Monday, October 29, 2007

Extremes

We rest uneasily on Alaska’s shores. It isn’t just the light (or lack of it). Perhaps this sense of precariousness has something to do with its geological newness.

Here, the ice retreated only very recently. Two hundred and fifty years ago, Glacier Bay did not exist: it was under a mile of ice. Seven miles from my house, on the way to town, the Mendenhall glacier—what is left of it after the drastic melting of recent years—comes right down to the floor of the valley. We are perilously near the meeting point of three massive tectonic plates at Mt Fairweather, 80 boat miles distant. Catastrophic earthquakes, volcanic eruptions, tsunamis are normal life along the Pacific Ring of Fire.

And there is the weather. The Gulf of Alaska generates weather for much of the northern western hemisphere. Huge storms howl over the coast with complete indifference, sometimes without warning. Many waters meet outside my window, and these, too, generate weather. Sometimes the wind blows north and south simultaneously, incising a sharp line down the middle of Favorite Channel to the marker at the northern end of Portland Island. The prevailing rain wind is southeast, but snowstorms ride the Yukon Express, streaming down from the north.

The sea can only respond: flat, calm, oily, rumpled, frothing, churned by williwaws, roiled by waterspouts, tossed into chop, or piled up into gigantic rollers that churn relentlessly to the beach. How do you measure a wave? from the crest of one to the trough of the next, using whatever is available: ten large ducks or fourteen small ones, half a whale, a buoy that appears and disappears behind the liquid peaks surging past, a small boat smashing through the spray.

Wind: there is a fair-weather winter wind called Taku that blasts off the ice field that runs 1100 miles along the coastal ridges from just north of Vancouver, nearly a thousand miles to the south, to Skagway, a town about 150 miles to the north. The quirks of topography protect my house, but nearby the wind often exceeds hurricane force, with readings of over 100 mph regularly recorded on Sheep Mountain just south of town, eighteen miles to the south. Point Retreat, ten miles to the northwest, is the lee shore of the 100-mile fetch down Lynn Canal from Haines. Winds there at the lighthouse have been clocked at 226 mph.

But then, everything seems extreme in Alaska. It contains two of the highest visible geographical profiles on earth. The big mountain in the Alaska Range, Denali, rises 20,320 ft. from a 2,000 ft. elevation plain, while Mt St Elias, 200 miles north of here, rises 18,008 ft from the sea. By comparison, Everest rises 29,028 feet from a plateau that approaches 9,000 ft. elevation.

Even Alaska’s relationship to the magnetic pole is extreme. In our neighborhood at latitude 58 (by comparison, Oslo, Norway, is latitude 60) there is approximately 30 degrees magnetic deviation from true north. This deviation is continually increasing, the precursor of an expected global magnetic flip; in some areas you cannot trust a magnetic compass at all. If the charts no longer speak of lurking monsters in uncertain waters, they say “magnetic disturbance”. Hope that you will not be navigating one of these areas in fog or a snowstorm. Pray that a storm-from-nowhere will not erupt and smash your boat to fragments. People vanish here; their vessels capsize, they lose their way in the forest or get eaten.

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