New research has found the Great Lakes may have a type of tsunami after all. They are not tsunamis caused by earthquakes. These tsunamis are caused by organized areas of thunderstorms.

The type of tsunami is called a meteotsunami, meaning a tsunami caused by meteorological conditions. While the waves are not as big as ocean tsunamis caused by earthquakes, researchers have found an instance when the tsunami on a Great Lake was nine feet high.

Adam Bechle, post doctoral research associate at the University of Wisconsin - Madison, worked with Chin Wu - University of Wisconsin - Madison, David Kristovich - Prairie Research Institute, and Eric Anderson from Great Lakes Environmental Research Laboratory on the research.

They describe a meteotsunami on the Great Lakes as a rapidly moving wave. The wave can be generated by either high wind speeds, rapidly changing air pressure, or both.

The typical situations leading to the formation of a meteotsunami on the Great Lakes are either a linear formation of thunderstorms, or an organized complex of long lasting thunderstorms.

The biggest meteotsunami found in looking at modern data back to 1995 hit the Lake Michigan shoreline at White Lake Harbor, 45 miles south of Ludington, MI. This occurred with the massive severe weather event on May 31, 1998.

Here is the radar loop from that severe weather situation on May 31, 1998:

While you may think thunderstorms would have to occur for a meteotsunami on the Great Lakes, this is not always the case. A rapid change in air pressure under non-stormy conditions can also create a meteotsunami. Bechle called this kind of tsunami a "sneaky" tsunami, as you probably wouldn't be on the lookout for it.

The most deadly example of a meteotsunami on the Great Lakes occurred in Chicago in 1954. Chicago was hit by a storm. The west wind didn't generate a big wave at Chicago, but it did make a big wave out in Lake Michigan. This wave hit the east shore of Lake Michigan and then bounced back to Chicago. People on a pier were knocked into the water, and seven drowned.

The researchers found these meteotsunamis form when the storm moves at the same speed and direction as the wave. The wind keeps transferring energy into the wave, and causes the wave to increase in size.

Many seiches may have been tsunamis

The Great Lakes had long been know to have seiches (pronounced say-sh). Seiches are a long duration rising and falling of the water, usually taking several hours. Meteotsunamis happen in a matter of minutes.

In fact, the researchers now say the seiche I reported on here at MLive on Sept, 4, 2014 was instead a meteotsunami.

Many of the reported seiches over the years may now be considered meteotsunamis. Researchers say they don't have plans right now to go back into history and reclassify these seiches.

Big waves produced two deadly incidents in Holland and Grand Haven in the early 1900s.

• Fourth of July, 1929: 10 died in Grand Haven when a 20 foot wave hit and buried the pier, and strong rip currents carried people away from shore. The wave came after an early morning storm.

• July 13, 1938. Five died when a 10-foot wave hit during a calm day on at Holland State Park. In the past, researchers have said that water pushed toward Wisconsin after two days of powerful east winds barreled back westward, sweeping people off the Holland beach, pier and boats.

The term meteotsunami first originated in the Mediterranean Sea, where these big waves are common. There the meteotsunamis can grow up to 27 feet tall.

Have you ever experienced a meteotsunami? Please share your story or pictures below.

MLive Chief Meteorologist Mark Torregrossa has been forecasting Michigan weather for more than 25 years. He's been chief meteorologist at three television news stations in Michigan, and he's an avid gardener and hunter. Email him at mtorregr@mlive.com and find him on Facebook at facebook.com/mark.torregrossa and Twitter @weathermanmark