- human history coincides with a
geological epoch with an abundance of snow and ice but comprising
about only 1% of earth history
- the Pleistocene Ice Age, the last two
million years of earth history, ended only 10,000 years ago (arbitrary
limit), compared to the duration of a typical interglacial measured in
10s thousands of years; thus the earth is likely just between major
glaciations
- the most recent advance of mountain
glaciers, the Little Ice Age, began about 900 years ago and peaked
around 1850
- fresh Little Ice age moraines are
clearly evident in the Rocky Mountains, 100s of metres beyond the
present glacier margins
- for example, the early travelers
between Banff and Jasper used Wilcox pass because the terminus of
the Athabasca glacier was in bottom of the valley now traversed by
the Icefields Parkway
|