RGB and thermal imagery, SfM products, and GPS data collected during UAS operations at Marsh Island, New Bedford, MA on July 2nd, 2024

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

Frequently anticipated questions:

What does this data set describe?

Title:
RGB and thermal imagery, SfM products, and GPS data collected during UAS operations at Marsh Island, New Bedford, MA on July 2nd, 2024
Abstract:
Small Uncrewed Aircraft Systems (sUAS) were used to collect aerial remote sensing data over Marsh Island, a salt marsh restoration site along New Bedford Harbor, Massachusetts. Remediation of the site will involve direct hydrological and geochemical monitoring of the system alongside the UAS remote sensing data. On July 2nd, 2024, USGS personnel and interns collected natural (RGB) color and infrared (thermal) images and ground control points. These data were processed to produce a high resolution orthomosaics and a digital surface model. Data collection is related to USGS Field Activity 2024-004-FA and this release only provides the UAS portion.
Supplemental_Information:
For more information about the WHCMSC Field Activity, see https://cmgds.marine.usgs.gov/services/activity.php?fan=2024-004-FA. Images can be viewed or downloaded on the USGS Imagery Data System here https://doi.org/10.5066/P14MGKBY. Note that the bounding coordinates are for the entire area and not individual files.
  1. How might this data set be cited?
    Ackerman, Seth D., and Cramer, Jennifer M., 20241220, RGB and thermal imagery, SfM products, and GPS data collected during UAS operations at Marsh Island, New Bedford, MA on July 2nd, 2024: data release DOI:10.5066/P19TLXVG, U.S. Geological Survey, Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center, Woods Hole, MA.

    Online Links:

    This is part of the following larger work.

    Over, Jin-Si R., Cramer, Jennifer M., Brosnahan, Sandra M., Ackerman, Seth D., and Ganju, Neil Kamal, 2024, Topographic, multispectral, and GPS data collected during uncrewed aircraft system (UAS) operations at Marsh Island, New Bedford, Massachusetts: data release DOI:10.5066/P19TLXVG, U.S. Geological Survey, Reston, VA.

    Online Links:

