The OpenGov OpenData Portal - GIS Data Tips and Open Resources: 09/01/2006

Friday, September 29, 2006

NGA to Remove Aeronautical Data from Public Access 1 October

The National Geospatial-Intelligence Agency (NGA) will removeits Flight Information Publications (FLIP), the electronic Chart UpdatingManual (eCHUM) and Digital Aeronautical Flight Information File (DAFIFTM)from public access on Oct. 1, 2006. NGA paper map products, to a scale of 1:250,000 to 1:5,000,000 will continueto be made available to the public through FAA sales. In addition, for aperiod of one year (Oct. 1, 2006-Oct. 1, 2007), NGA will distribute adigital product covering U.S. airspace, called U.S. Flight Information File(USFIF) through the Web. (Source: NGA)

Wednesday, September 27, 2006

Stephen F. Austin State University's FRI Lab (Texas)

What a score this resource is for Texas Data... here's just a sampling of what you can access:
Texas DRGs - 24k, 100k and 250k
1m digital orthos
SSURGO soils data
Contours
Seamless DEMs
TIGER data
and much more! This resource is a total score! Bookmark http://www.fri.sfasu.edu/pages/archives/gis_data/html/gis_data.html

Columbia Regional Geospatial Service Center (Texas)

The Columbia Regional Geospatial Service Center (CRGSC) is a fine source for Texas GIS datasets including orthophotos, vector data products, GPS base station locations, Landsat and SPOT imagery, and more. Thanks to Justing for this fine tip! See http://www.crgsc.org/ - See http://www.crgsc.org/

Monday, September 25, 2006

Utah Automated Geographic Reference Center (AGRC)

The Utah Automated Geographic Reference Center (AGRC) provides a wide range of Geographic Information System (GIS) support to the State of Utah. AGRC strives to facilitate coordination among Utah GIS users and effective, efficient use of GIS resources. Available data products for download include DRG, DEM, DOQ, NED, FEMA data and much more. See
http://agrc.its.state.ut.us/

Atlas: The Louisiana Statewide GIS

Search to find mapping data such as Tiger files, geotiff images, and flood data including data from the Louisiana GIS CD. Use live index maps to download DEMs, DRGs and DOQQs for Louisiana - 2004 DOQQs available. See http://atlas.lsu.edu/

Louisiana Geographic Information Center

LAGIC was established by the Louisiana GIS Council (LGISC) and the Louisiana Office of E-Services to facilitate the distribution of geographic information, provide technical assistance, and support GIS data development among state, federal, and local government. Also available at the site are Hurricane Katrina Mapping & Analysis Data, Hurricane Katrina Flood Recovery Data and more. See http://lagic.lsu.edu/

New Jersey Geographic Information Network

NJGIN... The gateway to geospatial information in New Jersey. NJGIN Explorer offers information about a diversity of digital geospatial data available for use with GIS software. Users searching for Ortho photos will have access to 2002 and 1995 photos here. Metadata files are included when imagery is downloaded and data is served as MrSID imagery. Note.. photos are tiled and not carved up by quad index. See https://njgin.state.nj.us/NJ_NJGINExplorer/index.jsp

Geographic Information North Carolina

GINC is North Carolina's State GIS Clearinghouse and hosts several key portals including; North Carolina Center for Geographic Information and Analysis (CGIA) - a division within the Department of Environment and Natural Resources; The NC Corporate Geographic Database (NCCGDB); The Geographic data clearinghouse, and the Geographic Information Coordinating Council. See http://www.cgia.state.nc.us/

New York State GIS Clearinghouse

The NYS GIS Coordinating Body promotes and facilitates the development, effective use, and sharing of geographic information. This is a fine resource for locating GIS data, orthophotos, and educational material within the State of New York.
Recent additions to the portal include:
2004 orthophotos for 7 counties now available
2004 real property data
ALIS road center line data
Digital orthophoto application
See http://www.nysgis.state.ny.us/ Direct download of NY imagery is also provided at http://www.nysgis.state.ny.us/gateway/mg/nysdop_download.htm

Free online imagery covering Australia

Free online imagery covering the Australian landmass, most of Papua New Guinea, Eastern Indonesia and New Zealand is available from Geoscience Australia, ACRES. For more information visit www.ga.gov.au/acres/prod_ser/modisprice.jsp.

