Topobathy Products in Pea Island National Wildlife Refuge, North Carolina in November 2020 and April, September, and October 2021

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?
   Traykovski, Peter A., and Over, Jin-Si R., 20220607, Topobathy Products in Pea Island National Wildlife Refuge, North Carolina in November 2020 and April, September, and October 2021: data release DOI:10.5066/P9DPZZG2, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

   Online Links:

   • https://doi.org/10.5066/P9DPZZG2
   • https://www.sciencebase.gov/catalog/item/623dcb84d34e915b67d65441

   This is part of the following larger work.
   Over, Jin-Si R., Sherwood, Christopher R., Traykovski, Peter A., Brosnahan, Sandra M., Olson, Alex J., and Randall, Noa R., 2022, DUNEX topographic, bathymetric, and supporting GPS data collected in Pea Island National Wildlife Refuge, North Carolina 2020-2021: data release DOI:10.5066/P9DPZZG2, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P9DPZZG2
   • https://www.sciencebase.gov/catalog/item/623dca6cd34e915b67d65110

   Other_Citation_Details:

   Over, J.R., Sherwood, C.R., Traykovski, P.A., Olson, A.J., Randall, N.R., and Brosnahan, S.M., 2022, DUNEX topographic, bathymetric, and supporting GPS data collected in Pea Island National Wildlife Refuge, North Carolina 2020-2021: U.S Geological Survey data release, https://doi.org/10.5066/P9DPZZG2.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -75.52598572
   East_Bounding_Coordinate: -75.45864965
   North_Bounding_Coordinate: 35.76604133
   South_Bounding_Coordinate: 35.67291791
   

3. What does it look like?

   https://www.sciencebase.gov/catalog/file/get/623dcb84d34e915b67d65441?name=PINWR_Topobathy_browse.JPG&allowOpen=true (JPEG)

   Example elevation colored topobathy grid in Pea Island National Wildlife Refuge.

4. Does the data set describe conditions during a particular time period?

   Calendar_Date: 22-Nov-2020

   Currentness_Reference:

   Ground condition; data collected on multiple days but surveys have been combined into topobathy grids: 20201122, 20201125, and 20201127; 20210419 and 20210420; 20210907 and 20210908; 20210926 and 20210928; 20211019 and 20211020.

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

   Geospatial_Data_Presentation_Form: raster digital data
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Raster 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: 18
      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.999600
      Longitude_of_Central_Meridian: -69.000000
      Latitude_of_Projection_Origin: 0.000000
      False_Easting: 500000.000000
      False_Northing: 0.000000
      

      Planar coordinates are encoded using row and column
      Abscissae (x-coordinates) are specified to the nearest 1
      Ordinates (y-coordinates) are specified to the nearest 1
      Planar coordinates are specified in meters
      The horizontal datum used is NAD83_National_Spatial_Reference_System_2011.
      The ellipsoid used is GRS_1980.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222101.
      

      Vertical_Coordinate_System_Definition:

      Altitude_System_Definition:

      Altitude_Datum_Name: North American Vertical Datum of 1988
      Altitude_Resolution: 0.001
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method:

      Explicit elevation coordinate included with horizontal coordinates

7. How does the data set describe geographic features?

   2020024DD_PINWR_DUNEX_Topobathy_1m_1122-25-27_cog.tif

   A 1-m raster dataset (NAD83[2011]/UTM Zone 18N GeoTIFF) with encoded elevation values from bathymetry collected on November 22 and 27, 2020 and walking survey topography from November 22 and 25, 2020 at the Pea Island National Wildlife Refuge DUNEX site. (Source: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program)

   Value

   Elevation relative to NAVD88 (m) using Geoid 2012B (Source: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center)

   Range of values
   Minimum:	-10.655
   Maximum:	5.915
   Units:	meters

   2020024DD_PINWR_DUNEX_Topobathy_1m_0419-20_cog.tif

   A 1-m raster dataset (NAD83[2011]/UTM Zone 18N GeoTIFF) with encoded elevation values from bathymetry collected on April 19 and 20, 2021 and walking survey topography from April 20, 2021 at the Pea Island National Wildlife Refuge DUNEX site. (Source: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program)

   Value

   Elevation relative to NAVD88 (m) using Geoid 2012B (Source: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center)

   Range of values
   Minimum:	-17.836
   Maximum:	5.078
   Units:	meters

   2020024DD_PINWR_BB_Topobathy_1m_0420_cog.tif

   A 1-m raster dataset (NAD83[2011]/UTM Zone 18N GeoTIFF) with encoded elevation values from bathymetry and walking survey topography collected on April 20, 2021 at the Pea Island National Wildlife Refuge Basnight Bridge site. (Source: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program)

