Ripepe M, Lacanna G
Dipartimento di Scienze della Terra, Università di Firenze, 50121, Florence, Italy.
Nat Commun. 2024 Feb 27;15(1):1802. doi: 10.1038/s41467-024-45937-1.
Volcano sector collapse and pyroclastic density currents are common phenomena on active volcanoes and potentially a fatal source of tsunami waves which constitute a serious hazard for local as well as distant coastal population. Several examples in recent history, warn us on the urgent need to improve our mitigation counter-actions when tsunamis have volcanic origin. However, instrumental record of tsunami generated by mass movement along a volcano flank are still rare and not well understood yet. Small tsunamis (≤1 m) induced by pyroclastic density currents associated to violent explosions of Stromboli volcano were recorded in near-source conditions (<1.6 km). We show how tsunami waveform remains unaltered regardless of the two orders of variability in the landslide volume and dynamics. This unprecedented record is also providing the lesson to develop unconventional warning strategies necessary when the tsunamigenic source is expected to be very close (<10 minutes) to densely populated coasts and with a limited time to issue an alert based on simulation of wave propagation and inundation.
火山扇区崩塌和火山碎屑密度流是活火山上的常见现象，并且可能是海啸波的致命来源，这对当地以及遥远的沿海人口构成严重危害。近代的几个例子警示我们，当海啸起源于火山时，迫切需要改进我们的减灾应对措施。然而，由沿火山侧翼的大规模移动引发的海啸的仪器记录仍然很少，并且尚未得到很好的理解。在近源条件下（<1.6公里）记录到了由斯特龙博利火山剧烈爆炸产生的火山碎屑密度流引发的小型海啸（≤1米）。我们展示了无论滑坡体积和动力学的两个变化量级如何，海啸波形都保持不变。这一前所未有的记录也为制定非常规预警策略提供了经验教训，当海啸源预计非常靠近（<10分钟）人口密集的海岸，且基于波浪传播和淹没模拟发布警报的时间有限时，这些策略是必要的。