Sunday, September 24, 2006

The Texas State Data Center

The Texas State Data Center and Office of the State Demographer. A number of collections by State or County are available (SHP format) as well as a number of Census data products - See http://txsdc.utsa.edu/

Saturday, September 23, 2006

Map data for the Philippines

Free data for many International countries is tough to come by. A reader shares this resource where you can access some data products for the Philippines. Free data includes postal codes, and some topos in SHP format.. See A&A for more http://www.aag.com.ph/products.html

Friday, September 22, 2006

Processed SRTM 90m Digital Elevation Data (DEM) for the Entire Globe

The CGIAR-CSI GeoPortal is now serving up processed SRTM 90M Global DEM data. Digital elevation models (DEM) for nearly the entire globe, covering most of the countries of the world, are available for download on this site. The SRTM 90m DEM's have a resolution of 90m at the equator, and are provided in mosaiced 5 deg x 5 deg tiles for easy download and use. All are produced from a seamless dataset to allow easy mosaicing. These are available in both ArcInfo ASCII and GeoTiff format - see http://srtm.csi.cgiar.org

Thursday, September 21, 2006

NZ Geographical Place Names & Street Names

Names for streets, roads and highways are assigned by the local City or District Council, in accordance with the Local Government Act. Railway names are approved by the NZ Geographic Board, and State Highway numbers are allocated by Transit New Zealand. Downloadable database here - http://www.linz.govt.nz/core/placenames/index.html

GEOnet Names Server (GNS)

The GEOnet Names Server (GNS) provides access to the National Geospatial-Intelligence Agency's (NGA) and the U.S. Board on Geographic Names' (US BGN) database of foreign geographic feature names. The GNS contains 4.0 million features with 5.5 million names - see http://earth-info.nga.mil/gns/html/index.html

GeoDataSource Place names

Another POI database is on the market in the GeoDataSource Cities Database product. The company has several flavors that run as much as $1,000+. A free product is available to those who register. It contains 2 million+ city place names. Not sure how this product differs from some of the widely available free place name products available. See more at http://www.geodatasource.com/cities-free.html - other free place name products can be found here & here for those interested - there's also the ever popular GNS names server at http://earth-info.nga.mil/gns/html/index.html

The ARIA Project Providing Imagery for Arizona

This fine resource from the University of Arizona is an interdisciplinary resource system for digital image and map data for the Sonoran desert region, including the U.S. Southwest and northern Mexico. Users will find instructional and outreach activities in remote sensing and spatial analysis on integrated regional assessments as well as a wealth of data (DRG, DEM, DOQQs) for use in their GIS. In addition to countless research material and educational resources, users will find they are provided with access to plenty of data. Simply click on the "Images" link and you'll find more links leading to 24k, 100k, and 250k DRG, DEM, and imagery. Check it out at http://aria.arizona.edu/

Tuesday, September 19, 2006

KGS GIS Data - Kentucky

Access to all the geological survey's GIS data products including topos, DEMs, transportation data, soils, base maps, political boundaries, hydrology and more. See http://www.uky.edu/KGS/gis/kgs_gis.html

KRGMAPS - Kentucky DRGs

Free download of Kentucky topo maps via a very slick, simple interface. KRGMAPS provides High Resolution Topographic Map Images in Kentucky Single State Plane Zone, NAD 83, US Survey Feet. Available as MrSID or TIF... nice! see http://www.uky.edu/KGS/gis/krgweb/index.html

West Virginia Q3 flood data

Free ftp download of Q3 flood data, DFIRM, and county flood themes - see ftp server at ftp://ftp.wvgis.wvu.edu/pub/Clearinghouse/water_resources/Q3_Flood/

West Virginia State GIS Technical Center

The WV GIS TC has an ambitious goal to provide focus, direction and leadership to users of geographic information systems (GIS), digital mapping and remote sensing within the State of West Virginia. Data hounds will be pleased to find loads of freely available data products available here, in addition to many other useful GIS resources. At the heart of this portal for many users is the data access mechanism. Simply click the "GIS Data" link which will present a pull-down list with tons of thematic layers to select from. See http://wvgis.wvu.edu/index.php

Land Information BC Discovery Service

From the BC Ministry of sustainable resource management (MSRM), discover geospatial datasets for British Columbia. Explore human and cultural data, land info, imagery and base maps, legal/admin and more - see http://srmapps.gov.bc.ca/metastar/browse.do

W. Australia - WALIS

Search the WALIS database for western Australia data products including aerial photography, hydrographic data and much more. See http://waliswww.walis.wa.gov.au/interragator/

Australian Spatial Data Directory (ASDD)

The ASDD is an essential component of the Australian Spatial Data Infrastructure (ASDI). The gateway to the ASDD is maintained by Geoscience Australia on behalf of ANZLIC - the Spatial Information Council, as part of its broader Australian Government responsibility for the ASDI. See http://asdd.ga.gov.au/asdd/search.html

University of Arkansas Spatial Library

The University of Arkansas Spatial Library is a massive (multi-terabyte) Oracle database holding a wide range of geospatial data sets in an OGC-compliant interoperable form. See http://www.cast.uark.edu/UASL/ or jump directly to http://www.cast.uark.edu/UASL/raw_DOQ/index.html
Datasets include DRG, DOQ and landsat imagery

Arizona ALRIS (Arizona Land Resource Information System)

A wealth of Geo data from arizona - available for order for free for non-commercial uses - see http://www.land.state.az.us/alris/

FAO Geonetwork

A number of International datasets availble for download from the FAO - much African data to be found here. See http://www.fao.org/geonetwork/srv/en/main.search

ASTER Data (Advanced Spaceborne Thermal Emission and Reflection Radiometer)

ASTER satelite data can be used to generate Digital Elevation Models (DEMS) with 30m resolution. EOS archives the DEMs in its database so that they will be available immediately upon request.DEMs not available can be ordered. From the JPL - see http://asterweb.jpl.nasa.gov/

DRG update

Thanks to jared over at mapransom for the following update... sounds like the Internet Archive has the data and will be loading shortly... stay tuned. From Jared:
I am waiting on the Internet Archive to make the data available. They have been very busy with their September 11th archive project. I was given a time frame of about a week before raw data would be available. However, that was unfortunately just a guess not a
guarantee. I've been updating the map ransom page as I get more information.

Kansas Geospatial Community Commons

The Kansas Geospatial Community Commons (KGCC) is an initiative of the Kansas GIS Policy Board and the Data Access & Support Center (DASC). KGCC is designed to be a place for state and local governments and the private sector to share & discover geospatial information & connect with the Kansas GIS community. Simply click the browse link to access a directory of available data products which include elevation products (LIDAR, NED), topo (DRGs clipped) , imagery (tons of imagery!) and more. See http://www.kansasgis.org (thanks to Beau for this suggestion!)

Maine GIS Data Catalog

The purpose of this Data Catalog is to provide the public with access to the digital geographic data produced by the GIS Executive Council, and Maine GeoLibrary Board. The Data Catalog is hosted and maintained by the Maine Office of GIS (MEGIS). Data are referenced by UTM Zone 19, meters, NAD 83. Access contours, DRGs, hurricane data and much moreSee http://apollo.ogis.state.me.us/catalog/ - See http://apollo.ogis.state.me.us/catalog/

Florida GIS Data from LABINS

LABINS (Land Boundary Information System) has DOQQS, DRG, DEM, DLG, NWI, survey data (horizontal and vertical control) and much more for the State of Florida - See http://data.labins.org/2003/

MIT/MassGIS Digital Orthophoto Project

Say no more... Orthophotos... lots of em for MASS! Developed and hosted by the M.I.T. Dept. of Urban Studies and Planning. See http://ortho.mit.edu/nsdi/

MetroGIS (Minnesota) DataFinder Catalog

DataFinders is a one-stop-shop for discovering geospatial data pertaining to the seven county Minneapolis-St. Paul Metropolitan Area. Its primary function is to facilitate sharing of GIS (Geographic Information System) data among organizations serving the Twin Cities Metropolitan Area of Minnesota. DataFinder provides metadata describing GIS data sets, many of which can be directly downloaded. Currently, there are metadata for 205 datasets available on the DataFinder site. Many data themes are available including land ownership, elevation data, geology, demographics and much more. See http://www.datafinder.org

Michigan Geographic Data Library

Serves as the state's repository of digital geographic information. This site currently contains over 60 unique statewide datasets including the state's basemap (MI Geographic Framework), aerial imagery, geology, hydrography, land ownership, topography, and much more. See http://www.mcgi.state.mi.us/mgdl/ - 1998 DOQQs are available for download

News - State of Michigan Imagery Grant Partnership Opportunity

ANN: Phase 1 Grant Period: 2005 - 2009 (Application Deadline 07/1/2008)The purpose of the Grant Partnership is to enable the State of Michigan (SOM) to purchase rights to Orthoimages. The SOM will use the original products INTERNALLY among all SOM State Agencies and their contractors for the duration of a project. SOM needs imagery that is leaf-off and at least 2-foot pixel or better. It can be either black and white or natural color. See Here

Saskatchewan Protected Areas

Saskatchewan Designated and Protected Areas Digital Data - The Saskatchewan Designated Areas Data project was created to map land currently described in text (usually in gazette form) and to provide access to this geospatial data through systems that comply with national standards. The described "designated lands" include the various National and Provincial Park lands (i.e. Historic Parks, Park Reserves, Recreation Sites); environmentally sensitive lands (i.e. Wildlife Habitat Protection Act Lands, Fish and Wildlife Development Fund Lands, Game Preserves); and some privately owned lands (i.e. Conservation Easements, Ducks Unlimited Lands, Saskatchewan Wildlife Federation Lands). Downloadable data or IMS available - see http://gisweb1.serm.gov.sk.ca/DesignatedAreasProject/DA_distribution/da_distribution.htm

Monday, September 18, 2006

MassGIS - Massachusetts GIS Data

MassGIS data contains pretty much any GIS dataset for Massachusettes that you could need. Conveniently organized by either raster of vector datasets you can spend hours here! ESRI Shapefiles, tiled by Town, USGS Quad, OQ Quad, Basin, Watershed, State, NE. See http://www.mass.gov/mgis/download.htm or http://www.mass.gov/mgis/ftpstate.htm

Nova Scotia Geographic Information Services

Geographic Information Services develops, maintains and distributes the province’s corporate, primary geographic information including the Nova Scotia Topographic Database, the Nova Scotia Coordinate Reference System, the Nova Scotia Property Records Database, and the Nova Scotia Aerial Photography Archive. Geomatics products consist of maps, databases and aerial photographs. Access 1:10k digital topos, NS roads and elevation data, and the GeoNova map portal - see http://www.gov.ns.ca/snsmr/land/

BC Integrated Land Management Data

Numerous, free digital map files for the Province of British Columbia. Not a ton of free, useful datasets, however, not bad for a Canadian resource! See http://ilmbwww.gov.bc.ca/bmgs/freestuff.html

