gov.noaa.nmfs.inport:68018 eng UTF8 dataset Elevation OCM Partners resourceProvider NOAA Office for Coastal Management (843) 740-1202 2234 South Hobson Ave Charleston SC 29405-2413 coastal.info@noaa.gov https://coast.noaa.gov WWW:LINK-1.0-http--link NOAA Office for Coastal Management Website NOAA Office for Coastal Management Home Page information pointOfContact 2026-04-30T00:00:00 ISO 19115-2 Geographic Information - Metadata Part 2 Extensions for imagery and gridded data ISO 19115-2:2009(E) NAD83(2011) / UTM zone 3N2008-11-12publicationEuropean Petroleum Survey Grouphttps://apps.epsg.org/api/v1/CoordRefSystem/6332/export/?format=gmlurn:ogc:def:crs:EPSG:63326.18.3 2019 AK DGGS Lidar: Kotlik, Alaska 2019 creation 2020 publication NOAA/NMFS/EDM 68018 https://www.fisheries.noaa.gov/inport/item/68018 WWW:LINK-1.0-http--link Full Metadata Record View the complete metadata record on InPort for more information about this dataset. information https://coast.noaa.gov/ WWW:LINK-1.0-http--link NOAA's Office for Coastal Management (OCM) website Information on the NOAA Office for Coastal Management (OCM) download https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9607/details/9607 WWW:LINK-1.0-http--link Custom Point Download Link to custom download, from the Data Access Viewer (DAV), the raster Digital Elevation Model (DEM) data that were created from this lidar data set. download https://coast.noaa.gov/dataviewer/ WWW:LINK-1.0-http--link NOAA's Office for Coastal Management (OCM) Data Access Viewer (DAV) The Data Access Viewer (DAV) allows a user to search for and download elevation, imagery, and land cover data for the coastal U.S. and its territories. The data, hosted by the NOAA Office for Coastal Management, can be customized and requested for free download through a checkout interface. An email provides a link to the customized data, while the original data set is available through a link within the viewer. download https://dggs.alaska.gov/webpubs/dggs/rdf/text/rdf2020_015.pdf WWW:LINK-1.0-http--link Lidar Report This lidar report provides accompanying information about the collection and processing of this lidar data set. download The Alaska Division of Geological & Geophysical Surveys (DGGS) used aerial lidar to produce a digital terrain model (DTM), surface model (DSM), and intensity model for the area surrounding the community of Kotlik, Alaska. Detailed bare earth elevation data for the Kotlik area support and inform potential infrastructure development and provide critical information required to assess geomorphic activity. Airborne data were collected on August 17, 2019, and subsequently processed in Terrasolid and ArcGIS. Ground control was collected between August 20-22, 2019, by the Alaska Division of Mining, Land, and Water. This data collection is released as a Raw Data File with an open end-user license. All files can be downloaded free of charge from the Alaska Division of Geological & Geophysical Surveys website (http://doi.org/10.14509/30561). The NOAA Office for Coastal Management (OCM) downloaded this data set from this AK DGGS site: https://elevation.alaska.gov/ These files were processed to the NOAA Digital Coast Data Access Viewer (DAV) and AWS S3. The total number of files downloaded and processed was 215. During processing, it was noted that there are lidar points that fall in water areas and on structures that are classified as ground. In addition to the lidar point data, the bare earth Digital Elevation Model (DEM) data at a 0.5 meter grid spacing, created from the lidar point data are also available from the NOAA Digital Coast. Links to these data are provided in the URL section of this metadata record. This data set contains point cloud data(' in LAZ (compressed LAS) format', ''). The data may have been reprojected or otherwise modified from the original data in an automated process. Disregard projection information in this abstract and refer to the spatial reference section. Detailed bare earth elevation data for the Kotlik area support and inform potential infrastructure development and provide critical information required to assess geomorphic activity. This data release is one of a series of DGGS publications to present elevation data. These data were paid for by the State of Alaska and collected and processed by DGGS. A ground survey was conducted for quality control by the Alaska Division of Mining, Land, and Water, and supported by the Native Village of Bill Moore's Slough and the Native Village of Kotlik., Herbst, A.M. Daanen, R.D. The custom download may be cited as National Oceanic and Atmospheric Administration (NOAA) Digital Coast Data Access Viewer. Charleston, SC: NOAA Office for Coastal Management. Accessed 2026-06-21 at https://coast.noaa.gov/dataviewer. completed NOAA Office for Coastal Management (843) 740-1202 2234 South Hobson Ave Charleston SC 29405-2413 coastal.info@noaa.gov https://coast.noaa.gov WWW:LINK-1.0-http--link NOAA Office for Coastal Management Website NOAA Office for Coastal Management Home Page information pointOfContact NOAA Office for Coastal Management (843) 740-1202 2234 South Hobson Ave Charleston SC 29405-2413 coastal.info@noaa.gov https://coast.noaa.gov