# Canadian Digital Elevation Data, Level 1 (CDED1)
116B

1. Identification Information
2. Data Quality Information
3. Spatial Data Organization Information
4. Spatial Reference Information
5. Entity and Attribute Information
6. Distribution Information
7. Metadata Reference Information

## Identification Information

Citation:
  Citation Information:
    Originator:
      Centre for Topographic Information - Geomatics Canada - Ottawa
    Publication Date:
      1997-07-15
    Title:
      116B
    Edition:
      Dataset: 1.0 Metadata: 2
    Geospatial Data Presentation Form:
      raster digital data
    Series Information:
      Series Name:
        Canadian Digital Elevation Data, Level 1 (CDED1)
      Issue Identification:
        None
    Publication Information:
      Publication Place:
        Sherbrooke, Quebec, Canada
      Publisher:
        Government of Canada, Natural Resources Canada, Centre for Topographic Information
    Other Citation Details:
      English, GeoBase
    Online Linkage:
      http://www.GeoBase.ca

Description:
  Abstract:
    The Centre for Topographic Information (CTI) jointly produces the CDED with federal, provincial and territorial government agencies as well as the private sector.
    A CDED consists of an ordered array of ground or reflective surface elevations, recorded in metres, at regularly spaced intervals. The source digital data for CDED is extracted from the hypsographic and hydrographic elements of the National Topographic Data Base (NTDB) at scales of 1:50 000 and 1:250 000, or the Geospatial Data Base (GDB), or various scaled positional data acquired by the provinces and territories, or remotely sensed imagery.
  Purpose:
    CDED plays the same role as contours and relief shading on conventional paper maps. CDED serves as a key primary data in a range of applications critical to achieving sustainable development.
    These applications include environmental and ecological impact assessments, water flow and water quality analysis, climate change studies, forest regeneration planning and wildlife habitats.
    In addition, CDED can be used in the generation of three-dimensional graphics displaying terrain slope, profiles and line of sight. Non-graphic applications include geoid calculations, terrain modelling, flood simulations and telecommunication studies.
  Supplemental Information:
    Minimum Elevation (Z): 231 metres
    Maximum Elevation (Z): 2327 metres
    Elevation Type: ground

Time Period of Content:
  Time Period Information:
    Range of Dates/Times:
      Beginning Date:
        1986-01-01
      Ending Date:
        1986-01-01
  Currentness Reference:
    Ground condition and/or production

Status:
  Progress:
    Complete
  Maintenance and Update Frequency:
    As needed

Spatial Domain:
  Bounding Coordinates:
    West Bounding Coordinate:
      -140
    East Bounding Coordinate:
      -138
    North Bounding Coordinate:
      65
    South Bounding Coordinate:
      64

Keywords:
  Theme:
    Theme Keyword Thesaurus:
      GCMD
    Theme Keyword:
      EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > CONTOURS
    Theme Keyword:
      EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TERRAIN ELEVATION > DEM
    Theme Keyword:
      EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TOPOGRAPHIC RELIEF > DEM
    Theme Keyword:
      EARTH SCIENCE > LAND SURFACE > TOPOGRAPHY > TOPOGRAPHIC EFFECTS
    Theme Keyword:
      DEM
    Theme Keyword:
      DTM
    Theme Keyword:
      ELEVATION
  Place:
    Place Keyword Thesaurus:
      CEONET
    Place Keyword:
      Continent > North America > Canada > Yukon Territory
    Place Keyword:
      DAWSON
    Place Keyword:
      116B

Access Constraints:
  Data are subject to the GeoBase Unrestricted Use Licence Agreement (http://www.GeoBase.ca - in the Data section).

Use Constraints:
  Data are subject to the GeoBase Unrestricted Use Licence Agreement (http://www.GeoBase.ca - in the Data section).

