U.S. Geological Survey 2018 1.0 raster digital data data release DOI:10.5066/P9XQYCD0 Woods Hole Coastal and Marine Science Center, Woods Hole, MA U.S. Geological Survey, Coastal and Marine Geology Program https://doi.org/10.5066/P9XQYCD0 https://www.sciencebase.gov/catalog/item/5b1ee156e4b092d965254a4b Christopher R. Sherwood Sandra M. Brosnahan Seth D. Ackerman Jonathan Borden Ellyn T. Montgomery Elizabeth A. Pendleton Emily J. Sturdivant 2018 1.0 data release DOI:10.5066/P9XQYCD0 Reston, VA U.S. Geological Survey Suggested citation: Sherwood, C.R., Brosnahan, S.M., Ackerman, S.D., Borden, Jonathan, Montgomery, E.T., Pendleton, E.A., and Sturdivant, E.J., 2018, Aerial imagery and photogrammetric products from unmanned aerial systems (UAS) flights over the Lake Ontario shoreline at Sodus Bay, New York, July 12 to 14, 2017: U.S. Geological Survey data release, https://doi.org/10.5066/P9XQYCD0. https://doi.org/10.5066/P9XQYCD0 https://www.sciencebase.gov/catalog/item/5b0800a7e4b0ac450c99d116 Low-altitude (80-100 meters above ground level) digital images were obtained from a camera mounted on a 3DR Solo quadcopter, a small unmanned aerial system (UAS), along the Lake Ontario shoreline in New York during July 2017. These data were collected to document and monitor effects of high lake levels, including shoreline erosion, inundation, and property damage in the vicinity of Sodus Bay, New York. This data release includes images tagged with locations determined from the UAS GPS; tables with updated estimates of camera positions and attitudes based on the photogrammetric reconstruction; tables listing locations of the base stations, ground control points, and transect points; geolocated, RGB-colored point clouds; orthomosaic images; and digital elevation models for each of the survey regions. Collection of these data was supported by the Federal Emergency Management Agency, the State of New York Departments of State and Environmental Conservation, and the USGS Coastal and Marine Geology Program and was conducted under USGS field activity number 2017-042-FA. The gridded DEM surface estimates the elevation of the land surface at mid-day low-tide on 14 July, 2017 in the Greig Street study area. It was created to demonstrate the use of structure-from-motion (SfM) for shoreline research and to provide a means to measure the accuracy of the elevation measured through SfM photogrammetry. It is released to provide an elevation dataset that is more accessible than the LAZ elevation point cloud for the general user. For more information about this field activity, see https://cmgds.marine.usgs.gov/fan_info.php?fan=2017-042-FA. 20170714 ground condition Complete None planned -76.986433 -76.969400 43.273290 43.265003 USGS Metadata Identifier USGS:5b1ee156e4b092d965254a4b None U.S. Geological Survey USGS Coastal and Marine Geology Program CMGP Woods Hole Coastal and Marine Science Center WHCMSC State of New York Department of State State of New York Department of Environmental Conservation Federal Emergency Management Agency shoreline lake level 3DR Solo quadcopter Ricoh GRII low-altitude aerial imagery aerial imagery shoreline photographs photographs photos UAS Unmanned aerial system lakeshore digital elevation model DEM GeoTIFF raster field activity number 2017-042-FA USGS Thesaurus remote sensing topography digital elevation models ISO 19115 Topic Category geoscientificInformation inlandWaters location elevation None USA Great Lakes New York Lake Ontario Sodus, NY Sodus Point Sodus Bay Greig Street none Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset. U.S. Geological Survey Sandra Brosnahan Physical Scientist mailing and physical address

