gov.noaa.ngdc.mgg.dem:703 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact NCEI Contact Information Information for contacts at NCEI. information pointOfContact 2020-05-21 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) 3 row 9001 0.006666667 column 2701 0.0066666667 vertical 1 area true World Geodetic System 1984 WGS 84 2007-08-27 revision https://epsg.org/crs_4326/WGS-84.html WGS 84 GML of World Geodetic System 1984 coordinate reference system. information resourceProvider European Petroleum Survey Group https://epsg.org/home.html European Petroleum Survey Group Geodetic Parameter Registry Registry that accesses the EPSG Geodetic Parameter Dataset, which is a structured dataset of Coordinate Reference Systems and Coordinate Transformations. search publisher urn:ogc:def:crs:EPSG::4326 Mean Sea Level depth MSL depth 2012-08-10 revision https://epsg.org/crs_5715/MSL-depth.html MSL depth GML for Vertical CRS in EPGS Registry. information resourceProvider European Petroleum Survey Group https://epsg.org/home.html European Petroleum Survey Group Geodetic Parameter Registry Registry that accesses the EPSG Geodetic Parameter Dataset, which is a structured dataset of Coordinate Reference Systems and Coordinate Transformations. search publisher urn:ogc:def:crs:EPSG::5715 Southern Alaska Coastal Relief Model 2009-06-30 publication First International DOI Foundation (IDF) doi:10.7289/V58G8HMQ NOAA National Centers for Environmental Information NCEI Metadata ID: gov.noaa.ngdc.mgg.dem:703 NOAA National Centers for Environmental Information publisher NOAA National Geophysical Data Center author NOAA's National Geophysical Data Center (NGDC) is building coastal-relief models (CRM) for select U.S. coastal regions. Bathymetric, topographic, and shoreline data used in DEM compilation are obtained from various sources, including NGDC, the U.S. National Ocean Service (NOS), the National , the United States Geological Survey (USGS), the National Aeronautics and Space Administration, the Office of Coast Survey (OCS) and other federal, state, and local government agencies, academic institutions, and private companies. DEMs are referenced to the vertical tidal datum of Mean Sea Level (MSL) and horizontal datum of World Geodetic System 1984 (WGS 84). Grid spacings for the Southern Alaska CRM is 24 arc-seconds (~720 meters). The CRM provides a framework to enable scientists to model wave propagation and ocean circulation. In addition, it may be useful for benthic habitat research, weather forecasting, and environmental stewardship. completed historicalArchive NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact NCEI Contact Information Information for contacts at NCEI. information pointOfContact NOAA National Centers for Environmental Information DEM Information dem.info@noaa.gov pointOfContact asNeeded https://gis.ngdc.noaa.gov/arcgis/rest/directories/arcgisoutput/DEM_mosaics/DEM_global_mosaic_hillshade_ImageServer/_ags_c0493660_fa20_45af_835e_2525819b9eae.png Thumbnail of DEM JPG Earth Science > Oceans > Bathymetry/Seafloor Topography > Seafloor Topography Earth Science > Oceans > Bathymetry/Seafloor Topography > Bathymetry Earth Science > Oceans > Bathymetry/Seafloor Topography > Water Depth Earth Science > Land Surface > Topography > Terrain Elevation > Topographical Relief Maps Earth Science > Oceans > Coastal Processes > Coastal Elevation theme Global Change Master Directory (GCMD) Science Keywords 2024 revision 19 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Models/Analyses > DEM > Digital Elevation Model platform Global Change Master Directory (GCMD) Platform Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian ICSU-WDS > International Council for Science - World Data System project Global Change Master Directory (GCMD) Project Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian 1 meter - < 30 meters dataResolution Global Change Master Directory (GCMD) Horizontal Data Resolution Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian < 1 meter dataResolution Global Change Master Directory (GCMD) Vertical Data Resolution Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Coastal