North Carolina Dune and Beach Time Series Features

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   Seymour, Alexander C., and Doran, Kara S., 20260310, North Carolina Dune and Beach Time Series Features:.

   This is part of the following larger work.
   Seymour, Alexander C., and Doran, Kara S., 20260310, Coastal Dune Condition Codes and Time Series Features, North Carolina: U.S. Geological Survey data release doi:10.5066/P9WYA19U, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL.

   Online Links:

   • https://doi.org/10.5066/P9WYA19U

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -78.541634
   East_Bounding_Coordinate: -75.460637
   North_Bounding_Coordinate: 36.546124
   South_Bounding_Coordinate: 33.844975
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 15-Sep-1997

   Ending_Date: 02-Oct-2018

   Currentness_Reference:

   ground condition

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: vector digital data
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Point data set. It contains the following vector data types (SDTS terminology):
      • Point (10172)
   2. What coordinate system is used to represent geographic features?
      

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:

      UTM_Zone_Number: 18N
      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -75.0
      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 0.001
      Ordinates (y-coordinates) are specified to the nearest 0.001
      Planar coordinates are specified in meters
      The horizontal datum used is WGS 1984.
      The ellipsoid used is WGS 1984.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257223563.
      

      Vertical_Coordinate_System_Definition:

      Altitude_System_Definition:

      Altitude_Datum_Name: North American Vertical Datum 1988
      Altitude_Resolution: 0.01
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method: Attribute values
      

7. How does the data set describe geographic features?

   NC_Time_Series_Features_GDB, NC_Time_Series_Features_ASCII.csv

   File geodatabase feature class (.gdb) and comma-separated values file (.csv) of the time series features for North Carolina. (Source: USGS)

   OBJECTID

   Internal feature number. (Source: Esri) Sequential unique whole numbers that are automatically generated.

   Shape

   Feature geometry. This attribute is only present in the feature class dataset. (Source: Esri) Vector type (Point M).

   AlongshoreID

   Unique ID for the alongshore bin. (Source: USGS)

   Range of values
   Minimum:	1
   Maximum:	1033

   MeanDuneElevation

   Average dune crest elevation within each alongshore bin, in meters NAVD88. Null values indicate an individual survey where there were too few dune crest elevation samples found within the 500 m bin to estimate a mean. (Source: USGS)

   Range of values
   Minimum:	0.594267
   Maximum:	10.441828

   DuneElevationSTD

   Dune crest elevation standard deviation within each alongshore bin, in meters. Null values indicate an individual survey where there were too few dune crest elevation samples within a 500 m bin to estimate a standard deviation. (Source: USGS)

   Range of values
   Minimum:	0
   Maximum:	3.500049

   MeanDunePosition

   The mean cross-shore position of the dune crest within each bin relative to the earliest dune crest position mean in the time series, in meters. Negative numbers indicate positions landward of the earliest dune crest. Null values indicate an individual survey where there were too few dune cross shore position samples within a 500 m bin to estimate a mean. (Source: USGS)

   Range of values
   Minimum:	-674.594666
   Maximum:	434.85025

   DunePositionSTD

   Dune crest cross-shore position standard deviation within each alongshore bin, in meters. Null values indicate an individual survey where there were too few dune cross shore position samples within a 500 m bin to estimate a standard deviation. (Source: USGS)

   Range of values
   Minimum:	0
   Maximum:	367.658533

   MeanShorelinePosition

   Mean high water shoreline position within each alongshore bin relative to the earliest shoreline position mean in the time series, in meters. Negative numbers indicate positions landward of the earliest shoreline. Null values indicate an individual survey where there were too few shoreline position samples within a 500 m bin to estimate a mean. (Source: USGS)

   Range of values
   Minimum:	-708.433594
   Maximum:	671.80412231

   MeanBeachWidth

   Average beach width within each alongshore bin, in meters. Null values indicate an individual survey where there were too few beach width samples within a 500 m bin to estimate a mean. (Source: USGS)

   Range of values
   Minimum:	6.960783
   Maximum:	752.538513

   MeanBeachSlope

   Average beach slope within each alongshore bin, in angular degrees. Null values indicate an individual survey where there were too few beach slope samples within a 500 m bin to estimate a mean. (Source: USGS)

