Forming of Baikal ice
Each year Lake Baikal is
covered by a thick layer of ice. At the beginning of winter (December), storms
form types of stalactites and stalagmites on the rivers, some reaching as much
as 10 meters. As the temperatures decrease further and the snow comes, these
ice formations, "choulga" begin to join together on the lake to
create large plates. In certain areas, water is frozen so quickly by the cold
that the ice it forms is absolutely smooth and transparent. Once temperatures
drop below -20'C, for 3 or 4 days, the sea ice thickens very quickly, from 5 to
7 cm per day. During the first half of the month of January, the sea ice covers
the lake. From the North to the South the thickness varies between 70 and
130cms. The ice blocks can obtain a height of 3 meters and in some instances as
much as 5 meters.
Composed of fresh water,
the ice of Lake Baikal is solid: one square meter of ice with a thickness of
50cm can support 15 tonnes. In winter, we can move around on the lake in almost
any vehicle. The only danger comes from the crevasses which form in the
sea-ice, and which can be as much as 2 metres wide. These crevasses can be
several hundred kilometres long and in many instances these will not freeze at
all and will change dimensions during the season. These crevasse rivers form
part of the thermal articulation for the sea-ice which is constantly moving.
With temperature changes some small crevasses can form, called
"trechiny", and are quite frequent during both spring and autumn. For
those who are not used to the noise it can be somewhat startling, as the loud
bang is often several times louder than a gun shot.
In March the melt begins
even though some areas may actually continue to thicken. As this process
continues ice mounds may form as large as 10 meters high. This is caused by
certain ice plates moving under others giving the effect we could imagine after
an earthquake. The full melting process is underway by April in the south and
will take until July to reach the north.
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