FACTS ABOUT IMPACTS

IMPACTS OF CLIMATE CHANGE

Global Meltdown
Glaciers,ice sheets at risk

Glaciers, ice sheets and arctic ecosystems will be severely affected by climate change. Glaciers around the world are already shrinking, threatening wildlife and freshwater supplies. Global climate models predict extreme warming in the arctic if greenhouse gas emissions continue to rise. Meanwhile, warmer ocean temperatures will transport large amounts of heat to coastal Antarctica. Local impacts will be severe, but these changes will be felt throughout the world.

In the arctic, warmer temperatures will bring a loss of sea ice and permafrost, disrupt ecosystems and traditional lifestyles, as well as wreak havoc with modern infrastructure.

Enormous land-based ice sheets perched near the poles appear to be vulnerable to human-caused climate change. If these ice sheets collapse, adding their bulk to the oceans, sea level could rise by many metres in a matter of centuries.The extraordinary Canadian alpine wilderness is threatened by climate change. Ecosystems will undergo severe upheaval, challenging their ability to adapt, while shrinking snowpack will reduce the freshwater supplies humans depend on.

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Extreme Weather

Throughout the 10,000 year history of human civilization, weather patterns have remained relatively constant. Though floods, droughts, storms and other extreme weather events have always been a reality, they have been rare occurences interrupting long periods of calm - sudden outbursts of violence marring a gentle rhythm.

Now, because of human induced climate change, that gentle rhythm is breaking up.
The frequency of extreme weather events has increased steadily over the 20th century. The number of weather-related disasters during the 1990s was four times that of the 1950s, and cost 14 times as much in economic losses. One in five Canadians was directly affected by a weather disaster between 1996 and 2000.
These trends confirm the predictions of computer models:

as the atmosphere warms, the climate will not only become hotter but much more unstable.

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Extreme weather events on the rise

Severe winter storms:

Since the mid 1970s, the frequency of severe winter storms in Canada has nearly doubled. Models predict that future winters will boast fewer weak storms, but increasing numbers of very severe storms. This means more travel disruptions, more property damage and more accidental deaths.

Downpours:
In the USA, heavy one-day rainfalls have become 20% more common over the past 90 years. These cause flooding of city streets, sewer overflows, erosion, flash floods and landslides, without the benefits of recharging reservoirs or alleviating drought. Canadian models suggest that within 50 years, heavy one-day rainfalls will become twice as common as they are today, and are also likely to become 50% more intense.

Heat Waves:
Both the frequency and length of heat waves are expected to increase in most parts of the world. Temperatures which have been "extreme" for generations will become "normal".
As an example, the number of days with temperatures over 30ºC in London, Ontario is expected to rise from 10 days per summer to about 50 days per summer by 2050. August in the Toronto of the future will probably be much like that of Kentucky today.
These periods of intense heat will amplify smog, already a significant cause of death (see Pollution Worsens) and heat-related death tolls will spiral upwards.

Hail:
In Calgary the average frequency of large hailstorms (hailstones greater than 20 mm) has increased eightfold, from one every four years in the 1980s to two per year in the 90s. As the frequency of hail-generating thunderstorms is expected to increase dramatically, so will the damage to cars, buildings, and agricultural crops.

Tornadoes:
An increase in warm, moist lower atmosphere conditions will spawn large tornadoes more frequently - such as the recent event that devastated Pine Lake, Alberta. Central Alberta, southern Ontario and the Ontario/Quebec border will probably experience the strongest rise in these violent events.

Wildfires:
Over the past several decades, the area of Canadian boreal forest affected by fire and insects has doubled. Although there are complex factors involved, the greatest increases so far have been in the regions of greatest warming. Continued warming will produce greater seasonal contrasts which, in concert with an expected 44% increase in thunderstrikes, is expected to increase the area burned by 78% in the next 50 years.

Unconventional Catastrophes:
The Ice Storm of 1998 was a taste of the nasty surprises climate change could hold in store for Canada. It was not a severe storm in normal terms - in fact, the scene on the ground was a peaceful, gentle drizzle. It was the incredible duration and extent of the drizzle that made it, at a total of $3 billion, the most costly natural disaster in Canadian history.

Why would global warming make an ice storm?
There is good reason to believe that the Ice Storm, which generated ice twice as thick as had ever been recorded before in the region, would not have been possible without the 1997-98 El Niño The El Niño Connection. This unprecedented El Niño, in turn, was probably born of climate change.

