Overview
- The peer-reviewed Science study reports that the NASA/CNES SWOT satellite flew over the tsunami about 70 minutes after the July 2025 magnitude 8.8 Kamchatka earthquake and mapped the full two-dimensional wavefield with centimeter precision.
- SWOT resolved a train of short, slower “dispersive” waves trailing the leading front within roughly 1,000 kilometers of the source, revealing the waves’ shape, direction, and spacing.
- Analysis of these trailing waves indicates additional earthquake slip shallower than 10 kilometers near the trench, with an along-strike centroid between 49.5°N and 52.5°N.
- Five nearby DART deep-ocean buoys captured only the leading surge—topped by a 1.32-meter crest-to-trough reading—showing why sparse sensors can miss short-wavelength signals that SWOT can see.
- Processed satellite data enabled forward simulations that reproduced the observed wavefield, a result the authors say can improve tsunami source models, guide future warning systems, and build on similar SWOT detections in 2023 and May 2025.