2019 USACE NCMP Topobathy Lidar DEM: Alaska ak2019_usace_dem_m9055_metadata eng Dataset DOD/USARMY/USACE/SAM/MOBILE/OPJ/JALBTCX > Joint Airborne Lidar Bathymetry Technical Center of Expertise, Mobile District, South Atlantic Division, U.S. Army Corps of Engineers, U.S. Army, U.S. Department of Defense EARTH SCIENCE > HUMAN DIMENSIONS > ENVIRONMENTAL GOVERNANCE/MANAGEMENT > LAND MANAGEMENT > LAND USE CLASSES EARTH SCIENCE > LAND SURFACE > GEOMORPHIC LANDFORMS/PROCESSES > COASTAL LANDFORMS EARTH SCIENCE > LAND SURFACE > GEOMORPHIC LANDFORMS/PROCESSES > COASTAL PROCESSES EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > BATHYMETRY EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > SEAFLOOR TOPOGRAPHY EARTH SCIENCE > OCEANS > COASTAL PROCESSES > COASTAL ELEVATION elevation imageryBaseMapsEarthCover oceans CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA CONTINENT > NORTH AMERICA > UNITED STATES OF AMERICA > ALASKA VERTICAL LOCATION > LAND SURFACE VERTICAL LOCATION > SEA FLOOR LIDAR > Light Detection and Ranging Airplane > Airplane U.S. Army Corps of Engineers (USACE) 2019 July These files contain rasterized topobathy lidar elevations generated from data collected by the Coastal Zone Mapping and Imaging Lidar (CZMIL) system. CZMIL integrates a lidar sensor with simultaneous topographic and bathymetric capabilities, a digital camera and a hyperspectral imager on a single remote sensing platform for use in coastal mapping and charting activities. Native lidar data is not generally in a format accessible to most Geographic Information Systems (GIS). Specialized in-house and commercial software packages are used to process the native lidar data into 3-dimensional positions that can be imported into GIS software for visualization and further analysis. Horizontal positions, provided in decimal degrees of latitude and longitude, are referenced to the North American Datum of 1983 National Adjustment of 2011 (NAD83 (2011)). Vertical positions are referenced to the NAD83 (2011) ellipsoid and provided in meters. The National Geodetic Survey's (NGS) GEOID12B model is used to transform the vertical positions from ellipsoid to orthometric heights referenced to the North American Vertical Datum of 1988 (NAVD88). The 3-D position data are sub-divided into a series of LAS files, which are tiled into 1-km by 1-km boxes defined by the Military Grid Reference System. The LAS file index is provided by the shape files, "MGRS_1km_04V.shp ", and the numbers used to identify files are in the "Box" field of the shape file. The data file naming convention is based on the year, effort, area, "Box" number and data product type. An example file name is "2019_NCMP_AK_04VDR0987_BareEarth_1mGrid.tif", where 2019 is the year of data collection, NCMP is the effort under which data were collected, AK is the area of data collection, 04VDR0987 is the "Box" number and BareEarth_1mGrid is the data product type. In addition to these bare earth Digital Elevation Model (DEM) data, the lidar point data that these DEM data were created from, are also available. These data are available for custom download at the link provided in the URL section of this metadata record. DEMs that were created from all classes of points (1, 2, 29) at a 1 meter grid size are available by request via email at: coastal.info@noaa.gov. These products have not been reviewed by the NOAA Office for Coastal Management (OCM) and any conclusions drawn from the analysis of this information are not the responsibility of NOAA or OCM. OCM Partners OCM Partners https://www.fisheries.noaa.gov/inport/item/59419 https://www.fisheries.noaa.gov/inport/item/49404 https://www.fisheries.noaa.gov/inport/item/59331 northlimit=68.361331; eastlimit=-134.637251; southlimit=56.222919; westlimit=-168.96509; start=2019-07-09; end=2019-07-28; These data have been developed from the best available sources. Although efforts have been made to ensure that the data are accurate and reliable, errors and variable conditions originating from physical sources used to develop the data may be reflected in the data supplied. Users must be aware of these conditions and bear responsibility for the appropriate use of the information with respect to possible errors, scale, resolution, rectification, positional accuracy, development methodology, time period, environmental and climatic conditions and other circumstances specific to these data. The user is responsible for understanding the accuracy limitations of the data provided herein. The burden for determining fitness for use lies entirely with the user. The user should refer to the accompanying metadata notes for a description of the data and data development procedures. 2020