Metadata: Identification_Information: Citation: Citation_Information: Originator: Christine J. Kranenburg Originator: Jenna A. Brown Originator: Stephen T. Bosse Originator: P. Soupy Dalyander Publication_Date: 20210610 Title: Time Series of Structure-from-Motion Products - RGB Orthomosaics: Little Dauphin Island and Pelican Island, Alabama, September 2018 to April 2019 Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: U.S. Geological Survey Data Release Issue_Identification: doi:10.5066/P9I6BP66 Publication_Information: Publication_Place: St. Petersburg, Florida Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9I6BP66 Description: Abstract: Aerial imagery acquired with a small unmanned aircraft system (sUAS), in conjunction with surveyed ground control points (GCP) visible in the imagery, can be processed with structure-from-motion (SfM) photogrammetry techniques to produce high-resolution orthomosaics, three-dimensional (3D) point clouds and digital elevation models (DEMs). This dataset, prepared by the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center (SPCMSC), provides UAS survey data products consisting of red-green-blue (RGB) orthomosaics produced from imagery collected at Little Dauphin Island and Pelican Island, Alabama, from September 2018 to April 2019 in order to develop integrated models linking geomorphology, habitat characteristics, and non-breeding shorebird species usage. Photogrammetry software was used to perform SfM processing on low-altitude digital aerial imagery acquired with a 3DR Solo UAS quadcopter equipped with a Ricoh GR II digital camera and MicaSense RedEdge 3 multispectral camera, using surveyed temporary targets (black and white, 4-square checked pattern) distributed uniformly throughout the UAS flight operations area as GCPs. The following SfM products are produced for each UAS survey over the northern half of Little Dauphin Island and all of Pelican Island: * georeferenced red-green-blue (RGB) orthomosaic image with 5-centimeter (cm) resolution * georeferenced multispectral (MS) orthomosaic image with 5-cm resolution * DEM with 5-cm horizontal resolution * 3D RGB-colored point cloud All horizontal data are provided in the Universal Transverse Mercator (UTM) projected coordinate system, Zone 16 North (16N), referenced to the North American Datum of 1983 (NAD83(2011)), and elevation is referenced to the North American Vertical Datum of 1988 (NAVD88), GEOID12B. Purpose: These SfM products were produced from aerial images collected at Little Dauphin and Pelican Islands, Alabama, from September 2018 to April 2019, in order to develop integrated models linking geomorphology, habitat characteristics, and non-breeding shorebird species usage. Supplemental_Information: These data were collected by the USGS Coastal and Marine Hazards and Resources Program under the following USGS field activity numbers (FANs), and the associated field activity web pages contain additional information regarding the field activity: 09/2018 FAN: 2018-352-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-352-FA ; 11/2018 FAN: 2018-362-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-362-FA ; 12/2018 FAN: 2018-370-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-370-FA ; 02/2019 FAN: 2019-306-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-306-FA ; 03/2019 FAN: 2019-311-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-311-FA ; 04/2019 FAN: 2019-317-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-317-FA . Time_Period_of_Content: Time_Period_Information: Multiple_Dates/Times: Single_Date/Time: Calendar_Date: 20180912 Single_Date/Time: Calendar_Date: 20180913 Single_Date/Time: Calendar_Date: 20181115 Single_Date/Time: Calendar_Date: 20181116 Single_Date/Time: Calendar_Date: 20181217 Single_Date/Time: Calendar_Date: 20181218 Single_Date/Time: Calendar_Date: 20181219 Single_Date/Time: Calendar_Date: 20190214 Single_Date/Time: Calendar_Date: 20190215 Single_Date/Time: Calendar_Date: 20190312 Single_Date/Time: Calendar_Date: 20190415 Single_Date/Time: Calendar_Date: 20190416 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -88.12889537 East_Bounding_Coordinate: -88.10731142 North_Bounding_Coordinate: 30.28187897 South_Bounding_Coordinate: 30.23092080 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:f54aadd3-551d-49a2-a26e-007f2f2b22c3 Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: structure from motion Theme_Keyword: remote sensing Theme_Keyword: aerial photography Theme_Keyword: geospatial datasets Theme_Keyword: coastal processes Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: CMGP Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: St. Petersburg Coastal and Marine Science Center Theme_Keyword: SPCMSC Theme_Keyword: unmanned aircraft systems Theme_Keyword: UAS Theme_Keyword: orthomosaics Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: imageryBaseMapsEarthCover Theme_Keyword: oceans Place: Place_Keyword_Thesaurus: Geographic Names Information Service (GNIS) Place_Keyword: Alabama Place_Keyword: Mobile County Place_Keyword: Dauphin Island Place_Keyword: Pelican Island Access_Constraints: None Use_Constraints: USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator of the dataset and in products derived from these data. