HDF is the format of NASA EOS standard products. Since launch of the TERRA mission in 1999, the EOSDIS as accumulated over 3 petabytes of data and derived products containing geophysical parameters with an accumulation rate of over 3.5 terabytes per day. The vast majority of these products are stored natively using the Hierarchical Data Format (HDF) This presentation will give an overview of the range of EOS data products and the systems available to facilitate access by science and application users.

1. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
HDF, EOSDIS, NASA ESE Data Standards
Richard Ullman

2. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
Agenda
• ESDIS Status wrt HDF
• EOSDIS (American Customer Satisfaction Index)
• NASA Earth Science Standards Endorsement Process

3. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
ESDIS Status
•
Launch of Aura (July 25) marks end of development phase of the
EOSDIS Core System (ECS).
• System is now in maintenance. Capability refinements are under the
“Synergy” program.
– Data enters are now running “Synergy 3” release. Will be transitioning
to “Synergy 4” over the next six months.
•
Maintenance of HDF for EOS includes two components
– Support of NCSA’s HDF group through a cooperative agreement.
– Support of HDF-EOS through ECS maintenance contract
•
Other ESDIS project sponsored HDF-related work will be phased out
near the end of calendar year 2004.
– http://hdfeos.gsfc.nasa.gov website updates
– “SESDA” hdf data usability task
– Coordination, outreach and test bed development for HDF integration
through CEOS, OGC, ISO organizations.

4. NATIONAL AERONAUTICS
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HDF-EOS
•
A profile, convention, convenience API, etc for NASA’s Earth
Observation System standard data products.
– Defines structures for Point, Swath, Grid (Atmospheric Profile, Zonal
Table)
– Defines specific location for product metadata
• ODL encoded metadata compliant with FGDC content standards.
•
Maintained by a by L3-Communications under subcontract to
Raytheon’s ECS Maintenance and Development contract.
• Next release expected Dec. 2004
–
–
–
–
–
HDF5-1.6.3
SZIP 1.2
New inquiry functions
CEA (Cylindrical Equal Area grid projection
Improved performance in read/write functions

5. HDF in NASA Earth Remote
Sensing
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• HDF-EOS is format for EOS Standard Products
–
–
–
–
–
Landsat 7 (ETM+)
Terra (CERES, MISR, MODIS, ASTER, MOPITT)
Meteor-3M (SAGE III)
Aqua (AIRS, AMSU-A, AMSR-E, CERES, MODIS)
Aura(MLS, TES, HIRDLS, OMI
• HDF is used by other EOS missions
–
–
–
–
–
–
OrbView 2 (SeaWIFS)
TRMM (CERES, VIRS, TMI, PR)
Quickscat (SeaWinds)
EO-1 (Hyperion, ALI)
ICESat (GLAS)
Calypso
• Over 3 petabytes of EOSDIS archived data

6. NATIONAL AERONAUTICS
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HDF-EOS Lessons
• Definition of a set of data structures as a profile is not
sufficient to guarantee interoperability.
– Also need definition of content, especially metadata - this is
increasingly difficult the wider the disciplines covered.
– See AURA DSWG standards and NetCDF CF as examples.
– Also need conformance measures - no spec is so clear that it
cannot be misinterpreted.
• Even during life of mission, there must be allowance for
technology refresh.
– Technology advances affect user expectations.
– Well understood concept for hardware - traditionally less
recognized for science software and data products.
– See OAIS

7. NATIONAL AERONAUTICS
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Discussion topics today
• Ask the experts
– A growing number of software products depend upon the HDF
libraries. Are there suggestions for how to better coordinate
HDF library releases.
– Questions from participants.
• HDF-GEO?
– Last workshop there was strong opinion expressed that there
should be some kind of bridge among HDF geographic and
geophysical profiles.
• Can we develop a better sense of what such and “HDF-GEO” might
be?
• Is this the list? HDF-EOS, NetCDF API, HDF-NPOESS
• What are reasonable expectations for this effort?

8. NATIONAL AERONAUTICS
From
AND SPACE ADMINISTRATION
ESDSWG meeting last week:
Why Use a Standard?
•
•
•
•
Good documentation
Other projects have reviewed it and found it useful
Reusable software sometimes available
Potential users can see that standard and software
works
• Not management pressure or peer pressure – just more
practical

9. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
2004 EOSDIS Satisfaction Survey

10. NATIONAL AERONAUTICS
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2004 EOSDIS Satisfaction Survey
• A measure of customer satisfaction
– ESISS and ESSAAC have recommended that NASA focus on
measuring the “impact” of our systems and services rather than
just the “output”
• In 2004, NASA used a comprehensive survey to
determine the American Customer Satisfaction Index
(ACSI) for EOSDIS products and services.
– ACSI provides a normalized measure of customer satisfaction
that allows benchmarking against similar companies and
industries.
• 2004 survey results show that customer satisfaction with
EOSDIS compares very favorably with both industry and
other government agencies.

