Preserving State and Local Government Digital Geospatial Data Steve MorrisHead of Digital Library InitiativesNorth Carolina State University Libraries

ALA NDIIPP Symposium June 25, 2007

Note: Percentages based on the actual number of respondents to each question 2

NC Geospatial Data Archiving Project

Partnership between university library (NCSU) and state agency (NC Center for Geographic Information & Analysis)Focus on state and local geospatial content in North Carolina (state demonstration)Tied to NC OneMap initiative, which provides for seamless access to data, metadata, and inventoriesObjective: engage existing state/federal geospatial data infrastructures in preservation

Serve as catalyst for discussion within industry

Note: Percentages based on the actual number of respondents to each question 3

NCGDAP: Targeted Content

Resource TypesGIS “vector” (point/line/polygon) dataDigital orthophotography Digital mapsTabular data (e.g. assessment data)

Content ProducersMostly state, local, regional agenciesSome university, not-for-profit, commercialSelected local federal projects

Note: Percentages based on the actual number of respondents to each question 4

Targeted data: Vector data

Cadastral (tax parcels) Street centerlinesZoningTopographic contoursSchool, sheriff, fireVoting precinctsMore …

• 98 of 100 NC counties have GIS• More detailed, accurate, current• Subject to frequent update

Note: Percentages based on the actual number of respondents to each question 5

Targeted data: Digital orthophotography

• 90+ NC counties with orthophotos• 1-5 flights per county• 30-300 gb per flight

Note: Percentages based on the actual number of respondents to each question 6

GIS Software

Software project file (.mxd, .apr, …)

Data layer file (.avl, .lyr, …)

PDF map exports

Web Services-based representations

Targeted data: Cartographic

Note: Percentages based on the actual number of respondents to each question 7

Not yet targeted data: Place-based data

Mobile, LBS, and, social networking applications

Long-term cultural heritage value in non-overhead imagery: more descriptive of place and function

Oblique Imagery

DOT Videologs

Tax Dept. Photos

Street View Images

Note: Percentages based on the actual number of respondents to each question 8

Risks to Digital Geospatial Data

.shp

.mif

.gml

.e00

.dwg

.dgn

.bsb

.bil

.sid

Note: Percentages based on the actual number of respondents to each question 9

Risks to State/Local Geospatial Data

Producer focus on current dataData overwrite as common practice

Future support of data formats in questionNo open, supported format for vector data

Shift to web services-based accessData becoming more ephemeral

Inadequate or nonexistent metadataImpedes discovery and use

Increasing use of spatial databases for data management

The whole is greater than the sum of the parts

Note: Percentages based on the actual number of respondents to each question 10

Local Applications Where GIS Is Used

0%

20%

40%

60%

80%

100%

Economic Development Emergency Management

GIS/ Mapping Planning/ Community Development

Police/ Public Safety Public Works

Utilities Water/ Waste Water

Source: NC OneMap Data Inventory 2004

Note: Percentages based on the actual number of respondents to each question 11

Temporal Data Supports Decision-Making

Land use change analysisReal estate trend analysisSite selection (past uses?)

Forecasting

Parcel Boundary Changes 2001-2004

North Raleigh, NC

Note: Percentages based on the actual number of respondents to each question 12

Suburban Development 1993/2002

Near Mecklenburg-Cabarrus County border

Temporal Data Supports Decision-Making

13

Wake County, NC

Interstate 540 / US Highway 70

Interchange

Near Raleigh/DurhamInternational Airport

2005 Wake County Ortho

14

Note: Percentages based on the actual number of respondents to each question 15

Today’s geospatial data as tomorrow’s cultural heritage

Future uses of data are difficult to anticipate (as with Sanborn Maps).

Note: Percentages based on the actual number of respondents to each question 16

Challenge: Vector Data Formats

No widely-supported, open vector formats for geospatial data

Spatial Data Transfer Standard (SDTS) not widely supportedGeography Markup Language (GML) – diversity of application schemas and profiles threatens permanent access

Spatial DatabasesThe whole is more than the sum of the parts, and the whole is very difficult to preserveCan export individual data layers for curationSome thinking of using the spatial database as the primary archival platform

Note: Percentages based on the actual number of respondents to each question 17

Challenge: Cartographic Representation

Counterpart to the map is not just the dataset but also models, symbolization, classification, annotation, etc.

Note: Percentages based on the actual number of respondents to each question 18

Challenge: Geospatial Web Services

• How to capture records from decision- making processes?• Possible: Atlas collections from automated image capture• Web 2.0 impact: Emerging tiling and caching schemes (archive target?)

Note: Percentages based on the actual number of respondents to each question 19

Challenge: Preservation Metadata

Metadata Archived?

0.0%10.0%20.0%30.0%40.0%50.0%60.0%70.0%

FGDC format Locally definedmetadata

NC OneMapmetadata starter

block

None

% o

f R

esp

on

den

ts

Results from a 2006 survey of all 100 NC counties and 25 largest NC municipalities

Note: Percentages based on the actual number of respondents to each question 20

NCGDAP Project Directions

Working with state spatial data infrastructure on content exchange mechanisms

Infrastructure being created for other business reasonsBenefit to archive in terms of lower acquisition costs, better metadata, established provennance

Co-established the Data Preservation Working Group in the Open Geospatial Consortium

Insert temporal use cases into specification processes

Collaboration with State ArchivesWork towards infusing local records outreach and records retention with geospatial components

Note: Percentages based on the actual number of respondents to each question 21

Questions?

Steve MorrisHead, Digital Library InitiativesNCSU Librariesph: (919) 515-1361Steven_Morris@ncsu.edu

http://www.lib.ncsu.edu/ncgdap