{"action":"create","ckan_id":null,"date_created":"Sat, 07 Feb 2026 20:35:13 GMT","date_finished":null,"harvest_job_id":"5e5e88d9-683a-467f-8bee-1d6cfcb471c0","harvest_source_id":"31f41541-38a0-400b-b240-10ebcb0acd9a","id":"cf8d04f4-b1fc-4fdc-ac3e-f56a3f8c79f0","identifier":"https://dggs.alaska.gov/webpubs/metadata/RDF2023-17.xml","parent_identifier":null,"source_hash":"86b7f74afc77acf6c4fd8e093e01b1feb42cc1f68961d8b6ff9a5b8493164856","source_raw":"<?xml version=\"1.0\" encoding=\"UTF-8\"?><metadata><idinfo><citation><citeinfo><origin>Zechmann, J.M.</origin><origin>Herbst, A.M.</origin><origin>Buzard, R.M.</origin><pubdate>2023</pubdate><title>Lidar-derived elevation data for Tuntutuliak, Southwest Alaska, collected August 18, 2021</title><geoform>data</geoform><serinfo><sername>Raw Data File</sername><issue>RDF 2023-17</issue></serinfo><pubinfo><pubplace>Fairbanks, Alaska, United States</pubplace><publish>Alaska Division of Geological &amp; Geophysical Surveys</publish></pubinfo><othercit>7 p.</othercit><onlink>https://doi.org/10.14509/31033</onlink></citeinfo></citation><descript><abstract>Lidar-derived elevation data for Tuntutuliak, Southwest Alaska, collected August 18, 2021, Raw Data File 2023-17, provides aerial lidar derived classified point cloud data, a digital surface model (DSM), a digital terrain model (DTM), and an intensity model of Tuntutuliak, Southwest Alaska. Data were collected during leaf-on ground conditions. The survey provides snow-free surface elevation data for assessing coastal erosion and flooding hazards. Ground control data and aerial lidar data were collected on August 18, 2021, and subsequently processed using a suite of geospatial processing software. All files can be downloaded from the Alaska Division of Geological &amp; Geophysical Surveys website (http://doi.org/10.14509/31033).</abstract><purpose>The survey provides snow-free surface elevation data for assessing coastal erosion and flooding hazards.</purpose><supplinf>&gt;boundaries:    A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data.\t\r\n&gt;classified_points:    Classified point cloud data are provided in compressed LAZ format. Data are classified following ASPRS 2019 guidelines and contain return and intensity information. The average pulse spacing is 55.9 cm, and the average density is 3.21 pts/m2. \t\r\n&gt;dsm:    The DSM represents surface elevations, including heights of vegetation, buildings, boardwalks, powerlines, etc. The DSM is a single-band, 32-bit GeoTIFF file of 50-centimeter resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum).\t\r\n&gt;dtm:    The DTM represents bare earth elevations, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file of 50-centimeter resolution. No Data value is set to -3.40282306074e+38.\t\r\n&gt;lidar_intensity:    The lidar intensity image depicts the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is primarily a function of scanned object reflectance in relation to the signal frequency, is dependent on ambient conditions, and is not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit float GeoTIFF file of 1-meter resolution. No Data value is set to -3.40282306074e+38.</supplinf></descript><timeperd><timeinfo><sngdate><caldate>20210818</caldate></sngdate></timeinfo><current>ground condition</current></timeperd><status><progress>complete</progress><update>None planned</update></status><spdom><bounding><westbc>-162.718058</westbc><eastbc>-162.612191</eastbc><northbc>60.374823</northbc><southbc>60.320544</southbc></bounding></spdom><keywords><theme><themekt>ISO 19115 Topic Category</themekt><themekey>geoscientificInformation</themekey></theme><theme><themekt>Alaska Division of Geological &amp; Geophysical Surveys</themekt><themekey>DGGS</themekey><themekey>Digital Elevation Model</themekey><themekey>Digital Surface Model (DSM)</themekey><themekey>Digital Terrain Model</themekey><themekey>Elevation</themekey><themekey>Emergency Preparedness</themekey><themekey>Engineering</themekey><themekey>Engineering