Publication Date:
2023-08-31
Description:
Natural hazards (earthquakes, tsunamis, volcanic eruptions, etc.) have devastating human and economic consequences. Their early detection and characterization lead to timely evacuations, which are critical for significantly reducing casualties and economic cost. However, traditional early warning systems (EWS) are limited by inherent challenges. We present two novel GNSS-based methods that are viable augmentations to EWSs. The first, developed at Central Washington University, monitors earthquakes and tsunamis globally, based on low-latency in-situ measurements from ~1800 globally-distributed receivers. The system can rapidly characterize moment release, as ruptures unfold. Position time series are continuously streamed as local 3D coordinates into monitoring algorithms, and also broadcast for third-party use. The system’s average latency is ~0.5 seconds, and its average position variance remains below 8 cm. This system captured the 2019 M7.1 Ridgecrest earthquake on 12 nearby stations within 22 seconds after onset; the system’s estimates of co-seismic deformation were within 10% of the post-processed “true” values. In addition, another remote sensing technique leverages ionospheric total electron content (TEC) measurements. Indeed, through mechanical coupling, large air and ground perturbations at the Earth’s surface propagate up as low-frequency atmospheric waves. Eventually disrupting the ionosphere, those waves can be observed through ground-based GNSS measurements. In particular, we present the GUARDIAN system, developed at JPL (https://doi.org/10.1007/s10291-022-01365-6), which runs in near-real-time (latency 〈 5 minutes) using multi-GNSS data from 80 stations from JPL’s GDGPS network around the Pacific Ocean. GUARDIAN outputs TEC time series to a user-friendly public website, and are routinely validated against traditional ionospheric post-processing techniques.
Language:
English
Type:
info:eu-repo/semantics/conferenceObject
Permalink