Manitoba Land Initiative

The Manitoba Land Initiative Web site is the source for geo-spatial information from the Government of Manitoba. It is intended for both the GIS expert and the decision maker. This Web site allows on-line access to the MLI corporate land data warehouse. See https://web2.gov.mb.ca/mli/index.html

Free New York DRG (FTP)

Free download of all DRG files for New York. Conveniently made available via FTP by PASDA - See ftp://www.pasda.psu.edu/pub/pasda/other_states/ny/drg24k/

North Carolina DRGs

FTP access to download all the North Carolina DRGs - provided by PASDA - see ftp://www.pasda.psu.edu/pub/pasda/other_states/nc/drg24k/

Texas DRGs - TNRIS Data Distribution System

Freely downloadble DRGs for all of Texas here on this resource from TNRIS. Simply click on a county, enter a quade name or enter the lat/long. Your hit will return downloadable 30m DEM or a 24k DRG file - See http://www.tnris.state.tx.us/digital.htm

Pennsylvania DRG FTP site from PASDA

Freely download PENN State DRGs via FTP from PASDA. Fast simple download provided as well as Metadata - See http://www.pasda.psu.edu/access/drg24klist.cgi

GeoBase - geospatial data for Canada

GeoBase is a federal, provincial and territorial government initiative that is overseen by the Canadian Council on Geomatics (CCOG). It is undertaken to ensure the provision of, and access to, a common, up-to-date and maintained base of quality geospatial data for all of Canada. Through the GeoBase portal, users with an interest in the field of geomatics have access to quality geospatial information at no cost and with unrestricted use. The WMS permits direct access to GeoBase data through WMS functionalities following Open GeoSpatial Consortium (OGC) standards. USe Geobase to access elevation data, topop datasets, road networks, LandSat imagery and control, admin boundaries, and more - See http://www.geobase.ca/

Sunday, September 17, 2006

Free Alaska Cadastral GIS data

A number of free datasets for Alaska including shoreline, planning areas and much more. Be sure to scroll to the bottom for GIS data - See http://www.mms.gov/ld/alaska.htm

UCONN MAGIC - Free Connecticut GIS data

UCONN MAGIC data center provides tons of orthos for the State. A fabulous quad search will reveal an extensive data products freely available for the quad selected. Data available include DRG, DEM, DOQ, hydro, rail, and quad boundaries. See http://magic.lib.uconn.edu/

Tennessee Spatial Data Server

The ultimate Tennessee spatial data repository where you can access and download DRG, DOQ, DEM, Census data and much more. Downloadable by quad or county - see http://www.tngis.org/ Also available are special data layers like streams, soils data, PLSS data, roads and more

WGIAC - Wyoming DRGs

Free DRGs (24k, 100k, 250k) for Wyoming - easily located by searching a quad directory listing or using a clickable map. GeoTIFFs are ZIP commpressed - See http://wgiac.state.wy.us/html/AboutDRG.asp

GeoData.gov

The ultimate U.S map service. Use this spatial repository and web service to locate GIS data and data services including pretty much any data theme you can think of... hurricane tracks, wildfire info, census data, topography, etc... See http://geodata.gov/ or go directly to http://gos2.geodata.gov/wps/portal/gos

GeoConnections Free Data Directory

Free data available via the web.. thousands of data themes are listed in this convenient database which is constantly updated and easily searched. See http://www.geoconnections.org/CGDI.cfm/fuseaction/data.free/gcs.cfm - See also this database from CGDI

GeoGratis - Canada's Geospatial Data Clearinghouse

GeoGratis is a web and file transfer protocol (ftp) site that distributes geospatial data of Canada. Data is available for download, without charge. Vector mapping data is available in scales ranging from 1:50 000 to 1:30 000 000 in a variety of file formats. Not all vector layers are in all scales - FTP downloads available. Downlaod top base maps, geo-political maps and boundaries, and VMAP level 0 (VMAP0) of Canada. See http://geogratis.cgdi.gc.ca/clf/en

