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grew up in Logy Bay, a small community just
north of St. John's and I have always thought of icebergs as just
another element in nature, something everyone is familiar with,
like a tree or river. Now I realize there are not many places in
the world where you can easily view icebergs and that I am fortunate
to have them in my back yard. People travel here from all corners
of the globe to study, photograph and otherwise admire these floating
glacial islands. With all this interest, I decided to delve into
the world of icebergs and learn their story. It begins in the high
artic.
The
majority of icebergs form along the western coast of Greenland with
a small percentage originating from Canadian islands. Greenland
is the largest island in the world1 and is almost entirely
covered by a huge ice cap made up of many glaciers. As snowfalls
accumulate over the years, the glaciers flow outward from the centre
of the cap under the pressure of their own weight. Near the coast,
this glacial creep can reach speeds in excess of 20 meters
a day. When the ice reaches the shoreline, pieces of the glacier
break off and fall into the ocean, a process known as calving. Between
10,000 & 15,000 bergs are formed like this every year.
Often
adrift in Baffin Bay for a year or more, the icebergs eventually
wind up in the Labrador Current and slowly make their way south.
At the mercy of the ocean tides and strong winds, they meander their
way along the coast of Labrador and the island of Newfoundland,
slowly melting as they go. The number of icebergs that migrate south
varies from year to year, but on average almost 400 bergs make it
as far south as St. John's, or 48 degrees North Latitude. This annual
parade of ice has earned the band of ocean along the southeast coast
of Newfoundland and Labrador the nickname Iceberg Alley.
Bergs
that frequent the waters of Newfoundland and Labrador are commonly
several hundred thousand tons and tower many meters above the sea,
but bergs in excess of 15 million tons have been observed.
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This
may sound big, but icebergs that calve off the ice sheets in Antarctica
can be many times larger. In fact, bergs in excess of a trillion
tons have been recorded off the Ross Ice Shelf.
Regardless
of their size, however, no two icebergs are alike. Some are practically
featureless flat slabs, while others are much more interesting.
Arches, overhangs and sharp peaks are all common features. Sometimes
bergs will cradle shallow pools of water within their frozen landscape.
These pools reflect some of the prettiest blues I have ever seen.
Owing
to ocean wave action, indentations form at the waterline creating
a ring around the iceberg. Because 7/8ths of the berg's mass is
under water, it slowly rises out of the water as it melts. This
creates a succession of rings, each one a different width and depth.
Like the hands of a potter shaping clay, Mother Nature carves each
berg into a captivating work of art.
Glacial ice is formed over many decades, as successive layers of
snow are eventually compressed into ice. This process encapsulates
tiny pockets of air, it is these air bubbles that give icebergs
their brilliant white appearance. Occasionally, a band of ice with
no air bubbles, created from glacial melt water, will be uncovered.
When the sun illuminates these bands they glow a cool blue, and
the contrast with the pure white ice makes for quite a spectacle.
Because
icebergs are in the process of melting, they are constantly changing
shape. These alterations slowly shift its centre of gravity and
the berg can abruptly roll over or split apart into smaller bergs
without any hint of warning. If observed from a safe distance these
events can be spectacular, with loud cracking noises and huge splashes,
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but
falling chunks of ice or churning water from a roll can be dangerous.
When viewing icebergs,
it is always best to be accompanied by an experienced guide or aboard
one of the many tour boats available.
As glamorous and fascinating as icebergs are they can also be treacherous
for those who work on the ocean. In the past, icebergs have claimed
many lives. Ships colliding with icebergs in heavy fog or in the dark
of night were not uncommon. The most famous such collision was, of
course, with the RMS Titanic. Today, there are international
ice patrol organizations that monitor location, movement, size and
number of icebergs on a constant basis. This affords mariners and
offshore drill rigs the ability to navigate or otherwise take the
necessary precautions to avoid disaster.
Apart
from their beauty and wonder, the ice is very pure as it was formed
from fresh water that froze thousands of years ago. There was no
pollution and acid rain was simply non-existent. For this reason
icebergs are now being harvested and products such as Iceberg Water
and Iceberg Vodka are being sold around the world.
In
short, that is an iceberg story. But, just like the Grand Canyon
or a towering old growth on Vancouver Island, these castles of ice
are something you have to see for yourself. According to legend,
the Irish monk, Saint Brendan made a sixth century voyage across
the Atlantic, and the ancient Latin text describes his ship as having
"passed by towering crystals that rose up to the sky." Imagine the
awe of such an encounter. Stately. Bold. Magnificent. That awe is
still real for me today, and I have seen them many times.
1.
Australia has a larger area but is classified as a continent.
©Magical
Places 2002
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