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Thursday, June 21, 2007

Tips of icebergs and humps of whales


I always thought the rule-of-thumb on icebergs was that only one-seventh appeared above sea level. However, according to Nick Jans, author of “Alaska’s Tracy Arm and Sawyer Glaciers,” only 10 percent of the ice can be seen. At the visitor center for Juneau’s Mendenhall Glacier I met the photographer of this beautifully illustrated hardcover book -- Mark Kelley. He said that if a person had only one day in all of Alaska, the iceberg-laden Tracy Arm fjord would be the place to go. I cannot disagree, especially when one is lucky enough to go there on one of the few sunny days that the Juneau area enjoys on any given summer – our cab-driver counted only 13 clear days last year during the warm season.

A wild unfinished Yosemite… no ice work … surpasses this.
-- John Muir, who explored the Pacific Northwest in the late 19th century

Our boat captain, who’s made over 1500 trips to Tracy Arm, brought us to within a stone’s-throw (a good, flat skipper-rock maybe) of the North Sawyer Glacier. According to author Jans, when a big piece of ice calves off, it can be especially dangerous as a ‘shooter’ coming back out of the depths after its plunge. The deep blue bergs come from compressed depths (900 below sea level) of the glacier where air has been completely squeezed out.

PS. If you want to get a bit off the beaten channel for cruise ships on the Alaska’s Inside Passage, visit Sitka on Baranoff Island. I recommend you spend some time on land and stay at a place like Old Sitka Rocks maintained by my buddy Bob Medinger and his wife Barb. Bob captained us to a fantastic volcanic island sanctuary for puffins and other sea birds. On the way there and back, only few miles from Sitka’s harbor, we saw numerous humpback whales – close enough to really sense their awesome size and speed – one of the leviathans knifed past our boat only a few hundred yards off to starboard at over 5 knots! (I was watching from the above on the main mizzenmast … just kidding.) By the way, Alaskan whalers caught a bowhead last month that had a century-old harpoon fragment embedded in its neck, thus pinning the marine mammal’s age at 115 to 130 years!

1 Comments:

  • At 5:25 AM, Anonymous Eric Kvaalen said…

    I think the amount of an iceberg above water varies. It could depend on the amount of air bubbles and whether there are pockets of brine concentrated by the freezing process.

     

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