{"action":"create","ckan_id":null,"date_created":"Sat, 14 Feb 2026 20:53:04 GMT","date_finished":null,"harvest_job_id":"b099ff79-e0c0-4989-8abd-bd643fba622f","harvest_source_id":"31f41541-38a0-400b-b240-10ebcb0acd9a","id":"6ab82454-c2e8-4d39-b281-fc220b93b648","identifier":"https://dggs.alaska.gov/webpubs/metadata/RDF2024-20.xml","parent_identifier":null,"source_hash":"d7c506c0035cf45ea06ec1336f081b82abeaee79a906ef83881f423943afb87c","source_raw":"Horen, K.C.Nieminski, N.M.Poisson, A.C.Siemsen, Z.J.2024Photogrammetry-derived orthoimagery and elevation data for Kongiganak, Alaska, collected June 7, 2023dataRaw Data FileRDF 2024-20Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys9 p.https://doi.org/10.14509/31288Photogrammetry-derived orthoimagery and elevation data for Kongiganak, Alaska, collected June 7, 2023, Raw Data File 2024-20, provides low-altitude aerial images from an unmanned aerial vehicle (UAV) in the community of Kongiganak, Alaska, on June 7, 2023. We used Structure-from-Motion (SfM) photogrammetry to produce two digital surface models (DSM) and two orthorectified images. The populated areas of Kongiganak were the focus of the primary aerial survey, while the secondary aerial survey covered the landfill to the northwest of the community. The orthoimage and elevation data are useful for assessing riverine hazards and changes over time. All files can be downloaded from the Alaska Division of Geological & Geophysical Surveys website (http://doi.org/10.14509/31288).The orthoimage and elevation data are useful for assessing riverine hazards and changes over time.>boundaries: A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data. Also includes footprints for tiled data.\t\r\n>dsm: The DSMs represent surface elevations including the height of vegetation, buildings, and other man-made features derived from the dense point clouds. The DSMs are single-band, 32-bit floating point GeoTIFF files with No Data values set to -3.4028235e+38. The DSM of the primary survey area was generated with a GSD of 0.049 m. The DSM of the secondary survey area was generated with a GSD of 0.045 m.\t\r\n>ortho_rgb: The orthoimages are three-band (red, green, blue), eight-bit unsigned GeoTIFF files with No Data values set to 0. The orthoimage of the primary survey area is derived from a color-adjusted mosaic of 1,362 aerial photographs with a GSD of 0.025 m per pixel. The orthoimage of the secondary survey area is derived from a color-adjusted mosaic of 230 aerial photographs with a GSD of 0.022 m per pixel.20230607ground conditioncompleteNone planned-162.921762-162.86505959.96786959.952600ISO 19115 Topic CategorygeoscientificInformationAlaska Division of Geological & Geophysical SurveysCoastalCoastal ErosionCoastal PlainCoastal and RiverDGGSDigital Elevation ModelDigital Surface Model (DSM)ElevationEmergency PreparednessEngineeringEngineering GeologyErosionGeologicGeologic HazardsGeological ProcessGeologyGeomorphologyGeophysicsGeotechnicalHazardsMarine GeologyRaster ImageRemote SensingStructure From MotionSurfaceSurficialSurficial GeologyTopographyAlaska Division of Geological & Geophysical SurveysKongiganakKongnignanohk RiverSouthwest AlaskaYukon-Kuskokwim DeltaThis report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below).Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product.Alaska Division of Geological & Geophysical SurveysMetadata Managermailing and physical
3354 College Road
FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysPlease view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible.We thank the Native Village of Kongiganak for supporting the creation of these data products, made possible with National Fish and Wildlife Foundation's National Coastal Resilience Funding through our partners at the Alaska Native Tribal Health Consortium. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the DGGS, the U.S. Government, or the National Fish and Wildlife Foundation and its funding sources. Mention of trade names or commercial products does not constitute their endorsement by DGGS, the U.S. Government, or the National Fish and Wildlife Foundation and its funding sources.Horen, K.C.Nieminski, N.M.Poisson, A.C.Siemsen, Z.J.2024Single-beam bathymetric data near Kongiganak, Alaska, collected June 6, 2023Raw Data FileRDF 2024-4Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys9 phttps://doi.org/10.14509/31149Overbeck, J.R.Hendricks, M.D.Kinsman, N.E.M.2018Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment L: Kipnuk to KongiganakRaw Data FileRDF 