For the State of California, locating a main State GIS data node is relatively simple... enter California Spatial Information Library (CASIL). For direct access to data, see the "data Collections" link (left side-bar) and browse the frequently collected datasets category where you'll find access to admin layers (parks, water districts etc...), cultural data layers (census data), imagery, physical data products and much more. Perhaps of greatest interest is the imagery - Digital Orthophoto Quadrangle GeoTiff (DOQQ), SPOT imagery and much more.
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
California Spatial Information Library (CASIL). Most data are maintained in an Albers projectionCalifornia Spatial Information Library - CaSIL Home http://gis.ca.gov/
DEMs
And here's a total score if you need 7.5 minute Digital Elevation Models for California
1:24,000-scale quadrangles can be access via http://130.166.124.2/ca_index.html
or view these data using a map UI
http://130.166.124.2/ca_dems.2/clickable/overview.htm
In addition to providing a vast amount of geospatial data products, CASIL is also hosting several fine webmapping services. These include:
- CaSIL GeoFinder - GeoFinder is a tool that helps find and retrieve geographic and environmental data from the California Resources Agency
- DRG Mapsurfer This site provides an interface for downloading USGS DRGs for California. Also has the capability to display DOQQs as well as Landsat color composites to enhance the browsing experience.
Esri devMeetUps - locate a developer meetup taking place in a city near you
ERDAS Webinars - Register for a free, online webinar from ERDAS
ILMF 2012 - International LiDAR Mapping Forum, Denver, Colorado, Jan 23-25, 2012
Esri Dev Summit - The Esri Developer Summit (DevSummit) brings together developers and GIS professionals from all over the globe. March 26-29, 2012, Palm Springs, CA
Where2.0 - where the people working on and using location technologies come together to explore best practices and emerging trends in software development, tools, business strategies, and marketing. April 2-4, 20112, San Francisco, CA
For the State of California, locating a main State GIS data node is relatively simple... enter California Spatial Information Library (CASIL). For direct access to data, see the "data Collections" link (left side-bar) and browse the frequently collected datasets category where you'll find access to admin layers (parks, water districts etc...), cultural data layers (census data), imagery, physical data products and much more. Perhaps of greatest interest is the imagery - Digital Orthophoto Quadrangle GeoTiff (DOQQ), SPOT imagery and much more.
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