|
Description: |
The alpine occurs at
high elevations throughout British Columbia and
has the harshest climate of any of the biogeoclimatic
zones in British Columbia. Temperatures are cold
for most of the year, with much wind and snow. Temperatures
remain low even during the growing season, which
has an exceptionally short frost-free period. Mean
annual temperatures range from 0° to 4°C, and the
average monthly temperature stays below 0°C from
7 to 11 months of the year. The mean temperature
of the warmest month is less than 10°C. A great
deal of precipitation falls in this zone, mostly
as snow. The Coastal Mountain-heather Alpine Zone
(CMA) occurs along the windward spine of the Coast
Mountains and the mountains of Vancouver Island
and the Queen Charlotte islands where the snowpack
is deep and summers are moderated by maritime influences.
The treeline in this environment is lowered by
heavy and prolonged snow cover and can be as much
as 900 m lower than in the alpine of comparable
latitudes in the dry interior. Alpine begins at
1600 m in the south, descending to 1000 m in the
north. Though this zone is extensive, the most of
the land area is occupied by glaciers or recently
exposed bare rock at the elevation of true alpine.
|