   Range of values
   Minimum:	0.155839
   Maximum:	14.707931

   DuneCrestSampleSize

   The number of transects in an alongshore bin with valid dune elevation measurements. (Source: USGS)

   Range of values
   Minimum:	0
   Maximum:	68

   ShorelineSampleSize

   The number of transects in an alongshore bin with valid shoreline position measurements. (Source: USGS)

   Range of values
   Minimum:	0
   Maximum:	70

   SurveyYear

   The year of the survey from which dune and shoreline features were derived. (Source: USGS)

   Range of values
   Minimum:	1997
   Maximum:	2018

   SurveyDate

   String recording the date (MM/DD/YYYY) of the survey from which dune and shoreline features were derived. (Source: USGS)

   Range of values
   Minimum:	09/15/1997
   Maximum:	10/2/2018 Overview_Description:

   XCoord

   Easting (x) coordinate (WGS 84 UTM 18N). (Source: USGS)

   Range of values
   Minimum:	172289.1866
   Maximum:	458262.4674

   YCoord

   Northing (y) coordinate (WGS 84 UTM 18N). (Source: USGS)

   Range of values
   Minimum:	3748925.4136
   Maximum:	4044873.0271

   Entity_and_Attribute_Overview:

   NC_Dune_Condition_Codes_Time_Series_Map_Pack.mpkx: ArcGIS Pro Map Package containing the dune condition codes (NC_Dune_Condition_Codes) and time series features (NC_Time_Series_Features) feature classes, stored inside a file geodatabase (NC_Dune_Condition_Codes_Time_Series.gdb). The Map Package also contains the Hybrid Reference Layer and World Imagery basemaps published by Esri in the Living Atlas. These basemaps are accessible via ArcGIS Online: Hybrid Reference Layer (https://www.arcgis.com/home/item.html?id=30d6b8271e1849cd9c3042060001f425) and World Imagery (https://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer). Scatterplots in the map pack are designed to only display plots from singular condition code points selected by the user. The user must bandbox select a desired condition code point with the Select interactive tool for a scatterplot to display data.

   Entity_and_Attribute_Detail_Citation:

   The entity and attribute information were generated by the individual and/or agency identified originator of the dataset. Please review the metadata records associated with this data release for additional details and information.

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Alexander C. Seymour
   • Kara S. Doran
2. Who also contributed to the data set?
3. To whom should users address questions about the data?
   U.S. Geological Survey

   Attn: Kara S. Doran

   600 4th Street South

   Saint Petersburg, FL
   

   United States

   727-502-8117 (voice)

   727-502-8001 (FAX)

   kdoran@usgs.gov

Why was the data set created?

How was the data set created?

1. From what previous works were the data drawn?
2. How were the data generated, processed, and modified?

   Date: 13-Oct-2022 (process 1 of 3)

   Methods for deriving this data are described in Seymour and others (2026). Additionally, after time series features were generated, an analyst manually removed select points that occurred in inlets where the elevation of shoals was contributing datapoints to the time series. This sometimes occurred after the erosive loss of the subaerial beach and resulted in inaccurate dune elevation and migration change trends. Additional points were removed that were calculated from transects that diverged from shore-normal orientations. Specifically, this could occur most often directly on cape headlands or on spits adjoined to cape headlands. Person who carried out this activity:
   

   Alexander C. Seymour

   U.S. Geological Survey

   Physical Scientist

   600 4th Street South

   Saint Petersburg, FL
   

   United States

   727-502-8122 (voice)

   727-502-8001 (FAX)

   aseymour@usgs.gov

   Data sources produced in this process:

   • NC_Time_Series_Features_GDB

   Date: 13-Oct-2022 (process 2 of 3)

   The data included in this release is a point feature class of time series features stored in a file geodatabase (.gdb), along with a comma-delimited ASCII table (.csv) for users that do not have the ability to open and view Geographic Information Systems (GIS) file formats. The time series ASCII table was generated by inputting the geodatabase feature classes into the ‘Feature Class to ASCII’ ArcGIS Pro geoprocessing tool. Person who carried out this activity:
   

