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Element Description

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The Spatial Representation Information element...Information element stores information about the reference frame from which horizontal and vertical spatial domains are measured. The horizontal reference frame includes fields for Geodetic Model, Geographic Coordinates, and Local Coordinates. The Vertical reference frame includes fields for altitudes (elevations) and depths.

Best Practices

Providing Spatial Information is optional, but encouraged. This element can be used to provide horizontal and/or vertical coordinate system information. 

The Spatial Coverage Type field is required for Spatial Information. 

Spatial Coverage Type: Denotes the type of spatial coverage of the collection. While this field is not currently controlled, recommend providing one of the spatial coverage type enumeration values: EARTH/GLOBAL, HORIZONTAL, VERTICAL, ORBITAL, HORIZONTAL_VERTICAL, ORBITAL_VERTICAL, HORIZONTAL_ORBITAL, HORIZONTAL_VERTICAL_ORBITAL, LUNAR

Vertical Spatial Information

The following sub-elements can be used to describe Vertical Coordinate Systems.

There are 2 categories for Vertical Coordinate Systems including:

(1) Altitude System Definition 

Altitude System Definition should be used to describe data with a vertical component that is above-ground. Sub-elements under Altitude System Definition are summarized below:

• • • Datum Name: The name of the vertical datum the data is encoded in. Vertical datums define a level reference surface from which vertical measurements are compared. There are many standard vertical datums. If a standard vertical datum is used, it is recommended that the EPSG vertical datum name be provided. 
    • Distance Units: The units in which altitude measurements are recorded. This field is controlled and must be selected from one of the following values: HectoPascals, Kilometers, Millibars
    • Resolutions: The minimum distance possible between two adjacent values, expressed in distance units of measure for the collection.
      

(2) Depth System Definition

Depth System Definition should be used to describe data with a vertical component that is below-ground. Sub-elements under Depth System Definition are summarized below:

• • • Datum Name: The name of the vertical datum the data is encoded in. Vertical datums define a level reference surface from which vertical measurements are compared. There are many standard vertical datums. If a standard vertical datum is used, it is recommended that the EPSG vertical datum name be provided.
      
    • Distance Units: The units in which depth measurements are recorded. This field is controlled and must be selected from one of the following values: Fathoms, Feet, HectoPascals, Meters, Millibars
    • Resolutions: The minimum distance possible between two adjacent values, expressed in distance units of measure for the collection.

Best Practices

There are eighteen sub-elements that comprise Spatial Representation Information:

        SpatialCoverageType: Denotes whether the spatial coverage of the collection is horizontal, vertical, horizontal and vertical, orbit, or vertical and orbit.

        VerticalCoordinate System/AltitudeSystemDefinition/DatumName: The identification given to the level surface taken as the surface of reference from which measurements are compared.

VerticalCoordinateSystem/AltitudeSystemDefinition/DistanceUnits: The units in which altitude measurements are recorded.

VerticalCoordinateSystem/AltitudeSystemDefinition/EncodingMethod: 

VerticalCoordinateSystem/AltitudeSystemDefinition/Resolutions: The minimum distance possible between two adjacent values, expressed in distance units of measure for the collection.

VerticalCoordinateSystem/DepthSystemDefinition/DatumName: The identification given to the level surface taken as the surface of reference from which measurements are compared.

VerticalCoordinateSystem/DepthSystemDefinition/DistanceUnits: The units in which measurements are recorded.

VerticalCoordinateSystem/DepthSystemDefinition/EncodingMethod:

VerticalCoordinateSystem/DepthSystemDefinition/Resolutions: The minimum distance possible between two adjacent values, expressed in distance units of measure for the collection.

HorizontalCoordinateSystem/GeodeticModel/HorizontalDatumName: The identification given to the reference system used for defining the coordinates of points.

HorizontalCoordinateSystem/GeodeticModel/EllipsoidName: Identification given to established representation of the Earth's shape. HorizontalCoordinateSystem/GeodeticModel/SemiMajorAxis: Radius of the equatorial axis of the ellipsoid.

HorizontalCoordinateSystem/GeodeticModel/DenominatorOfFlatteningRatio: The ratio of the Earth's major axis to the difference between the major and the minor.

HorizontalCoordinateSystem/GeographicCoordinateSystem/GeographicCoordinateUnits: Units of measure used for the geodetic latitude and longitude resolution values (e.g., decimal degrees).

HorizontalCoordinateSystem/GeographicCoordinateSystem/LatitudeResolution: The minimum difference between two adjacent latitude values in the Geographic Coordinate System,  expressed in Geographic Coordinate Units of measure, expressed as a two-digit decimal number, e.g., 0.01.

HorizontalCoordinateSystem/GeographicCoordinateSystem/LongitudeResolution: The minimum difference between two adjacent longitude values in the Geographic Coordinate System, expressed in Geographic Coordinate Units of measure, expressed as a two-digit decimal number, e.g., 0.01.

HorizontalCoordinateSystem/LocalCoordinateSystem/GeoReferenceInformation: The information provided to register the local system to the Earth (e.g. control points, satellite ephemeral data, and inertial navigation data).

HorizontalCoordinateSystem/LocalCoordinateSystem/Description: A description of the Local Coordinate System and geo-reference information.

          Examples:

           SpatialCoverageType: "Horizontal"

           VerticalCoordinateSystem/AltitudeSystemDefinition/DatumName: North American Vertical Datum of 1988

           VerticalCoordinateSystem/AltitudeSystemDefinition/DistanceUnits: "Kilometers"

           VerticalCoordinateSystem/AltitudeSystemDefinition/EncodingMethod: "Implicit coordinate"

           HorizontalCoordinateSystem/LocalCoordinateSystem/GeoReferenceInformation: "Control Points"

           VerticalCoordinateSystem/DepthSystemDefinition/DistanceUnits: "HectoPascals"

Metadata Validation and QA/QC

All metadata entering the CMR goes through the below process to ensure metadata quality requirements are met. All records undergo CMR validation before entering the system. The process of QA/QC is slightly different for NASA and non-NASA data providers. Non-NASA providers include interagency and international data providers and are referred to as the International Directory Network (IDN).

Please see the expandable sections below for flowchart details.

ARC Priority Matrix

This element is categorized as highest priority when:

• The information provided is not related to the element.
• The descriptions are inaccurate for the data set.

This element is categorized as medium priority when:

• The description is missing.

This element is categorized as low priority when:

• The descriptions includes spelling or grammatical errors.

ARC Automated Rules

Dialect Mappings

Metadata Validation and QA/QC

All metadata entering the CMR goes through the below process to ensure metadata quality requirements are met. All records undergo CMR validation before entering the system. The process of QA/QC is slightly different for NASA and non-NASA data providers. Non-NASA providers include interagency and international data providers and are referred to as the International Directory Network (IDN).

Please see the expandable sections below for flowchart details.

Dialect Mappings

String