Detection of Tsunami Waves with GNSS Reflections

Abstract:

The value of ground-based GNSS sensors for tsunami warning is well understood. To support the inclusion of three-dimensional GNSS positions in both tsunami and earthquake warning systems, significant effort has been made to add real-time telemetry and to test/automate real-time GNSS data analysis systems. To date the potential of these same GNSS data streams for measuring the ocean surface height directly has not been examined. Here I will address the potential of ground-based GNSS reflectometry to measure tsunami waves in near real-time. I will summarize the limiting errors in the GNSS-reflection method for tsunami warnings and explain what determines how quickly the tsunami waves can be measured. In addition to showing GPS surface heights measured during a tsunami, I will explain how upgrading aging GPS systems to modern multi-GNSS sensing receivers would greatly enhance tsunami warnings.