11. Snapshot of the American
NATIONAL AERONAUTICS
Customer Satisfaction Index
AND SPACE ADMINISTRATION
(ACSI)
• The # 1 national indicator of customer satisfaction today
• Compiled by the National Quality Research Institute at
the University of Michigan using methodology licensed
from the Claes Fornell International (CFI) Group
• Measures 40 industries and 200 organizations covering
75% of the U.S. Economy
– Over 70 U.S. Federal Government agencies have used ACSI to
measure more than 120 programs/services
• CFI’s Advanced methodology quantifiably measures and
links satisfaction levels to performance and prioritizes
actions for improvement

12. NATIONAL AERONAUTICS
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Survey Background
• EOSDIS survey was performed by CFI Group through a
contract with the Federal Consulting Group (Department
of Treasury).
• Survey questions developed by the DAAC User Services
Working Group were tailored to fit the CFI methodology
• ESDIS provided the CFI Group with 33,251 email
addresses from users who had used NASA/EOSDIS
products
– CFI sent invitations to participate in an online survey to 9,999
randomly selected users
• 1,056 responses were completed
• 1,016 surveys were used in the analysis (250 responses were
needed for statistically meaningful response).

13. NATIONAL AERONAUTICS
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EOSDIS Results
•
The Customer Satisfaction Index for NASA EOSDIS is…
75*
NASA EOSDIS Aggregate Segment
•
The Customer Satisfaction Index score is derived from customer responses
to three questions in the survey:
– How satisfied are you overall with the products and services provided by the
Data Center (79)?
– To what extent have the data, products and services provided by the Data Center
fallen short of or exceeded your expectations (73)?
– How well does the Data Center compare with an ideal provider of scientific data,
products and services (71)?
•
This score is four points higher than the 2003 American Customer
Satisfaction Index for the Federal Government overall (71).
* The confidence interval for ACSI is +/-1.1 for the aggregate at the 95% confidence level.

14. Score Comparison
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AND SPACE ADMINISTRATION
Current Location
74
ACSI
76
88
Customer Support
82
85
Delivery
83
72
Product Selection
and Order
73
69
Product Search
71
67
Product Quality
Complaints
69
34%
31%
USA
(n=478)
Outside
the USA
(n=577)

15. Customer Support -
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AND SPACE ADMINISTRATION
Score 84, Impact:
1.0
Customer Support
84
Professionalism
87
Technical knowledge
85
Accuracy of information provided
85
Helpfulness in selecting/finding data or
products
Helpfulness in correcting a problem
Timeliness of response
84
83
82
CFI considers
EOSDIS to be
“World Class” in
the area of
customer support.

16. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
Product Quality -
Product Quality
68
Score 68, Impact: 0.9
In what format were data or
products provided?
HDF-EOS 49%
HDF
NetCDF
39%
5%
Binary
Clarity of data
product
documentation
Thoroughness of
data product
documentation
69
14%
ASCII
12%
GeoTIFF
Ease of using the
data product in the
delivered format
19%
Other
7%
67
Was documentation…
Delivered with the data
68
44%
Pointed to (on a website) 41%
Not available
15%

17. NATIONAL AERONAUTICS
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Analysis of Results
•
Product quality is the lowest scoring component (68), and has a
relatively high impact (0.9).
– All attributes in this area received similar ratings
•
At 84 customer support scores well, and is also high impact (1.0).
– There is a significant difference in customer support ratings given by
customers within the U.S. (88) compared to those outside the U.S. (82).
•
The components product search, product selection and order are
highly correlated.
• Recent customers are more satisfied, but are also reporting more
problems.
• Percentage of customer complaints is fairly high (32%) when
compared to the federal government overall (12%).
– Customers may not be calling to complain about a problem, but rather to
seek assistance in solving the problem.
– 90% of respondents who answered the customer complaint questions
gave user services’ complaint handling a rating of “6” or above.

