Ice

There is a reason that Canada is nicknamed "The Great White North". In most parts of the country, we can count on the presence of snow and ice from late autumn through mid-spring. Normally, Canadians are prepared for anything winter can dish out, meeting snow and ice head-on. Bundled up in parkas and toques, Canadians enjoy the season by skiing, tobogganing, snowmobiling, playing hockey, building snowmen and smiling through billows of visible breath. But ice can be just as dangerous as it can be fun, and when it catches people off guard, the results can be disastrous.

To most Canadians, winter storms are probably the most familiar manifestations of the malevolent side of ice. They can come in the form of blizzards, snow squalls, snowbursts (sudden, severe snowfalls) and, in the Prairies, near-zero visibility blowing and drifting snowstorms called Alberta Clippers.

Most destructive, though, are ice storms. Freezing rain and thick sheets of ice can damage homes, snap limbs off trees and pull down power lines and hydro towers. During the Montréal ice storm of 1961, many residents were without hydro for days. Schools were closed, and thousands of people trekked from the suburbs to the downtown in search of heat, light and running water. On Christmas Day 1986, Ottawa was struck by an ice storm that left one in four homes without power and downed thousands of trees.

In winter storms, the snow comes one flake at a time. But in an avalanche, tonnes of snow come all at once in huge slabs or massive waves. An avalanche can move at up to 130 kilometres per hour, crushing and burying anything -- or anyone -- in its path. Over the years, hundreds of Canadians have died in avalanches, most of them railway workers, skiers or hikers in the Rocky Mountains.