    Other_Citation_Details:
    Suggested citation: Over, J.R., Cramer, J.M., Brosnahan, S.M., Ackerman, S.D., and Ganju, N.K., 2024, Topographic, multispectral, and GPS data collected during uncrewed aircraft system (UAS) operations at Marsh Island, New Bedford, Massachusetts: U.S. Geological Survey data release, https://doi.org/10.5066/P19TLXVG.
  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -70.91839811
    East_Bounding_Coordinate: -70.91319555
    North_Bounding_Coordinate: 41.65346253
    South_Bounding_Coordinate: 41.64995665
  3. What does it look like?
    https://www.sciencebase.gov/catalog/file/get/66d71e76d34eef5af66ca5ed?name=2024-004-FA_MI_Jul_data_browse.jpg&allowOpen=true (JPEG)
    Data and products of Marsh Island in July 2024: RGB and thermal images, RGB orthomosaic, IR orthomosaic, and structure from motion DEM.
  4. Does the data set describe conditions during a particular time period?
    Calendar_Date: 02-Jul-2024
    Currentness_Reference:
    Ground condition
  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?
    2024004FA_MI_Jul_ImageryLocations.csv
    The CSV file contains the approximate position of the SX10 images at the moment of each capture. (Source: producer defined)
    ImageName
    File names of individual images, see the Process Description for file naming convention. (Source: USGS) Character string.
    GPSDateTime
    Date and UTC time in YYYY:MM:DD HH:MM:ss (Source: Processor defined) Character string.
    Latitude NAD83[2011]
    Latitude (x) of UAS based on time of each image capture. Positive values represent North coordinates. (Source: USGS)
    Range of values
    Minimum:41.650764
    Maximum:41.653183
    Units:decimal degrees
    Longitude NAD83[2011]
    Longitude (y) of UAS based on time of each image capture. Negative values represent West coordinates. (Source: USGS)
    Range of values
    Minimum:-70.918373
    Maximum:-70.913933
    Units:decimal degrees
    Altitude NAVD88
    Altitude of the UAS position at the time of each image capture in NAVD88. (Source: None)
    Range of values
    Minimum:14.223
    Maximum:91.385
    Units:meters
    2024004FA_MI_Jul_AeroPoints.csv
    Ground control point positions, elevations, and attributes (Source: USGS)
    FAN
    USGS Field Activity Number (Source: USGS)
    ValueDefinition
    2024-004-FAYear, USGS ID, and Field Activity
    Date
    Calendar date of collection (Source: USGS)
    ValueDefinition
    20240702YYYYMMDD
    Point ID
    Unique point identification number. (Source: Processor defined)
    Range of values
    Minimum:1
    Maximum:10
    Attributes
    Unique identifier for ground control points. Prefix AP-### refers to AeroPoint and the last 3 digits of its identifying code. (Source: producer defined) Character string.
    Latitude NAD83[2011]
    Post-processed latitude of AeroPoint position (NAD83[2011]). (Source: USGS)
    Range of values
    Minimum:41.65110537
    Maximum:41.65234458
    Units:decimal degrees
    Longitude NAD83[2011]
    Post-processed longitude of AeroPoint position (NAD83[2011]). (Source: None)
    Range of values
    Minimum:-70.91779656
    Maximum:-70.91427484
    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:-28.360
    Maximum:-25.745
    Units:meters
    Northing 19N
    Post-processed interpolated X-coordinate of AeroPoint in NAD83(2011)/UTM Zone 19N. (Source: USGS)
    Range of values
    Minimum:4612814.961
    Maximum:4612952.514
    Units:meters
    Easting 19N
    Post-processed interpolated Y-coordinate of AeroPoint in NAD83(2011)/UTM Zone 19N. (Source: USGS)
    Range of values
    Minimum:340305.354
    Maximum:340600.397
    Units:meters
    Orthometric NAVD88
    Post-processed Z-coordinate of AeroPoint using NAVD88 with Geoid 18 applied. (Source: USGS)
    Range of values
    Minimum:0.830
    Maximum:3.448
    Units:meters
    Xvar mm
    Variance in the X-coordinate from post-processing (Source: producer defined)
    Range of values
    Minimum:1.6
    Maximum:8.8
    Units:millimeters
    Yvar mm
    Variance in the Y-coordinate from post-processing (Source: producer defined)
    Range of values
    Minimum:2.2
    Maximum:12.7
    Units:millimeters
    Zvar mm
    Variance in the Z-coordinate from post-processing (Source: producer defined)
    Range of values
    Minimum:4.2
    Maximum:29.8
    Units:millimeters
    Baseline distance km
    distance of AeroPoint from nearest used processing network base station (Source: Propeller)
    Range of values
    Minimum:0.05
    Maximum:9.50
    Units:kilometers
    2024004FA_MI_Jul_SX10_DSM_5cm.tif
    A cloud-optimized digital surface model created from SX10 RGB images using photogrammetry with encoded elevation values. Pixel resolution is 5 cm. No-data value is –3.4028e+38. (Source: USGS)
    Value
    Surface elevation orthometric height NAVD88 (m) using Geoid 2018 in NAD83(2011) UTM Zone 19N. (Source: producer defined)
    Range of values
    Minimum:-2.640
    Maximum:21.189
    Units:meters
    2024004FA_MI_Jul_SX10_RGBavg_Ortho_5cm.tif
    True-color (RGB) cloud optimized GeoTIFF of Marsh Island. (Source: USGS)
    Band_1
    Red wavelength band (Source: Agisoft Metashape)
    Range of values
    Minimum:0
    Maximum:255
    Band_2
    Green wavelength band (Source: Agisoft Metashape)
    Range of values
    Minimum:0
    Maximum:255
    Band_3
    Blue wavelength band (Source: Agisoft Metashape)
    Range of values
    Minimum:0
    Maximum:255
    2024004FA_MI_Jul_SX10_IR_Ortho_10cm.tif
    Thermal infrared cloud optimized GeoTIFF of Marsh Island. (Source: USGS)
    Band_1
    Thermal infrared band (Source: Agisoft Metashape)
    Range of values
    Minimum:5.91
    Maximum:50.00
    Units:Celsius
    Entity_and_Attribute_Overview:
    The filenames are formatted as "2024004FA_MI_Jul_sensor/product_ resolution.*** ", where 2024004 is the USGS Field activity ID, location is Marsh Island (MI), Jul is the month, sensor is Skydio X10 (SX10), and products include true color (RGB) and thermal infrared (IR) orthomosaics (ortho), and digital surface model (DSM). The horizontal coordinate reference system for all products is NAD83(2011)/UTM19N, the vertical coordinate reference system is NAVD88.
    Entity_and_Attribute_Detail_Citation: USGS Field Activity 2024-004-FA

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Seth D. Ackerman
    • Jennifer M. Cramer
  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
    Geographer
    384 Woods Hole Rd.
    Woods Hole, MA

    508-548-8700 x2297 (voice)
    jover@usgs.gov

Why was the data set created?

The imagery and products were produced to help the sites conservation partnership evaluate the baseline conditions of the site, with future data collections planned to monitor landscape change from remediation efforts and potential storm impacts.