2017-8LFairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys3 phttps://doi.org/10.14509/30090Overbeck, J.R.Hendricks, M.D.Kinsman, N.E.M.2018Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment M: Kongiganak to BethelRaw Data FileRDF 2017-8MFairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys3 phttps://doi.org/10.14509/30091Not applicableDGGS visually inspected the orthoimage for data errors such as shifts, seamline mismatches, and water noise overlapping land. Visual errors common to these SfM photogrammetry products include discontinuous powerlines and distortion near high-angle features like buildings, as well as water boundaries. Highly reflective objects such as water bodies, metal roofs, and white paint may cause overexposure, leading to spurious elevation points. There were no significantly erroneous areas that required repair.This is a full-release dataset.DGGS quantified the horizontal accuracy of the GNSS position data using the latitudinal and longitudinal peak-to-peak errors provided by OPUS. Consistent with OPUS shared solution requirements (NOAA, 2022), DGGS considers high-quality GNSS solutions to have latitudinal and longitudinal errors less than or equal to 0.04 m.\r\nWe quantified the horizontal accuracy of the DSMs and orthoimages by comparing the known locations of photo-identifiable check points measured with GNSS against their modeled locations in the photogrammetric products. These are independent checkpoints not used during processing. X and Y errors are calculated as the root-mean-square (RMS) error of offsets. The primary survey area contained 12 check points, with X and Y errors of 0.043 m and 0.016 m, respectively, and a total horizontal error, the root-sum-square error of X and Y RMS errors, of 0.046 m. The secondary survey area contained 5 check points, with X and Y errors of 0.032 m and 0.013 m, respectively, and a total horizontal error of 0.035 m.DGGS quantified the vertical accuracy of the GNSS position data using the combined ellipsoidal height peak-to-peak errors provided by OPUS and orthometric height RMS error provided by NOAA's Vertical Datum Transformation software (NOAA, 2016; table 1). Consistent with OPUS shared solution requirements (NOAA, 2022), DGGS considers high-quality GNSS solutions to have vertical errors less than or equal to 0.08 m. We quantified the vertical accuracy of the DSMs using the same check points used to quantify the horizontal accuracy. The RMS error of Z offsets is 0.023 m within the primary survey area and 0.019 m within the secondary survey area. The total RMS error (X, Y, and Z) is 0.051 m within the primary survey area and 0.040 m within the secondary survey area.Ground survey - On June 7, 2023, DGGS temporarily installed a Trimble R10 receiver sampling at 5 Hz as a Global Navigation Satellite System (GNSS) base station over a temporary benchmark. This provided real-time kinematic (RTK) corrections to the ground rover, a Trimble R8s GNSS receiver. Using the ground rover, DGGS measured the location of 24 photo-identifiable ground control points (GCPs) within the primary survey area and 10 within the secondary survey area.20230607Aerial survey - DGGS conducted flights on June 7, 2023, from approximately 4:15 PM to 8:30 PM AKDT using a DJI Phantom 4 RTK UAV with a FC6310R camera model (8.8 mm lens) to collect 1,813 20-megapixel JPEG photographs (5,472 x 3,648 pixels per image). The operator returned the UAV seven times to change batteries. DGGS flew the primary and secondary aerial surveys 120 m and 110 m above ground-level (AGL), respectively. Both surveys were flown with 75 percent side- and frontlap at 9.5 m/s, with nadir orientation stabilized using a three-axis gimbal. This resulted in images covering the primary survey area of 2.280 km2 with a ground sampling distance (GSD) of 0.025 m and the secondary survey area of 0.395 km2 with a ground sampling distance (GSD) of 0.022 m. The weather throughout the survey was mostly cloudy with light wind. No abnormalities were observed during the flights.20230607Dataset processing - Base positions were corrected using Online Positioning User Service (OPUS) solutions, which were used to update the UAV and ground rover positions with post-processed kinematic (PPK) adjustments. UAV positions were updated in RTKLIB (Version 2.4.3) software with the following settings applied: L1+L2 frequencies forward and backward filtered; a 10-degree elevation mask; receiver dynamics disabled; broadcast ionosphere and Saastamoinen troposphere corrections; a minimum fixed-ambiguity ratio of