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Element Description

The Grid Mapping Names element identifies the grid scheme the data are originally distributed in (if the data is gridded).

Best Practices

Some Earth Observation (EO) data are distributed in a gridded format, which means that the data is organized into pre-defined, regularly spaced 2D or 3D areas. For EO data, each grid cell is usually associated with an area of coverage of the Earth's surface, making grids useful for purposes of locating data and data interoperability. Outputs of numerical models and analyses of observational data are some examples of data that might be gridded. Grid schemes are defined by various parameters such as the size of the grid cells, number of grid cells present, and the corresponding location to the Earth's surface. Some grid schemes have names; however, this field can also be leveraged to provide a brief explanation/ specification of the grid the data is provided in if the grid scheme does not have an official name. Bear in mind that the grid name provided in this element must match a grid that has been defined in the parent collection. Providing a grid name is optional and can be repeated if the data are distributed in multiple grid formats. There is no controlled vocabulary for this field, so it is advised that a consistent grid naming convention be adopted for all metadata records coming from the same data provider.

Examples:

GridMappingNames: "MODIS Sinusoidal Tile Grid", "Lambert Azimuthal Equal-Area"

GridMappingNames: "0.25 - degree latitude x 0.25 - degree longitude US grid (300x120)"

Element Specification

Grid Mapping Names is optional in UMM-G, multiple grid names may be provided (Cardinality: 0..*)

Model

Element

Type

Constraints

Required?

Cardinality

UMM-G

GridMappingNames

Array composed of:

Strings

1 - 1024 characters

No

0..*

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).

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Please see the expandable sections below for flowchart details.

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ARC Priority Matrix

Priority Categorization	Justification
Red = High Priority Finding	Not Applicable
Yellow = Medium Priority Finding	This element is categorized as medium priority when: Evidence suggests the Grid Mapping Name is inaccurate for the granule.
Blue = Low Priority Finding	This element is categorized as low priority when: The grid naming convention is not consistent between metadata records from the same provider.
Green = No Findings/Issues	The element is provided and follows all applicable criteria specified in the best practices section above.

ARC Automated Checks

ARC uses the pyQuARC library for automated metadata checks. Please see the pyQuARC GitHub for more information.

Dialect Mappings

ECHO 10

The Grid Mapping Names element does not currently map to ECHO 10.

UMM-G Element	ECHO 10 Path	Type	Constraints	Required in ECHO10?	Cardinality
GridMappingNames	N/A	N/A	N/A	N/A	N/A

Example Mapping

ECHO 10

N/A

UMM

"GridMappingNames": ["Equal-Area Scalable Earth Grid (EASE-Grid)", "5.0 degree latitude x 5.0 degree longitude global grid (36x72)"],

ISO 19115-2 MENDS

The Grid Mapping Names element is not required for ISO 19115-2 MENDS (Cardinality: 0..1).

UMM-G Element

ISO Path

Type

Notes

GridMappingNames

/gmi:MI_Metadata/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:extent/gmd:EX_Extent [=>

with

gmd:EX_Extent attribute id="boundingExtent" (this element is included with the spatial extent block - a new 'geographicElement' path should be provided for each grid mapping name)

[=>/gmd:geographicElement/gmd:EX_GeographicDescription id="GridMappingName*"/gmd:geographicIdentifier/gmd:MD_Identifier/gmd:code/gco:CharacterString = {grid mapping name}

where * = 1, 2, etc. A unique number for each grid mapping name.

[=>/gmd:geographicElement/gmd:EX_GeographicDescription/gmd:geographicIdentifier/gmd:MD_Identifier/gmd:codeSpace/gco:CharacterString = gov.nasa.esdis.umm.gridmappingname
[=>/gmd:geographicElement/gmd:EX_GeographicDescription/gmd:geographicIdentifier/gmd:MD_Identifier/gmd:description/gco:CharacterString = GridMappingName

String

This element maps to the UMM-G Element Grid Mapping Names.

Note that this element is included with the spatial extent block , therefore; a new 'geographicElement' needs to be added for each grid mapping name. The geographicElement includes the boundingBox id.

Example Mapping

ISO 19115-2 MENDS

<gmi:MI_Metadata>
  <gmd:identificationInfo>
    <gmd:MD_DataIdentification>
      <gmd:extent>
        <gmd:EX_Extent id="boundingExtent">
          <gmd:geographicElement>
            <gmd:EX_GeographicDescription id="GridMappingName1">
              <gmd:geographicIdentifier>
                <gmd:MD_Identifier>
                  <gmd:code>
                    <gco:CharacterString>Equal-Area Scalable Earth Grid (EASE-Grid)</gco:CharacterString>
                  </gmd:code>
                  <gmd:codespace>
                    <gco:CharacterString>gov.nasa.esdis.umm.gridmappingname</gco:CharacterString>
                  </gmd:codespace>
                  </gmd:description>
                    <gco:CharacterString>GridMappingName</gco:CharacterString>
                  </gmd:description>
                </gmd:MD_Identifier>
              </gmd:geographicIdentifier>
            </gmd:EX_GeographicDescription>
          </gmd:geographicElement>
          <gmd:geographicElement>
            <gmd:EX_GeographicDescription id="GridMappingName2">
              <gmd:geographicIdentifier>
                <gmd:MD_Identifier>
                  <gmd:code>
                    <gco:CharacterString>5.0 degree latitude x 5.0 degree longitude global grid (36x72)</gco:CharacterString>
                  </gmd:code>
                  <gmd:codespace>
                    <gco:CharacterString>gov.nasa.esdis.umm.gridmappingname</gco:CharacterString>
                  </gmd:codespace>
                  </gmd:description>
                    <gco:CharacterString>GridMappingName</gco:CharacterString>
                  </gmd:description>
                </gmd:MD_Identifier>
              </gmd:geographicIdentifier>
            </gmd:EX_GeographicDescription>
          </gmd:geographicElement>
        </gmd:EX_Extent>
      </gmd:extent>
    </gmd:MD_DataIdentification>
  </gmd:identificationInfo>
</gmi:MI_Metadata>

UMM

"GridMappingNames": ["Equal-Area Scalable Earth Grid (EASE-Grid)", "5.0 degree latitude x 5.0 degree longitude global grid (36x72)"],

ISO 19115-2 SMAP

The Grid Mapping Names element currently does not map to ISO 19115-2 SMAP.

UMM-G Element	ISO Path	Type	Notes
GridMappingNames	N/A	N/A	N/A

Example Mapping

ISO 19115-2 SMAP

N/A

UMM

"GridMappingNames": ["Equal-Area Scalable Earth Grid (EASE-Grid)", "5.0 degree latitude x 5.0 degree longitude global grid (36x72)"],

UMM Migration

UMM Version 1.4.0	Translation Direction	UMM Version 1.5.0

History

UMM Versioning

Version	Date	What Changed
1.6.0	11/4/2019	No changes were made for Grid Mapping Names during the transition from version 1.5.0 to 1.6.0.
1.5.0	01/30/2019	No changes were made for Grid Mapping Names during the transition from version 1.4.0 to 1.5.0.
1.4.0	08/01/2018

ARC Documentation

Version	Date	What Changed	Author
1.0	04/12/2019	Recommendations/priority matrix transferred from internal ARC documentation to wiki space	Camille Woods Jeanne' le Roux