Destructive Potential of Planetary Meteotsunami Waves beyond the Hunga Tonga–Hunga Ha‘apai Volcano Eruption

Abstract

Worldwide tsunamis driven by atmospheric waves – or planetary meteotsunami waves – are extremely rare events. They mostly occur during supervolcano explosions or asteroid impacts capable to generate atmospheric acoustic-gravity waves including the Lamb waves that can circle the globe multiple times. Recently, such ocean waves have been globally recorded after the Hunga Tonga–Hunga Ha’apai volcano eruption on 15 January 2022, but did not pose any serious danger to the coastal communities. However, this study highlights that the mostly ignored destructive potential of planetary meteotsunami waves can be compared to the well-studied tsunami hazards. In practice, several process-oriented numerical experiments are designed to force a global ocean model with the realistic atmospheric response to the Hunga Tonga–Hunga Ha’apai event rescaled in speed and amplitude. These simulations demonstrate that the meteotsunami surges can be higher than 1 m (and up to 10 m) along more than 7 % of the world coastlines. Planetary meteotsunami waves thus have the potential to cause serious coastal damages and even human casualties during volcanic explosions or asteroid impacts either releasing intense acoustic energy or producing internal atmospheric gravity waves triggering the deep-ocean Proudman resonance at a speed of ~212 m/s. Based on records of catastrophic events in the Earth’s history, both scenarios are found to be realistic and, consequently, the global meteotsunami hazards should now be properly assessed to prepare for the next big volcanic eruption or asteroid impact even occurring inland.

Global Winds Shape Planetary‐Scale Lamb Waves

“…In 2022, tsunami heights of over a meter were not only observed in the Pacific Ocean, where the volcanic eruption took place, but also in the Atlantic Ocean near the antipode (Carvajal et al., 2022). Since atmospheric waves generated by volcanic explosions (or even asteroid collisions) have the potential to produce worldwide tsunamis comparable to others produced by traditional tsunamigenic mechanisms, modeling these waves accurately and quickly is critically important for early warnings and hazard assessments (Denamiel et al., 2023).…”

“…In 2022, tsunami heights of over a meter were not only observed in the Pacific Ocean, where the volcanic eruption took place, but also in the Atlantic Ocean near the antipode (Carvajal et al, 2022). Since atmospheric waves generated by volcanic explosions (or even asteroid collisions) have the potential to produce worldwide tsunamis comparable to others produced by traditional tsunamigenic mechanisms, modeling these waves accurately and quickly is critically important for early warnings and hazard assessments (Denamiel et al, 2023).In both the 1883 and 2022 eruptions, the largest far field pressure variations came from the Lamb wave, which travels near the speed of sound and has maximum amplitude at the Earth's surface. Several troposphere properties can modify the propagation of Lamb waves.…”

Volcanic Eruption Triggers a Rare Meteotsunami in the Indian Ocean

“…High-frequency variability contributes to up to 50% of sea-level extremes in some low tidal regimes (Vilibić & Šepić, 2019). According to numerical experiments conducted by Denamiel et al (2023), about 7% of the world's coastline is susceptible to meteotsunami surges (1-10 m), with the potential to cause significant damage and even fatalities. However, this variability is often not considered in extreme sea-level studies.…”

Global water level variability observed after the Hunga Tonga-Hunga Ha'apai volcanic tsunami of 2022

“…Values at the larger end of this range were mainly seen at coastal locations; island locations typically had β < 5, with only a few exceptions (e.g., Hawai'i and Naha). The reasons why certain regions exhibited a larger amplification (e.g., β) than others, and the possible role of bathymetry, remain to be understood, e.g., through model studies like Denamiel et al (2023). It seems likely, however, that locations with an ocean trench between the source and the coastal station are at particular risk; this is typical for much of the Pacific "Ring of Fire", as conceptualized in Fig.…”