July 22, 2009

Plate Boundary Observatory P475 Point Loma is online via HPWREN

By Chris Walls Plate Boundary Observatory - EarthScope - UNAVCO, Inc.

The HPWREN cyberinfrastructure has enhanced the science and public service applications of an EarthScope GPS station at Point Loma, San Diego, California. The Plate Boundary Observatory GPS station P475 is a strategic site to the earthquake science community due to its position relative to the Rose Canyon fault and the offshore borderlands fault system. It is also an important survey control point for City, County and State engineers. The Plate Boundary Observatory (PBO) received multiple requests from both the earthquake and survey communities for high rate, high completeness and low latency data to facilitate a variety of uses such as earthquake early warning prototype testing and real-time kinematic surveying.

P475 Plate Boundary Observatory GPS station near the new lighthouse at Point Loma

Since it was clear the GPS site fulfilled a unique role to multiple users PBO attempted to accommodate the requests using standardized cellular communication equipment. However, cellular communications were inadequate for effectively streaming data due to local topography and episodic radio frequency interference. Installing alternative communication equipment such as a VSat system or autonomous telemetry nodes would have added substantial cost and involved further permitting.

The PBO station is in close proximity to the HPWREN site at Zone3 of the NPS Cabrillo National Monument.

With P475 on the HPWREN data latency is <<1 second and data completeness is at 100% which is fully adequate for end user needs. Furthermore, PBO will save substantial communications costs in the forthcoming years; a double benefit. Our thanks goes to HPWREN.

After installing a radio, the PBO station began to immediately communicate via the same microwave tower facility that the rest of the Cabrillo National Monument installations use for communications via HPWREN, and which is described at http://hpwren.ucsd.edu/news/20070511/.

Main HPWREN web site (includes information for acknowledgments/disclaimers and feedback/contact)