantly changed position. At the same locations where shoreline change was determined, sixteen vectors (one vector every 22.5° with North at 0°) were extended from the Grand Bay shoreline to the closest land mass (barrier island or mainland) with a maximum distance of 1,600 kilometers (km) using the R package fetchR (version 2.1-0). Vectors pointing toward land were removed. The results are presented in four files. Historic and modern fetch for the entire Grand Bay region are presented as comma-separated values files (GB_fetch_his.csv and GB_fetch_mod.csv). A second analysis was completed that calculated historic and modern fetch for transects only covering the relict South Rigolets Island (SRI) and are also presented .csv files (SRI_fetch_his.csv and SRI_fetch_mod.csv). Coordinates for these four files are displayed in the North American Datum of 1983 (NAD83). Person who carried out this activity:
    Kathryn E.L. Smith
    Research Ecologist
    600 4th Street South
    St. Petersburg, FL
    USA

    727-502-8073 (voice)
    kelsmith@usgs.gov
    Data sources used in this process:
    • Buster and Morton (2011)
    • OpenStreetMap contributors (2022)
    • Guy (2015)
    • Henderson and others (2017)
    Data sources produced in this process:
    • GB_fetch_his.csv
    • GB_fetch_mod.csv
    • SRI_fetch_his.csv
    • SRI_fetch_mod.csv
    Date: 2024 (process 2 of 3)
    A characterization of wave power was generated using modeled, climatologically driven, wind waves (Masselink and others, 2014). Wave power was calculated from modeled wind waves for fair weather conditions using a probabilistic Delft3D model arrangement previously described and published (Jenkins and others, 2023a; Jenkins and others, 2023b). The model was forced by wind and wave climatology (Benedet and others, 2016) informed by local wind history. Characteristic wave power within Grand Bay was calculated under current conditions using the weighted sum of time-averaged waves produced by a one-year probabilistic model run (Jenkins and others, 2023a) and weighting based on the frequency of occurrence of individual climatologic conditions. Person who carried out this activity:
    Kathryn E.L. Smith
    Research Ecologist
    600 4th Street South
    St. Petersburg, FL
    USA

    727-502-8073 (voice)
    kelsmith@usgs.gov
    Data sources produced in this process:
    • GB_shoreline change_waves.csv
    Date: 2024 (process 3 of 3)
    Shorelines (and original shoreline source information), transects, and shoreline change methods are published as part of this data release as Shoreline_change_analysis.zip. The GB_SLC_waves.csv file pertaining to this metadata contains rates calculated using data contained within Shoreline_change_analysis.zip. Compiled shorelines were processed using the Analyzing Moving Boundaries Using R (AMBUR) statistical package for R (version 4.0.4) to add required missing attributes and calculate shoreline change rates. More information on the AMBUR program can be obtained from Jackson (2010). The "LRR.lt" field used all available 1848-2023 shorelines. The "LRR.his" and "LRR.mod" fields used subsets of these shorelines from 1848-1957 and 1957-2023, respectively. The "LRR.lt.n3" field only used shorelines from 1848, 1957, and 2022. The "EPR.his" field only used 1848 and 1957 and "EPR.mod" field only used 1957 and 2022. The following analysis parameters were used: first intersection (if transect intersects the same shoreline more than once, then by default it selected the first intersection), confidence level 95 (confidence level for the linear regression statistics), unit label m (the units of measure for the map is for Universal Transverse Mercator and in meters), analysis type is advanced (advanced includes additional statistics for a robust linear regression), and time unit for rates is yr (utilizes years for calculating rates of shoreline change). Linear regression rate (LRR) and end point rate (EPR) were calculated as part of this study. LRR was not calculated for transects that intersected less than 3 shorelines. Coordinates are displayed in the North American Datum of 1983 Universal Transverse Mercator Zone 16 North (NAD83 UTM 16N). Person who carried out this activity:
    Kathryn E.L. Smith
    Research Ecologist
    600 4th Street South
    St. Petersburg, FL
    USA

    727-502-8073 (voice)
    kelsmith@usgs.gov
    Data sources produced in this process:
    • GB_shoreline change_waves.csv
  3. What similar or related data should the user be aware of?
    Jackson, C.W., Jr., 2010, Basic User Guide for the AMBUR package for R: Chester W. Jackson Jr., Online.

