What earthquake sensors can tell us about hurricanes
A new way to measure hurricanes using earthquake-monitoring equipment could improve storm forecasting, support public safety, and enhance understanding of Earth’s atmosphere
image:
A satellite image of Hurricane Isaac in 2012 as it made landfall on the Louisiana coast. Overlaid on the image is a seismogram showing ground vibrations caused by strong winds before and after the calm eye of the storm passed.
view moreCredit: Satellite image by NOAA National Centers for Environmental Information. Seismogram image by the National Science Foundation’s Seismological Facility for the Advancement of Geoscience. Image provided by Qing Ji.
Stanford researchers have shown that instruments primarily used to understand earthquakes can capture key details about hurricanes, helping meteorologists better predict how storms will evolve and intensify.
A new study published Aug. 6 in Science demonstrates how specialized microphones and seismometers that detect Earth’s movements can reveal the inner workings of hurricanes. The discovery came after Hurricane Isaac barreled onto the Louisiana coast in 2012, passing over areas where geophysicists had installed sensors for another project.
“We’ve found a new and effective way to gather valuable information about hurricanes from seismic and acoustic sensors,” said lead study author Qing Ji, who conducted the research as a PhD student in the lab of Eric Dunham at Stanford University. “The geophysics data can provide a fuller understanding of big storms.”
Since seismometers detect ground movements, they can pinpoint when a hurricane makes landfall, according to the study. By “hearing” low-frequency sound waves inaudible to people, infrasound microphones can also monitor atmospheric pressure – another useful gauge of hurricane conditions over time.
The findings extend beyond hurricanes to other types of storms and atmospheric science more broadly, offering an innovative way to study weather phenomena that produce strong winds.
“You wouldn’t necessarily think there’s an instrumentation connection between the fields of geophysics and atmospheric science, but thanks to this study, we’ve shown that one can inform the other,” said Dunham, the study’s senior author and a professor of geophysics in the Stanford Doerr School of Sustainability.
How hurricanes work
The biggest storms on Earth, hurricanes typically span 300 to 400 miles in diameter, traveling thousands of miles and drawing energy from warm ocean water. A hurricane swirls around a calm, low-pressure eye, which is encircled by a band of intense wind and rain known as the eyewall. Rainbands containing thunderstorms spiral outward from the eyewall like spokes. At landfall, the storms pummel the ground with turbulent winds, rain, and surges of storm tide.
“Hurricanes create pressure fluctuations all over the Earth that are pushing the ground down, pulling it up, and generating seismic signals,” Dunham said.
In the part of the hurricane closest to the ground, wind, heat, and moisture mix together in what’s called the boundary layer. Measuring turbulence in the boundary layer is vital for forecasting storm intensity and behavior, since it’s a key factor in whether a hurricane strengthens or weakens.
To obtain boundary layer data, government agencies fly aircraft into storms to drop parachuted sensors, and assess readings from ocean buoys, wind measurement towers, and radar. These tools have limitations, however. Buoys and wind measurement towers only capture near-surface readings, while radar offers only snapshots of the boundary layer. And the flights can put pilots in danger.
A serendipitous seismic study
As a region that rarely experiences earthquakes, Louisiana had few seismic sensors installed when Hurricane Isaac hit in 2012. But the Category 1 storm happened to pass over stations with seismic sensors and infrasound microphones that had been set up for a National Science Foundation-funded geophysics project mapping Earth’s interior.
“We were certainly a bit lucky that stations were near a hurricane track,” said Ji.
In a prior study of these stations and Hurricane Isaac, Ji and Dunham upended the prevailing assumption that such instrumentation would get overwhelmed by overlapping seismic waves produced over hundreds of kilometers by the storm. They found that rather than a noisy onslaught of far-flung seismic waves, the seismometers were sensitive to the specific boundary layer conditions in their immediate vicinity.
“We saw that what the seismometer measures is dominated by local turbulence at the scale of a few kilometers,” Dunham said. “So that shifted our focus to the boundary layer turbulence processes.”
Adding a second signal
Building on that initial result, Ji and Dunham collaborated with Ipshita Dey (PhD ’24, Earth System Science), who researched boundary layers in the lab of Morgan O’Neill, a former assistant professor of Earth system science at Stanford.
“Qing wanted to see if the signals that he was seeing in the seismic measurements could be from the small-scale features that I was exploring in the boundary layer winds inside hurricanes,” Dey said. “That collaboration took our study to the next level.”
The researchers added readings of low-frequency sound waves inaudible to humans, known as infrasound recordings. The data provided a continuous measurement of turbulent pressure fluctuations in the boundary layer. The combined dataset clearly showed Hurricane Isaac’s calm eye passing over certain stations, preceded and followed by the intense eyewall.
The researchers then compared this dataset with conventionally obtained boundary layer data for the storm and found strong agreement.
“Our study shows the validity of this approach, and the opportunity it offers to use this kind of data in a different way,” Ji said.
The Stanford researchers plan to expand their research to other hurricanes. Hurricane Isaac made landfall as a Category 1 storm. Over about 100 seconds, the hurricane moved the ground a fraction of a millimeter, comparable to a tiny earthquake too weak for people to feel. A stronger storm, such as Category 5 hurricanes Andrew in 1992 and Michael in 2018, should generate a bigger signal and potentially more robust data.
“We can add sensors to make these stations multipurpose, meeting seismic monitoring needs and also providing useful data for atmospheric studies,” Ji said.
Doing so could help researchers around the world better understand hurricanes and other powerful storms, potentially informing decisions around infrastructure, evacuations, public messaging, storm preparations, and other efforts to protect communities.
Funding was provided by the Virgil Kauffman Fellowship.
Journal
Science
Article Title
Turbulent seismoacoustic imprints during a hurricane landfall
Article Publication Date
6-Aug-2026
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