Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: Journal of Geophysical Research: Oceans
In a new study, Zaytsev et al. [2024] analyzed sea level records along the coasts of the Americas, enabling them to identify two distinct types of tsunami waves corresponding to “atmospheric” and “oceanic” sources from the 2022 Tonga volcanic eruption. The atmospherically-generated waves are sea level oscillations exciting by intense Lamb waves in the atmosphere that propagated over the globe with the speed of sound. The oceanic tsunamis are waves produced directly in the source area by the volcanic eruption.
Using frequency-time analysis, the main criterion used to recognize and separate these two types of waves was the wave speed difference, where the atmospheric tsunami (about 315 m/s) moved through the ocean approximately 1.5 times faster than oceanic long waves (about 200 m/s). Consequently, the atmospherically-generated tsunamis arrived at the Pacific coasts of Americas about 4–5 hours earlier than the oceanic waves. The results reveal important differences in height and arrival time for each of these types of waves, at both open ocean and coastal observation sites.
Citation: Zaytsev, O., Rabinovich, A. B., & Thomson, R. E. (2024). The 2022 Tonga tsunami on the Pacific and Atlantic coasts of the Americas. Journal of Geophysical Research: Oceans, 129, e2024JC020926. https://doi.org/10.1029/2024JC020926
—Ryan P. Mulligan, Editor, JGR: Oceans