384 Woods Hole Road

Woods Hole Massachusetts 02543-1598 508-548-8700 x2265 508-457-2310 sbrosnahan@usgs.gov https://www.sciencebase.gov/catalog/file/get/5b1ee156e4b092d965254a4b/?name=2017042FA_GreigSt_DEM_browse.jpg Browse graphic of a portion of the DEM generated from photogrammetry and low-altitude aerial images obtained with unmanned aerial systems (UAS). JPEG All data were handled in a consistent manner. Photoscan software determines the photos used in the construction of the products (Point Cloud, DEM and Orthomosaic) based on the ability to align the photo and the usability of valid tie points within an image, and some photos of the take-off and landing were omitted by the processor during the import data phase. A tie point represents a point that the software determine to be common from one photo to the next. The camera locations CSV file in the larger work citation indicates which photos were used to create the final products. The final point cloud used to construct this dataset was checked for accuracy by rotating the point cloud to view from multiple angles to ensure that obvious spurious points do not cause artifacts in the derivative products (DEM and Orthomosaic). This DEM was created from the filtered tie-points of the dense point cloud using the Agisoft Photoscan Professional (v. 1.3.2) photogrammetry software. Through a standardized filtering process, spurious points from the dense point cloud were eliminated and the remaining point cloud was used to generate a digital elevation model. The completed Photoscan project for Greig Street, from which this DEM was created, used 1235 of the original 1640 images and contained more than 252 million points. The unedited point cloud and the orthomosaic are available in the larger work citation. Horizontal positions of individual points for the DEM were calculated by photogrammetric software and ground control points. There are several sources of potential error that affect the horizontal accuracy: 1. The horizontal error estimate provided by Agisoft Photoscan for the Greig Street project as a result of alignment, optimization, and ground control processing procedures is 9.91 cm. This value is an RMS estimate of positional error at discrete locations within the orthomosaic. 2. Ground control points were collected using a Spectra model SP80 GNSS receiver set to record XY locations with the national adjustment of 2011 (NAD83(2011) UTM zone 18N EPSG::6347), which differs from the Photoscan project coordinate system (NAD83/UTM zone 18N (EPSG::26918)). This difference may introduce an average additional 0.9 cm horizontally at the 95% confidence level according to the National Geodetic Survey (https://www.ngs.noaa.gov/web/surveys/NA2011/). 3. Additionally, an assessment of repeated survey sites including transect points and ground control points, using the same equipment by the USGS Aerial Imagery and Mapping (AIM) group estimates an accuracy of the ground control point locations of 1.76 cm (horizontal) and 0.54 cm (vertical). The combination of the potential horizontal error is on the order of 12.35 cm for the Greig Street products. Although some portions of the map may contain much larger errors, up to 2 m horizontally. The horizontal coordinate system for the Greig Street Point Cloud, DEM and Orthomosaic is NAD83/UTM zone 18N (EPSG::26918). It is also important to note: The UAS image locations are derived from a mRo GPS (u-Blox Neo-M8N / 3DR SOLO Upgrade), located on the UAS, which receives signals from GPS and GLONASS satellites in WGS84 (G1150) EPSG::7660. This location information is used by the Photoscan software to help with the initial alignment, however after photo alignment, these location data have no bearing on the project or the derivative product. Therefore the positional accuracy and potential errors of the GPS data attached to the input photographs is not propagated to the Photoscan project and therefore does not contribute to the overall horizontal accuracy of the products (Point Cloud, DEM and Orthomosaic). Vertical positions of individual points for the point cloud were calculated by photogrammetric software and ground control points. There are several sources of potential error that affect the vertical accuracy: 1. The vertical error estimate provided by Agisoft Photoscan for the Greig Street project as a result of alignment, optimization, and ground control processing procedures is 7.23 cm. This value is an RMS estimate of positional error at discrete locations within the orthomosaic. 2. Ground control points were collected using a Spectra model SP80 GNSS receiver that was receiving real-time differential corrections from a GNSS base station established in Sodus Bay NY. The Z heights were reference to the NAVD88 vertical datum. An assessment of repeated survey sites using the same equipment by the USGS Aerial Imagery and Mapping group estimates a potential accuracy error of the ground control point locations of 1.76 cm (horizontally) and 0.54 cm (vertically). The vertical datum for the Greig Street Point Cloud, DEM and Orthomosaic is NAVD88 (meters). It is also important to note: The UAS image locations are derived from a mRo GPS (u-Blox Neo-M8N / 3DR SOLO Upgrade), located on the UAS, which receives signals from GPS and GLONASS satellites in WGS84 (G1150) EPSG::7660. This location information is used by the Photoscan software to help with the initial alignment, however after photo alignment, these location data have no bearing on the project or the derivative product. Therefore the positional accuracy and potential errors of the GPS data attached to the input photographs is not propagated to the Photoscan project and therefore does not contribute to the overall vertical accuracy of the products (Point Cloud and DEM). U.S. Geological Survey unpublished material raster digital images 20170712 20170714 ground condition; images were obtained between 20170712 and 20170714. geotagged aerial digital images These are the images geotagged in the field using Mission Planner Software (version 1.3.49) and used to produce the subsequent photogrammetric products. The images available from the larger work citation of this data release are the same images, however they were renamed and geotagged using exiftools (version 10.93). U.S. Geological Survey 2018 available from the Larger Work citation of this dataset (Suggested citation: Sherwood, C.R., Brosnahan, S.M., Ackerman, S.D., Borden, Jonathan, Montgomery, E.T., Pendleton, E.A., and Sturdivant, E.J., 2018, Aerial imagery and photogrammetric products from unmanned aerial systems (UAS) flights over the Lake Ontario shoreline at Sodus Bay, New York, July 12 to 14, 2017: U.S. Geological Survey data release, https://doi.org/10.5066/P9XQYCD0.) text data files 20170712 20170714 ground condition; ground control points were obtained between 20170712 and 20170714. GCPs The ground control points (GCPs; not transect points -- see metadata for more information) were used to geolocate the photogrammetric products. Digital elevation models (DEM) for the Lake Ontario projects were constructed using photogrammetry software (Agisoft Photoscan Professional v. 1.3.2) and digital images taken approximately 80 and 100 m above the ground on July 10 - 14, 2017, with a Ricoh GRII digital camera mounted in a 3DR Solo quadcopter operated the U.S. Geological Survey. This DEM is the product from one of several photogrammetry projects from field activity 2017-042-FA. Four projects were used for flights in the vicinity of Sodus Bay on July 12, 13, and 14, 2017 (Lake Bluffs, Charles Point, Sodus North, and Greig Street). The projects combined images with ground control points to produce geolocated, colored (red-green-blue schema) point clouds. This DEM, for the Greig Street project, was created using a standard processing flow as described in the processing step below. 201709 U.S. Geological Survey, Woods Hole Coastal and Marine Science Center Christopher R. Sherwood Research Oceanographer mailing and physical address