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: 02-Jul-2024 (process 1 of 5)
    GROUND CONTROL: Ten AeroPoint GCPs were spaced out over the field site and left on for at least two hours to collect GNSS data. After collection and connected to Wifi, the AeroPoint data were uploaded and run through a post-processing kinematic algorithm of the CORS network to get a global accuracy. Internal accuracy is reported in xyz variance and with a baseline distance. The data were exported in the horizontal datum NAD83(2011) to produce latitude, longitude, and ellipsoid heights, and then UTM19N and vertical datum NAVD88 using Geoid 18 was used to produce easting and northing and orthometric heights. These were exported to a CSV file and named 2024004FA_MI_Jul_AeroPoints.csv.
    Date: 02-Jul-2024 (process 2 of 5)
    UAS FLIGHTS: The Skydio X10 is a small UAS with an integrated VT300-L camera system. The radiometric thermal camera is a FLIR Boson+ with less than 30 millikelvin sensitivity. The Skydio X10 also has two RGB cameras, one has a 50 degree field of view (narrow) and the other has a 93 degree field of view (wide). A single flight in auto mapping mode was flown at 85 meters with 70% desired sidelap and overlap and 0.67 cm ground sampling distance. The UAS was flown at 5 m/s using the narrow camera and thermal camera. Two sets of thermal images are taken, but only the set with the radiometric data (SX10r) is provided, as the second set is redundant. Note that all images are automatically tagged by the internal GPS in WGS84 + EGM96 but the positions have been converted to NAD83(2011) and NAVD88 geoid 18 in the imagery locations file (2024004FA_MI_Jul_ImageryLocations.csv) and this is accounted for when transforming to NAD83(2011)/UTM19N and NAVD88 Geoid 18 in the products.
    Date: 20-Jul-2024 (process 3 of 5)
    RAW IMAGERY: The SkyDio images (thermal images are radiometric JPEGs (RJPEG) and RGB images are regular JPEGs) were processed to add additional information required by the USGS to the EXIF headers using ExifTools (https://exiftool.org/, version: 12.06), and the files were renamed to a unique identifier using Namexif (http://www.digicamsoft.com/softnamexif.html, version 2.1) to avoid any possibility of duplicate names. These steps are described here. 1. ExifTools was used to tag each photo headers following the Imagery Data System EXIF Guidance. Attributes (e.g. Credit, Copyright, UsageTerms, ImageDescription, Artist, etc) were stored in a csv file and written to each image with the command:' exiftool -csv="C:\directory\name\EXIF.csv" C:\directory\name\of\photos *.JPG ' To read out the photo information to a csv when in the directory with the photos the command is: exiftool -csv *.JPG > .\allheaders_out.csv 2. All the images were renamed with Namexif (https://us.digicamsoft.com/softnamexif.html v 2.1 accessed April 2020) to ensure unique filenames and compliance with the USGS Coastal and Marine Hazards and Resources Program's best practices for image naming convention. Images were renamed with the field survey ID prefix; flight number, and ID that distinguishes USGS cameras by make/camera number, the image acquisition date, coordinated universal time (UTC) in ISO8601 format, and a suffix with the original image name. For example, image name '2024004FA_f01SX10r_20240702T165822Z_S#######', 2024004FA is the field activity ID, f01 is the flight number, SX10r is a Skydio X10 radiometric image, 20240702 is the UTC date in the format YYYYMMDD, and a 'T' is used to separate UTC date from UTC time in format HHMMSS followed by a Z. The S######## is the original raw photo name appended to the end of the new filename.
    Date: 01-Sep-2024 (process 4 of 5)
    PHOTOGRAMMETRY: The products were created in Agisoft Metashape Pro v. 2.0.1 using the following general steps (see Over and others, 2021 for a more detailed SfM methodology explanation and https://support.skydio.com/hc/en-us/articles/27236378437019-Scan-reconstruction-best-practices-with-Skydio-X10 for processing the SX10 images): 1. A project was created in Metashape and thermal and RGB imagery was imported. 2. Photos were aligned at a low accuracy and then GCPs were automatically detected in the point cloud. GCP positions (2024004FA_MI_Jul_AeroPoints.csv) were added to the project in the reference systems NAD83(2011)/UTM Zone 19N and NAVD88 (geoid 18). The horizontal and vertical accuracies for the GCPs were set to 0.01/0.02 m, respectively, and the camera position accuracy for the images was set to 10 m. The photos were then re-aligned with high accuracy (the pixels were not subsampled) using a keypoint limit of 40,000 and unlimited tie points. 3. The alignment process matched pixels between images to create point clouds and put the imagery into a relative spatial context using the GCPs. The resultant point clouds were filtered using one iteration of the 'Reconstruction uncertainty' filter at a level of 14, one iteration of the 'Projection accuracy' filter at a level of 4, and three iterations of the 'Reprojection accuracy' filter to get to a level of 1. With each filter, iteration points are selected, deleted, and then the camera model was optimized to refine the focal length, cx, cy, k1, k2, k3, p1, and p2 camera model coefficients. 4. At this point, multiple ‘chunks’ were created so that a high-quality dense cloud with a low-frequency filtering algorithm could be made for both the radiometric and RGB images. The dense point cloud was then edited by visual inspection to remove points with a low confidence near the edges and near water bodies. 5. A DSM is built from each dense point cloud and then an RGB averaged orthomosaic is built from the DSM with refined seamlines. The RGB DSM and orthomosaic were exported at 5 cm resolution (2024004FA_MI_Jul_SX10_DSM_5cm.tif and 2024004FA_MI_Jul_SX10_RGBavg_Ortho_5cm.tif). The thermal orthomosaic was converted from Kelvin to Celsius using the band math (0.01*thermal_band)-273.15 and exported as a single band raster at 10 cm resolution keeping only values within the ranges of 5 and 50 to remove outlier values (2024004FA_MI_Jul_SX10_IR_Ortho_10cm.tif).
    Date: 01-Sep-2024 (process 5 of 5)
    CLOUD OPTIMIZATION: All products were DEFLATE compressed and turned into a cloud-optimized geoTIFFs (COG) using gdal_translate with the following command: for %i in (.\*.tif) do gdal_translate %i .\cog\%~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 section. Person who carried out this activity:
    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)
    jover@usgs.gov
  3. What similar or related data should the user be aware of?
    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:

