Lidar-derived elevation data for the Alaska Peatland Experiment (APEX) plot, Bonanza Creek Experimental Forest, Interior Alaska, collected September 20, 2025

Zechmann, J.M.Salisbury, J.B.Wikstrom Jones, K.M.2026Lidar-derived elevation data for the Alaska Peatland Experiment (APEX) plot, Bonanza Creek Experimental Forest, Interior Alaska, collected September 20, 2025dataRaw Data FileRDF 2026-17Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys13 p.https://doi.org/10.14509/32122Lidar-derived elevation data for the Alaska Peatland Experiment (APEX) plot, Bonanza Creek Experimental Forest, Interior Alaska, collected September 20, 2025, Raw Data File 2026-17, provides mobile ground-based lidar to produce a classified point cloud, a digital surface model (DSM), a digital terrain model (DTM), and an intensity model of the Alaska Peatlands Experiment (APEX) plot in the Bonanza Creek Experimental Forest in Interior Alaska during leaf-on conditions. The Bonanza Creek Long Term Ecological Research Program is part of the Long Term Ecological Research (LTER) Network, which is supported by the United States National Science Foundation and comprises 26 research sites spanning multiple biomes worldwide. This survey provides snow-free surface elevations for monitoring permafrost evolution. Lidar data and ground control data were collected on September 20, 2025, and subsequently merged and processed using a suite of geospatial processing software. These data and accompanying documentation are released as a DGGS Raw Data File and are available from the DGGS website at http://doi.org/10.14509/32122.This survey provides snow-free surface elevations for monitoring permafrost evolution. This information is essential for assessing hazards, informing risk-mitigation efforts, and supporting decision-making for communities and infrastructure.>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. Data are classified following ASPRS 2025 guidelines and contain return and intensity information. For classified ground points, the average point density is 308.1 pts/m2, and the average spacing is 5.7 cm. >dsm: The DSM represents surface elevations, including vegetation heights. The DSM is a single-band, 32-bit GeoTIFF file of 5-cm resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum). >dtm: The DTM represents bare-earth or snow-surface elevations, excluding vegetation. The DTM is a single-band, 32-bit GeoTIFF file of 5-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 that contribute 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 5-cm resolution. No Data value is set to -3.40282306074e+38.20250920ground conditioncompleteNone planned-148.324471-148.31961064.69710264.695272ISO 19115 Topic CategorygeoscientificInformationAlaska Division of Geological & Geophysical SurveysAerialAerial GeologyDigital Elevation ModelDigital Surface Model (DSM)Digital Terrain ModelElevationEngineeringEngineering GeologyEnvironmentalGeologicGeologic HazardsGeological ProcessGeologyGeomorphologyGeotechnicalHazardsLiDARLiDAR Intensity ImageLiDAR LAS File FormatPoint Cloud DataRaster ImageRemote SensingSurfaceSurficialSurficial GeologyAlaska Division of Geological & Geophysical SurveysFairbanks Mining DistrictThis 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.This survey area lies within the ancestral homelands of the Dene peoples of the lower Tanana River. This work was funded by the U.S. Geological Survey National Land Imaging Program. 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.Wolken, G.J.Hendricks, K.A.Daanen, R.P.Overbeck, J.R.Stevens, D.S.P.Masterman, S.S.2017Alaska & climate changeInformation CircularIC 64Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys2 phttps://doi.org/10.14509/29781Not applicableData quality is best nearest the traverse lines, which were limited to boardwalks. Areas far from boardwalks have relatively low point density due to line-of-sight shadows in the point cloud data.This is a full-release dataset. There was no over-collect.The offset between the point cloud (visualized as a 2 cm resolution shaded relief using only ground and bridge deck point classes) and 27 horizontal ground control points was -10.1 cm easting and +13.0 cm northing. This was changed to -0.2 cm and -5.6 cm, respectively, by applying a seven-parameter affine transformation. To determine the horizontal accuracy of the corrected point cloud, we used 14 checkpoints and measured the offset between checkpoints and their respective locations in the corrected point cloud. The project's horizontal accuracy has a root-mean-square