Enhancing the Network of the Americas (NOTA) GNSS Network for Early Warning Applications

Date: 4/25/2019

Time: 06:00 PM

Room: Grand Ballroom

The GNSS Network of the Americas (NOTA) includes 1100 Plate Boundary Observatory (PBO) sites in the US, 132 COCONet sites in the Caribbean and 40 TLALOCNet sites across Mexico. The NOTA GNSS Network component along the West Coast, funded by the NSF and operated by UNAVCO, is comprised of 754 permanent GPS and GNSS stations spanning three principal tectonic regimes. While NOTA was originally designed for tectonic and volcanic analysis using 24-hr daily files, it has proven to be of significant value to stakeholders who use real-time data streams for early warning systems. 639 of NOTA stations in California, Oregon, and Washington are currently streaming data in real-time, the majority of stations located along plate boundaries of the Cascadia subduction zone and the San Andreas Fault system. 1 Hz real-time data are available from UNAVCO in BINEX and RTCM3 formats along with PPP position estimates generated for each site and broadcast in the NMEA format. We present an update on our activities of integrating NOTA GNSS stations into the ShakeAlert Earthquake Early Warning System that is being developed for California, Oregon, and Washington. Robust GPS/GNSS real-time streams are essential for any type of GNSS-supported early warning application. For Earthquake Early Warning, high data completeness are needed to estimate peak ground displacement, location, including depth, and magnitude of an event, whereas low data latencies facilitate a rapid warning for a larger area. UNAVCO is working with the USGS and other partners to collocate seismic instruments with 54 NOTA stations. In addition another 83 stations west of the I-5 corridor are proposed to be upgraded to full GNSS during FY19/20. Providing complete, low-latency real-time streams from the site to the processing center hinges critically on operational equipment and reliable telemetry. In order to maintain this we rely on a comprehensive state-of-health monitoring system that allows us to optimize station maintenance activities and equipment upgrades, prevent data loss and telemetry outages, and optimize quality.

Presenting Author: Ken Austin

Authors