    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?
    The horizontal and vertical accuracy of the products (2024004FA_MI_Jul_SX10_DSM_5cm.tif and 2024004FA_MI_Jul_SX10_RGBavg_5cm.tif) were assessed using the AeroPoint ground control points (GCPs). It should also be noted that accuracy estimates of the products are for areas of bare ground or low vegetation where GCPs were placed. Additional sources of error, such as moving objects, may cause accuracy estimates to exceed estimates in localized portions of the products. The accuracy of the infrared temperature values in the product (2024004FA_MI_Jul_SX10_IR_Ortho_10cm.tif) were not assessed, users are advised to do their own quality control.
  2. How accurate are the geographic locations?
    The horizontal accuracy of the SfM products was assessed against positions of the AeroPoints and tarps, where the horizontal root mean square error (RMSE) of the GCPs as reported from the Metashape project are xy 0.048/0.088 m.
  3. How accurate are the heights or depths?
    The vertical accuracy of the SfM DSM was assessed against positions of the AeroPoints and tarps, where the vertical RMSE of the GCPs as reported from the Metashape project is 0.029 m.
  4. Where are the gaps in the data? What is missing?
    Imagery: The SX10 narrow angle camera and thermal camera triggered every 2 seconds. Images at take-off and landing were removed. All of these removed images can account for the non-consecutive original file names and results in a total of 655 SX10 images. Products: GeoTIFF products are cloud-optimized and deflate compressed.
  5. How consistent are the relationships among the observations, including topology?
    There was one UAS flight and five AeroPoint GCPs. The flight (18 min) used the Skydio X10 (SX10) to collect RGB images (SX10c) and radiometric images (SX10r). The images were processed using structure from motion (SfM) to produce a digital surface model (DSM), a true-color (RGBavg) orthomosaic, and an infrared or thermal orthomosaic. All elevation data fall into expected ranges of a low-lying coastal marsh. Images 2024004FA_f01SX10c_20240702T151649Z_S1001886.JPG through 2024004FA_f01SX10c_20240702T151841Z_S1001916.JPG are not for photogrammetry processing, rather they are photos of the field site and field crew.

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 Public domain (CC0-1.0) data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the source of this information. These data are not intended for navigational use.
  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? Aerial imaging and mapping of Marsh Island with the Skydio X10 produced imagery and derivative photogrammetry products with the use of AeroPoint GCPs.
  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. Not for navigational use.
  4. How can I download or order the data?

Who wrote the metadata?

Dates:
Last modified: 20-Dec-2024
Metadata author:
Jin-Si R. Over
U.S. Geological Survey, Northeast Region
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)
This page is <https://cmgds.marine.usgs.gov/catalog/whcmsc/SB_data_release/DR_P19TLXVG/2024004FA_MI_Jul_metada.faq.html>
Generated by mp version 2.9.51 on Fri Dec 20 15:45:42 2024