The Disappearing Data Problem Steve Morris Head of Digital Library Initiatives North Carolina State University Libraries

Problem: Preserving Digital Geospatial Data 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 Land use change analysis Real estate trends analysis Site selection (past uses?) Economic planning Parcel Boundary Changes North Raleigh, NC What should the data snapshot frequency be?

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 NCGDAP: NDIIPP: NC OneMap: