NCEI (formerly NGDC)
EMMA logo
View Metadata As: Get Data, FAQ, HTML, 19139 XML
Assess Metadata For: Completeness, DOI Readiness, CSW Readiness, Components

Homer, Alaska 1 arc-second DEM

The 1-second Homer Alaska Elevation Grid provides bathymetric data in ASCII raster format of .89-second resolution in geographic coordinates. This grid is strictly for tsunami inundation modeling
Cite this dataset when used as a source.
Online Access
Distribution Formats
  • ESRI Arc ASCII (Version: 1)
    • File Specification: ASCII text version of ESRI ArcGIS raster format
    • File Compression: WINZIP
Distributor DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
Dataset Publisher NOAA Center for Tsunami Research
NOAA/PMEL/Center for Tsunami Research (NCTR)
Documentation links not available.
  • publication: 2002-01-01
Edition: 2002
Data Presentation Form: mapDigital
Dataset Progress Status Complete
Data Update Frequency: Irregular
Supplemental Information:
This grid was developed through funding from the National Tsunami Hazard Mitigation Program. It will be updated as better data become available.
Purpose: This grid was constructed for use in tsunami inundation modeling
Use Limitations
  • 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 Geophysical Data Center. Not subject to copyright protection within the United States.
  • While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
Dataset acknowledgements not available.
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
  • NOAA/PMEL/Center for Tsunami Research (NCTR)
Time Period: Unknown to Unknown
Spatial Reference System: urn:ogc:def:crs:EPSG::4326 urn:ogc:def:datum:EPSG::5868
Spatial Bounding Box Coordinates:
N: 59.67
S: 59.58
E: -151.37
W: -151.56
Spatial Coverage Map:
Theme keywords
  • DEM > Digital Elevation Model
  • H: 1 meter - < 30 meters
  • V: < 1 meter
  • Coastal Relief
  • Gridded elevations
Data Center keywords
  • 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
Place keywords
  • Continent > North America > United States of America > Southcentral Alaska
  • Homer
  • Kenai Peninsula Borough
  • Cook Inlet
  • Kachemak Bay
Project keywords
  • ICSU-WDS > International Council for Science - World Data System
  • Earth Science > Oceans > Bathymetry/Seafloor Topography > Seafloor Topography
  • Earth Science > Oceans > Bathymetry/Seafloor Topography > Bathymetry
  • Earth Science > Oceans > Bathymetry/Seafloor Topography > Water Depth
Use Constraints No constraint information available
Fees Fee information not available.
Lineage information for: repository
Processing Steps
  • 2015-04-22T00:00:00 - 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.
Lineage information for: dataset
  • NOAA/PMEL/Center for Tsunami Research (NCTR)
  • NOAA/PMEL/Center for Tsunami Research (NCTR)
Processing Steps
  • Each raw data source was converted into ESRI ArcGIS formats. The resulting files were converted and adjusted to predetermined projection (geographic), horizontal datum (NAD27), and vertical datum (MHW) using the ArcInfo PROJECT command and ArcView Spatial Analyst MAP CALCULATOR algorithm. A polyline shapefile was created to represent the coastline. The coastline is a culmination of USGS hydrographic vectors, USACE marina data, and local photogrammetric data. A TIN (Triangulated Irregular Network) was created using bathymetric data points and coastline points using ArcInfo CREATETIN. A 0.88-second grid was created using TINLATTICE. The data was assessed for quality using ArcView Spatial Analyst. The grid was compared to its raw dataset. The 0.88-second grid was clipped to requested coordinates. 62 analog photogrammetric maps were scanned into TIFF format by the Alaska Tsunami Mapping Team and transferred to the NOAA Center for Tsunami Inundation Mapping Efforts. The TIFF files were georeferenced and 2-foot topographic contours from 38 images covering the Homer region area were digitized. The contours were converted to predetermined vertical datum and units. A TIN was created using the digitized contours, USACE topographic points and contours, USGS DRG 10-meter contours, and coastline using ArcInfo CREATETIN. A 0.88-second topographic grid was created using TINLATTICE and clipped to requested coordinates. The data were assessed for quality using ArcView Spatial Analyst by comparing raw datasets. The topographic grid was updated with the Aeromap U.S. LIDAR data. The LIDAR data grid was analyzed for quality and converted to predetermined projection, datum, and resolution. The LIDAR data was compared to other topographic data sources and then merged with the original grid, superseding earlier data. Consistency between the LIDAR coverage area and older topographic data was verified. The final topographic grid was analyzed for quality. The topographic and bathymetric grids were merged into a single grid and analyzed for quality. Data were assessed for quality by comparing with original sources, corresponding sources, and control data. Continuity between old and new data were assessed and errors were corrected. The final grid was analyzed for blunders, systematic errors, and logical consistency.
  • 2008-11-04T00:00:00 - Metadata imported.
Processing Environment
Source Datasets
  • GEODAS Vol 2, Ver 4.1 and Global Relief
    • Description of Source: Source Contribution: bathymetric data values; Source Type: online
    • Temporal extent used: 1890-01-01 to 2001-01-01
  • 1:25000 and 1:63360 hydrographic vectors, 7.5-minute digital raster graphics
    • Description of Source: Source Contribution: topographic elevation contours and shoreline; Source Type: online
    • Temporal extent used: 1982-01-01 to 1982-01-01
Last Modified: 2015-09-03
For questions about the information on this page, please email: