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Tech Rally
02-05-2005, 01:11 PM
Anyone ever hear of this?

'Seiche' phenomenon hits often, sometimes kills
2/01
Thousands of tourists crowded the scenic beach to enjoy a long holiday weekend, unaware of the approaching tidal wave that would sweep them into a deadly natural disaster. That was the scene one month ago, when a killer tsunami raced across the Indian Ocean and killed more than 225,000 people in South Asia.

It also was the scene on July 4, 1929, at Grand Haven State Park, when killer waves swept 10 people to their deaths on one of the deadliest holidays in West Michigan history. The culprit here was not a tsunami, but a seiche (pronounced "saysh"). Created by high winds or squall lines that exert intense downward pressure, seiches can make Lake Michigan slosh back and forth like water in a bathtub, sending powerful waves racing to the shorelines.

Most Great Lakes seiches are small and go unnoticed, but the phenomenon can trigger huge storm surges and tidal waves that quickly alter Great Lakes water levels.

"A seiche is a smaller version of a tsunami, with a different cause. A seiche is caused by wind; tsunamis are caused by earthquakes," said David Schwab, a research oceanographer at the National Oceanic and Atmospheric Administration's Great Lakes office in Ann Arbor.

Tsunamis are born along the borders of the Earth's tectonic plates, where earthquakes and volcanoes are common. Because the Great Lakes are not situated near the edge of a tectonic plate, tsunamis cannot happen here, said Peter Wampler, assistant geology professor at Grand Valley State University.

Schwab said most Great Lakes seiches only produce subtle changes in lake levels. But given the right weather conditions, a seiche can unleash huge storm surges that endanger human life and coastal structures.

Seiche is a French word that means "to sway back and forth." To understand how a seiche works, blow on a bowl of soup. The tiny waves hit one side of the bowl and reverberate to the other side. A seiche works the same way, but on lakes that span thousands of square miles.

Though less powerful than tsunamis, seiches can strike quickly and with deadly consequences.

That's precisely what happened in 1929, when 45,000 people gathered at Grand Haven State Park on Independence Day. An early morning storm spawned a seiche that kicked up large waves; one swept a 16-year-old Grand Rapids girl off the breakwater and into Lake Michigan, where she drowned.

A second seiche swept across the lake about five hours later, unleashing a wall of water that lashed the Grand Haven beach with 20-foot waves and a powerful undertow that pulled nine more people to their deaths.

"It was a quick and nasty sea," according to a U.S. Coast Guard captain at the scene who was quoted in The Chronicle the next day. "For a short squall, it was one of the worst I've ever seen. Due to the general high water, there were times when the blue sea rolled over the pier, completely submerging the concrete abutments at times." Edward Peters, who operated a bath house at the beach, called the waves "the biggest summer sea I've ever seen."

Bob Beaton, a longtime Grand Haven resident and surfer, said the scariest thing about seiches is that they can strike when the lake is calm.

"Some of the deadliest seiche incidents have happened on calm days," said Beaton, who has spent years researching seiches and is a member of the Great Lakes Beach and Pier Safety Task Force.

Seiches also create fierce rip currents below the surface when the lake level rises and then recedes rapidly. "The waves don't scare me, it's the current that drowns people," Beaton said.

Schwab said seiches are most common in Lake Erie, which is shallower than the other Great Lakes and is often buffeted by southwest winds that cause water levels to fluctuate wildly at opposite ends of the lake, in Buffalo and Toledo.

There have been several cases of seiches in Lake Michigan triggering storm surges and tidal waves that drowned swimmers, swept people off piers, damaged shoreline structures and left boats stranded in mud when the sloshing waters receded.

On July 13, 1938, a seiche caused a massive storm surge that stretched from Holland to Pentwater, according to an article in Hope College's Joint Archives Quarterly. Waves triggered by the seiche drowned three people at Holland State Park. It also triggered "freak high waves" that drowned 34-year-old Oscar Thorsen, who was swimming in the lake in Muskegon, and another man canoeing in Lake Michigan near Pentwater.

A seiche that struck Chicago without warning on a June morning in 1954 increased the lake's water level by 4 feet in just 30 minutes. The rising water was followed by a massive wave, 25 miles wide and as high as 20 feet in some areas, that swept dozens of people off piers. Eight people drowned. Schwab said the killer wave bounced off the Michigan coast before pounding Chicago, pushing water in some areas 100 feet inland of some beaches.