   Alexander C. Seymour

   U.S. Geological Survey

   Physical Scientist

   600 4th Street South

   Saint Petersburg, FL
   

   United States

   727-502-8122 (voice)

   727-502-8001 (FAX)

   aseymour@usgs.gov

   Data sources used in this process:

   • NC_Time_Series_Features_GDB

   Data sources produced in this process:

   • NC_Time_Series_Features_ASCII

   Date: 13-Oct-2022 (process 3 of 3)

   To include additional visualizations of the feature class data, an ArcGIS Pro Map Package (.mpkx) was generated, which contains specific symbolization of the feature classes and charts that aid the user in interpreting and visualizing some of the most important attributes in the data. The geodatabase feature classes, both the time series feature described in this metadata record (NC_Time_Series_Features_GDB), and the dune condition code (NC_Dune_Condition_Codes_GDB, described in NC_Dune_Condition_Code_Metadata) were added to a new ArcGIS Pro map. interactively symbolizing the features appropriately, and creating scatterplot and bar plot graph schema for the feature classes. The Hybrid Reference Layer and World Imagery basemaps were also added to the map layout. For more information about these basemaps, refer to: Hybrid Reference Layer (https://www.arcgis.com/home/item.html?id=30d6b8271e1849cd9c3042060001f425) and World Imagery (https://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer). The map and its associated schema were then exported to a Map Package by clicking the ‘New Map Package’ command in the ‘Share’ tab in ArcGIS Pro. Person who carried out this activity:
   

   Alexander C. Seymour

   U.S. Geological Survey

   Physical Scientist

   600 4th Street South

   Saint Petersburg, FL
   

   United States

   727-502-8122 (voice)

   727-502-8001 (FAX)

   aseymour@usgs.gov

   Data sources used in this process:

   • NC_Dune_Condition_Codes_Time_Series.gdb
   • NC_Time_Series_Features_GDB
   • NC_Dune_Condition_Codes_GDB

   Data sources produced in this process:

   • NC_Dune_Condition_Codes_Time_Series_Map_Pack.mpkx
   • NC_Dune_Condition_Codes_Time_Series.zip

3. What similar or related data should the user be aware of?
   Seymour, Alexander C., Ciarletta, Daniel J., Doran, Kara S., Parker, Kai, and Palmsten, Margaret L., 20260305, Decadal-scale characteristics of natural and anthropogenic dune morphology along North Carolina barrier islands (SE Atlantic coast): Journal of Coastal Research Unknown.

   Online Links:

   • https://doi.org/10.2112/JCOASTRES-D-25-00053.1

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

1. How well have the observations been checked?
   
2. How accurate are the geographic locations?
   No formal accuracy assessment is included. Horizontal positions were projected to the World Geodetic System of 1984 (WGS 84) Universal Transverse Mercator Zone 18 North (UTM 18N) coordinate system.
3. How accurate are the heights or depths?
   No formal accuracy assessment is included. Vertical positions were referenced to the North American Vertical Datum of 1988 (NAVD88).
4. Where are the gaps in the data? What is missing?
   This dataset is considered complete for the information presented, as described in the abstract section. Users are advised to read the rest of the metadata record carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   No formal accuracy assessment was conducted.

How can someone get a copy of the data set?

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? NC_Dune_Time_Series_GDB.gdb, NC_Dune_Time_Series_ASCII.csv, NC_Dune_Condition_Codes_Time_Series_Map_Pack.mpkx
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?
   • Availability in digital form:

     Data format:	comma-delimited text, file geodatabase (Esri), ArcGIS Pro Map Package (version ArcGIS Pro 3.0.3)
     Network links:	https://coastal.er.usgs.gov/data-release/doi-P9WYA19U/data/NC_Dune_Condition_Codes_Time Series.zip

   • Cost to order the data: None

5. What hardware or software do I need in order to use the data set?
   The geodatabase feature class and ArcGIS Map Package were created for the use within Esri ArcGIS Pro software (3.0.3 or newer). The ASCII table data were created for the use within Microsoft Excel, or similar text viewers, such as Notepad.

Who wrote the metadata?

Dates:

Last modified: 10-Mar-2026

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)