Lessons Learned in Generating Crosswalks for Earth Science

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 HDF/HDF-EOS Workshop VIII Aurora, CO, 10/27/2004

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. HDF/HDF-EOS Workshop VIII 2 Aurora, CO, 10/27/2004

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) HDF/HDF-EOS Workshop VIII 3 Aurora, CO, 10/27/2004

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. HDF/HDF-EOS Workshop VIII 4 Aurora, CO, 10/27/2004