Structure from motion GCPs, digital surface model, and orthomosaic representing Marconi Beach, Wellfleet, MA on March 22, 2024

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?
   Over, Jin-Si R., 20240705, Structure from motion GCPs, digital surface model, and orthomosaic representing Marconi Beach, Wellfleet, MA on March 22, 2024: data release DOI:10.5066/P14VBPYC, 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/P14VBPYC
   • https://www.sciencebase.gov/catalog/item/662a9b7cd34ea70bd5f0af25

   This is part of the following larger work.
   Over, Jin-Si R., Sherwood, Chris R., and Traykovski, Peter A., 2024, Topographic, bathymetric, and ground control data collected at Marconi Beach, Wellfleet, Massachusetts in March and April 2024.: data release DOI:10.5066/P14VBPYC, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P14VBPYC
   • https://www.sciencebase.gov/catalog/item/662a9abed34ea70bd5f0aea1

   Other_Citation_Details:

   Suggested citation: Over, J.R., Sherwood, C.R., and Traykovski, P.A., 2024, Topographic, bathymetric, and ground control data collected at Marconi Beach, Wellfleet, Massachusetts in March and April 2024: U.S. Geological Survey data release, https://doi.org/10.5066/P14VBPYC.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -69.96480998
   East_Bounding_Coordinate: -69.96185505
   North_Bounding_Coordinate: 41.89494946
   South_Bounding_Coordinate: 41.89078264
   

3. What does it look like?

   https://www.sciencebase.gov/catalog/file/get/662a9b7cd34ea70bd5f0af25?name=2024-016-FA_Marconi_SfM_browse.JPG&allowOpen=true (JPEG)

   (left) Elevation relative to NAVD88-colored image of topography and (right) true color orthomosaic of the field site. Blue flags indicate the location of the ground control points.

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

   Calendar_Date: 22-Mar-2024

   Currentness_Reference:

   ground condition; one day of data collection on March 22, 2024

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

   Geospatial_Data_Presentation_Form: raster and tabular digital data
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the 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: 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 0.001
      Ordinates (y-coordinates) are specified to the nearest 0.001
      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_1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      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?

   2024-016-FA_Marconi_DSM_UTM19N_NAVD88_5cm.tif

   A raster dataset with encoded elevation values of Marconi Beach in Wellfleet, MA on March 22, 2023. Pixel resolution is 5 cm. (Source: USGS)

   Value

   Surface elevation orthometric height NAVD88 (m) using Geoid 2018 in NAD83(2011) UTM Zone 19N (Source: producer defined)

   Value	Definition
   -999	No data

   Range of values
   Minimum:	-0.793
   Maximum:	22.279
   Units:	meters

   2024-011-FA_Marconi_RGBavg_UTM19N_5cm.tif

   Pixel based raster matrix with 3 layers of information for each pixel. (Source: Producer defined)

   Band_1

   Red wavelength band (Source: Agisoft Metashape)

   Range of values
   Minimum:	3
   Maximum:	255

   Band_2

   Green wavelength band (Source: Agisoft Metashape)

   Range of values
   Minimum:	2
   Maximum:	255

   Band_3

   Blue wavelength band (Source: Agisoft Metashape)

   Range of values
   Minimum:	0
   Maximum:	255

   2024-016-FA_Marconi_GCPs.csv

   Ground control point (AeroPoint 2) positions, elevations, and attributes (Source: USGS)

   FAN

   USGS Field Activity Number (Source: USGS)

   Value	Definition
   2024-016-FA	Year, USGS ID, and Field Activity

   Date

   Calendar date of collection (Source: USGS)

   Value	Definition
   20240322	YYYYMMDD

   Point ID

   Unique point identification number. (Source: Processor defined)

   Range of values
   Minimum:	1
   Maximum:	10

   Attributes

   Unique identifier for ground control points. Prefix AERO### refers to the AeroPoints 2 and the last 3 digits of its identifying code. (Source: producer defined) Character string.

   Latitude NAD83[2011]

   Post-processed latitude of AeroPoint 2 position (NAD83[2011]). (Source: USGS)

   Range of values
   Minimum:	41.89122624
   Maximum:	41.89364555
   Units:	decimal degrees

   Longitude NAD83[2011]

   Post-processed longitude of AeroPoint 2 position (NAD83[2011]). (Source: None)

   Range of values
   Minimum:	-69.96340629
   Maximum:	-69.96223365
   Units:	decimal degrees

   Ellipsoid NAD83[2011]

   Post-processed height in meters of AeroPoint in relation to the NAD83(2011) reference ellipsoid. (Source: None)

   Range of values
   Minimum:	-26.023
   Maximum:	-11.205
   Units:	meters

   Northing 19N

   Post-processed interpolated X-coordinate of AeroPoint in NAD83(2011)/UTM Zone 19N. (Source: USGS)

   Range of values
   Minimum:	4638147.013
   Maximum:	4638416.341
   Units:	meters

   Easting 19N

   Post-processed interpolated Y-coordinate of AeroPoint in NAD83(2011)/UTM Zone 19N. (Source: USGS)