The El Niño produced an unusually strong jetstream across the southern US, which then swung up to carry a long train of warm, moist air masses to eastern Canada. At the same time, a shallow layer of cold air crept down from Labrador and stalled in the St. Lawrence Valley. The warm air rode up on top and dropped rain into the cold surface air, so that it froze on contact with the ground. The stability of the El Niño-driven jetstream maintained what would normally have been a shortlived scenario for many days - turning a rainy afternoon into a week-long multi-billion dollar disaster.

As global weather patterns continue to change, bizarre weather - like that which caused the ice storm - will become more common. New weather patterns, combined with other climate change impacts (such as sea level rise and rapid snowpack melts), will generate unexpected new types of disasters.

And as the disasters mount, so do their price tags.

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Imperilled Ecosystems

Climate change is altering the patterns of life on the planet, and scientists have already blamed it for species extinctions, migrations and behaviour changes. Disproportionately large temperature rises in northern latitudes mean countries like Canada will experience some of the most serious impacts on biodiversity.

A changing climate forces plants and animals to migrate in order to survive. However, research has shown that most plant species are able to migrate at only one tenth of the speed required to keep up with human-induced climate change.
To make matters worse, human settlements and infrastructure have already subdivided ecosystem habitat into isolated patches. Climate change will make many of these patches uninhabitable for the species which live there, and they will be unable to escape.

Signs of climate stress are already apparent among wildlife:

• Scientists view climate change as one of the causes of a dramatic drop in Pacific salmon populations along the west coast of North America.
  
  
• In 1999, scientists blamed global warming induced climate change for the disappearance of 20 Costa Rican frog species.
  
  
• British birds are laying their eggs earlier due to warmer springs in the last 20 years. Researchers worry this may affect survival, if food such as insects are not available when chicks hatch.
  
  
• In Europe, butterflies have shifted their boundaries north over the past 30 to 100 years, and rising temperatures are killing them at the southern extreme of their ranges.
  
  
• Canada's increasingly dry Northern boreal forests, stretching across the Canadian shield, have seen burns go from 1 million hectares to 3 million in the last decade.
  
  
• Female caribou migrate in spring to small pockets of vegetation where they feed and raise their calves. But for the last 10 years, spring has come so early that by the time the caribou reached the coastal plain, their principal food plant had already gone to seed.
  
  
• A receding Arctic icecap and earlier than normal breakup of sea ice has affected polar bears, which depend on sea ice to hunt seals. Recent studies showed polar bears in some regions were down a third in body weight. The latest generation of seals was also found to be much thinner than usual.
  
  
• Global warming has also affected the prey of killer whales off the coast of Alaska. They now resort to hunting sea otters since sea lions and harbour seals are absent from their range. Scientists say the sea lions and seals have moved away because global warming has altered fish migration patterns. The loss of sea otters sets off a chain reaction that destroys kelp beds, an important habitat for many ocean species.
  
  
• Recent research has led scientists to predict that global warming could eliminate coral from most areas of the world by 2100. These abundant ecosystems are home to a fourth of all marine fish species. In 1998, record sea temperatures triggered the largest mass die-off of coral in modern times. The impact of global warming on Australia's Great Barrier Reef is expected to become severe by 2050.

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HEALTH

Human health will be strongly impacted by climate change.
As climate change brings tropical weather to higher latitudes, tropical diseases - like the West Nile virus - will follow. Ecosystem disruption will make the outbreak of water-borne diseases more likely.
Air pollution, is already a scourge on public health. Climate change will make smog more intense, and lead to still higher rates of asthma and heart disease.
The most devastating casualties will be among inhabitants of poor countries, where there is little infrastructure to deal with changing water tables and increased extreme weather. Among the world's least privileged, the potential for climate induced disaster is enormous.

Deadly Heat
Climate change will cause high latitude regions, like Canada, to warm drastically. With tropical heat comes tropical illnesses, and large increases in heat-related deaths.
Heat can aggravate health problems, particularly for the old, the young and the ill. For example, Montreal currently has approximately 70 annual heat-related deaths, while Toronto has 20. According to the World Health Organization, these figures are expected to climb to 460 and 290 respectively by 2020 due to climate change.

