Identification_Information: Citation: Citation_Information: Originator: Zechmann, J.M. Originator: Liljedahl, A.K. Originator: Wolken, G.J. Originator: Jorgenson, M.T. Originator: Witharana, Chandi Publication_Date: 2025 Title: Lidar-derived elevation data for Jago River permafrost research site, collected August 1, 2025 Geospatial_Data_Presentation_Form: data Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2025-30 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 15 p Online_Linkage: https://doi.org/10.14509/31748 Description: Abstract: Lidar-derived elevation data for Jago River permafrost research site, collected August 1, 2025, Raw Data File 2025-30, provides classified point cloud data, a digital surface model (DSM), a digital terrain model (DTM), and an intensity model derived from aerial lidar surveys. The data cover a permafrost study area adjacent to the Jago River in Northern Alaska. The Alaska Division of Geological & Geophysical Surveys (DGGS) conducted the work during snow‑free conditions. The data were acquired to support research on permafrost evolution and to provide baseline elevation information for monitoring environmental change. Aerial lidar data were collected on August 1, 2025, and ground control data were obtained between August 1-3, 2025. These data are provided as a Raw Data File under an open end-user license and are available on the DGGS website (http://doi.org/10.14509/31748). Purpose: The products were generated to support permafrost evolution research and to provide baseline elevation data for monitoring environmental change, including terrain morphology, thaw subsidence, and other indicators of permafrost degradation in Northern Alaska. Supplemental_Information: >boundaries: A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data. >classified_points: Classified point cloud data are provided in LAZ format. Classification follows ASPRS 2025 standards with return and intensity values. Ground-classified points have a mean density of 41.1 pts/m2 and an average spacing of 15.6 cm. >dsm: The DSM represents surface elevations, including heights of vegetation and structures. The DSM is a single-band, 32-bit tiled GeoTIFF dataset of 10-cm resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum). >dtm: The DTM represents bare earth elevations, excluding vegetation and structures. The DTM is a single-band, 32-bit tiled GeoTIFF dataset of 10-cm resolution. No Data value is set to -3.40282306074e+38. >footprints: Footprints for tiled data. >lidar_intensity: The lidar intensity image describes the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is (1) primarily a function of scanned object reflectance in relation to the signal frequency, (2) dependent on ambient conditions, and (3) not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit GeoTIFF file of 1-m resolution, with a No Data value set to -3.40282306074e+38. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 20250801 Currentness_Reference: ground condition Status: Progress: complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -143.779168 East_Bounding_Coordinate: -143.553728 North_Bounding_Coordinate: 69.767903 South_Bounding_Coordinate: 69.717603 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: Aerial Theme_Keyword: Aerial Geology Theme_Keyword: Climate Change Theme_Keyword: Coastal Plain Theme_Keyword: DGGS Theme_Keyword: Digital Elevation Model Theme_Keyword: Digital Surface Model (DSM) Theme_Keyword: Digital Terrain Model Theme_Keyword: Elevation Theme_Keyword: Engineering Theme_Keyword: Engineering Geology Theme_Keyword: Environmental Theme_Keyword: Geologic Theme_Keyword: Geologic Hazards Theme_Keyword: Geological Process Theme_Keyword: Geology Theme_Keyword: Geomorphology Theme_Keyword: Geotechnical Theme_Keyword: LiDAR Theme_Keyword: LiDAR Intensity Image Theme_Keyword: LiDAR LAS File Format Theme_Keyword: Periglacial Slope Failure Theme_Keyword: Permafrost Theme_Keyword: Permafrost and Periglacial Theme_Keyword: Point Cloud Data Theme_Keyword: Raster Image Theme_Keyword: Remote Sensing Theme_Keyword: Surface Theme_Keyword: Surficial Theme_Keyword: Surficial Geology Theme_Keyword: Topography Theme_Keyword: Unconsolidated Deposits Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Canning Mining District Place_Keyword: Jago River Place_Keyword: North Slope Place_Keyword: Okpirourak Creek Access_Constraints: This 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). Use_Constraints: 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. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: GIS Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Rd City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: 907-451-5020 Contact_Electronic_Mail_Address: dggsgis@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Data_Set_Credit: A subaward from the National Science Foundation, grant number 2234117, funded this work. We thank Alpine Air Alaska for their aviation expertise and for their contributions to these data products, and Toolik Field Station and Battelle ARO for providing logistical support. