The Scripps Orbit and Permanent Array Center (SOPAC) is located at the
Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics
(IGPP), Scripps Institution of Oceanography
(SIO), University of California, San Diego (UCSD) in La Jolla, California. SOPAC's primary scientific role is to support high precision geodetic and geophysical measurements using Global Positioning System (GPS) satellites, particularly for the study of earthquake hazards, tectonic plate motion, plate boundary deformation, and meteorological processes. SOPAC investigators also conduct research on the implementation, operation and scientific applications of continuously monitoring GPS arrays and Synthetic Aperture Radar (SAR) interferometry.
SOPAC is a major participant in the International GPS Service
(IGS), serving as a Global Data Center
and a Global Analysis Center. SOPAC is the archive for the 250-station Southern
California Integrated GPS Network (SCIGN),
as well as an analysis center and a data retrieval facility. SOPAC maintains
an archive of regional continuous GPS data for
UNAVCO, Inc. focusing on the Western North America plate boundary and is
developing a seamless archive interface for UNAVCO. SOPAC performs research and
provides operational support for NOAA's Forecast Applications Branch
(FAB) real-time GPS meteorology project
for short-term weather forecasting. SOPAC also provides essential infrastructure
support for the California Spatial Reference Center
(CSRC), a partnership with the National
Geodetic Survey (NGS).
SOPAC provides precise, rapid, ultra-rapid, and hourly orbits for the International
GPS Service (IGS) and NOAA's Forecast Systems Laboratory (FSL).
Many GPS-related services and tools are available from the SOPAC Web site,
such as SCOUT (an ITRF Coordinates Generator;
15 minute turnaround time), Site Information Manager
(SIM), and a utility to check for
unused 4-character site codes.
SOPAC archives 24-hour RINEX data from about 800 continuous GPS sites from
more than 20 scientific networks around the world, including the 250-station
Southern California Integrated GPS Network (SCIGN).
SOPAC also helps maintain the operational center for the California Spatial
Reference Center (CSRC). The CSRC provides California's
geodetic framework for scientific, surveying, engineering, and geographical information
systems in partnership with the National Geodetic Survey and
Caltrans. SOPAC also collects and archives high-rate (1 Hz), low latency (1-2 seconds)
GPS data from stations in California.
SOPAC provides the following services and products to the scientific community:
Precise near real-time and predicted GPS satellite orbits,
Precise polar motion and Earth rotation variations,
On-line GARNER data archive of continuously operating GPS tracking stations,
for data collected since 1990,
Time series of daily three-dimensional positions for the global and California
stations with respect to the International Terrestrial Reference Frame (ITRF),
Software for remote downloading of continuous GPS data,
Consultation on installation and operations of continuous GPS arrays.