Resource Specific Usage

Capturing information from users about how they are using data and limitations that they identify with specific products is an important part of the on-going process of documenting information quality. The ISO metadata standards (19115 and 19115-1) both include standard mechanisms for representing this kind of information. This page focuses on 19115-1 which includes and extends the 19115 approach.

Conceptual Model

MD_Usage Object

This Figure shows the MD_Usage object with the properties included in 19115 in black and those from 19115-1 in red. This object is used to record what (specificUsage) a person (userContactInfo) did with a dataset at a particular time (usageDateTime) and any limitations (userDeterminedLimitations) they identified. The data provider can respond (response) and provide more information (additionalDocumentation) as well as a citation to information about known issues with the data (identifiedIssues).

Example: MODIS Atmosphere Validation

The MODIS Atmosphere Team has identified issues with a number of products and shares information about those issues with users. This web page serves the need addressed by MD_Usage very well, and, more importantly, it serves a critical need for MODIS users.

The page includes descriptions of several limitations occurring at different times and identified by different users. The ISO 19115-3 XML representation for the first two looks like:

<mri:resourceSpecificUsage>
  <mri:MD_Usage>
    <mri:specificUsage>
      <gco:CharacterString>Aerosol Product (04_L2) Problematic: [PGE = PGE04 v5.3.7] [Period = 8/2002-10/2007] [Platform = Aqua] </gco:CharacterString>
    </mri:specificUsage>
    <mri:userDeterminedLimitations>
      <gco:CharacterString>Uninitialized, Non-Fill Data Occasionally Contaminates Deep Blue Aerosol parameters. In certain circumstances, data with very high solar zenith angles (SZA) can cause uninitialized, non-fill data to be placed into the MYD04_L2 file. Fill data is appropriate for Deep Blue retrieval at very high SZA (above 72 degrees). The latest version of Deep Blue corrects this defect. To date, a limited number of days which are effected by this problem were found. Problematic data is typically found in the November to March time period, and in polar regions (Canada, Siberia, Alaska, Greenland, Antarctica) In any given month, there may be a single day exhibiting the problem, or there may be a large number of days.</gco:CharacterString>
    </mri:userDeterminedLimitations>
    <mri:userContactInfo>
      <cit:CI_Responsibility>
        <cit:role>
          <cit:CI_RoleCode codeList="codeListLocation#CI_RoleCode" codeListValue="pointOfContact">pointOfContact</cit:CI_RoleCode>
        </cit:role>
        <cit:party>
          <cit:CI_Organisation>
            <cit:name>
              <gco:CharacterString>NASA/GSFC > Goddard Space Flight Center, NASA</gco:CharacterString>
            </cit:name>
            <cit:individual>
              <cit:CI_Individual>
                <cit:name>
                  <gco:CharacterString>Jeremy Warner</gco:CharacterString>
                </cit:name>
              </cit:CI_Individual>
            </cit:individual>
          </cit:CI_Organisation>
        </cit:party>
      </cit:CI_Responsibility>
    </mri:userContactInfo>
    <mri:response>
      <gco:CharacterString>Corrected: [PGE = PGE04 v5.3.8] [Period = 10/2007-current] [Platform = Aqua]</gco:CharacterString>
    </mri:response>
    <mri:identifiedIssues>
      <cit:CI_Citation>
        <cit:title>
          <gco:CharacterString>MODIS Atmosphere Validation: Data Issues (known problems)</gco:CharacterString>
        </cit:title>
        <cit:onlineResource>
          <cit:CI_OnlineResource>
            <cit:linkage>
              <gco:CharacterString>http://modis-atmos.gsfc.nasa.gov/validation.html</gco:CharacterString>
            </cit:linkage>
          </cit:CI_OnlineResource>
        </cit:onlineResource>
      </cit:CI_Citation>
    </mri:identifiedIssues>
  </mri:MD_Usage>
</mri:resourceSpecificUsage>
<mri:resourceSpecificUsage>
  <mri:MD_Usage>
    <mri:specificUsage>
      <gco:CharacterString>Water Vapor Product (05_L2) Problematic: [PGE = PGE05 all] [Period = 2/2000-current] [Platform = Terra, Aqua] </gco:CharacterString>
    </mri:specificUsage>
    <mri:userDeterminedLimitations>
      <gco:CharacterString>Near-IR Water Vapor Problematic over Bright Clouds. The near-IR water vapor values over some very bright cloud pixels are in error because the channels used in the retrieval algorithm are saturated over bright clouds. In order to fix the problem, QA parameters need to be utilized so that saturated pixels are properly identified and flagged. </gco:CharacterString>
    </mri:userDeterminedLimitations>
    <mri:userContactInfo>
      <cit:CI_Responsibility>
        <cit:role>
          <cit:CI_RoleCode codeList="codeListLocation#CI_RoleCode" codeListValue="pointOfContact">pointOfContact</cit:CI_RoleCode>
        </cit:role>
        <cit:party>
          <cit:CI_Organisation>
            <cit:name>
              <gco:CharacterString>DOD/USNAVY/NRL > Naval Research Laboratory, U.S. Navy, U. S. Department of Defense</gco:CharacterString>
            </cit:name>
            <cit:individual>
              <cit:CI_Individual>
                <cit:name>
                  <gco:CharacterString>Dr. Bo-Cai Gao</gco:CharacterString>
                </cit:name>
              </cit:CI_Individual>
            </cit:individual>
          </cit:CI_Organisation>
        </cit:party>
      </cit:CI_Responsibility>
    </mri:userContactInfo>
    <mri:response>
      <gco:CharacterString>Corrected: [T.B.D.]</gco:CharacterString>
    </mri:response>
    <mri:identifiedIssues>
      <cit:CI_Citation>
        <cit:title>
          <gco:CharacterString>MODIS Atmosphere Validation: Data Issues (known problems)</gco:CharacterString>
        </cit:title>
        <cit:onlineResource>
          <cit:CI_OnlineResource>
            <cit:linkage>
              <gco:CharacterString>http://modis-atmos.gsfc.nasa.gov/validation.html</gco:CharacterString>
            </cit:linkage>
          </cit:CI_OnlineResource>
        </cit:onlineResource>
      </cit:CI_Citation>
    </mri:identifiedIssues>
  </mri:MD_Usage>
</mri:resourceSpecificUsage>