National Geodetic Survey -with links to CORS data & software, including free download of Geoid 2003 software.
US Coast Guard Navigation Center -GPS Information
GPS Notice Advisory to Navigation Users (NANU) -GPS constellation status
US Forest Service GPS Page -with links to GPS Community Base Station Data
Civil GPS Service Interface Committee -the recognized worldwide forum for interaction between civil GPS Users and U.S. GPS authorities.
GPS Report-A-Problem Worksheet -to report degradations, outages, or other incidents or anomalies affecting GPS service.
Geomagnetic Activity Affecting GPS - K-indices of 5 or greater, indicated on the chart in red, indicate storm-level geomagnetic activity that may affect GPS.
USGS Cascades Volcano Observatory; Vancouver, WA -volcano Monitoring with GPS
Of Pacific Northwest Interest:
The Oregon Department of Transportation's Geometronics Unit has established the Oregon Real Time GPS Network in cooperation with other state, local, and government agencies and private companies.
The ESRI PRJ files for OCRS projections are already on the ODOT OCRS website. Here's the link:
To see a map of the ORGN base station locations with an interactive map, go to this link:
Link to the Washington State Reference Network. Testing accounts are free for 90 days.
UNAVCO Plate Boundary Observatory - responsible for the installation of 149 permanent GPS stations and 8 Strainmeter/Tiltmeter stations in Oregon, Washington, and Idaho.
Oregon State University/Rensselaer Polytechnic Institute - monitoring geodetic motions in the US Pacific Northwest (data available)
University of Washington Geodesy/Geophysics -Pacific Northwest Geodetic Array (PANGA)
The Geographer's Craft Project, GPS Resource: Department of Geography, The University of Colorado at Boulder
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