Relief Gridded elevations Integrated bathymetry and topography theme Uncontrolled Continent > North America > United States of America > Alaska Ocean > Pacific Ocean > North Pacific Ocean > Gulf of Alaska Vertical Location > Land Surface Vertical Location > Sea Floor place Global Change Master Directory (GCMD) Location Keywords 2024 revision 19 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Alaska Southern Alaska Gulf of Alaska Bering Sea Prince William Sound Aleutian Islands place Uncontrolled DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce dataCentre Global Change Master Directory (GCMD) Data Center Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian otherRestrictions Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives. otherRestrictions Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose. Not to be used for navigation. Although these data are of high quality and useful for planning and modeling purposes, they are not suitable for navigation. For navigation, please refer to the NOS nautical chart series. Produced by the NOAA National Centers for Environmental Information. Not subject to copyright protection within the United States. otherRestrictions Cite as: NOAA National Geophysical Data Center. 2009: Southern Alaska Coastal Relief Model. NOAA National Centers for Environmental Information. https://doi.org/10.7289/V58G8HMQ. Accessed [date]. Coastal Relief Model of Southern Alaska: Procedures, Data Sources, and Analysis 2011-06-24 publication https://www.ngdc.noaa.gov/mgg/dat/dems/regional_tr/crm_southak.pdf Coastal Relief Model of Southern Alaska: Procedures, Data Sources and Analysis Report describing the development of the Southern Alaska CRM download E. Lim originator B.W. Eakins originator R. Wigley originator 28 pages crossReference userGuide eng; USA oceans geoscientificInformation elevation 170 230 48.50 66.50 1888-01-01 2009-01-01 Digital Elevation Models: Color Shaded Relief ArcGIS Image Service 2011-10-19 creation DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://ngdc.noaa.gov/mgg/coastal/coastal.html HTTPS Integrated Models of Coastal Relief at NGDC Please see website for more information about Coastal DEMs. information publisher DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://noaa.maps.arcgis.com/home/item.html?id=feb3c625dc094112bb5281c17679c769 HTTPS NOAA GeoPlatform Entry for Digital Elevation Models Global Mosaic (Color Shaded Relief) NOAA GeoPlatform listing for Digital Elevation Models Global Mosaic (Color Shaded Relief) information publisher DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://noaa.maps.arcgis.com/home/item.html?id=d41f39c8a6684c54b62c8f1ab731d5ad ESRI:ArcGIS NOAA GeoPlatform Entry for DEM Footprints ArcGIS Map Service A map service showing the location and coverage of land and seafloor digital elevation models (DEMs) available. search publisher This is an ArcGIS image service showing color shaded relief visualizations of high-resolution digital elevation models (DEMs) of U.S. coastal regions. NOAA's National Geophysical Data Center (NGDC) builds and distributes high-resolution coastal digital elevation models (DEMs) that integrate ocean bathymetry and land topography to support NOAA's mission to understand and predict changes in Earth's environment, and conserve and manage coastal and marine resources to meet our Nation's economic, social, and environmental needs. They can be used for modeling of coastal processes (tsunami inundation, storm surge, sea-level rise, contaminant dispersal, etc.), ecosystems management and habitat research, coastal and marine spatial planning, and hazard mitigation and community preparedness. DEMs included in this visualization: High-resolution DEMs of select U.S. coastal communities and surrounding areas. Most are at a resolution of 1/3 to 1 arc-second (approx 10-30 m); U.S. Coastal Relief Model: A 3 arc-second (approx 90 m) comprehensive view of the conterminous U.S. coastal zone, Puerto Rico, and Hawaii; Southern Alaska Coastal Relief Model: A 24 arc-second (approx. 