Limited impact of the 2025 Kamchatka tsunami explained by the complex seismic rupture

Abstract The great 29 th of July 2025 megathrust earthquake of magnitude 8.8, which occurred near the Kamchatka Peninsula, Russia, generated a local tsunami comparable to that of its larger 1952 predecessor, which, in contrast, caused a larger tsunami along the far-field Pacific shorelines. The 2025 tsunami was also smaller than anticipated by the life-saving tsunami warning issued for the far-field Pacific shorelines. By jointly inverting SWOT and DART tsunami data, InSAR and GNSS data, here we show that the 2025 earthquake rupture occurred within or adjacent to the 1952 source area, with an uncertain degree of overlap. We also show that a smaller tsunami potential energy due to earthquake magnitude and relatively deep slip explains the moderate far-field impact. Conversely, some shallow displacement that reaches the trench explains the enhanced local runup, comparable to the 1952 runup, despite the smaller magnitude of the 2025 earthquake. Our findings are supported by comparisons with previous tsunamis (2010 Maule, Chile, and 2005 Nias, Indonesia).