A hotter world is a sicker world
Rising average temperatures will likely extend the ranges of disease-carrying organisms like mosquitoes, rodents and bats. In 1998, drought followed by heavy rains in western North America led to a sharp increase in the population of deer mice, which carry hantavirus.
The West Nile virus has entered the United States and is moving northwards as the continent warms.
Disease-causing tropical plants have also begun migrating northward. A tropical fungus invaded Vancouver Island in 2002, killing one and injuring 52.
Global warming may also increase the risk of respiratory diseases because grasses and allergenic pollens grow more profusely in a warmer environment. A 2002 study showed that ragweed - a potent allergen producer - grew up to 61 per cent faster under conditions expected by 2050.

· Air Pollution
According to the Government of Canada, air pollution prematurely kills at least 16,000 Canadians each year. Recent studies show that close to eight per cent of all non-traumatic mortality in Canadian cities is attributable to air pollution.
Burning fossil fuels is the main cause of both air pollution and climate change, and scientists believe that climate change will actually make air pollution an even greater health threat - unless fossil fuel emissions are drastically reduced.

Ground level ozone
Ground level ozone is the nasty cousin of stratospheric ozone. Whereas stratospheric ozone (the "ozone layer") protects plants and animals from ultraviolet radiation, ground level ozone is a primary ingredient of smog. Higher temperatures increase ground level ozone production - thus climate change will intensify urban smog.
Ozone is toxic at low concentrations and deadly at high concentrations. It bursts cell membranes in the lungs, and as cellular fluids build up, breathing becomes more rapid, shallow and painful. The elderly and children are especially vulnerable, and ozone can lead to lifelong damage as lungs stiffen and scar. Ozone also sensitizes the airways to irritants and other allergens. Elevated ozone levels mean more hospital admissions for asthma, respiratory disease and acute respiratory disorders.

Toxic Brew
Air pollution from burning fossil fuels produces many other compounds that hurt our health: carbon monoxide, nitrogen oxide, sulphur dioxide, volatile organic compounds, and small airborne particulates. They can cause impaired lung function, shortness of breath, wheezing, asthma attacks and premature death.
Air pollution is also the primary culprit behind rising levels of asthma. A recently published 10-year study of Southern California communities showed that children living in smoggy areas were three to four times more likely to develop asthma than those living in cleaner areas.
By reducing our use of coal, oil and natural gas, we can save thousands of lives and lessen the threat to human health of both climate change and air pollution.
For further information, see the book A Citizen's Guide to Air Pollution and the report Taking our Breath Away: The Health Effects of Air Pollution and Climate Change

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ECONOMIC IMPACTS, Rolemodel: Canada

The Intergovernmental Panel on Climate Change predicts damage caused by climate change could cost developed countries up to 2 per cent of GDP. For Canada, a country highly dependent on natural resources, this figure would likely be much larger.
We're already seeing ominous changes:

• Rising ocean temperatures on Canada's West Coast have weakened economically valuable salmon species, reducing the survival rates of spawning fish, scientists say. During the 1997 Fraser River sockeye run, mortality rate was 76 per cent, compared with a typical average of 5 per cent.
• Forests in British Columbia were devastated in 2001 by the spruce pine-beetle, which thrived thanks to unusually mild winters. An estimated 500,000 hectares of timber worth $4.2 billion was infested, according to the BC ministry of Forests.
• The 2001 prairie drought cost the Canadian economy over $5 billion in agricultural losses, according to a University of Manitoba study.

In the future, Canadians may also expect the following:

• Increased forest fires could turn large portions of Alberta's aspen parkland and boreal forest into grass and shrubland.
• Higher temperatures, dryer soil and increased insect infestation are expected to reduce crop yields in much of the prairies by up to 30 per cent, according to Environment Canada studies.

Internationally, insurers are feeling the costs of climate change. Before 1988, the global insurance industry never had claims for more than US $1 billion in any single natural disaster. Yet between 1988 and 1996, 15 such events occurred, and a number of insurance companies closed down in the wake of these disasters.
According to the Munich Reinsurance Corporation of Canada, "Economic losses caused by natural catastrophes are likely to bring home the effects of climate change more and more dramatically as time goes by."
Nonetheless, economic opportunities can be found among the solutions to climate change.

 

**The content of these pages are taken from www.davidsuzuki.org, an excellent website about the environmental issues founded by Dr. David Suzuki Foundation from Canada.