Color Shaded Relief of Idaho with a Horizontal Grid Spacing of 30-meters

Color Shaded Relief of Idaho with a Horizontal Grid Spacing of 30-meters

Frequently-asked questions:

What does this data set describe?

Title:
Color Shaded Relief of Idaho with a Horizontal Grid Spacing of 30-meters

Abstract: 
The 30-meter Color Shaded Relief of Idaho data set was derived from the 1 arc second National Elevation Dataset and USGS DEM elevation data. The NED is a seamless mosaic of best-available elevation data. The 7.5-minute elevation data for the conterminous United States are the primary initial source data. In addition to the availability of complete 7.5-minute data, efficient processing methods were developed to filter production artifacts in the existing data, convert to the NAD83 datum, edge-match, and fill slivers of missing data at quadrangle seams. One of the effects of the NED processing steps is a much-improved base of elevation data for calculating slope and hydrologic derivatives. The specifications for the NED 1 arc second and 1/3 arc second data are: Geographic coordinate system Horizontal datum of NAD83, except for AK which is NAD27 Vertical datum of NAVD88, except for AK which is NAVD29 Z units of meters.

  1. How should this data set be cited?

    Idaho Geospatial Data Clearinghouse, 20041101, Color Shaded Relief of Idaho with a Horizontal Grid Spacing of 30-meters: Idaho Geospatial Data Clearinghouse, Moscow, ID USA.

    Online links:
  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -117.532059
    East: -110.655139
    North: 49.039808
    South: 41.945007

  3. What does it look like?

    Thumbnail image:

  4. Does the data set describe conditions during a particular time period?

    Beginning date: 1999
    Ending date: unknown
    Currentness reference: 
    publication date

  5. What is the general form of this data set?

    Geospatial data presentation form: raster digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      This is a Raster data set. It contains the following raster data types:
      • Dimensions 26117 x 16769 x 1, type Pixel

    2. What coordinate system is used to represent geographic features?

      The map projection used is Transverse Mercator.

      Projection parameters:
      Transverse Mercator
      Scale factor at central meridian: 0.999600
      Longitude of central meridian: -114.000000
      Latitude of projection origin: 42.000000
      False easting: 2500000.000000
      False northing: 1200000.000000

      Planar coordinates are encoded using row and column.
      Abscissae (x-coordinates) are specified to the nearest 30.000000.
      Ordinates (y-coordinates) are specified to the nearest 30.000000.
      Planar coordinates are specified in meters.

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

  7. How does the data set describe geographic features?

    Entity and attribute overview: 
    Shaded relief TIFF w/ world file (.tif & .tfw) image grid cells having 0 - 255 3-band red-green-blue values

    Entity and attribute detail citation: 
    None
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Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)

    • Idaho Geospatial Data Clearinghouse

  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    Bruce Godfrey
    Idaho Geospatial Data Clearinghouse
    GIS Specialist
    Box 442350
    Moscow, ID 83844-2350
    USA

    208.885.6463 (voice)
    bgodfrey@uidaho.edu
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Why was the data set created?

The 30-meter Shaded Relief image was developed to portray the terrain of Idaho in color. It is intended for visual purposes only. The original NED & DEM data must be used for conducting analysis and determining elevation values. No responsibility is assumed by the Idaho Geospatial Data Clearinghouse in the use of these data.

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How was the data set created?

  1. Where did the data come from?

    ELEV30m_id (source 1 of 2)

    Idaho Geospatial Data Clearinghouse, 20041101, Digital Elevation of Idaho at 30-meter Resolution: Idaho Geospatial Data Clearinghouse, Moscow, ID USA.

    Type of source media: online
    Source contribution: 
    Digital elevation data for Idaho at a 30-meter horizontal grid spacing.

    SHDRLFGRAYSCALE (source 2 of 2)

    Idaho Geospatial Data Clearinghouse, 20041101, Grayscale Shaded Relief of Idaho with a Horizontal Grid Spacing of 30-meters: Idaho Geospatial Data Clearinghouse, Moscow, ID USA.

    Type of source media: online
    Source contribution: 
    Grayscale Shaded Relief of Idaho derived from the National Elevation Dataset and USGS DEM elevation data.

  2. What changes have been made?

    Date: 20041101 (change 1 of 1) 
    All processing was done using ArcView 3.3

The source elevation grid was added to a view and a legend file (SM08group5.avl) was applied. This legend file was part of the ShadeMax set developed by Jim Mossman and available on the ESRI Scripts web site. The source grayscale shaded relief was used as a brightness theme (15 / 85) and the image was output as a TIFF using the 'Image Conversion-Georeferencing' extension available on the ESRI Scripts web site. White was choosen as the background color.

    Person responsible for change:
    Bruce Godfrey
    Idaho Geospatial Data Clearinghouse
    GIS Specialist
    Box 442350
    Moscow, ID 83844-2350
    USA

    208.885.6463 (voice)
    bgodfrey@uidaho.edu

    Data sources used in this process:
    • ELEV30m_ID
    • SHDRLFGRAYSCALE

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How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

  2. How accurate are the geographic locations?

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    Data completeness reflects the content of the original NED elevation data.

  5. How consistent are the relationships among the observations, including topology?

    No tests for logical consistency have been performed on this data set.

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How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access constraints: None
Use constraints: 
None

Distributor 1 of 1

  1. Who distributes the data set?

    Bruce Godfrey
    Idaho Geospatial Data Clearinghouse
    GIS Specialist
    Box 442350
    Moscow, ID 83844-2350
    USA

    208.885.6463 (voice)
    bgodfrey@uidaho.edu

  2. What's the catalog number I need to order this data set?

    Downloadable Data

  3. What legal disclaimers am I supposed to read?

    Although these data have been processed successfully on a computer system at the Idaho Geospatial Data Clearinghouse, no warranty, expressed or implied, is made regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty.

  4. How can I download or order the data?

  5. Is there some other way to get the data?

  6. What hardware or software do I need in order to use the data set?

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Who wrote the metadata?

Dates:
Last modified: 20041102

Metadata author:
Bruce Godfrey
Idaho Geospatial Data Clearinghouse
GIS Specialist
Box 442350
Moscow, ID 83844-2350
USA

208.885.6463 (voice)
bgodfrey@uidaho.edu

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata(FGDC-STD-001-1998)

Metadata extensions used:
  • http://www.esri.com/metadata/esriprof80.html

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