Roger, J.H.M.; Taylor-Offord, S. 2026 Review on Tsunami-Monitoring technologies. Lower Hutt, NZ.: Earth Sciences New Zealand. GNS Science report 2026/13. 25 p.; doi: 10.21420/A3VZ-7H85
Abstract
Tsunami hazard can be widespread and have a variety of origins; notably earthquakes (most common), landslides and volcanic eruptions. Monitoring technologies have been designed and deployed to quickly assess the generation of a tsunami, its propagation towards populated coasts and its landfall. The most common devices used to monitor tsunami sources are seismometers, accelerometers and GNSS stations, which enable the location, magnitude and mechanism of potentially tsunamigenic earthquakes to be characterised. These pair with sea-level monitoring capabilities, such as DART systems and coastal gauges, to directly sense ocean-surface fluctuations associated with tsunami. Although these technologies are useful and robust, each has limitations that restrict their utility and breadth of installation, and some carry significant costs that can make their use impractical. The last two decades have seen new technologies progressively emerging to try to fill these gaps, such as commercial submarine cables equipped with geohazards-dedicated SMART nodes; distributed (DAS) or integrated (optical interferometry) techniques, using optical fibre physical properties and behaviours; satellite altimetry; onshore beam radar; ionospheric disturbances monitoring using GNSS networks; and hydrophones for monitoring non-earthquake sources of tsunami. This report aims to highlight the advantages and drawbacks of these new capabilities and their potential future evolution into tsunami early-warning and data-collection capabilities usable for Aotearoa New Zealand. To provide a baseline for comparison, the contribution of those tsunami-monitoring technologies currently in use by GeoNet are also described, including comment on how these also might be improved to support tsunami early-warning capabilities (auth)
