The document discusses including ISO metadata standards in NASA Earth Science products in a consistent way across missions. It proposes representing ISO concepts and content in HDF files using standard XML representations. Specifically: 1) Identifying important ISO concepts and representing them in ISO 19139-2 XML for the SMAP mission. 2) Including the ISO XML as a string attribute in the Metadata group of SMAP granules to include the concepts. 3) Developing standard XSLT transforms to translate between ISO XML and NcML/HDF representations in a lossless way. This allows ISO metadata to be accessible and consistent across products and missions while using mission-specific HDF representations.

1. ISO Metadata and Granules
Ted Habermann, Director of Earth Science
The HDF Group
thabermann@hdfgroup.org
1

2. ISO Metadata Standards
ISO Standards come in two parts:
Concepts / Content Representations

3. The Goal
3
Include ISO concepts/content in [NASA]
Earth Science products in a
representation that is useful and
consistent across products and
missions.

4. SMAP Approach
Concepts / Content Representations
1) Identify ISO concepts important for SMAP users (ISO 19115-2).
2) Represent those concepts in standard XML (ISO 19139-2).

5. SMAP Granules Approach (1)
ISO XML
blob
included as
a string
attribute in
the
Metadata
group.
ISO 19139-2

6. SMAP Granules Approach (2)
As groups and attributes in Metadata Group.

7. Achieves the Goal?
7
The approach achieves the first part of the goal:
Include ISO concepts/content in NASA Earth Science
products
in a representation that is useful and consistent
across products and missions.
But… the representation is specific for the SMAP mission.

8. ISO Metadata as Information Hub
Citations are included in the ISO Metadata Standards as a way to reference resources
that provide details that are not included directly in the metadata.
Metadata
XML
dataset /
resource
source
keyword
thesaurus
& ontology
evaluation
procedure
standard
specification
algorithm associated
resource
application
schema
alternate
metadata
metadata
& service
standard
associated
resource
name/metadata
additional
documentation
constraints
reference
source
metadata
process
reference &
documentation
software
reference
feature
catalog
format
specification

9. ISO Dataset Titles
All ISO Citations include the concept of ”Title" which can be represented as a
CharacterString or a FileName. The ISO xPath to the dataset title is special.
/gmi:MI_Metadata
/gmd:identificationInfo/gmd:MD_DataIdentification
/gmd:citation/gmd:CI_Citation
/gmd:title/gco:CharacterString | gmx:FileName
I
S
O

10. SMAP Dataset Titles (1)
10

11. SMAP Dataset Titles (2)
11

12. Accessing Dataset Titles
We have the dataset titles in two locations: ISO and SMAP (HDF)
/gmi:MI_Metadata
/gmd:identificationInfo/gmd:MD_DataIdentification
/gmd:citation/gmd:CI_Citation
/gmd:title/gco:CharacterString | gmx:FileName
/Metadata/DatasetIdentification/fileName
This
mapping is
unique to
SMAP.
/gmi:MI_Metadata
/gmd:identificationInfo/gmd:MD_DataIdentification
/gmd:citation/gmd:CI_Citation
/gmd:title/gco:CharacterString | gmx:FileName
/Metadata
/DatasetIdentification
/fileName=/
I
S
O
S
M
A
P

13. Can HDF Paths = ISO Paths?
I
S
O
H
D
F

14. ISO: Roles and Types
Roles = lowerCamelCase / Types = AA_UpperCamelCase
ISO XML always alternates between roles and types.
Each hierarchy level is either a role level or a type level.
/gmi:MI_Metadata
/gmd:identificationInfo/gmd:MD_DataIdentification
/gmd:citation/gmd:CI_Citation
/gmd:title/gco:CharacterString | gmx:FileName

15. HDF: Groups and Attributes
HDF: Groups and Attributes
NcML: Groups and Attributes with XML attributes

16. The Goal
ISO Roles
and Types
NcML Groups
and Attributes
and XML
Attributes
Rules

17. The Workflow
17
SMAP
19115-2
(19139-2)
SMAP
19115-1
(19115-3)
SMAP
NcML
SMAP
19115-1
(19115-3)
Translation Proofing File Differencing
SMAP
HDF
Product
Designer
The method we use to develop and test this
approach involves several (standard) XSLT
transforms (solid arrows) and comparisons
between input metadata and metadata
transformed to NcML and back to ISO (grey
arrows). All of these transforms are lossless.

18. The Workflow
18
SMAP
19115-2
(19139-2)
SMAP
NcML
SMAP
19115-2
(19139-2)
File Differencing
The same transforms can be used to go
directly from ISO 19139-2 (the ISO version
currently used by NASA and NOAA) to NcML
and back.
SMAP
HDF
Product
Designer

19. ISO 19139-2 > NcML > HDF
19
/gmi:MI_Metadata
/gmd:identificationInfo/gmd:MD_DataIdentification
/gmd:citation/gmd:CI_Citation
/gmd:title/gco:CharacterString | gmx:FileName
/nc:netcdf
/nc:group[@name=“gmi:MI_Metadata]
/nc:group[@name=“gmd:identificationInfo]
/nc:group[@name=“gmd:citation]
/nc:group[@name=“gmd:title]
/nc:attribute[@name=“value”]/@value
I
S
O
N
C
M
L
/gmi:MI_Metadata/gmd:identificationInfo/gmd:citation/gmd:title/value
S
M
A
P

20. ISO 19115-3 > NcML > HDF
20
/nc:netcdf
/nc:group[@name=“mdb:MD_Metadata]
/nc:group[@name=“mdb:identificationInfo]
/nc:group[@name=“mri:citation]
/nc:group[@name=“mri:title]
/nc:attribute[@name=“value”]/@value
/mdb:MD_Metadata
/mdb:identificationInfo/mri:MD_DataIdentification
/mri:citation/cit:CI_Citation
/cit:title/gco:CharacterString | gcx:FileName
I
S
O
N
C
M
L
S
M
A
P
/mdb:MD_Metadata/mdb:identificationInfo/mri:citation/mri:title/value

21. ISO 19139-2 and 19115-3 = HDF
21
/gmi:MI_Metadata
/gmd:identificationInfo/gmd:MD_DataIdentification
/gmd:citation/gmd:CI_Citation
/gmd:title/gco:CharacterString | gmx:FileName
/gmi:MI_Metadata
/gmd:identificationInfo
/gmd:citation
/gmd:title
/value
/mdb:MD_Metadata
/mdb:identificationInfo/mri:MD_DataIdentification
/mri:citation/cit:CI_Citation
/cit:title/gco:CharacterString | gcx:FileName
/mdb:MD_Metadata
/mdb:identificationInfo
/mri:citation
/mri:title
/value
~
~
ISO 19115-2 HDF
ISO 19115-1 HDF
At least the transforms are consistent and the same!

22. What Does This Mean?
22
Any ISO conceptual model can be transformed into HDF and
extracted using standard transforms.

23. What Does This Mean?
1) We can write standard interoperable ISO metadata into
SWOT, NISAR, and PDS granules
2) They are all accessible with standard xPaths.
3) We can add standard ISO 19115 and 19115-1 groups to SMAP
without any impact on current metadata access.

24. The Goal
24
Include ISO concepts/content in NASA
Earth Science products in a
representation that is useful and
consistent across products and
missions.

25. Acknowledgements
25
This work was partially supported by contract number NNG10HP02C from NASA.
Any opinions, findings, conclusions, or recommendations expressed in this material are
those of the author and do not necessarily reflect the views of NASA or The HDF Group.