Glaciers Today
A glacier is a body of snow compacted into ice, large
enough to move under its own weight. Valley glaciers start as snow
fields in the mountains where snow accumulates layer by layer. The snow
first becomes granular and finally changes to solid ice. Ice is a rather
weak solid and will spread like batter on a griddle if there is
sufficient pressure on it. When the ice is thick enough, its weight
causes the bottom ice to spread outto flow down the steepest
slope. The ice is then a glacier.
The glaciers that remain in the Olympic Mountains
today are small indeed compared to the extensive glaciers that formerly
filled the valleys and sculptured the mountains. Many have disappeared
completely, leaving only the shape of the land to testify that they once
were here. However, more than 100 glaciers, having a collective area of
at least 25 square miles, remain in the Olympic Mountains. Mount Olympus
alone has 6 major glaciers, and the total area of permanent snow and ice
on it is more than 10 square miles. Several other mountains also have
glaciers, notably Mounts Anderson, Christie, Tom, and Carrie.
In addition, there are numerous snow patches that
remain from one winter to the next but are not thick enough to form
glaciers. Viewed from a high position, a panorama of north-facing slopes
presents a profusion of snow and ice patches. The presence of so much
snow and ice in mountains of modest height does not mean they are
enveloped with inhospitable cold. It is due to the abundance of winter
snow and considerable cloudy weather which retards its melting. Glaciers
develop where snowfall exceeds the amount melted.
Like nearly all glaciers everywhere, those in the
Olympic Mountains are dwindling. Each year they become shorter and
thinner. Between 1938 and 1951, Blue Glacier, on the north side of Mount
Olympus, melted back 776 feet. A comparison of old and recent
photographs of Blue Glacier indicates that it may have shortened by as
much as three-fourths of a mile since 1919. If excessive melting
continues the glaciers will eventually disappear.
PRECIPITATION ON MOUNT OLYMPUS MAY BE AS MUCH AS 250
INCHES SOME YEARS. Photo by Richard Owens, Jr.
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