Download The Disappearing Data Problem

The Disappearing Data
Problem
Steve Morris
Head of Digital Library Initiatives
North Carolina State University
Libraries
Problem: Preserving Digital Geospatial Data
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Industry focus on access to most current data
“Kill and fill” as common data management practice
Complex, multi-file/multi-format objects – hard to preserve
Shift to web services-based consumption – who builds the
archive?
Are we in the middle of
a “Digital Dark Age”?
Future uses of data are difficult to
anticipate, as with circa 1900
Sanborn Maps.
Temporal Data Supports Business Needs
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Land use change analysis
Real estate trends analysis
Site selection (past uses?)
Economic planning
What should the data
snapshot frequency be?
Parcel Boundary Changes 2001-2004
North Raleigh, NC
Challenges: Complex Data Representations
• Maps and spatial documents are more then the sum of the
underlying datasets
• End products are combinations of datasets + application of
symbology, classification, annotation, data models, etc. –
difficult to preserve
The true counterpart to
the old map is not
the geospatial dataset
but rather the geospatial
project
Challenges: Geospatial Web Services
• Large volumes of data and rapid pace of update make
web services or API access attractive
• Data increasingly ephemeral
• OGC Web Map Context spec allows saving of application
state … but not data state
How does one document
decisions based on interactions
with constantly changing
web services?
Mashups, Web 2.0, etc.: New Opportunities
• Example: Web mashup interactions with existing systems
spur creation of intermediate content layers: e.g., tiling and
caching of WMS services
• Identification of a standard tiling scheme may create a
new preservation opportunity (temporal axis on caches?)
Getting Started with “Geoarchiving”
• Library of Congress: National Digital Information
Infrastructure and Preservation Program (NDIIPP) –
addressing various digital content types
• North Carolina Geospatial Data Archiving Project
(NCGDAP) – one of 8 initial NDIIPP partnerships
• … in partnership with NC OneMap which provides
seamless access to state/local/federal data
How do we support “permanent access” – not just
“bit preservation”?
Cultivating a market
for older data.
Current access to
and use of data
improves likelihood
of longer-term
preservation
Questions?
Contact:
Steve Morris
Head, Digital Library Initiatives
NCSU Libraries
[email protected]
NCGDAP:
http://www.lib.ncsu.edu/ncgdap
NDIIPP:
http://www.digitalpreservation.gov/
NC OneMap: http://www.nconemap.net/