Weather Impacts in Canada

Roger Street
Environmental Adaptation Research Group
Atmospheric Environment Services
Downsview, Ontario, Canada

David Etkins
Environmental Adaptation Research Group
Atmospheric Environment Services
Environment Canada

David Phillips
Policy, Program and International Affairs Directorate
Atmospheric Environment Services
Environment Canada


Canada is subject to a variety of hydrometeorological hazards and disasters. An inventory is being assembled and is summarized in figure 1. This chart shows the number of identified events by hazard for which cost estimates could and could not be made. The total of known costs are identified in 1995 dollars at the end of each bar. Tornadoes are not included, since there have been over 2,300 known Canadian tornadoes during the period 1961-1996. I would also note that a precise criteria was not used to include or exclude particular events but rather events were included if the information source suggested a "significant" impact of some sort (meteorological, social or economic).

Droughts, by far, are the most costly hazard, although they rank fourth in terms of frequency. It is worth noting that for hurricanes, only economic costs associated with Hazel (1954) have been included.

An historical survey of Canadian disasters shows that 44% of them are weather or climate related, that almost 1/3 of all disaster have occurred at sea, and that 80% of those were weather related.

Natural disasters are the extreme of natural hazards and occur when social vulnerability is triggered by an extreme event. The costs Canadians incur from hazards are a function of our adaptive decisions. Unsafe conditions result from a number of social forces which are rooted in limited access to power, economic resources and the nature of political and economic decisions.

These costs of natural hazards can be broken down into social costs and economic costs.

Social Costs

In terms of social costs the following statistics give some indication of the overall magnitude:

Economic Costs

There are two fundamental economic costs associated with natural hazards - adaptive costs and impacts, response and recovery costs. Adaptive costs are those associated with protection, reduction of vulnerability or risk, education and research. These costs are difficult to estimate and little research has been devoted to increasing our understanding of these costs. One preliminary estimation of Canadian adaptation costs suggests that $13.7 billion is spent annually; however, this is likely underestimated by some unknown amount.

Impacts, response and recovery costs are those incurred when protection fails or no adaptive response is taken. Some examples for Canada include:

Canadian Weather-Related Disasters in 1996

In 1996, Canadians suffered through some of the most extreme and destructive weather ever to have hit the country. For most of the year, the weather either froze, buried, soaked, buffeted or frightened Canadians. No part of the nation seemed to escape the wrath of the weather in 1996.

Total property damage will likely exceed $2.5 billion when the final figures are tallied. Indirect costs and losses from revenue shortfalls, canceled events, missed opportunities, and slowed business will probably be in excess of a $3 billion hit to the Canadian economy. Remarkably though, the number of personal injuries and fatalities linked to weather incidents could have been much higher. Unofficial numbers point to fewer than 25 weather-related deaths (excluding deaths from road accidents and hypothermia) - 10 from the storm in the Saguenay and six from lightning in separate incidents. The top weather stories of 1996 are:

The Saguenay Flood

By far the worst catastrophe of the year, and Canada's first billion dollar plus natural disaster, was the flooding and mud slides in Quebec's Saguenay River valley in mid-July. The storm produced the largest ever overland deluge in Canada this century - an amount equivalent to a two-month flow over Niagara Falls - triggering a surge of water, rocks, trees and mud that killed ten people and forced 12,000 residents to flee their homes. It was the deadliest flood since Hurricane Hazel in Toronto in 1954.

The scale of the tragedy was staggering. Many of the region's roads and bridges and delivery systems for power and water simply disappeared. To the insurance industry it was Canada's worst-ever weather disaster in economic losses. By including insured and uninsured losses and indirect costs to the economy, total losses are sure to exceed $2 billion.

The Pacific Storm of 1996

During the period December 22 to January 3, 1997 a series of brutal winter storms blasted Vancouver Island, the Lower B.C. mainland and the Fraser Valley with up to 85 cm of snow paralyzing infrastructure and commerce. The accumulation of snow for this series of storms was unprecedented in historical records of Vancouver Island and the lower south coast of British Columbia. The recorded 64.5 cm snow that fell in a 24 hour period, at the Victoria airport, gave Victoria the distinction of having the 3rd highest snowfall, in a major city, in Canadian history. During the same period, Downtown Victoria received 85 cm.

The environmental impact was severe in that massive releases of untreated of partly treated effluent were released into rivers and the ocean.

Although estimates of the economic losses range in the area of $200 million, the true impact of the storm will probably never be known. The following list suggests the overall impact

High Energy Costs

In much of Canada, 1996 featured one of the longest and most vicious winters in recent memory. Three straight weeks of frigid weather gripped almost the entire country in January making it colder in most cities in western and central Canada than it was at the North Pole. To keep up with the cold, utility companies pumped out power in record amounts from British Columbia to New Brunswick. Canadians paid an additional $500 million to keep their dwellings as comfortable as in the previous winter.

Costly Prairie Hailstorms

In July, hailstones the size of fists bombarded Winnipeg and Calgary, racking up close to $300 million in property losses. In Manitoba, more than half the losses were for auto damage, making it the worst single disaster claim against the Manitoba Public Insurance Corporation in its 25-year history. At least a third of the cars damaged had to be written off. In Calgary, hail and flooding rains knocked out the city's 911 service and swept away cars.