    Online Links:

    Masselink, G., Hughes, M., and Knight, J., 20140306, Introduction to coastal processes and geomorphology: Routledge, New York.

    Online Links:

    Benedet, L., Dobrochinski, J.P.F., Walstra, D.J.R., Klein, A.H.F., and Ranasinghe, R., 20160403, A morphological modeling study to compare different methods of wave climate schematization and evaluate strategies to reduce erosion losses from a beach nourishment project: Coastal Engineering Volume 112, Elsevier, Online.

    Online Links:

    Other_Citation_Details: Pages 69-86
    Jenkins, R.L. III, Passeri, D.L., Smith, C.G., Thompson, D.M., and Smith, K.E.L., 20230815, Modeling the effects of interior headland restoration on estuarine sediment transport processes in a marine-dominant estuary: Frontiers in Marine Science - Coastal Ocean Processes Volume 10-2023, Frontiers in Marine Science, Online.

    Online Links:

    Other_Citation_Details: Jenkins and others, 2023a
    Jenkins, R.L. III, Passeri, D.L., Smith, C.G., and Thompson, D.M., 20230810, Modeling the effects of interior headland restoration on estuarine sediment transport processes in a marine-dominant estuary: Delft3D model output:: U.S. Geological Survey data release doi:10.5066/P986ZR6B, U.S. Geological Survey, St. Petersburg, Florida.

    Online Links:

    Other_Citation_Details: Jenkins and others, 2023b

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    Shoreline change rates are influenced by availability and accuracy of shoreline data. Analyses of highly dynamic areas are particularly challenging, including 1) areas near inlets, where there are excessively dynamic depositional/erosional sand bars that may appear/disappear rapidly, and 2) tidal creeks, where the land/water line is hard to distinguish due to sporadic vegetation lines. Fetch was derived using the R package fetchR. Waves were derived from a probabilistic Delft3D model previously published by Jenkins and others (2023a, 2023b).
  2. How accurate are the geographic locations?
    A formal accuracy assessment of the horizontal positional information in the dataset has not been conducted. For additional information on data collection techniques see the source metadata for the shorelines and wave data.
  3. How accurate are the heights or depths?
    Several factors may influence the accuracy and uncertainty of shoreline position for vegetated shorelines, such as water level. Water level at the time of imagery collection is largely unknown for most historical imagery, therefore USGS staff cannot account for shoreline positional errors associated with water level. For additional information on data collection techniques or imagery information, please refer to the source agency or source metadata.
  4. Where are the gaps in the data? What is missing?
    Data described in this metadata are considered complete as of the time of publication.
  5. How consistent are the relationships among the observations, including topology?
    Vector features and attributes were checked for completeness and accuracy.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints None
Use_Constraints The U.S. Geological Survey requests to be acknowledged as originator of the data in future products or derivative research.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
    Attn: USGS SPCMSC Data Management
    600 4th Street South
    Saint Petersburg, FL
    United States

    727-502-8000 (voice)
    gs-g-spcmsc_data_inquiries@usgs.gov
  2. What's the catalog number I need to order this data set? GB_SLC_waves.csv, GB_fetch_his.csv, GB_fetch_mod.csv, SRI_fetch_his.csv, and SRI_fetch_mod.csv
  3. What legal disclaimers am I supposed to read?
    This digital publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 13-Nov-2024
Metadata author:
U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
Attn: USGS SPCMSC Data Management
600 4th Street South
Saint Petersburg, FL
United States

727-502-8000 (voice)
gs-g-spcmsc_data_inquiries@usgs.gov
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/spcmsc/SLC_waves_fetch_metadata.faq.html>
Generated by mp version 2.9.51 on Wed Nov 13 11:36:15 2024