error (RMSE) of 10.2 cm in the east-west direction and 12.9 cm in the north-south direction.We measured a mean elevation offset of +12.5 cm between 15 control points and the point cloud. This offset was reduced to 1.0 cm in nonvegetated areas and 15.1 cm in vegetated areas by applying a constant vertical correction to the lidar point data. We used 15 nonvegetated and 39 vegetated checkpoints to determine the vertical accuracy of the point cloud ground class using a Triangulated Irregular Network (TIN) approach. The project's nonvegetated vertical accuracy has a root mean square error (RMSE) of 3.8 cm, and the vegetated vertical accuracy is 17.2 cm RMSE. We evaluated the relative accuracy for this dataset as the interswath overlap consistency, yielding an RMSE of 4.6 cm.Ground survey - Ground control points were collected on September 20, 2025. We deployed a Trimble R12i GNSS base receiver and surveyed points using a rover Trimble R12i GNSS receiver/Mesa3 controller within the survey area. We collected 110 ground control points and checkpoints on boardwalk surfaces and corners, bog surfaces, tussock areas, forested areas, and tundra vegetation areas. For a GNSS base station occupation to later correct lidar survey lines, we set up a Trimble R12i in a field ~0.6 km northwest of the survey area. We processed and delivered all data in NAD83 (2011), UTM6N, and the vertical datum NAVD88 GEOID12B.20250920Lidar 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 or equal to 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 walked the existing boardwalks at the site, using a backpack-mounted system to survey from approximately 2 meters above ground level, at a ground speed of approximately 0.8 m/s, and with a scan angle set to 10 to 350 degrees. The total survey area covers approximately 0.025 km2. The survey area was accessed by car from Fairbanks. Data was collected from 1:10 pm to 2:10 pm (AKDT). The weather throughout the survey was clear with no wind.20250920Dataset processing - We processed point data in Spatial Explorer to apply initial filtering and multiple-time-around (MTA) disambiguation. MTA errors, which result from ambiguous interpretations of pulse time intervals, were corrected during this step. We processed IMU and GNSS data in Inertial Explorer and integrated traverse line information with the point cloud in Spatial Explorer. We calibrated the point data to account for sensor movement and behavior, including velocity, roll, pitch, and yaw fluctuations throughout the survey. For the lidar acquisition, the average pulse density is 116,860.5 pulses per square meter, and the average pulse spacing is 0.29 centimeters. We created a macro in Terrasolid software to classify points according to ASPRS 2025 guidelines. After classification, we applied a geometric transformation and converted ellipsoidal heights to GEOID12B (Alaska) orthometric heights. We derived raster products in ArcGIS Pro. A 5-cm DSM was interpolated from ground and vegetation classes using binning and maximum values. A 5-cm DTM was interpolated from ground-class returns using binning and minimum values. We also produced a 5-cm intensity image using average binning, with no normalization or corrections applied.2025rasterUniversal Transverse Mercator60.999600-1470500000.0000000coordinate pair.00000001.00000001MetersNAD83 (2011)GRS 806378137298.257222101NAVD88, GEOID12B0.500000metersExplicit 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.DGGSboundariesclassified_pointsClassified point cloud data are provided in LAZ format. Data are classified following ASPRS 2025 guidelines and contain return and intensity information. For classified ground points, the average point density is 308.1 pts/m2, and the average spacing is 5.7 cm.DGGSclassified_pointsdsmThe DSM represents surface elevations, including vegetation heights. The DSM is a single-band, 32-bit GeoTIFF file of 5-cm resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum).DGGSdsmdtmThe DTM represents bare-earth or snow-surface elevations, excluding vegetation. The DTM is a single-band, 32-bit GeoTIFF file of 5-cm resolution. No Data value is set to -3.40282306074e+38.DGGSdtmfootprintsFootprints for tiled data.DGGSfootprintslidar_intensityThe lidar intensity image describes the relative amplitude of reflected signals that contribute 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 5-cm resolution. No Data value is set to -3.40282306074e+38.DGGSlidar_intensityAlaska 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 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