New tsunami alert system tested in Portugal
A new tsunami alert system developed by the JRC was tested in Setubal, Portugal, today. The experiment confirmed the effectiveness of using a sea level measurement device to trigger automatic alerts. This new system could be used to detect any kind of tsunami before they reach the sea shore, and issue automatic warnings to populations at risk in order to facilitate timely evacuations.
The experimental alert system being tested in Setubal consists of a digital panel and a sea level measurement device. The digital panel, equipped with data receivers, a siren and loudspeakers, has been placed in the Albarquel Park, by the sea. The sea level measurement device is positioned 3 kilometres from the digital panel along Setubal’s coast. During the test conducted on 2 October 2014, a measurement device was placed inside a mechanical simulator, which simulates a rise in the sea level corresponding to a tsunami wave. When the measurement device detects a significant rise in the sea level, it transmits a signal to the digital panel, which then alerts people present in the park via the digital panel, the loudspeakers and the siren.
The experiment confirmed that the real time analysis and transmission of the signal from the measurement device to the alert panel is reliable. It also demonstrated that sea level measurement can be efficient as a triggering mechanism for a tsunami alert device. Increasing the distance between the measurement device and the sea shore would increase the lead time before the arrival of the wave and thus provide more time to evacuate.
The alert device can also be activated manually, if necessary, or in cases of tsunamis caused by earthquakes, the panel can be automatically activated using JRC software, which estimates the wave height and travel time on the basis of the epicentre and magnitude of the earthquake. Connecting the alert device with local sea level measurement systems will allow automatic activation of the alarm also in case of dangerous waves of non-seismic origin, created by undersea landslides or collapsing volcanoes. In such cases, existing alert systems based on seismic signals wouldn’t be able to send a prior warning. The decision to allow automatic or manual alerting is to be assumed by the local authorities in charge of people evacuation.
The experiment is part of a European research activity which studies new advanced methods to improve disaster alerting mechanisms and to shorten the transmission time of alerts. The JRC is conducting the experiment in close collaboration with the Portuguese Institute of Sea and Atmosphere (IPMA).