18. CFI’s Recommendations for
Improving ACSI
NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
• Focus on Product Quality:
– Review the type of data product documentation available with
each product. Work to improve the clarity and thoroughness of
the documentation.
– Assess the various data formats and work to improve the
usability of each.
– Offer a wider variety of data formats.
• Review the Product Search and Product Selection and
Order scores to determine how best to help customers
find the data they need:
– Due to high correlation, improvements in one area will likely
result in improvements in the other.
– Simplify the search process; make data products more apparent.
– Improve data product descriptions.

19. Product Format Ease of Use
Comparison
NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
HDFEOS
HDF
GeoTIFF
Binary
ASCII
Valid Responses
270
190
61
53
44
Mean Valid Score
6.76
7.20
7.48
7.02
7.30
Median Valid Score
7
8
8
7
8
Standard Deviation
2.47
2.34
2.03
2.76
2.54
95% Confidence Interval
0.29
0.33
0.51
0.74
0.75
46.7%
52.6%
55.8%
49.0%
63.7%
% of Users Assigning 8 or More
The relatively low scoring of HDF-EOS was supported by users’ free
text comments.

20. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
NASA’s Earth Science Data Systems
Standards Process

21. NATIONAL AERONAUTICS
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Insights
• Interoperability does not require homogeneous systems,
but rather coordination at the interfaces.
• Management can judge success based upon program
goals rather than dictate solutions.
– example: degree of interoperability rather than use of particular
data format.
• Communities of practice have solutions.
• Published practices that demonstrate benefit can grow
…
– successful practice in specific community
– broader community adoption
– community-recognized “standards”

22. NATIONAL AERONAUTICS
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The ESDSWG Standards Process
• Modeled on Internet Engineering Task Force “RFC”
process and tailored to meet NASA’s circumstances. The
standards process provides:
– Registers community practice for NASA
• NASA Earth science data management can rely on standards to
achieve highest priority interoperability
– Encourages consensus within communities
• Science investigators are assured that standards contribute to
science success in their discipline.
– Grows use of common practices among related activities
• Discipline communities benefit from the expertise gained by others
– Documents data systems practices for use by external
communities.
• Lowers barriers to entry and use of NASA data.

23. Standards Process Group
Strategy
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•
Adopt standards at the interfaces, appropriate to given science and
drawn from successful practice.
–
–
–
–
Find specifications with a potentially wide appeal
Draw attention to a much broader audience
Monitor use, promote what works well
Result : Accelerate the evolution and adoption
•
•
Preferred source of RFC is community nomination.
Possible to direct creation of RFC in response to identified needs.
•
Consequence of endorsement
– Future NASA data systems component proposals will be judged partly
on how well they interoperate using community-identified practices or
else justify why departure from community has greater benefit.

24. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
Three Step Standards Process
Initial Screening
RFC
Community Core
Initial review of the RFC
Provide RFC submission support
Form TWG; set schedule
Review of Implementation
Proposed STD
Community Core
Community review and input
Evaluation and recommendation
Draft STD
Community Core
Review of Operation
Community review and input
Evaluation and recommendation
STD
Community Core

25. NATIONAL AERONAUTICS
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SPG Review
Stakeholde
rs
Evaluate
Implementations
TWG
Evaluate
Implementations and
Community Response
SPG Review and
Recommendation
SPG
Recommendation

26. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
What’s in the works
• DAP 2 standard – used by many in the oceanographic
community – basis for the DODS and OpenDAP servers.
-- submitted in June as a “Community Standard”
– “Request For Comments” on implementation experience
distributed October 1, comments due November 12.
• Precipitation Community – discussing potential science
content standards being used to define level 2 & level 3
data
– Self identified group of precipitation scientists have identified
need and are proposing a draft. Are discussing at IPWG in
Monterey.
– “The community is establishing de facto standards in this area
and that is the best way to deal with this.”
• FGDC Vegetation Index standard – discussing with
potential community members

27. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
Ideas from the last ES-DSWG
•
•
•
•
GCMD DIF
GeoTIFF
NetCDF CF
OGC suite

28. NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
Community Leadership
• Strong proposals will have:
–
–
–
–
–
Leadership to support and use standard
Potential for impact
Potential for approval
Simple standard is better
Potential for spillover to other communities
• Successful RFCs will have:
–
–
–
–
At least two implementers
Demonstrated operational benefit
Leadership in generating the RFC
Community willing/able to review

29. NATIONAL AERONAUTICS
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SPG Contacts
• Earth Science Data Systems Standards Process Group
– http://spg.gsfc.nasa.gov/spg
• Chairs SPG
– Richard Ullman richard.ullman@nasa.gov
– Ming-Hsiang Tsou mtsou@mail.sdsu.edu