Global Population Database (GPOPDB)

The Global Population Database (GPOPDB) is used to map the populations of many countries around the world. The database uses a rectangular grid for mapping of 20 minutes of latitude by 30 minutes of longitude (about 2,000 square kilometers at the equator). For urban areas of more than 25,000 people, density circles are drawn to provide more detail. Population data is primarily obtained through censuses, surveys and maps from the Bureau of the Census Library or from the countries themselves. Detailed data are obtained by working from the national totals towards the first-order administrative levels; typically state, province or region. See
http://www.ciesin.org/datasets/cir/gpopdb-home.html &
ftp://ftp.ciesin.org/pub/data/Global_Pop_DB

Canadian Geographical Names

Query this extensive database by name, geography, or postal code. Digital data products are available for purchase. See http://geonames.nrcan.gc.ca/

NGA GEOnet Names Server (GNS

The GEOnet Names Server (GNS) provides access to the National Geospatial-Intelligence Agency's (NGA) and the U.S. Board on Geographic Names' (US BGN) database of foreign geographic feature names. The database is the official repository of foreign place-name decisions approved by the US BGN. Approximately 20,000 of the database's features are updated monthly. http://earth-info.nga.mil/gns/html/

Geonames - place names and post codes

The Geonames web resource has been totally revamped and now sports a very simple user interface for searching place names.A nice feature is the ability to dump all the data into a simple txt file for use within any GIS. See http://www.geonames.org/ or jump directly to http://www.geonames.org/export/ to export these data.

Saturday, September 16, 2006

MODIS, 16-Day NDVI

Normalized Difference Vegetation Index (NDVI) derived from MODIS data is provided here on a 16 day basis for the conterminous United States. The original band files used to derive the NDVI are also available and a band file with cloud information (for data from 2001 to the present). Data are in GeoTIFF and have been projected to Alber's. See http://glcfapp.umiacs.umd.edu:8080/esdi/product?productID=19

US Census Bureau FTP Access

NEed Census data... how about a simply FTP server to access them? US Census Bureau's FT site providing quick and easy access via FTP to a huge assortment of data products, categorized by decade (1980, 90, and 2000) http://www2.census.gov/

US Large Scale (24k) DLG data (ftp)

Need DLGs? Look no more! The 1:24,000-scale DEM data archived here at the EROS site is divided just like 7.5' paper maps into 7.5 x 7.5-minute sets indexed by the USGS quadrangle name. Use the FTP by Alphabetical List site if the name of the FTP via Graphics to search for the desired data. The data is registered using metric UTM values according to NAD27. Grid cell elevations are presented in meters. http://edcftp.cr.usgs.gov/pub/data/DLG/LARGE_SCALE/

SRTM DTED Level 2 - 1 arc second data

Shuttle Radar Topography Mission DTED® Level 2 (1 arc second) Data on DVD (United States and Territorial Islands) -- SRTM DTED® is a uniform matrix of elevation values indexed to specific points on the ground. The horizontal datum is the World Geodetic System 1984 (WGS84) and the vertical datum is mean sea level as determined by the WGS84 Earth Gravitational Model (EGM 96) geoid. The elevation data are with respect to the reflective surface, which may be vegetation, man-made features or bare earth. DTED® Level 2 elevation values are spaced one arc second apart between 0 degrees and 50 degrees latitude, and spaced one arc second apart in latitude and two arc seconds apart in longitude between 50 degrees and 60 degrees latitude. SRTM DTED® Level 1 values are derived from the SRTM DTED® 2 values such that the DTED® 1 values are identical to the DTED® 2 values at coincident points. However, the SRTM DTED® 1 values are spaced 3 arc seconds apart between 0 degrees and 50 degrees latitude, and spaced 3 arc seconds apart in latitude and 6 arc seconds apart in longitude between 50 degrees and 60 degrees latitude. These data are now available on a cost recovery basis and can be ordered on CD-ROM for a mere $60 per CD http://edcsns17.cr.usgs.gov/srtmdted2/ See also the level 1 - 3 arc second Global data product http://edcsns17.cr.usgs.gov/srtm/