Two years later, a seiche triggered a 10-foot swell in Ludington that sent anglers and beachgoers scrambling for safety. The first swell knocked several anglers off the pier and pushed water 150 feet past the normal water line. The water then receded beyond the water line before a second, larger wave crashed ashore. Carol Dewyer, who operated a bait shop near the north breakwater, was quoted at the time as saying the seiche caused pandemonium on the pier and beach.

"All of a sudden a man said the water was coming in the door of the shop and everyone scrambled for high ground," Dewyer was quoted as saying. "I saw one little boy slip off the breakwater and couldn't get his footing. Then some man ran out in the waves and brought him in," Dewyer added. "All those people (on the breakwater) just threw down their poles and bait buckets and scrambled for the bank."

The storm surge was followed by a squall line that buffeted Ludington with 80 mph winds and heavy rainfall.

Seiches can slosh back and forth across the Great Lakes for hours, depending on the weather conditions. For that reason, the National Weather Service recommends people use caution when swimming in the Great Lakes or venturing out on piers before or after a squall line passes through.

The weather service issues seiche warnings when conditions are right for a storm surge on the lakes.

Beaton, who has surfed the Great Lakes since 1962, said he sees several seiches each year. His most recent encounter with a seiche came while surfing north of the Muskegon breakwater last October. "I see evidence of seiches in Lake Michigan pretty often," he said. "They're not big very often, but I've seen the lake go up or down by a foot in a matter of 30 minutes."

Beaton said listening to weather forecasts is the only way to know if conditions are right for a seiche. He said it's impossible for a lay person to anticipate a seiche by observing the lake or approaching storms. "It's like trying to predict an earthquake," he said.

Reported by Jeff Alexander, Muskegon Chronicle




jeremy L
02-05-2005, 01:57 PM
Yes, i have heard and read much about them. They are very interesting and also dangerous at the same time. Here is another one which occured in 1998:
Description: from the NCDC storm data.
The tug boat Stephen M. Asher sunk in White Lake Channel, just north of Wabaningo between Lake Michigan and White Lake, at approximately 5:15 am EDT due to a seiche created by the derecho moving across Lake Michigan. The crew reported a storm surge swept through the channel into White Lake as the derecho moved onshore. As the storm passed, the water rushed back out of White Lake through the channel, reaching the top of the channel walls. The tug boat, floating against a barge, rolled on its side and sank. No crew members were injured. The company which owns the tug boat estimated repairs would cost $20,000. Damage surveys conducted by the National Weather Service Office in Grand Rapids, MI, in addition to trained spotter reports, local media meteorologist input, emergency management officials, and a review of National Weather Service Doppler Radar, indicate the widespread and severe damage which occurred with the fast-moving line of thunderstorms during the early morning hours of Sunday, May 31st, was caused primarily by strong straight-line winds and isolated wet microburst winds. This particular derecho formed in South Dakota on the evening of Saturday, May 30th, and raced eastward at 70 mph across Minnesota, Iowa, and Wisconsin, before striking Michigan's Lower Peninsula around 4:30 am EDT Sunday morning, May 31st. The derecho event produced widespread 60 to 90 mph wind gusts, which caused extensive tree and structural damage and left over 861,000 homes and businesses without electricity across Michigan's Lower Peninsula. Consumers Energy reported the derecho event was the most destructive weather event in its history, leaving over 600,000 of its customers without power (Consumers Energy is the largest utility company in western and mid Lower Michigan). There were 4 storm-related fatalities reported in the state and 146 injuries (mostly minor). Statewide, approximately 250 homes were destroyed, 12,250 homes damaged, 34 businesses destroyed, and 829 businesses damaged. Damage estimates across the above listed counties totaled over $166 Million. NWS Storm Damage Field Studies suggested highest wind gusts in wet microbursts reached 120 to 130 mph in Spring Lake (Ottawa County) and Walker (Kent County), 100 mph in portions of Montcalm County (including Cody Lake and Stanton), 90 mph in Rockford (Kent County) and Zeeland (Ottawa County), and 80 mph in Big Rapids (Mecosta County), Ludington (Mason County), Sparta (Kent County), and northern Osceola County. On June 24th, President Clinton declared 13 Michigan counties federal disaster areas, including the following 10 from the NWSO Grand Rapids County Warning Area: Clinton, Gratiot, Ionia, Kent, Mason, Montcalm, Muskegon, Newaygo, Oceana, and Ottawa. It took up to 10 days to fully restore power to certain areas including the City of Walker and portions of Montcalm and Gratiot Counties.

Tech Rally
02-05-2005, 03:22 PM
Jermey,

I was out camping with my son the weekend of that storm. It was a boyscout event and I remember laying in our tent, not wanting to get up just yet. All of a sudden the camp siren started wailing. It was a tornado warning. We got all the kids out of the tents and up to the lodge where we gathered in the basement. As it end up, we just got heavy winds and rain. One of the tornado from that storm front past by a few miles north of us. After the storm had past we went back to our camp site. A two foot diameter maple tree had blown down right on top of our tent :yikes: Lost a 60 year old apple tree in my yard from that storm too.

Hi Ho Silver_Joe
02-05-2005, 03:38 PM
Here's a good article.

http://www.miningjournal.net/news/story/0114202005_new04-n0114.asp

jeremy L
02-05-2005, 08:54 PM
TR, what county where you located in during that event? what made it alot of dangerous was the time of year, campgrounds were full because of the holiday weekend. Lucky more were not killed then there was.

Tech Rally
02-05-2005, 09:37 PM
We were just south of you in Lapeer.

jeremy L
02-05-2005, 10:07 PM
oh, ok. Here is more on the effects of the 98 storm on SE michigan:
http://www.crh.noaa.gov/dtx/may31.htm

hitechman
02-05-2005, 11:28 PM
In the mid 50's I was on the beach in Ludington when a big wave came in (wasn't so much of a wave as a rise in the water level--as I recall it happened pretty slowly--took 1-2 minutes to rise). I remember it washed up to the beach road at the Ludington City Park. I was 7 or 8 at the time and though it was pretty cool, but we did have to run from the beach. After the water came in it went back out and for a while there was 200 yards more of beach. I remember seeing the lake bottom without water almost to the end of the bend in the north breakwall.

Steve

idylmoments
02-07-2005, 11:19 AM
I was out of Lexington that day diving the tug Sport. It was a nice calm day and we didn't have the marine radio on. Fortunately, we were done diving and pulled back into port just minutes before the storm hit. Everyone at the dock was saying "you just made it". We wondering what they were talking about when all of a sudden the wind whipped up, ripping off shingles and knocking down branches. We were lucky. My boss at the time lived on the lake and said when the water went out, there was 200 yards of beach and a bunch of smallmouth were left flopping around. Black River was reduced to a stream and all the boats were laying on the bottom.

GVSUKUSH
02-07-2005, 11:28 AM
oh, ok. Here is more on the effects of the 98 storm on SE michigan:
http://www.crh.noaa.gov/dtx/may31.htm


I graduated high school that year and it messed up alot of graduation open houses (and some graduations I'm sure) by blowing over tents in back yards. That has to be one of the scariest storms I've ever been through, I remember getting up at 3 am and standing on the deck with my dad as the winds were starting to whip up, really an awesome sight. I spent the next 3 weeks making boatloads of money hauling limbs and brush away in our neighborhood with my truck and a chainsaw :)

Getaway
02-07-2005, 12:08 PM
Yup, I remember that storm well. I had my boat docked in Liberty Harbor (Bay City) for that weekend and the wife and I were going to stay on it. Well, after hearing about the approaching storm, we headed back to the house to wait it out.

The winds were unbelievable. As it turnes out, we would have been safer on the boat (No trees around to fall on you). I had big tree limbs down in the yard where the boat usually sat, and luckily it was sitting in the marina unharmed.

ESOX
02-07-2005, 12:18 PM
I remember that storm.Radio kicked on on the boat (Love that automatic weather alert) We hightailed it back to the Harley launch from the flats. Driving home I was dodging debris. In the driveway, Truck and boat got barely missed by a maple when it came down. Had a big pine tree snap off and land on the house. Moderate damage as the boughs cushioned the fall. But then the tree rolled off the roof and landed on the A/C unit and privacy fence. Hate when that happens. LOL State Farm treated me very well.

ESOX
02-07-2005, 12:22 PM
BTW, don't have pine trees too close to the house, darn things like to blow over. My house got hit twice in the last decade. Only two trees to go.;)

DuckDog
02-07-2005, 12:46 PM
This happened while we were duck hunting. Here is the story:

http://www.weatheranswer.com/public/NWS_Edmund_Fitzgerald.pdf#search='storm%20november %2011'

TSS Caddis
02-07-2005, 03:20 PM
When I was living in Hawaii on a project for work many moons ago, 2nd day there work was cancelled because of Tsunami warning. We were in a hotel just across from the Ali Wai marina. Boats were leaving the marina all morning to avoid any wave. Luckily it never happened, but I guess they have gotten hammered enough times when they thought there was no danger and it was a real event that any time there is a major earth quack anywhere from Japan to Alaska they have a warning.