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Predicting Great Lakes Meteotsunamis with Better Modeling | Michigan Tech News – Michigan Tech News

Weather-induced tsunami events can cause water levels to rise two meters in 10 minutes.
A new, improved forecasting model will help Great Lakes communities prepare and respond.

Though some might consider the Great Lakes an unlikely place for tsunamis to occur,
meteorological events can cause incredibly rapid lake level rises, known as meteotsunamis.
And until now, Great Lakes coastal forecasting models have not been precise enough
to accurately predict these events. 

Michigan Technological University’s Pengfei Xue, along with collaborators at Colorado School of Mines, the National Oceanic and Atmospheric
Administration (NOAA) and Argonne National Laboratory, has developed a higher-resolution
model that refines the model grid from 500 meters down to just 10 meters, providing
much more accurate depictions of modeled events. Additionally, the improved model’s
attributes allow it to simulate key dynamic processes to predict water movement over
coastal infrastructure (such as breakwaters) and during coastal inundation.

The water flood map simulated the 2018 Ludington meteotsunami depicting the control
run (top), LL case (middle), and the difference in the flood area (bottom) at peak
water level timestamp. Graphic credit: Pengfei Xue

“There are essential hydrodynamic processes need to be resolved in our models of the
Great Lakes to be able to simulate and predict meteotsunami-induced coastal inundations,”
said Xue, an expert in developing numerical models to study hydrodynamic, climate
and environmental problems in the Great Lakes. “Working with NOAA, we have developed
a new model that can resolve some of the key processes including wetting and drying
in low-lying zones, as well as submerging and overtopping of coastal infrastructures.
This model aims to forecast the realistic hazards associated with meteotsunami events,
and allows us to assess and explain meteotsunami impacts on the Great Lakes coasts.”

Rising Waters and Model Effectiveness

In April 2018, a meteotsunami hit the community of Ludington on the western coast
of Michigan’s Lower Peninsula. Harbor breakwaters were overtopped and flood waters
inundated the shoreline and nearby city streets.

At the time, computer model grids lacked the precision to truly forecast the water
level rise, and since the Ludington station — a stilling well that measures water
level fluctuations, including those induced by meteotsunamis — is inside the harbor,
it also underestimated the full extent of the meteotsunami due to wave energy dissipation.
Harbors by their nature are sheltering, whether because of physical features like
rocks or cliffs or because of rapidly decreasing water depth.

Today, computational advances have allowed researchers to improve and validate modeling
like never before.

“Up until now, our models of the Great Lakes allowed us to simulate and test for meteotsunami
formation in the lakes, giving us information on timing, location and wave height
at the coast,” said Eric Anderson, an associate professor at Colorado School of Mines collaborating with Xue on the
project. “However, we weren’t able to properly describe the true hazards generated
as those waves propagate into the coast. By extending and enhancing these models,
we have demonstrated the differences between what might be predicted along the open
coast of the lake and what might be measured or experienced within harbors and coastal
communities.”

Under climate change, there will be more severe storms, winds and weather systems
for the Great Lakes region. Coastal hazards will become more severe, especially coastal
flooding. Better modeling will help coastal planners identify high-risk regions and
implement preparatory measures at a local scale.

Michigan Technological University is a public research university founded in 1885 in Houghton, Michigan, and is home to more than 7,000 students from 55 countries around the world. Consistently ranked among the best universities in the country for return on investment, the University offers more than 125 undergraduate and graduate degree programs in science and technology, engineering, computing, forestry, business and economics, health professions, humanities, mathematics, social sciences, and the arts. The rural campus is situated just miles from Lake Superior in Michigan’s Upper Peninsula, offering year-round opportunities for outdoor adventure.

Source: https://www.mtu.edu/news/2021/12/predicting-great-lakes-meteotsunamis-with-better-modeling.html

Author: News tech