500 m) model of Southern Alaska, spanning the Bering Sea, Aleutian Islands, and Gulf of Alaska. This map service can be used as a basemap. It has a transparent background, so it can also be shown as a layer on top of a different basemap. Please see NGDC's corresponding DEM Footprints map service for polygon footprints and more information about the individual DEMs used to create this composite view. NCEI GIS Team NOAA National Centers for Environmental Information ncei.gis@noaa.gov pointOfContact DATA ANALYSIS AND VISUALIZATION > GEOGRAPHIC INFORMATION SYSTEMS > WEB-BASED GEOGRAPHIC INFORMATION SYSTEMS DATA MANAGEMENT/DATA HANDLING > DATA SEARCH AND RETRIEVAL DATA ANALYSIS AND VISUALIZATION > VISUALIZATION/IMAGE PROCESSING theme Global Change Master Directory (GCMD) Service Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian These data not to be used for navigation. Although these data are of high quality and useful for planning and modeling purposes, they are not suitable for navigation. For official navigation products, please refer to the U.S. nautical charts available from the NOAA Office of Coast Survey: http://www.nauticalcharts.noaa.gov. ArcGIS Image Service 10.7 1 -180 180 -90 90 tight ArcGIS for Server REST endpoint for image service https://gis.ngdc.noaa.gov/arcgis/rest/services/DEM_mosaics/DEM_global_mosaic_hillshade/ImageServer ESRI:ArcGIS ArcGIS Map Service Digital Elevation Models Global Mosaic (Color Shaded Relief) ArcGIS Image Service REST endpoint for Digital Elevation Models Global Mosaic (Color Shaded Relief) ArcGIS image service search WMS Get Capabilities https://gis.ngdc.noaa.gov/arcgis/rest/services/DEM_mosaics/DEM_global_mosaic_hillshade/ImageServer/WMSServer?request=GetCapabilities&service=WMS OGC:WMS Open Geospatial Consortium Web Map Service (WMS) Digital Elevation Models Global Mosaic (Color Shaded Relief) Web Map Service (WMS) Capabilities document for Open Geospatial Consortium Web Map Service for Digital Elevation Models Global Mosaic (Color Shaded Relief) search NCEI Digital Elevation Model Extents ArcGIS Feature Layer 2022-10-24 creation DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://www.ncei.noaa.gov/products/coastal-elevation-models HTTPS Coastal Elevation Models at NCEI information publisher DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://noaa.maps.arcgis.com/home/item.html?id=0afa88a1701749dbbf76fcadca4f77f3 HTTPS NOAA GeoPlatform Entry for NCEI Digital Elevation Model (DEM) Extents NOAA GeoPlatform listing for NCEI Digital Elevation Model (DEM) Extents information publisher DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://noaa.maps.arcgis.com/home/item.html?id=c876e3c96a8642ab8557646a3b4fa0ff HTTPS NOAA GeoPlatform Entry for DEM Global Mosaic (Elevation Values) NOAA GeoPlatform listing for DEM Global Mosaic (Elevation Values) information publisher DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://noaa.maps.arcgis.com/home/item.html?id=e11ebaeb19544bb18c2afe440f063062 HTTPS NOAA GeoPlatform Entry for DEM Global Mosaic (Color Shaded Relief) Shaded relief visualization of a global seamless bathymetry/topography mosaic of digital elevation models at NOAA/NCEI. information publisher DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, Department of Commerce https://noaa.maps.arcgis.com/home/item.html?id=e9ba2e7afb7d46cd878b34aa3bfce042 ESRI:ArcGIS Digital Elevation Models Mosaic (Individual DEMs) An image service providing access to bathymetric/topographic digital elevation models stewarded at NOAA's National Centers for Environmental Information. Either individual DEMs or small subsets can be accessed through this service. search publisher A map service showing the location and coverage of land and seafloor digital elevation models (DEMs) available from NOAA's National Centers for Environmental Information (NCEI). NCEI builds and distributes high-resolution, coastal digital elevation models (DEMs) that integrate ocean bathymetry and land topography to support NOAA's mission to understand and predict changes in Earth's environment, and conserve and manage coastal and marine resources to meet our Nation's economic, social, and environmental needs. They can be used for modeling of coastal processes (tsunami inundation, storm