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Christine J. Kranenburg Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Address: Address_Type: mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: ckranenburg@usgs.gov Data_Set_Credit: Data collection was funded by the U.S. Geological Survey. We would like to thank the following people for their contribution to the data collection efforts: Nicholas Enwright, Brett Patton, Chelsea Stalk, Nancy DeWitt and Sara Zeigler of the USGS, and Spencer Stelly of Stelly Consulting. Cross_Reference: Citation_Information: Originator: Kranenburg, C.J. Originator: Brown, J.A. Originator: Sturdivant, E.J. Originator: Stalk, C.A. Originator: Pendleton, E.A. Originator: Ackerman, S.D. Publication_Date: 2021 Title: Time Series of True Color Aerial Imagery from Small Unmanned Aircraft Systems: Little Dauphin Island & Pelican Island, Alabama, September 2018 – April 2019 Series_Information: Series_Name: U.S. Geological Survey Data Release Issue_Identification: Unknown Online_Linkage: Unknown Cross_Reference: Citation_Information: Originator: Goncalves, J.A. Originator: Henriques, R. Publication_Date: 2015 Title: UAV photogrammetry for topographic monitoring of coastal areas Series_Information: Series_Name: ISPRS Journal of Photogrammetry and Remote Sensing Issue_Identification: vol. 104 Online_Linkage: https://doi.org/10.1016/j.isprsjprs.2015.02.009 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The horizontal and vertical measurements of the surface models were compared against global positioning system measurements of fixed features covered by the survey. Logical_Consistency_Report: All data fall within expected ranges. Completeness_Report: This dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The SfM-based geospatial products have an overall horizontal root-mean-square error (RMSE) of 3.4 cm, determined by comparing the horizontal position of the surveyed temporary check points (4-square, black and white, checkerboard targets) and the corresponding horizontal positions digitized in the orthomosaic, for all surveys. Lineage: Process_Step: Process_Description: The SfM products were created for each UAS survey date individually, using the RGB digital negative (DNG) photos (Kranenburg and others, 2021). The complete set of photos was imported into Agisoft Photoscan (versions 1.3.5 - 1.5.5), along with corresponding GCP reference information, and each flight was put into separate camera calibration groups. Photos were aligned at high accuracy, with a keypoint limit of 50,000 and unlimited tiepoints. Camera positions and the lens model were refined using three statistical metrics: reconstruction uncertainty, projection accuracy, and reprojection error with threshold values of 10, 2.6-3.0, and 0.3 respectively. Once the photo positions and lens models were optimized, dense point clouds were generated with Photoscan (Goncalves and Henriques, 2015) using the high quality and moderate filtering settings. The dense point clouds were then used to generate DEMs; note that the DEM represents the elevation of the surface as viewed from above (for example, tops of buildings and vegetation), and does not represent the bare earth surface. Finally, the raw photographs and DEM were combined to produce the orthomosaics which were exported in GeoTIFF file format at 5 cm resolution. Process_Date: 20190827 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Christine J. Kranenburg Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Position: Cartographer Contact_Address: Address_Type: mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: ckranenburg@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 16N Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -87 Latitude_of_Projection_Origin: 0.0 False_Easting: 500000.0 False_Northing: 0.0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.001 Ordinate_Resolution: 0.001 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257222101 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: The RGB orthomosaic is a 4-band (red/green/blue/alpha) raster file, with values of each band ranging from 0 to 255, in GeoTIFF format. No-data values are represented by a value of 0 in band 4 (alpha channel). Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Person: SPCMSC Data Management Group Contact_Address: Address_Type: mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: gs-g-spcmsc_data_inquiries@usgs.gov Resource_Description: These data are available in GeoTIFF format contained in a single ZIP file of SfM products per UAS survey. The RGB orthomosaic files are named with the following convention: yyyy-mm-IslandName -ortho-rgb-5cm.tif where yyyy-mm represents the survey date as year (yyyy) and month (mm); IslandName can have a value of either LittleDauphinIsland or PelicanIsland; and ‘ortho-rgb-5cm’ is used to designate the dataset as a 5-cm resolution RGB orthomosaic. Distribution_Liability: This publication was prepared by an agency of the United States Government. Although these data were processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: GeoTIFF Format_Information_Content: The .zip file contains SfM products per UAS survey, including the orthomosaics saved as .tif files. Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9I6BP66/data/201809_PelicanIsland_SfMProducts.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9I6BP66/data/201811_PelicanIsland_SfMProducts.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9I6BP66/data/201812_PelicanIsland_SfMProducts.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9I6BP66/data/201902_PelicanIsland_SfMProducts.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9I6BP66/data/201904_PelicanIsland_SfMProducts.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9I6BP66/data/201812_LittleDauphinIsland_SfMProducts.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9I6BP66/data/201903_LittleDauphinIsland_SfMProducts.zip Access_Instructions: Data can be downloaded as a zipped file from the Network_Resource_Name links, where yyyymm represents the year (yyyy) and month (mm) of the UAS survey. Fees: None. Metadata_Reference_Information: Metadata_Date: 20210524 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Christine J. Kranenburg Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Position: Cartographer Contact_Address: Address_Type: mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: ckranenburg@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998