#meteotsunami

I remember as a kid being told about the “seiche” in Lake Michigan that drowned a lot of people who were on shore in Chicago. I was told to think of a seiche like a the water in big bucket or a toilet bowl: the water sloshes from side to side until it settles down, and when those waves strike the shores (the sides of the bucket or the sides of the toilet bowl), they’re big waves and they bounce back and forth. This story in the Chicago Tribune explains the science better, and informs us that the Great Lakes experience these “meteotsunamis” frequently.

Excerpt:

Unlike typical lake waves that roll by every three to five seconds, meteotsunamis can last for two minutes to up to two hours, dramatically raising localized lake levels and spawning dangerous rip currents that can carry swimmers offshore. Although many of these weather-generated waves are often modest in height — sometimes only standing 1 or 2 feet tall — their longevity can be formidable. But the 1954 wave, set in motion by a dramatic rise in atmospheric pressure and straight-line winds, was colossal, roiling the shoreline for 15 minutes, scientists say.

While these waves previously were thought to be rare, recent studies by the University of Wisconsin at Madison revealed they are quite common and sometimes responsible for a water hazard more familiar to Chicagoans — rip currents. More than 100 meteotsunamis occur across the Great Lakes each year, many prompting rescue efforts or causing significant damage to coastal infrastructure.

Not only has the threat posed by meteotsunamis been seriously underestimated, according to scientists, but the bulk of these waves occur in the late spring and early summer, overlapping with much of beach season.

In 1935, Japanese professor Takaharu Nomitsu was the first to describe “tsunamis of atmospheric origin,” waves that were triggered by weather systems rather than earthquakes like true tsunamis.

Meteotsunamis are driven by air-pressure disturbances like a thunderstorm, squall or storm front. The wind from the disturbance pushes down and across the water causing a wave that moves toward the shore. The wave is amplified in shallower parts of the lake and can bounce off wide parts of shoreline. This animation shows how the deadly 1954 meteotsunami moved across Lake Michigan for more than five hours. Colors show changing lake levels.

La secuencia de retirada abrupta del mar y olas violentas en la Costa Atlántica es compatible con un meteotsunami, un fenómeno oceánico poco frecuente y difícil de predecir. Un joven de aproximadamente 30 años murió este lunes luego de ser arrastrado por una ola de gran magnitud que impactó de manera repentina sobre la playa de Santa Clara del Mar, en el partido bonaerense de Mar Chiquita.…

YER ÇEKİMİ DALGALARININ SEBEP OLDUĞU TSUNAMİLER KEŞFEDİLDİ

ABD’nin Michigan eyaletinde meydana gelen tsunamiye ilişkin veriler, iklim değişikliğinin neden olduğu ve bugüne kadar fark edilmeyen bir olguyu ortaya çıkardı. 13 Nisan 2018 günü Michigan Gölü’nün doğu kıyısında büyük bir su kabartısı ortaya çıktı. Bu bir tsunamiydi ve tipik bir biçimde devasa dalgalarla ilişkilendirilen herhangi bir fay hattından çok uzaktaydı. Bu bir ‘meteotsunamiydi’,…