Imagine a devastating hurricane headed toward the U.S. coast.
Winds are blowing at more than 100 mph, the skies are darkening and rain is beginning to fall, first as a steady downpour and then coming in sheets.
As the storm moves even closer to landfall, the ocean churns record waves and a storm surge is pushed toward shore.
Now, imagine throwing in an earthquake for good measure.
That is the nightmare scenario scientists say is actually all too real, according to a study in the journal Geophysical Research Letters.
The combination of a strong hurricane and an earthquake generating from the seabed even has a cool made-for-TV movie moniker – stormquakes.
Something from the study that may surprise people is that the quakes are fairly common. They go unnoticed because they occur during a land-falling hurricane.
"This is the last thing you need to worry about," Wenyuan Fan, a Florida State University seismologist who was the study's lead author, told The Associated Press.
Here is what happens in a stormquake, according to Fan.
While the dynamics of a hurricane produce massive waves in the open ocean, they also spark other types of waves. In certain place where there is a large continental shelf near shallow flat land, those waves can interact with the seafloor to produce an earthquake.
According to the study, a little more than 14,000 stormquakes occurred between September 2006 and February 2015. Those quakes happened in the Gulf of Mexico and the Atlantic off Florida, New England, Nova Scotia, Newfoundland and Labrador. They also tend to happen in the Pacific off the coast of British Columbia.
According to the study, the shaking of the seafloor during hurricanes and nor’easters can rumble like a magnitude 3.5 earthquake and last for days.
Ocean-generated seismic waves show up on U.S. Geological Survey instruments, “but in our mission of looking for earthquakes, these waves are considered background noise,” seismologist Paul Earle, of the USGS National Earthquake Information Center in Golden, Colo, told The Associated Press.