surge, sea-level rise, contaminant dispersal, etc.), ecosystems management and habitat research, coastal and marine spatial planning, and hazard mitigation and community preparedness. Layers available in the map service: Layers 1-4: DEMs by Category (includes various DEMs, both hosted at NCEI, and elsewhere on the web); Layers 6-11: NCEI DEM Projects (DEMs hosted at NCEI, color-coded by project); Layer 12: All NCEI Bathymetry DEMs (All bathymetry or bathy-topo DEMs hosted at NCEI). NCEI GIS Team NOAA National Centers for Environmental Information ncei.gis@noaa.gov pointOfContact DATA ANALYSIS AND VISUALIZATION > GEOGRAPHIC INFORMATION SYSTEMS > WEB-BASED GEOGRAPHIC INFORMATION SYSTEMS DATA MANAGEMENT/DATA HANDLING > DATA SEARCH AND RETRIEVAL DATA ANALYSIS AND VISUALIZATION > VISUALIZATION/IMAGE PROCESSING theme Global Change Master Directory (GCMD) Service Keywords 2020-01-09 publication 9.1 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2024. GCMD Keywords, Version 19. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian These data not to be used for navigation. Although these data are of high quality and useful for planning and modeling purposes, they are not suitable for navigation. For official navigation products, please refer to the U.S. nautical charts available from the NOAA Office of Coast Survey: https://www.nauticalcharts.noaa.gov. ArcGIS Feature Service 11.0 1 -180 180 -90 90 tight ArcGIS Server REST endpoint for feature service https://services2.arcgis.com/C8EMgrsFcRFL6LrL/arcgis/rest/services/ncei_dem_extents/FeatureServer HTTPS ESRI Feature Service REST Specification NCEI Digital Elevation Model (DEM) Extents ArcGIS Feature Service REST endpoint for NCEI Digital Elevation Model (DEM) Extents ArcGIS Feature Service search NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact NCEI Contact Information Information for contacts at NCEI. information distributor In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. netCDF 4 Classic https://www.ncei.noaa.gov/metadata/geoportal/rest/metadata/item/gov.noaa.ngdc.mgg.dem:703/html HTTPS Metadata Landing Page information https://www.ngdc.noaa.gov/thredds/dodsC/crm/crm_southak.nc.html OPeNDAP:OPeNDAP OPeNDAP Dataset Access Form OPeNDAP Dataset Access Form download https://www.ngdc.noaa.gov/thredds/fileServer/crm/crm_southak.nc HTTPS Download NetCDF File Download NetCDF File download https://www.ngdc.noaa.gov/thredds/wcs/crm/crm_southak.nc?service=WCS&version=1.0.0&request=GetCapabilities OGC:WCS Web Coverage Service GetCapabilities Web Coverage Service GetCapabilities information https://www.ngdc.noaa.gov/thredds/wms/crm/crm_southak.nc?service=WMS&version=1.3.0&request=GetCapabilities OGC:WMS Web Map Service GetCapabilities Web Map Service GetCapabilities information https://www.ngdc.noaa.gov/thredds/ncss/crm/crm_southak.nc/dataset.html HTTPS Download a subset of the NetCDF Download a subset of the NetCDF download https://www.ngdc.noaa.gov/thredds/ncml/crm/crm_southak.nc?catalog=https%3A%2F%2Fwww.ngdc.noaa.gov%2Fthredds%2Fcatalog%2Fcrm%2Fcatalog.html&dataset=crmDatasetScan%2Fcrm_southak.nc HTTPS NetCDF Markup Language file NetCDF Markup Language file information repository NOAA National Centers for Environmental Information NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015. 2015-04-22T00:00:00 dataset Horizontal Positional Accuracy Report The horizontal accuracy of bathymetric and topographic features in the DEM is dependent upon the DEM cell size and the accuracy of the input datasets used to determine corresponding cell values. Topography: NED 2 arc-second DEM: 60 meters, SRTM/CGIAR 3 arc-second DEM: 90 meters, NGDC GLOBE 30 arc-second DEM: 900 meters. DEM cell-value relative-contribution factors: NED 1/3 arc-second DEM: 10, SRTM/CGIAR DEM: 100, NGDC GLOBE DEM: 10. Bathymetry: a few tens of meters to several hundreds of meters. Positional accuracy of input bathymetric datasets limits accuracy of corresponding cell values in DEM. Recent NOS hydrographic data: about 1 meter. Early 20th-century NOS hydrographic soundings are limited by sparseness of deep-water soundings, and potentially large position accuracy of