A line of storms raced from Wisconsin toward southwestern Michigan and northeast Indiana faster than an express CTA train. In Michigan City, Ind. Once the squall crossed over onto land, the winds died down on Lake Michigan, allowing the wave to double back across the lake with little resistance. About an hour later in Chicago, where the weather was fair and the waters were calm, hundreds of people along the lakefront were caught off-guard by a roughly foot wall of water. The water just rose — straight up.
The tragedy underscores the danger for cities along western Lake Michigan where the weather can be fine, but a bygone or faraway weather system could produce a meteotsunami. The number of meteotsunami episodes could grow in the future as climate change creates conditions favorable for more thunderstorms capable of producing large wave fronts. But even right now, during this current period of high lake levels , the swift waves have the potential to be more menacing. While the meteotsunami is perhaps the most infamous example of the monumental size and force these waves can reach, much smaller meteotsunamis have proved capable of being just as deadly.
On July 4, , a formation of storm cells unleashed gusts up to 50 mph on Lake Michigan, blowing through southwestern Michigan in 20 minutes, creating a 1-foot meteotsunami across Lake Michigan.
Hours later, once the ominous storm clouds passed and the sun broke through, beachgoers descended on the lakefront. One by one, swimmers began to disappear. Seven people, all with Chicago ties, died within four hours, including three members of a South Side congregation of Jehovah's Witnesses who drowned at Warren Dunes State Park.
Researchers say when the meteotsunami rolled away from the shoreline and caromed to the other side of the lake, it created a strong undercurrent that began plucking beachgoers from shallow water.
A study published earlier this year re-examined 94 fatalities and rescues involving rip currents at Lake Michigan beaches over 15 years. Sixteen percent of the deaths and 12 percent of rescues occurred on the same day as a meteotsunami, suggesting a connection between the two beach hazards.
Director Dave Benjamin acknowledges the threat posed by meteotsunamis, but he said only one-third of the drownings in the region are caused by dangerous waves or currents. To him, it speaks to a larger need for overall water safety education. Tsunamis in general have been portrayed in illustrations as lofty, curling waves poised to tumble atop anything in their path. In reality, historical accounts describe a much stealthier encounter.
Though Lake Michigan experiences the most meteotsunamis of any of the Great Lakes with an average of 51 events annually, other shorelines across the region are not immune. Tsunamis on the Great Lakes might sound as unlikely as major earthquakes in Detroit. But Great Lakes tsunamis are a real phenomenon that at times have proven deadly. Some of the world's leading experts on tsunamis met in Ann Arbor last year to discuss meteotsunamis on the Great Lakes and the potential development of an early-warning system for them.
Also on Freep. Is Detroit's sewage plant at risk for a power failure? State plan to combat algae in Lake Erie needs work, critics say. Tsunamis in our oceans are typically brought about by earthquakes — a sudden, upward thrusting of the Earth's crust rapidly displacing massive amounts of water, leading to a large, long wave that builds in intensity as it crosses the ocean. Meteotsunamis work in much the same way on the Great Lakes, but the displaced water that starts them is from sudden, very intense storms on the lakes, causing winds or barometric pressure to push down on the water.
This article was published by Michigan State University Extension. Are there tsunamis in the Great Lakes? Did you find this article useful? Please tell us why Submit. Fish Notes: A seasonal e-newsletter about fish and fishing in West Michigan. Subscribe Here. Learn about Great Lakes ice cover, new invasive species, and how poop-sniffing dogs help beaches.
Teachers bring Great Lakes science explorations back to school. Exploring integrated learning through place-based stewardship education. Au Gres develops a new vision for a premier waterfront. Impact: Flooding causes widespread property damage while polluting rivers and lakes with sewage and surface runoff, Malec-McKenna notes. Solutions: Malec-McKenna says city planners and developers can create more water-absorbent surfaces, like permeable alleys , that can hold water instead of sending it into sewers.
City officials can use places like parks to hold water in restored wetlands and even reservoirs built beneath the park. When it comes to city residents, she recommends swapping plants with shallow roots, like grass, with deeper-rooted plants to create more water-absorbent landscapes. Chicagoans can also help reduce flooding by connecting gutters to rain barrels and limiting their water use — showers, dishwasher and washing machines — during storms.
That excess water can further overload the sewers. The extreme temperatures and rainfall brought on by climate change will create more dry spells, Malec-McKenna says. Impact: Droughts will throw the local ecosystem out of balance, Malec-McKenna says. It will hurt crops and add stress to trees and other plants that birds and insects rely on for survival. Droughts could mean less food, reduced animal populations, and the proliferation of invasive species.
Malec-McKenna says climate change will create more extreme temperatures, and the depletion of the ozone layer will reduce protection from the sun.
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