three; and L1/L2 code/carrier-phase error ratios of 100/100. During post-processing, DGGS applied International GNSS Service (IGS) precise orbits and final clock solutions retrieved from the Crustal Dynamics Data Information System (CDDIS) found at urs.earthdata.nasa.gov. Final corrected data were exported as time-stamped position files in WGS84 horizontal coordinate system with ellipsoidal heights and paired to corresponding photographs using an Aerotas P4RTK PPK Adjustments (Version 1) macro-enabled Microsoft Excel file. Ground rover positions were updated using PPK corrections in Trimble Business Center (Version 5.51) software using default settings. Final corrected data were exported as comma-delimited text files in WGS84 horizontal coordinate system with ellipsoidal heights. DGGS used Agisoft Metashape Professional (Version 1.8.3 build 14331) software for photogrammetric processing following the steps and settings outlined in Over and others (2021). During processing of the primary survey area, DGGS used 12 GCPs for photograph alignment and lens distortion parameter optimization, leaving 12 GCPs as horizontal and vertical check points. During processing of the secondary survey area, DGGS used 5 GCPs for photograph alignment and lens distortion parameter optimization, leaving 5 GCPs as horizontal and vertical check points. A confidence filter was applied to the resulting dense point cloud, eliminating all points derived from fewer than three discrete camera positions. Additional noise was removed from the dense point clouds through visual inspection.2023rasterUniversal Transverse Mercator30.999600-1650500000.0000000coordinate pair.00000001.00000001MetersNAD83 (2011)GRS 806378137298.257222101NAVD88, GEOID12B0.001metersExplicit elevation coordinate included with horizontal coordinatesboundariesA boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data. Also includes footprints for tiled data.DGGSboundariesdsmThe DSMs represent surface elevations including the height of vegetation, buildings, and other man-made features derived from the dense point clouds. The DSMs are single-band, 32-bit floating point GeoTIFF files with No Data values set to -3.4028235e+38. The DSM of the primary survey area was generated with a GSD of 0.049 m. The DSM of the secondary survey area was generated with a GSD of 0.045 m.DGGSdsmortho_rgbThe orthoimages are three-band (red, green, blue), eight-bit unsigned GeoTIFF files with No Data values set to 0. The orthoimage of the primary survey area is derived from a color-adjusted mosaic of 1,362 aerial photographs with a GSD of 0.025 m per pixel. The orthoimage of the secondary survey area is derived from a color-adjusted mosaic of 230 aerial photographs with a GSD of 0.022 m per pixel.DGGSortho_rgbAlaska Division of Geological & Geophysical SurveysMetadata Managermailing and physical
3354 College Road
FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysPlease view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible.RDF 2024-20The State of Alaska makes no expressed or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product.DGGS publications are available as free online downloads or you may purchase paper hard-copies or digital files on CD/DVD or other digital storage media by mail, phone, fax, or email from the DGGS Fairbanks office. To purchase this or other printed reports and maps, contact DGGS by phone (907-451-5020), e-mail (dggspubs@alaska.gov), or fax (907-451-5050). Payment accepted: Cash, check, money order, VISA, or MasterCard. Turnaround time is 1-2 weeks unless special arrangements are made and an express fee is paid. Shipping charge will be the actual cost of postage and will be added to the total amount due. Contact us for the exact shipping amount.Contact DGGS for current pricingdata20240802boundaries, dsm and ortho rgbhttps://doi.org/10.14509/31288Free download20240806Alaska Division of Geological & Geophysical SurveysSimone MontayneMetadata Managermailing and physical
3354 College Road
FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysFGDC Content Standard for Digital Geospatial MetadataFGDC-STD-001-1998If the user has modified the data in any way they are obligated to describe the types of modifications they have performed in the supporting metadata file. User specifically agrees not to imply that changes they made were approved by the Alaska Department of Natural Resources or Division of Geological & Geophysical Surveys.https://dggs.alaska.gov/metadata/dggs.extdggs metadata extensions","source_transform":null,"status":"error"}