Geology</themekey><themekey>Geologic</themekey><themekey>Geologic Hazards</themekey><themekey>Geological Process</themekey><themekey>Geology</themekey><themekey>Geomorphology</themekey><themekey>Geotechnical</themekey><themekey>Hazards</themekey><themekey>LiDAR</themekey><themekey>LiDAR Intensity Image</themekey><themekey>LiDAR LAS File Format</themekey><themekey>Point Cloud Data</themekey><themekey>Raster Image</themekey><themekey>Remote Sensing</themekey><themekey>Surface</themekey><themekey>Surficial</themekey><themekey>Surficial Geology</themekey><themekey>Topography</themekey></theme><place><placekt>Alaska Division of Geological &amp; Geophysical Surveys</placekt><placekey>Kinak River</placekey><placekey>Southwest Alaska</placekey><placekey>Tuntutuliak</placekey></place></keywords><accconst>This report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological &amp; Geophysical Surveys (see contact information below).</accconst><useconst>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 &amp; 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.</useconst><ptcontac><cntinfo><cntorgp><cntorg>Alaska Division of Geological &amp; Geophysical Surveys</cntorg></cntorgp><cntpos>Metadata Manager</cntpos><cntaddr><addrtype>mailing and physical</addrtype><address>3354 College Road</address><city>Fairbanks</city><state>AK</state><postal>99709-3707</postal><country>USA</country></cntaddr><cntvoice>(907)451-5020</cntvoice><cntfax>(907)451-5050</cntfax><cntemail>dggspubs@alaska.gov</cntemail><hours>8 am to 4:30 pm, Monday through Friday, except State holidays</hours><cntinst>Please 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.</cntinst></cntinfo></ptcontac><datacred>This survey area is on the traditional homelands of the Yup'ik people. Data collection and processing were funded by the National Fish and Wildlife Foundation (now known as the National Coastal Resilience Fund), grant number 0318.20.069342, through the Alaska Native Tribal Health Consortium. We thank Clearwater Air for their aviation expertise and contribution to these data products. 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.</datacred><crossref><citeinfo><origin>Buzard, R.M.</origin><origin>Turner, M.M.</origin><origin>Miller, K.Y.</origin><origin>Antrobus, D.C.</origin><origin>Overbeck, J.R.</origin><pubdate>2021</pubdate><title>Erosion exposure assessment of infrastructure in Alaska coastal communities</title><serinfo><sername>Report of Investigation</sername><issue>RI 2021-3</issue></serinfo><pubinfo><pubplace>Fairbanks, Alaska, United States</pubplace><publish>Alaska Division of Geological &amp; Geophysical Surveys</publish></pubinfo><othercit>29 p</othercit><onlink>https://doi.org/10.14509/30672</onlink></citeinfo></crossref><crossref><citeinfo><origin>Horen, K.C.</origin><origin>Buzard, R.M.</origin><origin>Overbeck, J.R.</origin><origin>Poisson, A.C.</origin><origin>Siemsen, Z.J.</origin><pubdate>2023</pubdate><title>Single-beam bathymetric data near Kwigillingok, Alaska, collected June 18-19, 2022</title><serinfo><sername>Raw Data File</sername><issue>RDF 2023-7</issue></serinfo><pubinfo><pubplace>Fairbanks, Alaska, United States</pubplace><publish>Alaska Division of Geological &amp; Geophysical Surveys</publish></pubinfo><othercit>9 p</othercit><onlink>https://doi.org/10.14509/31005</onlink></citeinfo></crossref></idinfo><dataqual><attracc><attraccr>Not applicable</attraccr></attracc><logic>This is a full-release dataset. There was no over-collect except for aircraft turns that were eliminated from the dataset. The data quality is consistent throughout the survey.</logic><complete>This data relaease is complete.</complete><posacc><horizpa><horizpar>We did not measure horizontal accuracy for this collection.