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Explore the role of libraries in providing geospatial information services, including data collections, discovery tools, reference support, workshops, and map portals. Discover the potential of geospatial web services and the challenges of long-term preservation of digital geospatial data.
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Map Portals and Geoarchiving: New Opportunities in Geospatial Information ServicesSteve MorrisHead of Digital Library InitiativesNCSU Libraries GIS Technology: Sustaining the Future & Understanding the Past Case Western Reserve University October 13, 2005
Overview • Brief overview of library roles in digital geographic information services • Geospatial web services: opportunities and challenges for libraries • Long-term preservation of digital geospatial data Note: Percentages based on the actual number of respondents to each question
Library Geospatial Data Services: Data Collections • Acquire data (licensed and public domain) • License data for in-library or campus use • Provide networked access • Acquire or create value-added derivatives Note: Percentages based on the actual number of respondents to each question
Library Geospatial Data Services: Discovery Tools • Web documentation • Author and publish metadata • Searchable metadata catalogs • Integrate data into library catalog Note: Percentages based on the actual number of respondents to each question
Library Geospatial Data Services: Reference and Technical Support • Assistance with finding and selecting data • GIS “reference interview” • Line between reference support and technical support is extremely fuzzy • Support or administration of campus GIS software licenses • Reference support for locating software tools (e.g. scripts for ArcView and ArcGIS) Note: Percentages based on the actual number of respondents to each question
Library Geospatial Data Services: Workshops and Outreach • In-library workshops and class visits • Online workshops (Virtual Campus) • Marketing and Outreach • Work to engage broader number of academic departments in GIS activity • Work to lower barrier to entry in GIS work (access to software, data, training, support) • Library as ‘neutral ground’ well suited to coordinate with campus GIS infrastructure Note: Percentages based on the actual number of respondents to each question
Library Geospatial Data Services Timeline Map Collections Data Collections Map Servers Map Portals • Map Collections • Paper Maps • Data Collections • CD-ROMs, File server & FTP access • Map Servers • Integrate collected data, Web-based mapping • Map Portals • Integrate distributed, streaming data Note: Percentages based on the actual number of respondents to each question
NC Local Government Map Services Note: Percentages based on the actual number of respondents to each question
County Government Map Server Note: Percentages based on the actual number of respondents to each question
State Government Map Server Note: Percentages based on the actual number of respondents to each question
Federal Government Map Server Note: Percentages based on the actual number of respondents to each question
Open Geospatial Consortium(OGC) Technology Overview • The Open Geospatial Consortium (OGC) is a not-for-profit, international consortium: focus on data interoperability • Operates a Specification Development Program that is similar to other Industry consortia (W3C, etc.) • Also operates an Interoperability Program (IP), a partnership-driven engineering and testing program designed to deliver proven specifications into the Specification Development Program. • OGC used to talk about “web-enabling GIS”, now they talk about “geo-enabling the web.” Note: Percentages based on the actual number of respondents to each question
National Approaches • USGS National Map • Integrated WMS services • Services catalog • Geospatial One-Stop • Searchable services • Specialized Portals • FEMA Mapping • Katrina Portal • HUD E-Maps Note: Percentages based on the actual number of respondents to each question
State Approach: NC OneMap • Data integration through OGC specifications (currently just WMS) • Data sharing agreements • Metadata outreach • Ongoing data inventories • Practices and guidelines vis-à-vis map service configuration Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Geospatial Web Service Types • Image services • Deliver image resulting from query against underlying data • Limited opportunity for analysis • Feature services • Stream actual feature data, greater opportunity for data analysis • Other • Geocoding services • Routing • .etc. Note: Percentages based on the actual number of respondents to each question
Geospatial Web Services:Advantages • Time- and location-independent access • Access to extremely large datasets • Access to most current data • Ad hoc access to data for which there is typically low demand • Reduce barriers imposed by differences in formats, coordinate systems, etc. • Access to geoprocessing functionality Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Note: Percentages based on the actual number of respondents to each question