   Range of values
   Minimum:	420079.424
   Maximum:	420174.429
   Units:	meters

   Orthometric NAVD88

   Post-processed Z-coordinate of AeroPoint using NAVD88 with Geoid 18 applied. (Source: USGS)

   Range of values
   Minimum:	1.777
   Maximum:	16.595
   Units:	meters

   Xvar mm

   Variance in the X-coordinate from post-processing (Source: producer defined)

   Range of values
   Minimum:	1.2
   Maximum:	8.2
   Units:	millimeters

   Yvar mm

   Variance in the Y-coordinate from post-processing (Source: producer defined)

   Range of values
   Minimum:	1.7
   Maximum:	12.6
   Units:	millimeters

   Zvar mm

   Variance in the Z-coordinate from post-processing (Source: producer defined)

   Range of values
   Minimum:	4.4
   Maximum:	11.1
   Units:	millimeters

   Baseline distance km

   distance of AeroPoint 2 from nearest used processing network base station (Source: Propeller)

   Range of values
   Minimum:	0.04
   Maximum:	12.04
   Units:	kilometers

   Entity_and_Attribute_Overview:

   The filenames of the rasters are formatted as "2024-016-FA_Marconi_product_HCRS_VCRS_resolution.tif", where 2024-016 is the USGS Field activity ID, location is Marconi, product is either DSM or RGBavg, the horizontal coordinate reference system (HCRS) is UTM19N, the vertical coordinate reference system (VCRS) is NAVD88, and resolution is 5 cm. The attributes of the GCP CSV describe each column of information in the file.

   Entity_and_Attribute_Detail_Citation: USGS Field Activity 2024-016-FA
   

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • 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, Woods Hole Coastal and Marine Science Center

   Geographer

   384 Woods Hole Rd.

   Woods Hole, MA
   

   508-548-8700 x2297 (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-2024 (process 1 of 2)

   The ground control points were processed with the following steps:
   1. Ten AeroPoint 2s were deployed evenly spaced across the survey area. AeroPoint 2s were left on for ~3 hours to collect GNSS data.
   2. Once connected to Wifi, the AeroPoint 2 data were uploaded and run through a post-processing kinematic algorithm of the CORS network to get a global accuracy. The data were exported with xyz variances in the horizontal datum NAD83(2011) to produce latitude, longitude, and ellipsoid heights, and then UTM19N and NAVD88 using Geoid 18 was used to produce orthometric heights. These are exported to a CSV file and named 2024-016-FA_Marconi_GCPs.csv.

   Date: Apr-2024 (process 2 of 2)

   DSM and orthomosaic was created in Agisoft Metashape Pro v. 2.1.0 using the following general steps (see Over and others, 2021 for details):
   1. Metashape project was created with imagery (located in larger work citation 2024-016-FA_Marconi_imagery.zip). Photos were aligned at a low accuracy and then GCPs were automatically detected in the point cloud. The ten GCPs were located and location information added using the CSV file from the previous step.
   2. GCP horizontal and vertical accuracy was set to 0.01/0.02 m. The photos were re-aligned with high accuracy (the pixels are not subsampled for increased processing speed) using a keypoint limit of 40,000 and unlimited tie points.
   3. Metashape software refined and optimized, using least squares, the camera positions, GCPs, and lens model using gradual selection and optimization parameters of: Reprojection uncertainty = 20, Projection accuracy = 5, and Reprojection error = 0.3 to minimize the distance between the measured points and the software created points (see Over and others, (2021) for a detailed discussion on these parameters).
   4. A dense point cloud was generated using high-quality (images are not subsampled) and a low frequency filtering algorithm. The dense point cloud was then edited by hand to remove erroneous points before generating a DSM with interpolation disabled.
   5. The DSM was then exported (2024-016-FA_Marconi_DSM_UTM19N_NAVD88_5cm.tif).
   6. A second DSM with interpolation enabled was created and from that surface an orthomosaic using the RGB averaged method was created. The orthomosiac was then exported (2024-011-FA_HOM_RGBavg_UTM19N_5cm.tif).
   7. Products were Adobe deflate compressed and cloud optimized using gdal_translate with the following command: for %i in (.\*.tif) do gdal_translate %i .\%~ni_cog.tif -of COG -stats -co BLOCKSIZE=256 -co COMPRESS=DEFLATE -co PREDICTOR=YES -co NUM_THREADS=ALL_CPUS -co BIGTIFF=YES (v. 3.1.4 accessed October 20, 2020 https://gdal.org/), where i is the name of each GeoTIFF. Person who carried out this activity:
   

   Jin-Si R. Over

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

   Geographer

   384 Woods Hole Rd

   Woods Hole, MA
   

   508-548-8700 x2297 (voice)

   jover@usgs.gov

3. What similar or related data should the user be aware of?
   Over, Jin-Si R., Sherwood, Chris R., and Traykovski, Peter A., 2023, Topographic and bathymetric data, structure from motion imagery, and ground control data collected at Marconi Beach, Wellfleet, Massachusetts in March 2023, U.S. Geological Survey Field Activity 2023-012-FA.: data release DOI:10.5066/P99ST3LT, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P99ST3LT

   Other_Citation_Details: This publication is the survey data of Marconi Beach from 2023.
   

   Over, Jin-Si R., Sherwood, Chris R., Traykovski, Peter A., and Bartlett, Marie K., 2022, Topographic and bathymetric data, structure from motion imagery, and ground control data collected at Marconi Beach, Wellfleet, MA in March 2022, U.S. Geological Survey Field Activity 2022-014-FA: data release DOI:10.5066/P9L1KCQB, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P9L1KCQB

   Other_Citation_Details: This publication is the survey data of Marconi Beach from 2022.
   

   Over, Jin-Si R., Sherwood, Chris R., Traykovski, Peter A., and Marsjanik, Eric E., 2021, Topographic and bathymetric data, sediment samples, structure from motion imagery, and reference mark data collected at Marconi Beach, Wellfleet in winter 2021, U.S Geological Survey Field Activity 2021-022-FA (ver. 2, December 2023): data release DOI:10.5066/P9POZ9VH, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.5066/P9POZ9VH

   Other_Citation_Details: This publication is the survey data of Marconi Beach from 2021.
   

   Over, Jin-Si R., Ritchie, Andrew C., Kranenburg, Christine J., Brown, Jenna A., Buscombe, Daniel D., Noble, Tom, Sherwood, Christopher R., Warrick, Jonathan A., and Wernette, Phillipe A., 2021, Processing coastal imagery with Agisoft Metashape Professional Edition, version 1.6-Structure from motion workflow documentation: Open-File Report 2021-1039, U.S. Geological Survey, Reston, VA.

   Online Links:

   • https://doi.org/10.3133/ofr20211039

   Other_Citation_Details:

   This publication includes the general methodology for processing imagery in Metashape to produce digital surface models and ortho products.

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

1. How well have the observations been checked?
   GCP error in the Metashape project is used to assess overall error in the products. Products are also compared to previous surveys to make sure stable points still align. Additional sources of error such as poor image-to-image point matching due to vegetation or uniform substrate texture or moving objects resulting in poor surface reconstruction may cause localized errors in some portions of the DSM to exceed accuracy estimates.
2. How accurate are the geographic locations?
   The GCPs (n=10) have a theoretical accuracy of 1-2 cm. The horizontal RMSE of the GCPs was xy: 0.008, 0.014 (m). The final products were compared to the previous survey (see cross-reference) and the orthos and DSMs align at stable features.
3. How accurate are the heights or depths?
   The GCPs (n=10) have a theoretical accuracy of 1-2 cm. The vertical RMSE of the GCPs was z: 0.006 (m). The final products were compared to the previous survey at Head of the Meadow (see cross-reference) and orthos and DSMs align at stable features.
4. Where are the gaps in the data? What is missing?
   The DSM provided is not interpolated between data holes. 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?
   The orthomosaic and digital surface model (DSM) are created from GCPs and imagery (see the larger work citation). The extent of the orthomosaic is greater than the DSM because it includes water and edges that do not photogrammetrically reconstruct. All data fall into expected elevation ranges except for points near buildings, the edges, and near water, where the data return is often sparse, noisy, and erroneous. GeoTIFFs are cloud optimized.

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? Files are the SfM products and georeferencing data of Marconi Beach in 2024.
3. What legal disclaimers am I supposed to read?
   Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	2024-016-FA_Marconi_RGBavg_UTM19N_5cm.tif (46.9 MB) is an orthomosaic and 2024-016-FA_Marconi_DSM_UTM19N_NAVD88_5cm.tif (66.8 MB) is an elevation raster. in format GeoTIFF (version 1.0.0) GeoTIFF format Adobe deflate compressed Size: 46.9
     Network links:	https://www.sciencebase.gov/catalog/file/get/662a9b7cd34ea70bd5f0af25 https://www.sciencebase.gov/catalog/item/662a9b7cd34ea70bd5f0af25 https://doi.org/10.5066/P14VBPYC

     Data format:	The CSV file 2024-016-FA_Marconi_GCPs.csv contains ground control data. in format CSV (version Exported from Excel Office 365 16.01) Size: 0.01
     Network links:	https://www.sciencebase.gov/catalog/file/get/662a9b7cd34ea70bd5f0af25 https://www.sciencebase.gov/catalog/item/662a9b7cd34ea70bd5f0af25 https://doi.org/10.5066/P14VBPYC

   • Cost to order the data: none

5. What hardware or software do I need in order to use the data set?
   GIS software capable of reading a GeoTIFF.

Who wrote the metadata?

Dates:

Last modified: 05-Jul-2024

Metadata author:

Jin-Si R. Over

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

Geographer

U.S. Geological Survey

Woods Hole, MA

508-548-8700 x2297 (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)