   Value

   Elevation relative to NAVD88 (m) using Geoid 2012B (Source: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center)

   Range of values
   Minimum:	-11.079
   Maximum:	0.684
   Units:	meters

   2021029FA_PINWR_DUNEX_Topobathy_1m_0907-08_cog.tif

   A 1-m raster dataset (NAD83[2011]/UTM Zone 18N GeoTIFF) with encoded elevation values from bathymetry collected on September 7, 2021 and Helikite survey topography from September 8, 2021 at the Pea Island National Wildlife Refuge DUNEX site. (Source: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program)

   Value

   Elevation relative to NAVD88 (m) using Geoid 2012B (Source: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center)

   Range of values
   Minimum:	-8.019
   Maximum:	7.629
   Units:	meters

   2021029FA_PINWR_DUNEX_Topobathy_1m_0911-12_cog.tif

   A 1-m raster dataset (NAD83[2011]/UTM Zone 18N GeoTIFF) with encoded elevation values from bathymetry collected on September 12, 2021 and Helikite survey topography from September 11, 2021 at the Pea Island National Wildlife Refuge DUNEX site. (Source: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program)

   Value

   Elevation relative to NAVD88 (m) using Geoid 2012B (Source: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center)

   Range of values
   Minimum:	-17.319
   Maximum:	8.237
   Units:	meters

   2021029FA_PINWR_DUNEX_Topobathy_1m_0926-28_cog.tif

   A 1-m raster dataset (NAD83[2011]/UTM Zone 18N GeoTIFF) with encoded elevation values from bathymetry collected on September 28, 2021 and Helikite survey topography from September 26, 2021 at the Pea Island National Wildlife Refuge DUNEX site. (Source: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program)

   Value

   Elevation relative to NAVD88 (m) using Geoid 2012B (Source: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center)

   Range of values
   Minimum:	-9.982
   Maximum:	7.644
   Units:	meters

   2021029FA_PINWR_DUNEX_Topobathy_1m_1019-20_cog.tif

   A 1-m raster dataset (NAD83[2011]/UTM Zone 18N GeoTIFF) with encoded elevation values from bathymetry collected on October 19 and 20, 2021 and Helikite survey topography from October 19, 2021 at the Pea Island National Wildlife Refuge DUNEX site. (Source: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program)

   Value

   Elevation relative to NAVD88 (m) using Geoid 2012B (Source: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center)

   Range of values
   Minimum:	-9.994
   Maximum:	7.428
   Units:	meters

   Entity_and_Attribute_Overview:

   There are seven topobathy grids represent elevation in meters relative to the NAVD88 datum. The cloud optimized GeoTIFFs have no-data values of -3.402823E38. The naming convention is as follows: the USGS field name 2020024DD or 2021029FA; location is Pea Island National Wildlife Refuge (PINWR) at either the DUNEX or Basnight Bridge (BB) site; product is Topobathy; resolution is 1-meter; and date is in MMDD-DD to provide context if data were collected on multiple days for the final grid.

   Entity_and_Attribute_Detail_Citation: USGS Field Activity 2021-029-FA and Donated Data 2020-024-DD
   

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Peter A. Traykovski
   • Jin-Si R. Over
2. Who also contributed to the data set?
3. To whom should users address questions about the data?
   Jin-Si R. Over

   U.S. Geological Survey, Northeast Region: Woods Hole Coastal and Marine Science Center

   U.S. Geological Survey

   Woods Hole, MA
   

   508-548-8700 x2269 (voice)

   jover@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: Mar-2022 (process 1 of 2)

   The bathymetry and topography data are provided in the larger citation. Data are merged using the following steps. 1. The data (x,y,z) from the DSM and Bathy grids were combined with the interpolation method regularizedata3d (bicubic interpolation) using a smoothness coefficient of 0.001 (appropriate for data with low noise where the input points nearly coincide with the output surface) by Jamal (2020). 2. The combined grid was then masked using 'roipoly' which returned the mask as a binary image, setting pixels inside the region of interest (ROI) polygon to 1 and pixels outside the ROI to 0. The boundary was determined by specifying the polygon vertices as the regularizedata3D outputs (x,y,z) from the previous step and prevented extrapolation beyond the tracklines of the Bathy and DSM extent. 3. The final merged GeoTIFF was created using the GRIDobj tool in the TopoToolbox (Schwanghart and Scherler, 2014) which used the interpolated grid and the mask from step 2 to create the final output. 4. Export gridded 1 m data in NAD83(2011)/UTM Zone 18N in NAVD88 meters, using Geoid 12B, as a GeoTIFF. Note that using NAVD88 as a height means that the depths are not true-depths but the elevation of the seafloor above or below the geoid. Schwanghart, W., Scherler, D. (2014): TopoToolbox 2 ‚ MATLAB-based software for topographic analysis and modeling in Earth surface sciences. Earth Surface Dynamics, 2, 1-7. [DOI: 10.5194/esurf-2-1-2014] Jamal (2020). RegularizeData3D (https://www.mathworks.com/matlabcentral/fileexchange/46223-regularizedata3d), MATLAB Central File Exchange. Retrieved September 23, 2020. Person who carried out this activity:
   