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government. Cross_Reference: Citation_Information: Originator: Wolken, G.J. Originator: Hendricks, K.A. Originator: Daanen, R.P. Originator: Overbeck, J.R. Originator: Stevens, D.S.P. Originator: Masterman, S.S. Publication_Date: 2017 Title: Alaska & climate change Series_Information: Series_Name: Information Circular Issue_Identification: IC 64 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 2 p Online_Linkage: https://doi.org/10.14509/29781 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Not applicable Logical_Consistency_Report: Data quality is consistent throughout the survey, save for gaps over bodies of water. Data were validated using commercial GIS software. Completeness_Report: This is a full-release dataset. There was no over-collect. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The offset between the pointcloud (visualized as a DSM hillshade or intensity image) and 20 ground control points was 2.2 cm measured west to east and 3.7 cm measured south to north. This was changed to -4.4 cm and +0.7 cm, respectively, by applying a constant horizontal correction. We used 17 checkpoints to determine the horizontal accuracy of the corrected point cloud by measuring the offset between checkpoints and their respective locations in the dsm and/or intensity image produced from the corrected point cloud. The project's horizontal accuracy has a root-mean-square error (RMSE) of 10.5 cm in the east-west direction and 8.3 cm in the north-south direction. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: We measured a mean elevation offset of -1.5 cm between 37 control points and the point cloud . This offset was changed to +1.8 cm in non-vegetated areas and +13.1 cm in vegetated areas by applying a constant vertical correction of +1.5 cm to the lidar point data. We used 37 non-vegetated and 67 vegetated checkpoints to determine the vertical accuracy of the point cloud ground class using a Triangulated Irregular Network (TIN) approach. The project's vertical accuracy has an RMSE of 8.7 cm in non-vegetated areas and 18.6 cm in vegetated areas. We evaluated the relative accuracy of this dataset using interswath overlap consistency and found a 5.7 cm RMSE. Lineage: Process_Step: Process_Description: Ground survey - On August 1, 2025, we established a GNSS base station at the field camp using a Trimble R12i to support subsequent correction of lidar survey flightlines. This location also served as the base station for ground control point collection. Ground control points were collected on August 1-3, 2025. We deployed a Trimble R12i GNSS base receiver and surveyed points with a rover Trimble R12i GNSS receiver/Mesa3 controller within the survey area. We collected 157 ground control points and checkpoints; ground control points were collected on bare earth (gravel), and checkpoints were taken in areas of bare earth, tundra vegetation, reeds, shrubs, and tussocks. Where possible, we surveyed existing markers (rock piles, tents, and barrels) to determine horizontal accuracy later. Process_Date: 20250803 Process_Step: Process_Description: Aerial survey - DGGS used a Riegl VUX1-LR22 laser scanner with a global navigation satellite system (GNSS) and a Northrop Grumman LN-200C inertial measurement unit (IMU) integrated by Phoenix LiDAR Systems. The sensor can collect up to 1,500,000 points per second at a range of 230 m, or a minimum of 50,000 points per second at 1,000 m (ranges assume greater than 20 percent natural reflectance). The scanner operated with a pulse refresh rate of 1,500,000 pulses per second at a scan rate of 200 revolutions per second. We used a Robinson R44 helicopter to survey from an elevation of approximately 100-150 m above ground level, at a ground speed of approximately 30 m/s, and with a scan angle set from 120 to 240 degrees. The total survey area covers approximately 26.3 km2. The survey area was accessed by air from Toolik Field Station. Data were collected from 1:05 pm to 3:55 pm (AKST). The weather throughout the survey was clear with no wind. Process_Date: 20250801 Process_Step: Process_Description: Dataset processing - We processed point data in Spatial Explorer for initial filtering and multiple-time-around (MTA) disambiguation. MTA errors, corrected in this process, result from ambiguous interpretations of received pulse time intervals and occur more frequently with higher pulse refresh rates. IMU and GNSS data were processed in Inertial Explorer, and flightline information was integrated with the point cloud in Spatial Explorer. We calibrated the point data at an incrementally precise scale of sensor movement and behavior, incorporating sensor velocity, roll, pitch, and yaw fluctuations throughout the survey. For the lidar data collection, the average pulse density is 150.3 pulses/m2, and the average pulse spacing is 8.2 cm. We created a macro (an ordered list of point classification commands tailored to