pre-satellite (i.e., GPS) navigation: tens to several hundreds of meters. NGDC multibeam sonar: about 300 meters Where present, recent NOS hydrographic survey data and NGDC multibeam supplant early 20th-centruy NOS hydrographic sounding. NOAA ENC's: ~500 to 1200 meters. NGDC Trackline: ~300 meters. NGDC ETOPO1: ~1800 meters. DEM cell-value relative-contribution factors: NOS hydrographic soundings: 10, NGDC Multibeam: 100, ENC soundings: 10, NGDC Trackline: 0.1, ETOPO1: 0.1. Positional accuracy of input bathymetric-topographic datasets limits accuracy of corresponding cell values in DEM. NGDC bathymetric-topographic DEMs: 30 to 240 meters. DEM cell-value relative-contribution factors: 100. Vertical Positional Accuracy Report The vertical accuracy of bathymetric and topographic features in the DEM is dependent upon the accuracy of the input datasets used to determine corresponding cell values. Topography: NED 2 arc-second DEM: +/- 2.44 meters, SRTM/CGIAR 3 arc-second DEM: +/-10 meters, NGDC GLOBE 30 arc-second DEM: +/- 10 to 250 meters. DEM cell-value relative-contribution factors: NED 2 arc-second DEM: 10, SRTM/CGIAR 3 arc-second DEM: 10, NGDC GLOBE 30 arc-second DEM: 1. Bathymetry: 30 meters to 5% of water depth. ENC soundings are sampled from the NOS hydrographic survey charts. Vertical accuracy of input bathymetric datasets limits accuracy of corresponding cells in DEM. GPS-navigated NGDC multibeam sonar sonar data: about 0.1 meter. Early 20th-century NOS hydrographic soundings and some NGDC marine trackline geophysics data are limited by sparseness of deep-water soundings, and potentially large position accuracy of pre-satellite (i.e., GPS) navigation: several tens of meters. Where present, recent NOS hydrographic data supersede early 20th-centruy NOS hydrographic sounding data values in the DEM. The vertical accuracy of ETOPO1 is dependent upon the data sets used to determine corresponding DEM cell values. DEM cell relative-contribution factors: NOS hydrographic soundings: 10, NGDC multibeam: 100, ENC soundings: 10. Gridding interpolation to determine cell values between sparse NOS hydrographic soundings degrades the vertical accuracy of elevations. Bathymetry-topography: NGDC bathymetric-topographic DEMs: dependent upon input datasets. NGDC made every effort to obtain all available digital topographic and bathymetric datasets in the region for use in building the DEM. Datasets were visually compared internally and externally (with other overlapping datasets and satellite images and maps) in ESRI ArcGIS and Applied Imagery QT Modeler for identification of anomalous elevations or data inconsistencies. Where elevation inconsistencies occurred, the most recent and/or highest resolution data set was selected for use in that region. Elevations in the older and/or lower-resolution datasets were deleted prior to building the DEM. All datasets obtained by NGDC were converted to common horizontal datum of WGS 84 geographic using FME or ArcGIS. They were also converted to common file format, ESRI point shapefiles or digital rasters, for visualization and inspection. 2008-06-15T00:00:00 Barry W. Eakins NOAA National Centers for Environmental Information Research Scientist 303-497-6505 325 Broadway, E/GC3 Boulder Colorado 80305-3328 USA Barry.Eakins@noaa.gov 9am-5pm, M-F, Mountain Time Contact Marine Geology and Geophysics Division pointOfContact Datasets were visually inspected with ArcGIS and QT Modeler for identification and editing of data anomalies. Datasets were then compared with overlapping datasets to ensure data consistency. 2008-07-02T00:00:00 xyz files of the bathymetric data were surfaced using GMT's 'surface' tool onto a 20 arc-second grid that interpolated to fill empty cells. Points extracted every 10 meters along the coastline were also included to ensure that the bathymetric grid reached zero at the coast. The resulting Arc ASCII grid was imported into ArcGIS and clipped to the coastline to remove values over land. 2009-02-15T00:00:00 xyz files for each input dataset were gridded using MB-System's 'mbgrid' tool, which utilizes a high-tension spline interpolation method to fill grid cells with no input elevation values. Preferential weighting was given to more recent, higher-accuracy datasets. Gridding was performed in quadrants, each with a 5% data buffer. The grids were imported in ArcGIS and seamlessly merged to create the final DEM. 2009-05-20T00:00:00 The DEM was quantitatively evaluated by comparing the grid against source data files. 