The Cold-Chain Chronicles: Lake Superior, The World's Largest "Gel Pack"
I have lived nearly all my life within ten miles of Lake Michigan's shoreline. I don't sail. I am not a fisherman. In fact, water sports of any kind don't appeal to me. But there is something about the lake that does - and the feeling of comfort and familiarity that it gives me, extends beyond its shores to its sister Great Lakes. My affinity for them, like the lakes themselves, is inter-connected.
I have spent many vacations exploring the small towns, islands, bays and beaches of the more than 10,000 miles of shoreline that contain the Great Lakes. I have discovered that each of the five lakes has its own personality, character and mood. They are as different and unique from each other as can be.
One thing I have learned through my travels around America is that - beyond those who live in the upper Midwest, the Great Lakes are a bit of a geographic mystery - an incongruous break in the landscape of flatland prairie and evergreen forests somewhere around Chicago or Detroit or Cleveland.
To truly appreciate these jewels, you have to spend time with them - get to know them and the people who call the lakes their own. The most common experience of those who visit these lakes for the first time is the realization of their nearly incomprehensible enormity, their importance to local culture, economy, and weather. The phrase "cooler by the lake" is a common mantra of all television meteorologists who boast their forecasts from the cities throughout the region.
The power and volume of these fresh water giants are humbling. Consider this: a full 20% of the Earth's fresh water is contained within four of the Great Lakes. 750,000 thousand gallons a second spills over the falls at Niagara and into Lake Ontario in relentless pursuit of draining the excess water from the other four lakes. These five sisters are beautiful and bountiful, languid and lurid - effortlessly producing 40 pound salmon, 40 foot waves, 40 inch snowfalls or 40 knot winds from a dead calm - known as white squalls. And they are treacherous, having claimed more than 6,000 commercial vessels in their short maritime history.
But for as beautiful and as overwhelming as they are, there is one among them that is deeper, darker, more mysterious, and far more brooding than the rest - Lake Superior. Its chalcedony beaches, thick, tree-lined coasts, and soaring mineral cliffs form the edges of the largest concentration of fresh water in the world. So large and so deep is Superior that it could contain the volume of all the other Great Lakes combined - with enough room left over for another three lakes the size of Lake Erie. It's 3,000 cubic miles of water is retained for 191 years before it is fully turned over to the Saint Mary's River to co-mingle with Lake Huron. These facts, if you'll pardon the pun, are unfathomable to most.
"Superior sings in the rooms of her ice water mansion."(1) Gordon Lightfoot's lyric regarding the greatest of the Great Lakes vividly describes not only its vastness and clarity, but also its character. It's 31,700 square miles of surface water - approximately the size of the state of South Carolina, can, with equal disregard, cradle kayakers on mirrored perfect stillness or, in its fury, swallow a 729 foot steamship (The Edmond Fitzgerald).
Superior does not benefit from trade winds, currents and tides like the open and less dense salt oceans of the world. Her confinement and depth, which runs to a maximum of 1,332 feet, makes her waters dark and dense, and with essentially no agricultural run-off -clear as Waterford crystal. Visibility in many places can be to 100 feet. But above all, Superior is cold. Extremely cold. The average water temperature is 5 degrees C. Its effects on its surroundings works in the exact same way a gel pack would within an insulated package... only on a scale millions of times larger.
A related posting to this blog, "Gel Packs - How Frozen Is Frozen?" (Technical Discussion archives) addresses, among other things, water's amazing specific heat capacity. With that knowledge in mind, it seems almost unimaginable that there is not enough energy emitted from months of blazing summer suns to warm Superior's waters to a temperature that won't stop your heart. Nor do the long, bone-chilling winters ever cause the waters to freeze. From summer to winter the water temperature of the lake never deviates by more than a few degrees.
One of the more remote and mystical places I have traveled along the Great Lakes, is to the Kewenaw - a crooked finger of land that juts into Lake Superior's south shore in Michigan's Upper Peninsula (U.P.). It's one of those places you can't get to by accident. You have to want to get there. Few do. Fewer still have the resolve to stay.
Among the many peculiarities you will notice in the once-proud copper mining towns rusting among the pine forests of the Kewenaw, are that the parking meters are not located at the curb but attached to nearby buildings; fire hydrants and mail boxes stand 6 feet out of the ground; and many of the houses have, where second story windows should be, entry doors with no porches, railings or stairways. Then, you realize that these are not remedial construction blunders by local Finnish craftsmen, but clever adaptations to the Kewenaw winters.
Winters are particularly long and challenging as residents there are frequent recipients of massive amounts of a rare phenomenon known as "lake effect" snow. It is caused when the frigid Arctic air, locally known as an Alberta clipper, comes whistling down the Manitoba plains. When the dry air reaches the warm, open waters of Lake Superior, it condenses. By the time it reaches the first significant landmass; the colder air hovering over the Kewenaw Peninsula, it precipitates in the form of snow. Lots and lots of snow. It can snow steadily for days on end. A friend of mine from the Kewenaw town of Calumet once told me that in February, 1979, it snowed only twice - once for 17 days, and the other for 11 - and that he was tired of having to call his dog off the roof. They received over 390 inches of snow that winter. It's difficult to imagine nearly 400 inches of snow on the ground. The picture below from a Detroit Free Press article puts it into perspective.
All this reminiscing about my Great Lakes travels has rekindled my affection for them. My wife, Colleen, and I are are leaving in the morning on a 900 mile circle tour of Lake Michigan, to view the on-set of fall colors in the U.P., and spend a few relaxing days up where Lakes' Michigan and Huron wed their waters - the Grand Hotel on Mackinac Island. Until next time...
(1) Gordon Lightfoot. "The Wreck of The Edmond Fitzgerald". Copyright 1976, Warner Bros. Music