Wet and Cold Weather Reducing Crop Yields

Unfortunately for western farmers, prospects in early September for one of the most bountiful grain crops in Canadian history didn't exactly materialize. Fall temperatures across the west were much below normal (the Prairies had their second coldest fall in half a century) and precipitation was much above normal (the 7th wettest fall in half a century). Cool wet weather during the harvest of western red spring wheat led to a severe drop in its grade distribution, denying farmers an additional $180 million.

In southern Ontario, winter wheat production was severely affected by the wet cool weather throughout the growing season. Record rainfalls resulted in the worst outbreak of blight fungus ever seen in Ontario. According to Agriculture Canada, the excessive moisture and disease not only reduced yields, but it also reduced the quality of most of the crop to feed, since affected grain cannot be used for human consumption. The loss was estimated to be about $90 million.

Deep Winter Snows

So much snow fell early in the winter that before 1996 even started, many cities in western and central Canada had all but exhausted their snow removal budgets. Hardest hit was the central Ontario snowbelt from Barrie to Sault Ste. Marie, where on several occasions, cars disappeared in snow drifts, service centers became refugee camps, roofs collapsed and schools closed.

Insurance claims paid in the first three months of 1996 were 11% higher than in the previous year when the weather was much less severe. Total insured losses owing to the weather estimated at $165 million.

Slow Spring Affecting Retail Sales

For most of Canada, the winter season gave way to the monsoon season. Unrelenting rains and dreary weather plagued the country from April to June. Garden centers and golf courses were virtually empty during the spring. Retailers blamed the persistent cool and rainy weather for a 30% drop in the sales of weather sensitive goods and services, such as pools, air conditioners and warm season apparel. Sales of general merchandise in April and June were down by $100 million over the previous year's sales.

Flash Flooding in Ottawa and Montreal

The third major storm in less than two weeks, and the worst on record, hit Ottawa-Hull in early August with a deluge of 100 to 150 mm of rain in 90 minutes. Total insured property damage exceeded $20 million, not including the costs of repairs to damaged sewers and roads. Between November 7 and 9, thirty hours of steady rains drenched parts of Montreal and southwestern Quebec. The rains washed out sections of highways, collapsed bridges, derailed trains and undermined road and rail beds. Damage estimates put the event at over $60 million.

Severe Thunderstorms and Tornadoes

The snow had hardly melted in southern Ontario when the season's first tornadoes tore through regions east of Lake Huron in April. The twisters injured two people and caused property losses, much of it uninsured, approaching $8 million.

Severe thunderstorms on July 4 spawned at least eight tornadoes in Saskatchewan. Winds of 140 km/h and hail the size of golf balls produced $15 million in property damage. Two weeks later seven tornadoes touched down in Alberta, trashing trailers and flattening granaries to the tune of $10 million. Near Stoney Plain, more than 100 mm of rain fell in severe thunderstorms backing up sewers and flooding basements for another $10 million in losses. Tornado-related damage in Canada easily exceeded $50 million.

Spring Flooding

Significant flooding occurred in several communities across Canada during much of the spring and early summer. The Okanagan experienced its worst flooding in six years, The Red River inundated farm fields, roads and major highways leading authorities to declare a provincial flood disaster for the first time since 1979. In Winnipeg, the costs of filling 336,000 sandbags and protecting pumping stations alone cost $1.2 million. In Timmins, Ontario the Mattagami River overflowed its banks in the worst flooding across Canada and losses are still being tallied, with final figures are expected to range between $20 and $50 million.

Hurricanes and Weather Bombs

Four hurricane-force storms struck Eastern Canada in 1996: Bertha, Edouard, Fran and Hortense. It was the second consecutive season with above average hurricane formation in the North Atlantic. In 1996 there were 13 named storms of which 9 were hurricanes, including six intense ones, compared to a normal of 9 storms, 6 hurricanes and 2 intense ones.

Hortense, which swept east of Halifax and traversed western Newfoundland on September 14, was the first hurricane to achieve landfall in Canada in 21 years. Winds topped 161 km/h on cape Breton Island, felling trees, lifting roofs and blowing out windows. Total property losses approached $5 million.

Described as the worst storm since Typhoon Freda in 1962, a "weather bomb" struck Vancouver Island on October 17 causing massive power outages while felling trees, setting adrift 50 pleasure boats and ripping apart docks. A "weather bomb" is a storm which intensifies very quickly and moves faster than a hurricane. This storm packed winds as strong as 161 km/h and produced waves as high as 30 meters.


Are the number of weather-related disasters in Canada increasing? According to the Insurance Bureau of Canada, ever since the Edmonton Tornado of 1987, the number of multi-million dollar losses from weather disasters has been on the rise in Canada (note: before 1987 there was no single natural disaster with damages exceeding $1 billion anywhere in the world, let alone in Canada).

While the outburst of extreme weather was interesting, climatologists were not generally surprised by them. Climatologist are, however, becoming increasingly concerned that the volatile weather in 1996 might be a dry run of extreme conditions we might expect from a warming climate.

With this in mind, planners and decision-makers should note that natural hazards and disasters are expensive but not inevitable. With appropriate planning to reduce vulnerability, their social and economic impacts on Canadians can be reduced.

Societal Aspects of Weather

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