2009-05-30T00:00:00 Source Contribution: hydrographic surveys ; Source Type: online NOS Hydrographic Surveys 2009-01-01 publication NOAA National Geophysical Data Center originator https://www.ngdc.noaa.gov/mgg/bathymetry/hydro.html NOS Hydrographic Survey Database Digital database of NOS hydrographic surveys that date back to the late 19th century. download 1888-01-01 2005-01-01 Source Contribution: Multibeam bathymetry data ; Source Type: online NGDC Multibeam Bathymetry Database 2008-01-01 publication NOAA National Geophysical Data Center originator https://www.ngdc.noaa.gov/mgg/bathymetry/multibeam.html NGDC Multibeam Bathymetry Database Multibeam swath sonar survey data download 1986-01-01 2005-01-01 Source Contribution: ENC soundings extracted from NOS charts ; Source Type: web Electronic Navigational Chart (ENC) soundings 2009-01-01 publication OCS > NOAA Office of Coast Survey originator http://www.nauticalcharts.noaa.gov/mcd/enc/index.htm Electronic Navigational Chart (ENC) soundings ENC soundings extracted from NOS charts download 2008-01-01 Source Contribution: gridded topography ; Source Type: online Shuttle Radar Topography Mission (SRTM) processed by CGIAR 2008-01-01 publication NASA > National Aeronautics and Space Administration originator http://srtm.csi.cgiar.org/ Shuttle Radar Topography Mission/CGIAR global topography download 2000-01-01 Source Contribution: bathymetry and topography ; Source Type: online NGDC ETOPO1 2008-01-01 publication NOAA National Geophysical Data Center originator https://www.ngdc.noaa.gov/mgg/global/global.html NGDC ETOPO1 Integrated bathymetric-topographic global DEM download 2007-01-01 2008-01-01 Source Contribution: Topographic DEM ; Source Type: online USGS NED topography 2008-01-01 publication USGS > United States Geological Survey originator http://seamless.usgs.gov/ USGS National Elevation Dataset Digital database of U.S. topography, in raster form (DEM) download 1999-01-01 2003-01-01 Source Contribution: NGDC Bathymetric-topographic DEMs ; Source Type: online NGDC Bathymetric-topographic DEMs 2009-01-01 publication NOAA National Geophysical Data Center originator https://www.ngdc.noaa.gov/mgg/inundation/tsunami/ NGDC Bathymetric-topographic DEMs Integrated bathymetric-topographic DEMs download 2006-01-01 2009-01-01 Source Contribution: composite shoreline ; Source Type: online U.S. Fish and Wildlife Service coastline 2006-01-01 publication U.S. FWS > United States Fish and Wildlife Service originator http://www.fws.gov/ Seamless digital coastline of the state of Alaska compiled from a variety of sources. The U.S. Fish and Wildlife Service has compiled a seamless digital coastline of the State of Alaska from a variety of sources, including: the National Hydrography Dataset, NOAA nautical charts, U.S. Fish and Wildlife Service, National Geographic Topo Software, U.S. Army Corps of Engineers, and Alaska Department of Natural Resources. download 1995-01-01 2006-01-01 Source Contribution: shoreline ; Source Type: online NGA Global Shoreline 2000-01-01 publication NGA > National Geospatial-Intelligence Agency originator http://msi.nga.mil/NGAPortal/MSI.portal National Geospatial-Intelligence Agency The NGA Global Shoreline Data is an unclassified vector dataset generated by Earth Satellite Corporation download 1998-01-01 2002-01-01 Source Contribution: shoreline ; Source Type: online Global Self-consistent, Hierarchical, High-resolution Shoreline (GSHHS) 2005-01-01 publication NGDC > National Geophysical Data Center originator https://www.ngdc.noaa.gov/mgg/shorelines/gshhs.html National Geophysical Data Center GSHHS is a high-resolution shoreline data set created from two well-known, public domain data sets. download 2003-01-01 2010-01-01 asNeeded Modified for compliance to NCEI Template v1.2.