A. Realita, M.N. Fahmi, T. Prastowo, N.M.A.S.M. Tika, Madlazim
On 15 January 2022, an explosive eruption of Hunga Tonga-Hunga Ha’apai (HTHH) submarine volcano tremendously occurred in the southern Pacific. This released a huge amount of energy into global atmosphere, generated propagating atmospheric disturbances at large scales and in turn induced a fast-travelling tsunami wave with a phase speed higher than a typical value for a conventional tsunami of 800 kmh-1. In response to this extreme occurrence, we examined tsunami propagation from the 2022 HTHH case, particularly in the far-field observations where atmospheric effects mostly influence on the propagation. Therefore, this study aims to determine the speed of a leading meteo-tsunami propagating on the sea surface detected by field instrument operated by National Oceanic and Atmospheric Administration. The methods involved tsunami datasets extraction and examination, and the corresponding analysis. The results showed that tsunamis travel with different rates in near- and far-field regimes. For 100 min or approximately 1300 km away from the epicentre, the wave propagates at a typical speed of 800 kmh-1 or about 220 ms-1. In the far-field, the wave is accelerated up to a value similar to the Lamb wave speed of 1110 ± 10 kmh-1 that is equal to 308 ± 3 ms-1. The current research finding implies for a better prediction of tsunami travel time and hence arrival time for minimising risk at the cost of early evacuation whenever a meteo-tsunami is generated owing to an extreme eruptive event. © 2024 Institute of Physics Publishing. All rights reserved.
Department of Physics, Universitas Negeri Surabaya, Surabaya, Indonesia
