ABSTRACT: Natural hazards in Canada.

CGRG Bibliography of Canadian Geomorphology
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Hazardous geophysical processes operate in all parts of Canada and adjacent territorial waters, and are responsible for frequent natural disasters. The west coast of Canada has the highest incidence of earthquakes in Canada and the country’s only active volcanoes. Earthquakes and volcanic eruptions are driven by lithospheric plate interactions beneath the eastern North Pacific Ocean. Magnitude 9 earthquakes are possible along the subduction zone off Canada’s west coast. Moderate to large earthquakes also occur in southern Ontario and Québec and in parts of Northern Canada. Tsunamis triggered by great earthquakes in the Pacific Ocean threaten communities on the west coast of Vancouver Island. The tsunami of the giant 1964 Alaska earthquake caused over $10 million to Port Alberni, Tofino, Hot Springs Cove, and other west coast communities. Canada’s only tsunami fatalities, however, were on the Atlantic coast. A large offshore earthquake in 1929 caused a tsunami that drowned 27 people in Newfoundland. Canada’s volcanoes are part of the Pacific Ring of Fire and range from small cinder cones to large stratovolcanoes that have erupted repeatedly during the Quaternary. Canada’s greatest volcanic hazard derives from explosive eruptions in Washington and Alaska, where volcanoes are more active than our own. Flooding causes more damage than any other physical process in Canada. All streams and rivers flood, but some are much more hazardous than others. Flooding is caused by a variety of processes, including rapid melting of snowpacks during spring and summer, ice-jam formation and break-up, convective storms, and outbursts from moraine- and glacier-dammed lakes. In addition, the southern parts of Central Canada and the Maritimes are vulnerable to flooding from hurricanes that form in the tropical Atlantic Ocean. Historical records indicate that landslides and snow avalanches have killed more than 600 people in Canada since 1850. Landslides are common in the Cordillera, along the walls of river valleys cut into Cretaceous shale on the Interior Plains, and in sensitive glaciomarine clay in the St. Lawrence Lowlands. Waves generated by landslides that enter rivers and lakes have caused substantial damage in several parts of the country, and structures at the edges of deltas may be damaged or destroyed by underwater landslides. Avalanches occur widely in the mountains of western Canada, regularly blocking transportation routes and killing skiers and snowmobilers. Projected climate warming will reduce the extent of permafrost in northern Canada, accelerating coastal erosion along the Beaufort Sea coast, damaging infrastructure, and increasing some types of landslides

Bibliography of Canadian Geomorphology