2-Minute Gridded Global Relief Data (ETOPO2)

Two-minute gridded global relief for both ocean and land areas (combined bathymetry and topography) are available in the ETOPO2 database. These data are available via download or can be ordered on CD-ROM - See http://www.ngdc.noaa.gov/mgg/global/relief/ETOPO2/

Vector Shorelines for the U.S. Gulf of Mexico

There are nine GIS data layers offered for each state in the Gulf of Mexico. These include: four vector shorelines, an offshore baseline used for generating shore-normal transects, transects for long- and short- term shoreline change rates, transect/shoreline intersection positions, and a vector layer to show the spatial extents of beach nourishment projects. See http://pubs.usgs.gov/of/2004/1089/gis-data.html

ATDI Free Digital Elevation Model (DEM) Server

Just enter the coordinates of a spot to download a DEM in SDTS format - The cartographic data proposed here is in SDTS format http://www.atdi-us.com/SDTS_DL_b.htm

North American Transportation Atlas Data (NORTAD)

A comprehensive, free transportation database with data themes and layers for Canada, USA, and Mexico. Data layers include highways, airports, ports, rail, and other transportation routes. Order on CD or simply download for free.. translation routines are also available.
http://www.bts.gov/publications/north_american_transportation_atlas_data/

USDA Geospatial DOQQ Data Server

Users of this USDA server wil find DRGs and DOQQs served up in NAD83 and NAD27http://ortho.ftw.nrcs.usda.gov/

Libre Map Project - free DRG project

An effort to make the entire USGS DRG set freely available to the public via the Internet Archive. See http://libre.redjar.org/maps/

Thursday, September 14, 2006

California Landsat Images

This product was created by the U.S. Geological Survey (USGS) and contains Landsat data files in Geographic Tagged Image-File Format (GeoTIFF). The images have all been reprojected to the California Albers Projection, NAD 83 datum, and provided in GeoTiff format. Images from Landsat5 and Landsat7 available - see http://archive.casil.ucdavis.edu/casil/remote_sensing/landsat/

California DRGs from CASIL

The maps are organized into 1x1 degree blocks covering the state of California. The source maps for DRGs were georeferenced to the UTM grid, but DRG images for California are available in Albers equal area projection (see the projection information). A DRG is useful as a source or background layer in a GIS, as a means to perform quality assurance on other digital products, and as a source for the collection and revision of DLG data. Available as 7.5 minute, 30x60 minute, and 1x1 degree blocks - see http://archive.casil.ucdavis.edu/casil/maps/drg/ see also http://gis.ca.gov/DRG.epl

INTERIM 2005 National Agriculture Imagery Program (NAIP) County Compressed Mosaics

NAIP imagery is one-meter color Digital Orthophoto Quarter Quads (DOQQs) for the entire State of California. This is the first time that California has acquired one-meter natural DOQQs statewide in a single "season"/year. The Interim 2005 County compressed (15:1) mosaics are in MrSID format. See http://archive.casil.ucdavis.edu/casil/remote_sensing/naip_2005/

California Digital Ortho (Quarter) Quads DOQQs

CASIL provides users with access to California State DOQQs - available via FTP as MrSID - see http://archive.casil.ucdavis.edu/casil/remote_sensing/doq/

Arkansas Spatial Analysis Lab

Loads of Arkansas data readily available here including ALL the DRGs - 1:24k, 1:100k, and 1:250k collared, collarless, and hillshaded. A nice UI makes it very simple to locate and download the DRGs. DOQQs and 10m DEMs are also available for download - see http://sal.uamont.edu/pages/nsdd/Arkansas_State.htm