384 Woods Hole Road

Woods Hole Massachusetts 02543 U.S.A. 508-548-8700 x2269 508 457 2310 csherwood@usgs.gov The following steps make up the processing flow for creating digital elevation models from UAS flights: 1. Geotagged images (see source citation) containing useful imagery from the survey area were imported into Agisoft Photoscan Professional v. 1.3.2 software using the “Add photos…” tool. Photos taken before and immediately after takeoff, photos taken immediately prior to and after landing, and photos with 100% water were not loaded into the project. Project coordinate system is set to EPSG::7660 WGS84 (G1150) geocentric coordinate system. 2. Using ”Convert”, the coordinate system of the images (called “cameras” in Photoscan) was converted from native latitude/longitude WGS84 (G1150) coordinate system to meters in NAD83/UTM zone 18N (EPSG::26918). 3. The photos were processed through an initial alignment and optimization procedure using the following settings: Alignment - Accuracy: “High”; Pair selection: “Reference”; Key point limit: 80,000; Tie point limit; 0 (unlimited). Adaptive camera model fitting option was selected. Optimization - Lens-calibration parameters f, cx, cy, k1, k2, k3, p1, and p2 were included; b1, b2, and higher-order parameters k4, p3, and p4 were not. 4. The sparse point cloud (also known as tie points; created as a result of photo alignment and optimization) was edited using an iterative error-reduction procedure to filter the data. This was done in several iterations of a process called "Gradual Selection" to first to reduce reconstruction uncertainty (to a unitless value of 10) and then projection accuracy (to a weighted value of 3). 5. Ground control points were created by first letting the software automatically detect markers where it finds all of the 4-ft square black/white targets deployed (false targets that are sometimes detected were manually deleted). The automatically-generated marker labels were manually changed to match the names in the survey notes and GCP location files. 6. "Import markers” was used to load the GCP location files, which assigned coordinates (northing, easting, and elevation in UTM Zone 18 North meters in NAD83 and NAVD88 coordinate systems) from the location file to the detected markers. The locations of auto-detected markers were retained. 7. Another round of "Gradual Selection" was done to reduce the reprojection error (to a value of 0.3 pixels, unless more than 10% of the points would be removed). 8. A dense point cloud was then created with the parameters "High" quality and “Aggressive” depth filtering. 9. A DEM was created with Global Mapper (v. 19.0) using average binning method with a resolution of 0.05. Elevation points below 72.0 meters were filter out before gridding, and interpolation was set to 'loose' at '75'. 10. The DEM was exported in GeoTIFF format (2017-07-10_GreigSt_DEM_5cm.tif) along with a world file (tfw), then both were renamed to the AIM data release filenaming standard (e.g. 2017042FA_GreigSt_DEM.tif). 20170913 U.S. Geological Survey, Woods Hole Coastal and Marine Science Center Christopher R. Sherwood Research Oceanographer mailing and physical address

