Topobathy grid representing the backshore to the nearshore at Head of the Meadow Beach, Truro from data taken during field activity 2020-015-FA on March 6 and 10, 2020

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?
   U.S. Geological Survey, 2021, Topobathy grid representing the backshore to the nearshore at Head of the Meadow Beach, Truro from data taken during field activity 2020-015-FA on March 6 and 10, 2020: data release DOI:10.5066/P9KSG1RQ, 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/P9KSG1RQ
   • https://cmgds.marine.usgs.gov/data/field-activity-data/2020-015-FA/

   This is part of the following larger work.
   Sherwood, C., Traykovski, P., Over, J., Borden, J., Brosnahan, S., Marsjanik, E., and Martini, M., 2021, Topographic and bathymetric data, sediment samples, and imagery collected at Head of the Meadow Beach, Truro in March 2020, U.S Geological Survey Field Activity 2020-015-FA: data release DOI:10.5066/P9KSG1RQ, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P9KSG1RQ

   Other_Citation_Details:

   Over, J.R., Sherwood, C.R., Traykovski, P., Brosnahan, S.M., Martini, M.A., Marsjanik, E., Borden, J., 2021, Topographic and bathymetric data, sediment samples, and beach imagery collected at Head of the Meadow, Truro in March 2020, U.S Geological Survey Field Activity 2020-015-FA: U.S Geological Survey data release, https://doi.org/10.5066/P9KSG1RQ.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -70.08045839
   East_Bounding_Coordinate: -70.07186358
   North_Bounding_Coordinate: 42.05825375
   South_Bounding_Coordinate: 42.05006994
   

3. What does it look like?

   2020015FA_Truro_topobathy_browse.JPG (JPG)

   Depth-colored image of topobathy data collected onshore and offshore of Head of the Meadow Beach, Truro MA

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

   Beginning_Date: 06-Mar-2020

   Ending_Date: 10-Mar-2020

   Currentness_Reference:

   ground condition. Two days of surveying. Bathymetry collected on March 10 and topography collected on March 6.

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. It contains the following raster data types:
      • Dimensions 901 x 701, type Pixel
   2. What coordinate system is used to represent geographic features?
      

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:

      UTM_Zone_Number: 19
      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 North American Datum of 1983 (National Spatial Reference System 2011).
      The ellipsoid used is GRS_80.
      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?

   Entity_and_Attribute_Overview:

   There are no text attributes associated with a binary GeoTIFF image. GeoTIFF pixels represent elevation in meters in reference to NAVD88. No-data values is -32767.

   Entity_and_Attribute_Detail_Citation: USGS Field Activity 2020-015-FA
   

Who produced the data set?

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

   U.S. Geological Survey

   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: 17-Sep-2020 (process 1 of 1)

   The 25 cm Digital Surface Model (DSM) 2020015FA_Truro_DSM_25cm.tif and the 1 m bathymetry grid 2020015FA_Truro_bathymetry_1m.tif (available from the larger work citation) were merged and interpolated over a 1 m grid in MatLab v. 2020b with the following steps.
   1. The data (x,y,z) from the DSM and Bathy grids are combined with the interpolation method regularizedata3d (bicubic interpolation) with a smoothness coefficient of 0.001 (used for data with low noise where the input points nearly coincide with the output surface) by Jamal (2020).
   2. Combined grid is then masked using 'roipoly' which returns the mask as a binary image, setting pixels inside the region of interest polygon to 1 and pixels outside the ROI to 0. The boundary is determined by specifiying the polygon verticies as the regularizedata3D outputs (x,y,z) from the previous step and prevents extrapolation beyong the tracklines of the Bathy and DSM extent.
   3. The final merged GeoTIFF is created using the GRIDobj tool in the TopoToolbox (Schwanghart and Scherler, 2014) which uses the interpolated grid from Step 1 and the mask from step 2 to create the final output. The GeoTIFF is output in NAD83(2011)/UTM Zone 19N in the vertical datum NAVD88 in meters.
   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 Traykovski

   Woods Hole Oceanographic Institue

   Associate Scientist

   226 Woods Hole Rd, MS #12

   Woods Hole, MA
   

   508-289-2638 (voice)

   ptraykovski@whoi.edu

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?
   The GNSS used on the ASV and to collect the imagery used to model the topography has theoretical vertical and horizontal accuracies of 5 meters. See the bathymetry and imagery datasets and metadata in the larger work citation for more details.
2. How accurate are the geographic locations?
   Navigation information was acquired from a GNSS receiver (EMLID Reach M2) in PPK mode with a Multi-band GNSS antenna that has an estimated horizontal accuracy of 5 meters.
3. How accurate are the heights or depths?
   The location information was acquired from a GNSS receiver (EMLID Reach M2) in PPK mode with a Multi-band GNSS antenna and hotshoe adapter with an estimated vertical accuracy of 5 m.
4. Where are the gaps in the data? What is missing?
   This product represent the full extent of the topography and bathymetry available in the larger work citation. 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?
   This file represents the merged 1 meter single beam echo-sounder bathymetry data and digital surface model created from imagery collected by Peter Traykovski or WHOI. These data were combined with post-processed kinematic (PPK) orthometric heights collected using a GNSS receiver (EMLID Reach M2) corrected to a base station (JAVA Triumph) onshore in GEOID 12B NAVD88.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   Jin-Si Over

   U.S. Geological Survey

   geographer

   U.S. Geological Survey

   Woods Hole, MA
   

   508-548-8700 x2269 (voice)

   jover@usgs.gov
2. What's the catalog number I need to order this data set? File 2020015FA_Truro_topobathy_1m.tif containing a 64-bit floating point GeoTIFF grid.
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:	File containing 64-bit floating point GeoTIFF representing a topobathy model of Head of the Meadow Beach, MA in March 2020. in format GeoTIFF (version 1.0.0) 64-bit floating point GeoTIFF format Size: 1.7
     Network links:	https://cmgds.marine.usgs.gov/data/field-activity-data/2020-015-FA/ https://doi.org/10.5066/P9KSG1RQ

   • 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 a 64-bit floating point GeoTIFF image. To utilize these data, the user must have an image viewer, image processing, or GIS software package capable of importing a GeoTIFF image. 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/. The zip file also contains associated metadata.

Who wrote the metadata?

Dates:

Last modified: 18-Mar-2024

Metadata author:

Jin-Si Over

U.S. Geological Survey

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. (updated on 20240318)

Metadata standard:

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