U Arkansas GeoStor

GeoStor provides DOQQs, DRGs and much more in an FTP-able format. You'll find 1990 and 2002 DOQQs in MrSID and TIF formats. There's also Landsat images as well as 1:24k DRGs - See http://www.cast.uark.edu/cast/geostor/raw_DOQ/index.html

Tuesday, September 12, 2006

German Environmental Information Portal

PortalU was designed as the central online access-point to government-owned environmental information and data in Germany. PortalU offers access to more than 1.000.000 web-pages and database records from federal and state authorities - See http://www.portalu.de (Thanks to the OGC news for a tip about this resource)

HYDRO1k Elevation Derivative Database (USGS)

HYDRO1k is a geographic database developed to provide comprehensive and consistent global coverage of topographically derived data sets, including streams, drainage basins and ancillary layers derived from the USGS' 30 arc-second digital elevation model of the world (GTOPO30). HYDRO1k provides a suite of geo-referenced data sets, both raster and vector, which will be of value for all users who need to organize, evaluate, or process hydrologic information on a continental scale. These data are freely available via FTP from the USGS... enjoy! http://edc.usgs.gov/products/elevation/gtopo30/hydro/index.html

Monday, September 11, 2006

Alaska State geospatial data clearinghouse

The asgdc provides access to a wealth of data for the state of Alaska. See http://www.asgdc.state.ak.us/. Looking for Alaska DRG, DEMs (7.5 m), and DLG data? See http://agdc.usgs.gov/data/usgs/to_geo.html

National Hydrographic database (NHD)

The National Hydrography Dataset is now available in a new database design that allows better web-based access and query, as well as truly seamless data that can be downloaded in various extents. The new database design provides a distribution format called NHDinGEO. Data requests in NHDinGEO can be extracted by subbasin, county, congressional district or by topographic map quad. Pre-staged personal geodatabases by subregion are now available on the ftp site ftp://nhdftp.usgs.gov/SubRegions. Select the High, Local, or Medium folder. See also http://nhd.usgs.gov/data.html

State of Colorado - special boundaries

The State of Colorado has several datasets available here including county boundaries (Arc Export format), Title 32 special district boundaries, school distrivt boundaries, census data, and more - see http://dola.colorado.gov/demog/GIS/DataAssets.htm

New York State GIS Clearinghouse

NYS clearinghouse makes available a ton of freely available data products including DEM, DRG, DLG, DOQ, FEMA, and much more. Jump to http://www.nysgis.state.ny.us/gisdata/

State of Alabama DRGs

The State of Alabam Geological Society makes available free DRGs for download (TIF format .zip compressed) at scales of 1:24,000, 1:100,000, and 1:250,000. The resource also makes available Hydrologic units (HUC) as well as counties and topo map coverages. See http://www.gsa.state.al.us/gsa/GIS/DATA.html

Friday, September 08, 2006

Washington state GIS Data - UW Geology Dept.

UW Geology is a fabulous resource providing simple and fast access to Washington State DRG, DOQ, clipped DRGs and 10m DEMs...

Washington DRG locator

The Washington DRG locator is a decent resource when users can easily go in, click on a map, and download a DRG. Simply click the keymap to reveal a lengthy listing of all the quads available for the sector you selected. Files are ZIP compressed and you can easily move up to the parent and grab all the data in one swoop.

State of Oregon DRG Locator

The State of Oregon DRG locator is a decent resource when users can easily go in, click on a map, and download a DRG. Simply click the keymap to reveal a lengthy listing of all the quads available for the sector you selected. Files are ZIP compressed and you can easily move up to the parent and grab all the data in one swoop.

Welcome to free gis data

Ya i know, you might be thinking, what, another resource listing free GIS data resources?? You betcha... but not just "another" site full of links.... since I've got access to a wealth of contacts and data links via the years that I've been managing and running popular GIS news portals I'm now pleased to share with the GIS user community a collection of all the best places to access and download free GIS data... enjoy and please be sure to suggest resources if you think they should be listed here.