Geospatial Web Services: Shortcomings • Application performance will frequently not match that of locally loaded data • Up-time reliability issues • Many demonstration services, persistence is open to question • Dynamically changing content can lead to analysis surprises • Does not replace aesthetic value of paper map Note: Percentages based on the actual number of respondents to each question
Geospatial Web Services:When Most Useful? • User needs most current data • Data is subject to frequent change & update • User needs access to extremely large datasets • User wishes to preview data prior to use • User just needs background display • Need to integrate data into portable devices • Data not otherwise available Note: Percentages based on the actual number of respondents to each question
Geospatial Web Services: Integration Challenges for Libraries • Services difficult to discover and select from • In case of commercial services, campus licensing models not well evolved • Linking data objects with services that act upon them is not well supported by existing metadata and catalog schemes • Ambiguous rights issues • How to integrate into the physical browse environment of the map library? Note: Percentages based on the actual number of respondents to each question
Geospatial Web Services Rights IssuesExample: Desktop GIS-accessible ArcIMS • 39 of 100 NC counties have desktop GIS-accessible ArcIMS services • It is difficult to know how many of these counties actually expect users to either: • A) access data through desktop GIS for viewing only, or • B) extract and download data Note: Percentages based on the actual number of respondents to each question
Geospatial Data:Discovery and Selection Issues • Data extent • Thematic content & attributes • Currency • Format, coordinate system, datum, etc. • Licensing restrictions • Ease of access • Metadata availability • More … Note: Percentages based on the actual number of respondents to each question
Geospatial Web Services:Discovery and Selection Issues • Inherits many data selection issues such as coordinate system, etc. • Service type: image, feature, geocoding, … • Access protocol: OGC specs (WMS, WFS, WCS …), SOAP, ArcXML (ArcIMS image and feature services, specialized APIs (e.g. Google Maps) • Reliability, up-time performance, speed • Licensing scheme • Functions: annotation, saved maps, etc. • Image services: image formats Note: Percentages based on the actual number of respondents to each question
Facilitating Discovery of Services: Example: Directory of County Map Services Among top 15 most used resources on library web site 99.5% of directory users from outside ncsu.edu Note: Percentages based on the actual number of respondents to each question
Library Opportunities to Provide Geospatial Web Services • Publish WMS servers from public domain content not already available • Fill holes in service availability • Publish archival content • counter bias towards current content in the industry • Publish cascading map services • Create specialized front-ends to existing, distributed services Note: Percentages based on the actual number of respondents to each question
Cascading Map Services: Problems • Different versions of OGC standards • e.g., WMS 1.1.0, WMS 1.1.1 … • Differences in layer naming • ‘cadastral’ vs. ‘parcels’ vs. ‘property boundaries’ • Differences in classification schemes • e.g., inconsistent land use, zoning schemes • Service reliability, addressing stability, uptime • On top of standards & specifications, need community overlay of best practices Note: Percentages based on the actual number of respondents to each question
Community Practices in Cascading Map ServicesExample: Layer Names, Symbology, Classification Note: Percentages based on the actual number of respondents to each question
“Web mash-ups” and the New Mainstream Geospatial Web Services • New services such as Google Maps, MSN Virtual Earth, Yahoo Maps • Static, tiled images for efficient access • API’s for developer access • Positioning for mobile device-oriented application development • Engaging mainstream IT and general public • AJAX: Asynchronous Javascript and XML • New forms of map and service publishing Note: Percentages based on the actual number of respondents to each question
Integrating Traditional Geospatial Data and Services with New Services Note: Percentages based on the actual number of respondents to each question
Integrating Traditional Geospatial Data and Services with New Services But who preserves the data …? Note: Percentages based on the actual number of respondents to each question
Today’s geospatial data as tomorrow’s cultural heritage Note: Percentages based on the actual number of respondents to each question