   Peter A. Traykovski

   Woods Hole Oceanographic Institution

   Associate Scientist

   226 Woods Hole Rd, MS #12

   Woods Hole, MA
   

   508-289-2638 (voice)

   ptraykovski@whoi.edu

   Date: 12-May-2022 (process 2 of 2)

   The grids were converted into cloud optimized GeoTiffs (cog) and assigned a nodata value of -3.402823E38 using gdal_translate with the following command: for %i in (.\*.tif) do gdal_translate %i .\cog\%~ni_cog.tif -co COMPRESS=LZW -co COPY_SRC_OVERVIEWS=YES -co BIGTIFF=YES -co TILED=YES -nodata value= -3.402823E38 Where i was the name of each geoTIFF section and there is an empty folder named cog in the directory. Person who carried out this activity:
   

   Jin-Si R. Over

   U.S. Geological Survey, Northeast Region: Woods Hole Coastal and Marine Science Center

   Geographer

   384 Woods Hole Rd.

   Woods Hole, MA
   

   508-548-8700 x2269 (voice)

   jover@usgs.gov

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?
   All elevation values are internally consistent in relation to each other and are comparable to values of published topobathy in the area (e.g. 2022 USGS CoNED Topobathy DEM (1851 - 2020): Coastal Carolinas, available at https://www.fisheries.noaa.gov/inport/item/67013, accessed May 18, 2022).
2. How accurate are the geographic locations?
   Navigation information was acquired from the GNSS receiver in PPK mode with a Multi-band GNSS antenna that has a theoretical horizontal accuracy of 1-5 cm and average reported SD of 1.0 cm. See the larger citation for detailed accuracy reports on the bathymetry and topography.
3. How accurate are the heights or depths?
   The location information was acquired from the GNSS receiver in PPK mode with a Multi-band GNSS antenna and hot shoe adapter with a theoretical horizontal accuracy of 1-5 cm and average reported SD of 1.6 cm. See the larger citation for detailed accuracy reports on the bathymetry and topography.
4. Where are the gaps in the data? What is missing?
   Not all combinations of topography and bathymetry were merged from the raw data. The best coverage and completeness of the topography and bathymetry collected within two days of each other were used to produce the merged products.
5. How consistent are the relationships among the observations, including topology?
   These grids represent merged grids of single beam echo-sounder bathymetry data collected by Peter Traykovski (WHOI) and collected topographic data from the larger citation. Raw data is provided in the larger citation.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey - ScienceBase

   Denver Federal Center, Building 810, Mail Stop 302

   Denver, CO
   

   1-888- 275-8747 (voice)

   sciencebase@usgs.gov
2. What's the catalog number I need to order this data set? Each file represents a merged interpolated topobathy grid of elevation values in Pea Island National Wildlife Refuge.
3. What legal disclaimers am I supposed to read?
   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 U.S. Geological Survey 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.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	Merged grids of single beam bathymetric data collected by Peter Traykovski (WHOI) and topography data collected during field activity 2021-029-FA and from donated data 2020-024-DD. in format GeoTIFF (version 1.0.0) GeoTIFF Size: 21
     Network links:	https://www.sciencebase.gov/catalog/file/get/623dcb84d34e915b67d65441 https://www.sciencebase.gov/catalog/item/623dcb84d34e915b67d65441 https://doi.org/10.5066/P9DPZZG2

   • Cost to order the data: None.

5. What hardware or software do I need in order to use the data set?
   These data are available as cloud optimized GeoTIFF rasters. To utilize these data, the user must have an image viewer, image processing, GIS software package capable of importing a GeoTIFF, and a way to unzip the raw data. Free spatial data viewers or proprietary software such as ArcGIS Earth or Google Earth Pro are capable of displaying the data. See: http://www.esri.com/software/arcgis-earth, or https://www.google.com/earth/desktop/.

Who wrote the metadata?

Dates:

Last modified: 07-Jun-2022

Metadata author:

Jin-Si R. Over

U.S. Geological Survey, Northeast Region: Woods Hole Coastal and Marine Science Center

Geographer

U.S. Geological Survey

Woods Hole, MA

508-548-8700 x2269 (voice)

whsc_data_contact@usgs.gov

Contact_Instructions:

The metadata contact email address is a generic address in the event the person is no longer with USGS.

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)