Dusek et. al. April 2019. (NOAA) /

South Carolina: Myrtle Beach tops list for number of mini-tsunamis per year, says NOAA

MYRTLE BEACH, S.C. (WPDE) — You've heard of tsunamis - giant powerful ocean waves that pummel coastlines primarily after an earthquake strikes. But have you heard of the little brother known as a meteotsunami?

Unlike tsunamis, which are triggered by seismic activity, meteotsunamis are much more common and can be directly related to differences in air-pressure, typically found associated with fast moving weather events. These can be cold fronts, squall lines, and even tropical cyclones.

According to a new report from NOAA, an average of 25 meteotsunamis hit the East Coast of the United States each year.

Meteotsunamis tend to be much weaker in nature than those triggered by seismic activity. On average, most meteotsunamis see a sea level rise by less than 1.5 feet, and can be considered relatively harmless. Only about one of these meteotsunamis a year will produce a wave that exceeds 2 feet in height, according to the report.

NOAA identified two locations in particular along the East Coast that have observed the greatest number of events. Myrtle Beach, which saw a total of 148 events since record keeping began in 1996, and Duck, North Carolina, which has seen 130 events. That equates to about 7.2 meteotsunamis a year for Myrtle Beach, and 6.0 a year for Duck.

These events are most common during the summer months, for the East Coast, because thunderstorms become more common during these months. Thunderstorms are a very effective producer of needed atmospheric conditions for meteotsunamis to occur.

So what's next? NOAA's Great Lakes Environmental Research Laboratory is working on developing a warning system for all of the Great Lakes region.

Along the East and Gulf Coasts, the National Weather Service is working on developing a system to deliver accurate and timely alerts to the public when these events are detected by their vast array of deep-ocean pressure sensors. This should help provide more timely alerts to coastal residents for expected water rises.

See WPDE article . . .