</horizpar></horizpa><vertacc><vertaccr>We measured a mean offset of 48.8 cm between 33 control points and the point cloud. We reduced this offset to 0.1 cm by performing a vertical transformation of the lidar point data. We used ten checkpoints to determine the non-vegetated vertical accuracy (NVA) of the point cloud ground class using a Triangulated Irregular Network (TIN) approach. We calculated the project NVA to have a root mean square error (RMSE) of 3.7 cm. We evaluated the relative accuracy for this dataset as the interswath overlap consistency and measured it at 6.7 cm RMSE.</vertaccr></vertacc></posacc><lineage><procstep><procdesc>Ground survey - We deployed a Trimble R10 GNSS receiver at Tuntutuliak Airport. It provided a base station occupation and real-time kinematic (RTK) corrections to points we surveyed with a rover Trimble R8 GNSS receiver (internal antenna). We collected 43 ground control and checkpoints to use for calibration and to assess the vertical accuracy of the point cloud. Points were collected on bare earth, boardwalks, and vegetation (tall grass or alder). We processed and delivered all data in NAD83 (2011) UTM3N and vertical datum NAVD88 GEOID12B.</procdesc><procdate>20210818</procdate></procstep><procstep><procdesc>Aerial survey - DGGS used a Riegl VUX1-LR laser scanner integrated with a global navigation satellite system (GNSS) and Northrop Grumman LN-200C inertial measurement unit (IMU). The lidar integration system was designed by Phoenix LiDAR Systems. The sensor can collect up to 820,000 points per second at a range of up to 150 m. The scanner operated with a pulse refresh rate of 400,000 pulses per second at a scan rate of 200 lines per second. We used a Cessna 180 fixed-wing platform to survey from an elevation of ~200 m above ground level, at a ground speed of ~40 m/s, and with a scan angle set from 80 to 280 degrees. The total survey area covers ~19 km2. We flew the aerial survey on August 18, 2021, taking off from Bethel Airport and landing at Tuntutuliak Airport. Data was collected from 12:10 pm to 1:10 pm AKST. The weather throughout the survey was clear, with no wind.</procdesc><procdate>20210818</procdate></procstep><procstep><procdesc>Lidar dataset processing - We processed point data in SDCimport software 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. We processed IMU and GNSS data in Inertial Explorer, and we used Spatial Explorer software to integrate flightline information with the point cloud. 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. We created macros in Terrasolid software and classified points in accordance with American Society for Photogrammetry and Remote Sensing (ASPRS) 2019 guidelines. Once classified, we applied a geometric transformation and converted the points from ellipsoidal heights to GEOID12B (Alaska) orthometric heights. We used ArcGIS Pro to derive raster products from the point cloud. The DSM was interpolated from maximum return values from the ground, vegetation, bridge deck, and building classes using a binning method. The DTM was interpolated from all ground class returns, also using a binning method and minimum values. In ArcGIS Pro, we produced an intensity image by binning and averaging ground, vegetation, building, and bridge deck classes.</procdesc><procdate>2022</procdate></procstep></lineage></dataqual><spdoinfo><direct>raster</direct></spdoinfo><spref><horizsys><planar><gridsys><gridsysn>Universal Transverse Mercator</gridsysn><utm><utmzone>3</utmzone><transmer><sfctrmer>0.999600</sfctrmer><longcm>-165</longcm><latprjo>0</latprjo><feast>500000.000000</feast><fnorth>0</fnorth></transmer></utm></gridsys><planci><plance>coordinate pair</plance><coordrep><absres>.00000001</absres><ordres>.00000001</ordres></coordrep><plandu>Meters</plandu></planci></planar><geodetic><horizdn>NAD83 (2011)</horizdn><ellips>GRS 80</ellips><semiaxis>6378137</semiaxis><denflat>298.257222101</denflat></geodetic></horizsys><vertdef><altsys><altdatum>NAVD88, GEOID12B</altdatum><altres>0.001</altres><altunits>meters</altunits><altenc>Explicit elevation coordinate included with horizontal coordinates</altenc></altsys></vertdef></spref><eainfo><detailed><enttyp><enttypl>boundaries</enttypl><enttypd>A boundary, also known as an Area of Interest (AOI) or border, that defines the area covered by the data.