Letters

Letters 05-02-2016

Facts About Trails I would like to correct some misinformation provided in Kristi Kates’ article about the Shore-to-Shore Trail in your April 18 issue. The Shore-to-Shore Trail is not the longest continuous trail in the Lower Peninsula. That honor belongs to the North Country Trail (NCT), which stretches for over 400 miles in the Lower Peninsula. In fact, 100 miles of the NCT is within a 30-minute drive of Traverse City, and is maintained by the Grand Traverse Hiking Club...

North Korea Is Bluffing I eagerly read Jack Segal’s columns and attend his lectures whenever possible. However, I think his April 24th column falls into an all too common trap. He casually refers to a nuclear-armed North Korea when there is no proof whatever that North Korea has any such weapons. Sure, they have set off some underground explosions but so what? Tonga could do that. Every nuclear-armed country on Earth has carried out at least one aboveground test, just to prove they could do it if for no other reason. All we have is North Korea’s word for their supposed capabilities, which is no proof at all...

Double Dipping? In Greg Shy’s recent letter, he indicated that his Social Security benefit was being unfairly reduced simply due to the fact that he worked for the government. Somehow I think something is missing here. As I read it this law is only for those who worked for the government and are getting a pension from us generous taxpayers. Now Greg wants his pension and he also wants a full measure of Social Security benefits even though he did not pay into Social Security...

Critical Thinking Needed Our media gives ample coverage to some presidential candidates calling each other a liar and a sleaze bag. While entertaining to some, this certainly should lower one’s respect for either candidate. This race to the bottom comes as no surprise given their lack of respect for the rigors of critical thinking. The world’s esteemed scientists take great steps to preserve the integrity of their findings. Not only are their findings peer reviewed by fellow experts in their specialty, whenever possible the findings are cross-checked by independent studies...

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Strange Oscillations: Mysterious ‘seiche‘ Drops Bay Water Level by 18 Inches in Two Hours

Sandy Bradshaw - June 27th, 2002
On Tuesday morning, June 4th, 2002, West Grand Traverse Bay‘s water level dropped an astonishing 18 inches in less than two hours. A sailor was getting his boat ready for summer mooring and by the time he was all set to go - too late! His boat was stuck in a sandbar due to the sudden water level drop.
Known as a seiche, it is a phenomenon which occurs frequently on the bays of Northern Michigan. What is a seiche? Pronounced “saysh,“ you may compare it to water sloshing in a bathtub. Seiches are tide-like rises and drops in coastal water levels, (occurring both in fresh water and ocean waters) caused by prolonged strong winds that push water toward one side of the water body. This causes the water level to rise on the downwind side of the lake and to drop on the upwind side. As the wind diminishes, the water sloshes back and forth, with the near-shore water level rising and falling in decreasingly small amounts on both sides of the lake until it reaches equilibrium.
Seiches occur most in waters that are more or less surrounded by land, such as lakes, fjords and gulfs. Otherwise there would not be that sloshing back and forth that characterizes a seiche. Water blown onto a shore will just ebb back into the ocean if there is no opposite shore to reflect the wave. Seiches can also be caused by earthquakes, even very distant ones. Seiches triggered by earthquakes thousands of miles away have been reported.
“Seiches occur all the time on the bay,“ said John McKinney, past Maritime Heritage Alliance board member and Michigan Sea Grant agent. “This one was a bit larger than usual for Grand Traverse Bay though. Atmospheric pressure and wind changes helped contribute to the quick rise and fall of the bay. The western end of Lake Erie experiences large ones quite often - sometimes as high as six feet,“ he noted.
“Historically no one has taken records of the seiche effect,“ McKinney continued. “They are usually so small no one even notices them. A few years back we had a Japanese researcher, Dr. Uehara, take records on the bay with a special monitoring instrument every ten minutes. He conducted those measurements for six month stretches over a period of several years. This was documented on a graph, and shows seiche occurs constantly.“
According to Hans Joerg Rothenberger, a Swiss science and history buff
and skipper of a gaff cutter in Greece where seiches are
frequent, the word was first used in a scientific context by his
compatriot François-Alphonse Forel (1841 - 1912). “He was a professor of
anatomy and physiology, but known in international science rather as the
‘father of ‘imnology,‘ i.e. the science of lakes,“ said Rothenberger.
“Forel used the French word ‘seiche‘ for the first time in 1869 after
watching the phenomenon on Lake Geneva, a lake roughly the size of the
Grand Traverse Bay. He reported a seiche of eight days with about 200
oscillations. By the way, the question of the original meaning of the
word ‘seiche‘ gave rise to various theories, none of which is very
convincing.“
 
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