Point of Contact:
  Contact Information:
    Contact Organization Primary:
      Contact Organization:
        Government of Canada, Natural Resources Canada, Centre for Topographic Information
      Contact Person:
        GeoBase Technical Support
    Contact Address:
      Address Type:
        mailing and physical
      Address:
        2144, King Street West, Suite 010
      City:
        Sherbrooke
      State or Province:
        Quebec
      Postal Code:
        J1J 2E8
      Country:
        Canada
    Contact Voice Telephone:
      +01-819-564-4857 / 1-800-661-2638 (Canada and USA)
    Contact Facsimile Telephone:
      +01-819-564-5698
    Contact Electronic Mail Address:
      SupportGeoBase@NRCan.gc.ca
    Hours of Service:
      8:30 to 12:00 and 13:00 to 16:30 EST

Data Set Credit:
  Centre for Topographic Information - Geomatics Canada

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## Data Quality Information

Logical Consistency Report:
  Canada's coastline, oceans and estuaries at mean sea level, are assigned an elevation value of zero metres. However, the Nova Scotia coastline, oceans, and estuaries are depicted at the mean high water level (MHWL), which has varying elevations across the province. All MHWL elevation values are with reference to the Canadian Vertical Geodetic Datum 1928 (CVGD28).
  For CDED produced using ground elevations, water bodies are naturally occurring areas of constant elevation (lakes) or having a small slope (rivers). Water bodies are assigned their known elevations or estimated values. Lakes are represented flatter and lower than the surrounding terrain (one elevation per lake) and the shore must be clearly discernible. A water body of unknown elevation is assigned an interpolated elevation that is at least one metre lower than the contour elevation surrounding its shores. Drainage (rivers and streams) must be continuous (no gaps), have constant water flow and a descending order of z-values.
  For CDED produced using reflective surface elevations, water bodies (lakes) may not have a constant elevation. They may have a small slope to indicate the direction of the water flow.
  Quality control must assure that the CDED is smooth within the grid and continuous from node to node, except at natural break points such as streams, cliffs, and craters.

Completeness Report:
  The content of the CDED1 data sets is constant since the number of elevation points per profile and the number of profiles per cell are constant for all CDED1 files (1201 x 1201).

Positional Accuracy:
  Horizontal Positional Accuracy:
    Horizontal Positional Accuracy Report:
      Accuracy evaluation is related to the data source(s) used to generate the CDED.
      National Topographic Data Base Data Source:
      Planimetric data accuracy is expressed as the circular map accuracy standard (CMAS) of topographic feature derived from the equation below:
      Standard circular error:
      σc = 0.7071 √(σx² + σy²)
      σx = standard deviation in the X-axis
      σy = standard deviation in the Y-axis
      Circular map accuracy standard: CMAS = 2.1460 σc.
    Quantitative Horizontal Positional Accuracy Assessment:
      Horizontal Positional Accuracy Value:
        250
      Horizontal Positional Accuracy Explanation:
        Circular Map Accuracy Standards (CMAS) for NTDB sources from Centre for Topographic Information (in metres).
  Vertical Positional Accuracy:
    Vertical Positional Accuracy Report:
      Accuracy evaluation is related to the data source(s) used to generate the CDED.
      National Topographic Data Base Data Source:
      Altimetric accuracy of source material is expressed as the Linear Map Accuracy Standard (LMAS) in the same measuring unit method of NTDB data, obtained according to the equation below:
      Linear map accuracy standard: LMAS = 1.6449 σz
      σz = standard deviation of the elevation.
    Quantitative Vertical Positional Accuracy Assessment:
      Vertical Positional Accuracy Value:
        -1
      Vertical Positional Accuracy Explanation:
        The value "-1" is indicated when vertical positional accuracy is unknown.

Lineage:
  Source Information:
    Source Citation:
      Citation Information:
        Originator:
          Government of Canada, Natural Resources Canada, Center for Topographic Information
        Publication Date:
          1993-07-09
        Title:
          National Topographic Data Base - 116B-1.0
    Source Scale Denominator:
      250000
    Type of Source Media:
      Digital
    Source Time Period of Content:
      Time Period Information:
        Range of Dates/Times:
          Beginning Date:
            1986-01-01
          Ending Date:
            1986-01-01
      Source Currentness Reference:
        publication date
    Source Citation Abbreviation:
      NTDB - 116B
    Source Contribution:
      The hypsographic and hydrographic elements of the source NDTB were used to produce the CDED. Special care was taken with regard to watercourse direction of flow and the flatness of the water surface.
  Process Step:
    Process Description:
      The steps undertaken by the Canadian Forestry Service to generate CDED derived from NTDB 1:250 000 are:1) Flow directionality is applied to the stream coverage using the lake and contour data (arcs pointing downstream), maintaining a connected hydrographic network.2) Incongruities in the NTDB hydrography and hypsography including the problems in the edgematching with the 9 surrounding tiles are identified and corrected.3) Elevations on lake polygons corresponding to the lake elevations recorded on the paper map are tagged.4) A DEM using ANUDEM version 5 with hydrographic network, contours, and elevation points as input data, are produced.5) Quality Control on the DEM are conduce.6) The DEM is converted to CDED format. For the final CDED, an automatic inspection is conducted by the Centre for Topographic Information Sherbrooke prior to archiving.
    Process Date:
      1997-07-15