</enttypd><enttypds>DGGS</enttypds><ealname>boundaries</ealname></enttyp></detailed><detailed><enttyp><enttypl>classified_points</enttypl><enttypd>Classified point cloud data are provided in compressed LAZ format. Data are classified following ASPRS 2019 guidelines and contain return and intensity information. The average pulse spacing is 55.9 cm, and the average density is 3.21 pts/m2.</enttypd><enttypds>DGGS</enttypds><ealname>classified_points</ealname></enttyp></detailed><detailed><enttyp><enttypl>dsm</enttypl><enttypd>The DSM represents surface elevations, including heights of vegetation, buildings, boardwalks, powerlines, etc. The DSM is a single-band, 32-bit GeoTIFF file of 50-centimeter resolution. No Data value is set to -3.40282306074e+38 (32-bit, floating-point minimum).</enttypd><enttypds>DGGS</enttypds><ealname>dsm</ealname></enttyp></detailed><detailed><enttyp><enttypl>dtm</enttypl><enttypd>The DTM represents bare earth elevations, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file of 50-centimeter resolution. No Data value is set to -3.40282306074e+38.</enttypd><enttypds>DGGS</enttypds><ealname>dtm</ealname></enttyp></detailed><detailed><enttyp><enttypl>lidar_intensity</enttypl><enttypd>The lidar intensity image depicts the relative amplitude of reflected signals contributing to the point cloud. Lidar intensity is primarily a function of scanned object reflectance in relation to the signal frequency, is dependent on ambient conditions, and is not necessarily consistent between separate scans. The intensity image is a single-band, 32-bit float GeoTIFF file of 1-meter resolution. No Data value is set to -3.40282306074e+38.</enttypd><enttypds>DGGS</enttypds><ealname>lidar_intensity</ealname></enttyp></detailed></eainfo><distinfo><distrib><cntinfo><cntorgp><cntorg>Alaska Division of Geological &amp; Geophysical Surveys</cntorg></cntorgp><cntpos>Metadata Manager</cntpos><cntaddr><addrtype>mailing and physical</addrtype><address>3354 College Road</address><city>Fairbanks</city><state>AK</state><postal>99709-3707</postal><country>USA</country></cntaddr><cntvoice>(907)451-5020</cntvoice><cntfax>(907)451-5050</cntfax><cntemail>dggspubs@alaska.gov</cntemail><hours>8 am to 4:30 pm, Monday through Friday, except State holidays</hours><cntinst>Please 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.</cntinst></cntinfo></distrib><resdesc>RDF 2023-17</resdesc><distliab>The 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.</distliab><stdorder><nondig>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.</nondig><fees>Contact DGGS for current pricing</fees></stdorder><stdorder><digform><digtinfo><formname>data</formname><formverd>20231215</formverd><formcont>boundaries, classified points, dsm, dtm and lidar intensity</formcont></digtinfo><digtopt><onlinopt><computer><networka><networkr>https://doi.org/10.14509/31033</networkr></networka></computer></onlinopt></digtopt></digform><fees>Free download</fees></stdorder></distinfo><metainfo><metd>20231215</metd><metc><cntinfo><cntorgp><cntorg>Alaska Division of Geological &amp; Geophysical Surveys</cntorg><cntper>Simone Montayne</cntper></cntorgp><cntpos>Metadata Manager</cntpos><cntaddr><addrtype>mailing and physical</addrtype><address>3354 College Road</address><city>Fairbanks</city><state>AK</state><postal>99709-3707</postal><country>USA</country></cntaddr><cntvoice>(907)451-5020</cntvoice><cntfax>(907)451-5050</cntfax><cntemail>dggspubs@alaska.gov</cntemail><hours>8 am to 4:30 pm, Monday through Friday, except State holidays</hours></cntinfo></metc><metstdn>FGDC Content Standard for Digital Geospatial Metadata</metstdn><metstdv>FGDC-STD-001-1998</metstdv><metuc>If 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 &amp; Geophysical Surveys.</metuc><metextns><onlink>https://dggs.alaska.gov/metadata/dggs.ext</onlink><metprof>dggs metadata extensions</metprof></metextns></metainfo></metadata>","source_transform":null,"status":"error"}
