The morning after Ketchikan we were supposed to be traveling through Tracy Arm, a fjord in Alaska. I had heard that it was spectacular, so I got up early--and then went and woke up the rest of my party. Wow! These pictures just don't do it justice.
Another passenger who has seen Norwegian fjords says that Tracy Arm is actually more impressive--steeper cliffs, and deeper water. Fjords are the result of glaciers scraping through a valley during the last Ice Age, when ocean levels were typically 300-350 feet lower than today (all the water was locked up in glaciers), and so when the ocean levels rose, those glacier-filled valleys became steep inlets of the ocean.
In many cases, we had frozen streams all the way down to the water.
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In other cases, the streams were still flowing. (Contrast problems, combined with subdued lighting from cloud cover, impair the quality of some pictures--sorry.)
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There were miniature icebergs everywhere, some white, some blue, depending on the number of air bubbles contained in the ice. I didn't see any calving off of glaciers, but perhaps I should have been up earlier.
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And some of these were genuine glaciers, down to sea level!
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There were hanging valleys, too, which are what happens when glaciers gouge out a tributary valley more slowly than the main glacier gouges out the main valley.
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The naturalist onboard gave a very well done presentation over the loudspeakers about the geology of Tracy Arm--and I was both pleased and surprised to hear him explain that the relationship of human activity to the shrinkage of these glaciers remains a controversial point among glaciologists. Regular readers of my blog won't find this surprising--I'm sure it surprised many of the passengers.
Where Tracy Arm meets the Pacific Ocean is a terminal moraine. Terminal moraines are where a glacier deposits rock and gravel at its end. The naturalist explained that the glacier extended up to this terminal moraine as recently as 400 years ago--meaning that whatever is causing the glacier to recede is a bit older than the Industrial Revolution.
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