WWW:LINK-1.0-http--link NOAA Office for Coastal Management Website NOAA Office for Coastal Management Home Page information custodian notPlanned https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/9606/supplemental/ak2019_kotlik_m9606.kmz This graphic displays the footprint for this lidar data set. kmz EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION theme Global Change Master Directory (GCMD) Science Keywords 23.3 CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALASKA VERTICAL LOCATION > LAND SURFACE place Global Change Master Directory (GCMD) Location Keywords 23.3 LIDAR > Light Detection and Ranging instrument Global Change Master Directory (GCMD) Instrument Keywords 23.3 Airplane > Airplane platform Global Change Master Directory (GCMD) Platform Keywords 23.3 Apoon Apoon Pass Chaniliut Kaelhuk Pass Kotlik Kotlik River Kvichvauk Pass Little Kotlik River Nelutahalik Creek Norton Sound Pastol Bay Pastoliak River Pastolik River Tatlalinguk Pass place Alaska Division of Geological & Geophysical Surveys Lidar - partner (no harvest) project InPort otherRestrictions This data set was compiled dynamically. It will be removed 10 days after 2026-06-21 from the NOAA system. Cite As: OCM Partners, [Date of Access]: 2019 AK DGGS Lidar: Kotlik, Alaska [Data Date Range], https://www.fisheries.noaa.gov/inport/item/68018. NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose. otherRestrictions This data set was compiled dynamically. It will be removed 10 days after 2026-06-21 from the NOAA system. Access Constraints: None otherRestrictions This data set was compiled dynamically. It will be removed 10 days after 2026-06-21 from the NOAA system. Use Constraints: Users should be aware that temporal changes may have occurred since this data set was collected and some parts of this data may no longer represent actual surface conditions. Users should not use this data for critical applications without a full awareness of its limitations. otherRestrictions This data set was compiled dynamically. It will be removed 10 days after 2026-06-21 from the NOAA system. 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. Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners. unclassified 2019 AK DGGS Lidar DEM: Kotlik, AK NOAA/NMFS/EDM 68000 crossReference vector eng; US elevation geoscientificInformation -163.659031 -163.005119 62.986807 63.111833 | Currentness: Ground Condition 2019-08-17 >classified point cloud data: Classified point cloud data is provided in this collection in compressed .laz format. Data are classified in accordance with ASPRS 2014 guidelines and contain return and intensity information. The average pulse spacing was 24.8 cm and the average density was 16.25 pts/m^2. Elevation surfaces interpolated from areas with a point density of fewer than 4pts/m2 were classified as nodata. >digital surface model: The DSM represents surface elevations, for example, heights of vegetation, buildings, bridges, etc. The DSM is a single band, 32-bit GeoTIFF file, with a ground sample distance of 0.5 meters. No Data value is set to -3.40282306074e+038. >digital terrain model: The DTM represents surface elevations of ground surfaces, excluding vegetation, bridges, buildings, etc. The DTM is a single-band, 32-bit float GeoTIFF file, with a ground sample distance of 0.5 meters. No Data value is set to -3.40282306074e+038. >lidar intensity image: The lidar intensity image describes the relative amplitude of reflected signals, contributing to the point cloud. Lidar intensity is largely 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 with a ground sample distance of 0.5 meters. No Data value is set to -3.40282306074e+038 (32-bit, floating-point minimum). >hydro-enforced digital terrain model: The hydro-enforced DTM represents bare earth surfaces which have undergone a selective "flattening" process, where elevation values for any hydrologic features, as well as any hydrologic obstacles (bridges, culverts, etc.), are replaced with neighboring pixel values. The hydro-enforced DTM is a single-band, 32-bit float GeoTIFF file, with a ground sample distance of 0.5 meters. No Data value is set to -3.40282306074e+038. Zip Zip LAS/LAZ - LASer Zip NOAA Office for Coastal Management (843) 740-1202 2234 South Hobson Ave Charleston SC 29405-2413 coastal.info@noaa.gov https://coast.noaa.gov WWW:LINK-1.0-http--link NOAA Office for Coastal Management Website NOAA Office for Coastal Management Home Page information distributor https://coast.noaa.gov/dataviewer/#/lidar/search/where:ID=9606/details/9606 WWW:LINK-1.0-http--link Customized Download Create custom data files by choosing data area, map projection, file format, etc. A new metadata will be produced to reflect your request using this record as a base. download https://noaa-nos-coastal-lidar-pds.s3.amazonaws.com/laz/geoid12b/9606/index.html WWW:LINK-1.0-http--link Bulk Download Bulk download of data files in the original coordinate system. download dataset Horizontal Positional Accuracy Horizontal accuracy was not measured for this collection. Vertical Positional Accuracy Forty-two bare earth checkpoints were used to determine the non-vegetated vertical accuracy (NVA) of the point cloud ground class, using a tin-based approach. Project NVA was calculated to have a root mean square error (RMSE) of 8.2 cm. Using the same approach, fifty-two vegetated points were used to determine the vegetated vertical accuracy (VVA) of the point cloud ground class. Project VVA was evaluated at 25.2 cm RMSE, with an average elevation difference of +21.2 cm. Completeness Report This data release is complete, and there is no over collect except for the aircraft turns that were eliminated from the dataset. Conceptual Consistency The data quality is consistent throughout the survey. The accompanying report provides additional detail regarding tests used to determine data fidelity. Data were collected by the Alaska Division of Geological and Geophysical Surveys (AK DGGS). OCM downloaded the data from the Alaska DGGS Elevation Portal and processed the data to be available for custom and bulk download from the NOAA Digital Coast Data Access Viewer (DAV). Airborne survey - DGGS operates a Riegl VUX1-LR lidar integrated with a GNSS and Northrop Grumman IMU system. The integration was designed by Phoenix LiDAR systems. The sensor is capable of collecting up to 820,000 points per second over a distance of 150 m. This survey was flown at a scan rate between 200,000 and 400,000 points per second at a scan rate between 80 and 150 lines per second. This survey was flown with an average elevation of 400 m above ground level and a ground speed of approximately 40 m/s with a fixed-wing aircraft configuration, using a Cessna 185 aircraft. The scan angle was set from 55 to 305 degrees. The total area surveyed was approximately 15 km2. The accompanying report provides additional detail regarding flight conditions. 2019-08-17T00:00:00 Ground survey - The Alaska Division of Mining, Land, and Water acquired surveyed ground control August 20-22, 2019 in an approximate 2-mile radius around the town of Kotlik. Ninety-four points were collected, including 42 bare earth, 18 forested, 33 low-vegetation, and 1 urban surface points. 2019-08-22T00:00:00 Lidar dataset processing - Point data were processed in SDCimport software for initial filtering and multiple-time-around (MTA) disambiguation. MTA errors, corrected in this process, are the result of imprecise interpretations of received pulse time intervals and occur more frequently with higher pulse refresh rates. IMU and GPS data were used to integrate flightline information with the point cloud in Spatial Explorer software. The point data were calibrated at an incrementally precise scale of sensor movement and behavior, incorporating sensor velocity, roll, pitch, and yaw fluctuations throughout the survey. Points were classified in accordance with ASPRS 2014 guidelines, using macros designed in Terrasolid software. Careful attention was given to the interpolation of the project's ground surface to compensate for inconsistent penetration through low vegetation as a function of the scan angle. Once classified, points underwent a geometric transformation and were converted from ellipsoidal heights to GEOID12B (Alaska) heights. Raster products were derived from the point cloud, using ArcMap. The DTM was interpolated from all ground class returns using a tin-based method. The DTM was also used to produce a separate hydroflattened raster, incorporating hydrography polygons from the AK SDMI IFSAR dataset. The DSM was likewise interpolated from only the first returns for all classes. An intensity image was also produced in ArcMap, using closest-to-mean binning. 2020-01-01T00:00:00 The NOAA Office for Coastal Management (OCM) downloaded 215 laz files from the Alaska DGGS Elevation Portal at: https://elevation.alaska.gov/. The files were in UTM Zone 3 NAD83 (2011), meters coordinates and were in NAVD88 (Geoid12b) elevations in meters. During processing, it was noted that there are lidar points that fall in water areas and on structures that are classified as ground. The point classifications were: 1 - Unclassified , 2 - Ground, 3 - Low Vegetation, 4 - Medium Vegetation, 5 - High Vegetation, 6 - Buildings and 7 - Low Noise. Classes available on the DAV are: 1, 2, 3, 4, 5, 6, 7. OCM performed the following processing on the data for Digital Coast storage and provisioning purposes: 1. An internal OCM script was run to check the number of points by classification and by flight ID and the gps and intensity ranges. 2. Internal OCM scripts were run on the laz files to convert from orthometric (NAVD88) elevations to ellipsoid elevations using the Geoid12b model, to convert from UTM Zone 3 NAD83 (2011), meters coordinates to geographic coordinates, to assign the geokeys, to sort the data by gps time and zip the data to database and to AWS S3. 2022-10-12T00:00:00 Office for Coastal Management processor Alaska Division of Geological and Geophysical Surveys (AK DGGS) AK DGGS https://elevation.alaska.gov/ WWW:LINK-1.0-http--link AK DGGS Elevation Portal Source Citation URL information originator The dataset has been mosaiced, reprojected, and clipped as needed from the original input files using PDAL and GDAL commands. 2026-06-21NOAA Office for Coastal Managementcoastal.info@noaa.govprocessor