NASA, SWOT satellite capture unprecedented view of giant Pacific Tsunami that affected Russia, Japan; Hawaii; reveal complex wave patterns

NASA and the French space agency's SWOT satellite have captured a rare event, a Pacific-wide Tsunami triggered by an 8.8 magnitude earthquake that struck the Kuril-Kamchatka subduction zone on July 29, 2025. They captured the event, revealing a complex, braided pattern of energy dispersing across hundreds of miles. This challenges traditional assumptions about tsunami behaviour, which is likely a single neat crest racing across the basins. The new experiment suggests current physics models need revision, especially regarding 'non-dispersive' wave packets.

Detailed look at Giant Tsunami

The Surface Water Ocean Topography (SWOT) satellite captured a detailed look at the tsunami, showing a complex pattern of waves dispersing and scattering across the ocean. The image shows a more intricate process, with waves breaking up and dispersing in multiple directions. The SWOT satellite's advanced technology enabled scientists to map a 75-mile-wide swath of sea surface height in a single pass. According to study lead author Angel Ruiz-Angulo, "SWOT data is like a new pair of glasses, allowing us to see the tsunami in unprecedented detail". 

The potential improvements to tsunami forecasting and warning systems provide a better understanding of tsunami behaviour, enabling scientists to develop more accurate models, ultimately saving lives and reducing damage to coastal communities.

Latest study challenges traditional understanding of Tsunami behaviour

NASA and the French space agency CNES launched SWOT in December 2022 to survey surface water around the world.

Researchers Ruiz-Angulo and co-author Charly de Marez had been poring over its data for ocean eddies when the Kamchatka event hit. “We had been analysing SWOT data for over two years, understanding different processes in the ocean like small eddies, never imagining that we would be fortunate enough to capture a tsunami,” they said. The traditional understanding of tsunami behaviour is being turned upside down. For years, scientists believed that massive tsunamis, which span entire ocean basins, behave like shallow-water waves, travelling long distances without breaking apart.