384 Woods Hole Road

Woods Hole Massachusetts 02543 U.S.A. 508-548-8700 x2269 508 457 2310 csherwood@usgs.gov Added keywords section with USGS persistent identifier as theme keyword. 20200810 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543-1598 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov Raster Pixel 37240 39060 Universal Transverse Mercator 0.999600 -75.00000 0.000 500000.0000 0.0000 coordinate pair 0.05 0.05 meters North American Datum of 1983 Geodetic Reference System 80 6378137.000000 298.257222101 North American Vertical Datum of 1988 (NAVD88) 0.00001 meters Explicit elevation coordinate included with horizontal coordinates There are no attributes associated with this GeoTIFF however the pixel values of the 32-bit image are elevation values as exported from Agisoft Photoscan. The "no data" value is set to -32767. Data values represent elevation in meters referenced to NAVD88. Note the full precision of the elevation as exported from the Agisoft Photoscan software is 0.00001 m although that is several orders of magnitude finer than the accuracy of the data. The elevation values range from 33.7 to 109.0 meters relative to NAVD88. U.S. Geological Survey U.S. Geological Survey - ScienceBase mailing and physical address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov This data release contains a DEM in 32-bit floating point GeoTIFF format (2017042FA_GreigSt_DEM.tif), the world file (2017042FA_GreigSt_DEM.tfw). FGDC CSDGM metadata (2017042FA_GreigSt_DEM.xml) accompanies the data. 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 USGS 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. GeoTIFF Agisoft Photoscan Professional v. 1.3.2 GeoTIFF 32-bit floating point GeoTIFF image DEM in 32-bit floating point GeoTIFF image at 0.05 meter resolution, world file and the associated metadata. 1052 https://www.sciencebase.gov/catalog/item/5b1ee156e4b092d965254a4b https://www.sciencebase.gov/catalog/file/get/5b1ee156e4b092d965254a4b https://doi.org/10.5066/P9XQYCD0 To download the data, it is recommended that you go to the page containing the data and take advantage of the large file handler. The first link is to the page containing the data. The second is a direct link to download all data available from the page as a zip file. And the final link is to the publication landing page. none To utilize these data an image processing or GIS software package capable of viewing a 32-bit Floating Point GeoTIFF image. Standard image viewing software cannot translate the elevation data from 32-bit floating point GeoTIFF image. 20240319 U.S. Geological Survey Sandra Brosnahan Physical Scientist mailing and physical address

384 Woods Hole Road

Woods Hole Massachusetts 02543-1598 508-548-8700 x2265 508-457-2310 whsc_data_contact@usgs.gov The metadata contact email address is a generic address in the event the person is no longer with USGS. (updated on 20240319) FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998