Wave Imprint

The NASA/CNES SWOT satellite captured the first-ever 2D map of a major tsunami crossing the Pacific — the M8.8 Kamchatka event — and found short-wavelength dispersive wave trains near the source that overturn 30 years of tsunami modeling.

magnitude

M8.8 Mw

wave speed

~700 km/h

dispersive zone

~1,000 km

model

Classic

Detection pipeline

The science: NASA and CNES's SWOT (Surface Water and Ocean Topography) satellite produces wide-swath 2D maps of sea surface height — not just isolated point measurements from tide gauges. When a magnitude 8.8 earthquake struck off Russia's Kamchatka Peninsula in July 2025, SWOT captured the resulting tsunami as it crossed the Pacific. Within roughly 1,000 km of the epicenter, it detected a complex train of short-wavelength "dispersive" waves traveling at different speeds — entirely absent from classical tsunami models, which assumed a single coherent long-wavelength wavefront. These near-source dispersive trains indicate far greater wave complexity arriving at shore than previous models predicted, with significant implications for coastal hazard assessment and early-warning systems worldwide.