See NASA’s GUARDIAN Catch a Tsunami

This animation shows how, following a massive earthquake off Russia on July 29, 2025, GUARDIAN flagged an incoming wave west of Hawaii some 32 minutes before it made landfall and was detected by tide gauges (shown in blue).

A new data visualization illustrates how an experimental NASA technology can provide extra lead time to communities in the path of a tsunami. Called GUARDIAN (GNSS Upper Atmospheric Real-time Disaster Information and Alert Network), the software detects slight distortions in satellite navigation signals to spot hazards on the move.

For the next several hours, signs of the tsunami were picked up by GUARDIAN across the Pacific Ocean in near real time. The system flagged an incoming wave off the coast of Kauai some 32 minutes before it made landfall and was detected by tide gauges (shown in blue).