this dataset) in Terrasolid software and classified points in accordance with the American Society for Photogrammetry & Remote Sensing (ASPRS) 2025 guidelines (ASPRS, 2025). Once classified, we applied a geometric transformation and converted the points from ellipsoidal heights to GEOID12B (Alaska) orthometric heights. Raster products were derived from the point cloud in ArcGIS Pro. A 10-cm DSM was interpolated from ground and vegetation classes using a binning method and maximum values. A 10-cm DTM was interpolated from all ground-class returns using a binning method and minimum values. We also produced a 10-cm intensity image using average binning in ArcGIS Pro, with no normalization or corrections applied. Process_Date: 2025 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: raster Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 7 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -141 Latitude_of_Projection_Origin: 0 False_Easting: 500000.000000 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: .00000001 Ordinate_Resolution: .00000001 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: NAD83 (2011) Ellipsoid_Name: GRS 80 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257222101 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: NAVD88, GEOID12B Altitude_Resolution: 0.500000 Altitude_Distance_Units: meters Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: boundaries Entity_Type_Definition: A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: boundaries Detailed_Description: Entity_Type: Entity_Type_Label: classified_points Entity_Type_Definition: Classified point cloud data are provided in LAZ format. Classification follows ASPRS 2025 standards with return and intensity values. Ground-classified points have a mean density of 41.1 pts/m2 and an average spacing of 15.6 cm. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: classified_points Detailed_Description: Entity_Type: Entity_Type_Label: dsm Entity_Type_Definition: The DSM represents surface elevations, including heights of vegetation and structures. The DSM is a single-band, 32-bit tiled GeoTIFF dataset of 10-cm resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum). Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: dsm Detailed_Description: Entity_Type: Entity_Type_Label: dtm Entity_Type_Definition: The DTM represents bare earth elevations, excluding vegetation and structures. The DTM is a single-band, 32-bit tiled GeoTIFF dataset of 10-cm resolution. No Data value is set to -3.40282306074e+38. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: dtm Detailed_Description: Entity_Type: Entity_Type_Label: footprints Entity_Type_Definition: Footprints for tiled data. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: footprints Detailed_Description: Entity_Type: Entity_Type_Label: lidar_intensity Entity_Type_Definition: The lidar intensity image describes the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is (1) primarily a function of scanned object reflectance in relation to the signal frequency, (2) dependent on ambient conditions, and (3) not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit GeoTIFF file of 1-m resolution, with a No Data value set to -3.40282306074e+38. Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: lidar_intensity Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys Contact_Person: Simone Montayne Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: 907-451-5020 Contact_Facsimile_Telephone: 907-451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Contact_Instructions: Please view our website (http://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. Resource_Description: RDF 2025-30 Distribution_Liability: The State of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services 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, any failure thereof, or otherwise, and 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. Standard_Order_Process: Non-digital_Form: DGGS publications are available as free online downloads. 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. Fees: see http://dx.doi.org/10.14509/31748 Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: data Format_Version_Date: 20251210 Format_Information_Content: boundaries, classified points, dsm, dtm and footprints Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://dx.doi.org/10.14509/31748 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20251210 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Simone Montayne Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: 907-451-5020 Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Use_Constraints: If the user has modified this metadata file in any way, the user is obligated to describe the types of modifications the user has made. User specifically agrees not to misrepresent this metadata file, 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. Metadata_Extensions: Online_Linkage: http://www.dggs.alaska.gov/metadata/dggs.ext Profile_Name: dggs metadata extensions