Time series – vector data Parcel Boundary Changes 2001-2004, North Raleigh, NC Note: Percentages based on the actual number of respondents to each question
Time series – Ortho imagery Vicinity of Raleigh-Durham International Airport 1993-2002 Note: Percentages based on the actual number of respondents to each question
Risks to Digital Geospatial Data • Producer focus on current data • “Kill and fill”, absence of time-versioned content • Future support of data formats in question • Vast range of data formats in use--complex • Shift to “streaming data” for access • Archives have been a by-product of providing access • Preservation metadata requirements • Descriptive, administrative, technical, DRM • Geodatabases • Complex functionality Note: Percentages based on the actual number of respondents to each question
NC Geospatial Data Archiving Project (NCGDAP) • Partnership between university library (NCSU) and state agency (NCCGIA) • Focus on state and local geospatial content in North Carolina (statedemonstration) • Tied to NC OneMap initiative • Part of Library of Congress National Digital Information Infrastructure & Preservation Program (NDIIPP) • Objective: engage existing state/federal geospatial data infrastructures in preservation Note: Percentages based on the actual number of respondents to each question
NCGDAP Philosophy of Engagement Provide feedback to producer organizations/ inform state geospatial infrastructure Take the data as in the manner In which it can be obtained Wrangle and archive data Note the ‘Project’ in ‘North Carolina Geospatial Data Archiving Project’– the process, the learning experience, and the engagement with geospatial data infrastructures are more important than the archive Note: Percentages based on the actual number of respondents to each question
Earlier NCSU Acquisition Efforts • NCSU University Extension project 2000-2001 • Target: County/city data in eastern NC • “Digital rescue” not “digital preservation” • Hurricane Floyd flood response • Project learning outcomes • Confirmed concerns about long term access • Need for efficient inventory/acquisition • Wide range in rights/licensing • Need to work within statewide infrastructure Note: Percentages based on the actual number of respondents to each question
Big Geoarchiving Challenges • Format migration paths • Management of data versions over time • Preservation metadata • Harnessing geospatial web services • Preserving cartographic representation • Keeping content repository-agnostic • Preserving geodatabases • More … Note: Percentages based on the actual number of respondents to each question
Vector Data Format Issues • Vector data much more complicated than image data • ‘Archiving’ vs. ‘Permanent access’ • An ‘open’ pile of XML might make an archive, but if using it requires a team of programmers to do digital archaeology then it does not provide permanent access • Piles of XML need to be widely understood piles • GML: need widely accepted application schemas (like OSMM?) • The Geodatabase conundrum • Export feature classes, and lose topology, annotation, relationships, etc. • … or use the Geodatabase as the primary archival platform (some are now thinking this way) Note: Percentages based on the actual number of respondents to each question
Managing Time-versioned Content • Many local agency data layers continuously updated • E.g., some county cadastral data updated daily—older versions not generally available • Individual versioned datasets will wander off from the archive • How do users “get current metadata/DRM/object” from a versioned dataset found “in the wild”? • How do we certify concurrency and agreement between the metadata and the data? Note: Percentages based on the actual number of respondents to each question
Preservation Metadata Issues • FGDC Metadata • Many flavors, incoming metadata needs processing • Cross-walk elements to PREMIS, MODS? • Metadata wrapper • METS (Metadata Encoding and Transmission Standard) vs. other industry solutions • Need a geospatial industry solution for the ‘METS-like problem’ • GeoDRM a likely trigger—wrapper to enforce licensing (MPEG 21 references in OGIS Web Services 3) Note: Percentages based on the actual number of respondents to each question
Preserving Cartographic Representation • The true counterpart of the old map is not the GIS dataset, but rather the cartographic representation that builds on that data: • Intellectual choices about symbolization, layer combinations • Data models, analysis, annotations • Cartographic representation typically encoded in proprietary files (.avl, .lyr, .apr, .mxd) that do not lend themselves well to migration • Symbologies have meaning to particular communities at particular points in time, preserving information about symbol sets and their meaning is a different problem Note: Percentages based on the actual number of respondents to each question
Preserving Cartographic Representation Note: Percentages based on the actual number of respondents to each question