Lessons Learned in Generating Crosswalks for Earth Science Metadata

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Lessons Learned in Generating Crosswalks for
Earth Science Metadata
http//hdfeos.gsfc.nasa.gov/datamapping/index.cfm
Lori J. Tyahla Weijun Su Global Science
Technology, Inc. Richard Ullman NASA, Goddard
Space Flight Center
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Overview

• The Goal Interoperability among data systems
• The Challenge Automated translation of metadata
• The Method Develop and maintain crosswalks for
  translation
• The Lessons
• Definitions need to be complete, unambiguous,
  further clarified using examples, and written for
  a wider audience.
• Automated mapping of a generalized attribute in
  one system or standard to more specific
  attributes in another is not straightforward.
• Ongoing, diligent human input is required.

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Systems and Standards

• The Systems
• Earth Observing System Data and Information
  System (EOSDIS) Core System (ECS)
• Earth Observing System (EOS) Clearing House
  (ECHO)
• Global Change Master Directory (GCMD)

• The Standards
• Content Standard for Digital Geospatial Metadata,
  Federal Geographic Data Committee
  (FGDC-STD-001-1998)
• Content Standard for Digital Geospatial Metadata
  Extensions for Remote Sensing Data, Federal
  Geographic Data Committee (FGDC-STD-012-2002)

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Steps Toward Reaching Goal

• Write documentation with a wider audience in
  mind. Provide clear, complete definitions
  supported by examples for all classes and
  attributes.
• Use valids to help constrain the problem of
  mapping generalized attributes on one system to
  specific ones in another system.
• Designate one person only to develop the
  crosswalk if possible to reduce mapping
  inconsistency due to the subjectivity of the
  human element.