National Geospatial Data Clearinghouse

• Distributed service to locate geospatial data based on their characteristics expressed in metadata

• Clearinghouse allows one to pose a query of all or a portion of the community in a single session

• Like a spatial AltaVista

• There are three functional areas that interact to create the Clearinghouse:
• Metadata preparation and indexing
• Metadata service
• User Access via Gateway forms

• The Clearinghouse in its distributed form includes a registry of servers, several WWW-to-Z39.50 gateways, and many Z39.50 servers

• A primary goal of Clearinghouse is the ability to find spatial data throughout the entire community, not one site at a time

• User downloads query form

• User sends query to Web server

• Gateway passes query to clearinghouse servers

• Gateway receives and collates response as list of "hits"

• Client receives results summary as HTML by default

• Client can request a specific metadata record for viewing

• Numerous software solutions available

• Commercial and free-ware

• Standalone, DB-linked, GIS-linked

• Permit collection and structuring of FGDC-compatible metadata

• Present metadata as HTML, XML, or text

• Z39.50 Protocol is used

• "GEO" Geospatial Metadata Profile is published for Z39.50 implementors to understand FGDC metadata structures

• Supports search across numeric, text, date, and spatial extent and full-text

• Freeware and commercial solutions

• User Interfaces

• HTML-based forms hosted at Gateways are the primary access method

• Java map-based interface from MEL allows more sophisticated search

• Inclusion of search capabilities in GIS client software is possible

• 109 Nodes (servers) online as of 3/1/99
• 28 Federal, national scope
• 35 State/University state-wide scope
• 28 International scope or location
• 18 Local or Regional scope

Federal Participation

• NOAA (10)
• USGS (6)
• FEMA (sampler)
• NRCS climate and soils
• CIESIN/EPA
• CIESIN/NASA
• DOT NTAD
• National Park Service
• Army Corps of Engineers
• Tri-Services Center
• National Wetlands Inventory
• Census (sampler)
• Minerals Management Service

State Participation

• New York (2)
• North Carolina
• Oklahoma
• Kansas
• Texas
• Montana (3)
• Vermont
• Pennsylvania
• West Virginia
• Washington
• Wisconsin
• Wyoming (2)
• Florida
• Alabama
• New Mexico
• Arizona
• Georgia
• Illinois
• Minnesota
• Alaska
• California
• Delaware
• Nebraska
• New Jersey

Regional/Local Participation

• McKinley Co, NM
• City of Santa Fe, NM
• North Texas GIS
• Research Planning
• Sabine R Authority, TX
• San Francisco Bay
• S Florida Ecosystem
• SW Natural Resources
• Olympic Peninsula, WA
• Greater Yellowstone
• Helena NF
• Ecological Reserves, KS
• MIT/Mass Boston DOQs
• Great Lakes EIS
• Eastern Sierra

International Participation

• NOAA/Japan GOIN
• South Africa (2)
• ESA AVHRR sampler
• GELOS, Italy
• PAIGH, Mexico
• S57 Hydrography, Canada
• NRL MEL
• Africa DDS
• Inter-American Geospatial Data Network
• Hong Kong
• CIESIN/USDA Global Environmental Change
• Australia (10+)
• Costa Rica
• Caribbean CEPNET, Jamaica

Planned or Funded Nodes

• Mt. Desert Island, ME
• SW Washington COG
• NASA GCMD
• CODEPLAN, Brazil
• Iowa
• Missouri
• Kentucky
• South Dakota
• Oregon
• Louisiana
• Ohio
• Connecticut MAGIC
• Colorado
• NW Ecosystems

For more information:

Visit the FGDC Web site:
http://www.fgdc.gov

Contact the Clearinghouse Coordinator, Doug Nebert ddnebert@usgs.gov