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## Spatial Data Organization Information

Direct Spatial Reference Method:
  Raster

Raster Object Information:
  Raster Object Type:
    Grid Cell
  Row Count:
    1201
  Column Count:
    1201

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## Spatial Reference Information

Horizontal Coordinate System Definition:
  Geographic:
    Latitude Resolution:
      3
    Longitude Resolution:
      3
    Geographic Coordinate Units:
      Decimal seconds
  Geodetic Model:
    Horizontal Datum Name:
      North American Datum of 1983
    Ellipsoid Name:
      Geodetic Reference System 1980
    Semi-major Axis:
      6378137
    Denominator of Flattening Ratio:
      298.257222101

Vertical Coordinate System Definition:
  Altitude System Definition:
    Altitude Datum Name:
      Mean sea level (MSL) / Canadian Vertical Geodetic Datum of 1928 (CVGD28)
    Altitude Resolution:
      1
    Altitude Distance Units:
      metres
    Altitude Encoding Method:
      Implicit coordinate

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## Entity and Attribute Information

Overview Description:
  Entity and Attribute Overview:
    See details citation
  Entity and Attribute Detail Citation:
    Natural Resources Canada, Canadian Digital Elevation Data, Standards and Specifications, September 2000.

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## Distribution Information

Distributor:
  Contact Information:
    Contact Organization Primary:
      Contact Organization:
        Government of Canada, Natural Resources Canada, Centre for Topographic Information
      Contact Person:
        GeoBase Technical Support
    Contact Address:
      Address Type:
        mailing and physical
      Address:
        2144, King Street West, Suite 010
      City:
        Sherbrooke
      State or Province:
        Quebec
      Postal Code:
        J1J 2E8
      Country:
        Canada
    Contact Voice Telephone:
      +01-819-564-4857 / 1-800-661-2638 (Canada and USA)
    Contact Facsimile Telephone:
      +01-819-564-5698
    Contact Electronic Mail Address:
      SupportGeoBase@NRCan.gc.ca
    Hours of Service:
      8:30 to 12:00 and 13:00 to 16:30 EST

Distribution Liability:
  Data are subject to the GeoBase Unrestricted Use Licence Agreement (http://www.geobase.ca - in the Data section).

Standard Order Process:
  Digital Form:
    Digital Transfer Information:
      Format Name:
        CDED ASCII
      File Decompression Technique:
        WinZip compression software
    Digital Transfer Option:
      Online Option:
        Computer Contact Information:
          Network Address:
            Network Resource Name:
              FTP site
  Fees:
    Free

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## Metadata Reference Information

Metadata Date:
  2007-07-04

Metadata Contact:
  Contact Information:
    Contact Organization Primary:
      Contact Organization:
        Government of Canada, Natural Resources Canada, Centre for Topographic Information
      Contact Person:
        GeoBase Technical Support
    Contact Address:
      Address Type:
        mailing and physical
      Address:
        2144, King Street West, Suite 010
      City:
        Sherbrooke
      State or Province:
        Quebec
      Postal Code:
        J1J 2E8
      Country:
        Canada
    Contact Voice Telephone:
      +01-819-564-4857 / 1-800-661-2638 (Canada and USA)
    Contact Facsimile Telephone:
      +01-819-564-5698
    Contact Electronic Mail Address:
      SupportGeoBase@NRCan.gc.ca
    Hours of Service:
      8:30 to 12:00 and 13:00 to 16:30 EST

Metadata Standard Name:
  FGDC Content Standard for Digital Geospatial Metadata

Metadata Standard Version:
  FGDC-STD-001-1998

Metadata Use Constraints:
  Only the English XML metadata file is valid according to the XML (W3C) schema as defined by the Federal Geographic Data Committee (FGDC) (http://www.fgdc.gov). The French version of the XML metadata file does not respect the domain of values, which is only available in English in certain fields, and exists solely for the presentation of information.
  Users must ensure that they use the FGDC XML schema with the English version of the XML metadata to validate the metadata.