麻豆淫院

Landslide-generated tsunamis pose a serious risk to coastal communities, particularly within narrow fjords where tall cliffs can trap and amplify waves. Scientists rely heavily on earthquake-based observation systems to issue tsunami warnings, but these methods don't always capture localized ground movement caused by landslides.

Now, for the first time, scientists have detected tsunami waves caused by a landslide using data from a ship's satellite receiver. The CIRES and CU Boulder-led research, in Geophysical Research Letters, shows the potential for an approach to improving tsunami detection and warning, providing lifesaving information to coastal communities.

"Landslides into water can produce a tsunami, and some of them can be quite large and destructive," said CIRES Fellow Anne Sheehan, a professor of Geological Sciences at CU Boulder and co-author of the study. "Scientists have captured larger, earthquake-induced tsunamis using ship navigation systems. Our team had equipment in the right place at the right time to show this method also works for landslide-generated tsunamis."

On May 8, 2022, a landslide near the port city of Seward, Alaska, sent debris tumbling into Resurrection Bay, creating a series of small tsunami waves. The R/V Sikuliaq, a research ship owned by the National Science Foundation and operated by the University of Alaska Fairbanks, was moored 650 meters (0.4 miles) away. Luckily, it was equipped with an external Global Navigation Satellite System (GNSS) receiver previously installed by Ethan Roth, the ship's science operations manager and co-author of the study.

"I actually happened to be in Alaska at that time, retrieving seismometers from another study," Sheehan said. "I decided to go visit the Sikuliaq, and it turned out that there had been a landslide that happened a day or two before. One of the crew members filmed it, and we were like, 'wow,' this is a great signal to try to find in the data."

Adam Manaster, then a graduate student working in Sheehan's geophysics research group at CIRES and CU Boulder, took the lead on the project. The research team also included scientists from the USGS and the University of Alaska Fairbanks.

The team used data from the ship's external GNSS receiver and open-source software to calculate changes in the vertical position of the R/V Sikuliaq down to the centimeter level. They created a time series showing the ship's height before, during, and after the landslide.

The researchers then compared the data to a landslide-tsunami model, which simulated the generation and movement of tsunami waves from the shoreline to the ship. Their results show that the ship's vertical movement was consistent with the event, confirming the first detection of a landslide-generated tsunami from a ship's satellite navigation system.

"This research proves that we can utilize ships to constrain the timing and extent of these landslide tsunami events," Manaster said. "If we process the data fast enough, warnings can be sent out to those in the affected area so they can evacuate and get out of harm's way."

The work builds upon previous CIRES-led , which demonstrated how GPS data from commercial shipping vessels could be used to improve tsunami early warning systems.

"The science shows that this approach works," Sheehan said. "So many ships now have real-time GPS, but if we want to implement it on a larger scale, we need to collaborate with the shipping industry to make the onboard data accessible to scientists."