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Alaska has an estimated 100,000 glaciers, ranging from tiny
cirque glaciers to huge valley glaciers. There are more active
glaciers and ice fields in Alaska than in the rest of the
inhabited world. The largest glacier is the Malaspina at 850
square miles. Five percent of the state, or 29,000 square miles,
is covered by glaciers.
A glacier is a strange and unfamiliar thing. It looks like land, but it flows
like water. Glaciers can be larger than a city or even a state, and yet they
move constantly, sometimes suddenly, and they can bulldoze straight
through mountains. Nothing else looks like a glacier. They’re white, gray,
and fluorescent blue. They drape gracefully through the mountains, but
they also crack in enormous shards.
Glaciers are rivers of ice that flow from ice packs high in the mountains, where
more snow falls than melts. In constant motion, they can move ahead at speeds of
several feet a day, or sudden surges of as much as 300 feet. Some glaciers,
called receding glaciers, are
shrinking due to increased melting or a lack of new snow to feed
them.
Tidewater glaciers flow to the sea and are found at the head of fjords or inlets
which they carved while retreating. Calving occurs when pieces of a tidewater
glacier break off and fall into the sea. The creaking sounds associated with
calving glaciers and the roar as pieces fall into the sea are as impressive as
the visual scene. The beautiful blue color associated with glaciers is created
by the density of the ice which absorbs all the colors of the spectrum except
blue, which is reflected. Tidewater glaciers are laciers that reach the
sea, while freshwater glaciers end in a lake, and valley
glaciers end in a valley. Hanging glaciers have only descended
part way down a mountainside. Terminal moraine is the ridge of soil that marks the furthest advance of a
glacier before it began to recede. Portage Lake was formed behind the terminal
moraine of Portage Glacier. Sometimes a dark stripe can be seen running down the middle of a glacier. That
is pulverized rock that was pushed up between two merging glaciers.
Glaciers can be dangerous. Snow can mask deep crevasses in glaciers. McKinley mountain climbers rope
themselves together not just to reduce the danger of falls from steep slopes but
also to reduce the risk of falling into one of these hidden pits in the glaciers
on the lower slopes of the mountain. Ice crumbling off the face of a glacier also can be dangerous. A visitor to Exit
Glacier several years ago was killed when ice fell on her. Paths at that glacier
are now roped off to prevent visitors from so closely approaching the glacier.
With all the glaciers found in Alaska, there are few that should
be on your must see list as a tourist:
Prince William Sound Glaciers (Whittier): Less than two hours
from Anchorage, the port town of Whittier provides access to
northwestern Prince William Sound, one of Alaska’s most beautiful
and heavily glaciated waterways.
Kenai Fjords National Park (Seward): Here you find Exit Glacier
(one of the few glaciers you can walk right up to) and the magnificent
glaciers still carving the fjords, reached only by boats from
Seward. This forbidding and untouched area, where mountains
shoot a mile high straight out of the sea, is also among the best for
seeing marine mammals and birds.
Ruth Glacier (Denali National Park): Forget the traditional image
of glacier ice falling into the ocean — this is a chance to land on
one of Mount McKinley’s glaciers in a ski plane, get out, and look
around. These flights, mostly going from Talkeetna, are among the
most spectacular experiences a visitor to Alaska can have.
Juneau Ice Field (Juneau): Helicopters from Juneau fly over the
immense ice field that lies beyond the mountains bordering the
town. Visitors can just look, or join guided hikes on the ice, or even
get in a dog sled and go mushing on the glaciers.
Glacier Bay National Park (Juneau): Glacier Bay
is a collection of fjords and inlets, home to 16 active
tidewater glaciers, all five species of Pacific Salmon and 25
percent of the total number of bird species in all North
America. It is located in the middle of Glacier Bay National
Park and Preserve, a 3.2 million acre sanctuary. In just over
200 years, the ice of Glacier Bay has retreated 65 miles. When
Captain George Vancouver visited in 1794, the entrance to the
Bay was a wall of ice. |