- In the summer of 1993, federal fisheries scientist John
Babaluk was on Banks Island, the most westerly of the big islands that
stretch across Canada's Far North, when some people showed him what had
come up in the nets they had set for Arctic char.
-
- No one in the tiny Inuvialuit community of Sachs Harbour
had ever seen such a fish, which wasn't such a surprise, considering that
it was 1,500 kilometres away from home. They had caught sockeye salmon,
normally found on the Pacific coast of British Columbia and Alaska.
-
- "We actually saw, recorded, took pictures and did
some measurements on some sockeye salmon that had shown up in Sachs Harbour.
That was the first time that any of the locals that we talked to had seen
them," Mr. Babaluk says.
-
- The itinerant salmon is just one of many strange sightings
across the country.
-
- The Far North is being introduced to the robin, the South's
harbinger of spring and a bird so rarely seen above the tree line that
the Inuvialuit don't even have a name for it.
-
- In Southern Ontario, the Virginia opossum now thrives
as far north as Georgian Bay. A few decades ago, it was unknown because
the climate was too cold.
-
- Wildlife biologists in Manitoba have noted that migratory
butterflies are returning earlier in the spring and that polar bears along
the province's Hudson Bay coastline are getting thinner because the sea
ice is melting earlier, giving the animals less time to fatten up on seals,
their main prey.
-
- Why is all this happening? There could be many explanations,
but the common thread through all the occurrences is that Canada's climate
has been getting warmer.
-
- That climate change might happen some day is hardly controversial.
Humans are adding more carbon dioxide and other planet-warming gases to
the atmosphere every year. Since the start of the Industrial Revolution,
concentrations of CO{-2}, the main greenhouse gas, have risen by about
30 per cent, but they will double by the end of this century if usage trends
for fossil fuels continue.
-
- Scientific models suggest that human-induced changes
to the composition of the atmosphere will almost certainly cause temperatures
to rise substantially over the next 50 to 100 years.
-
- But on the eve of another Earth Day, Canadians might
want to consider something more radical on the subject of global warming
-- directly from their own backyards. Warming should not be considered
an abstraction due to occur at some vague point in the country's future.
It has already arrived, and has been under way for the past few decades.
-
- A group of federal and provincial scientists have concluded
that global warming has had a profound influence on Canada after completing
the most exhaustive review ever undertaken of the hundreds of studies on
the country's climate trends. They looked at reports of unusual wildlife
sightings, such as Mr. Babaluk's salmon, the extent of glaciers on the
Rockies and data from weather stations going back more than a century.
-
- Except for small parts of the Northeast that have actually
become cooler of late, the warming is almost universal -- and not necessarily
just a momentary blip. "There are really strong indicators that the
climate is changing," says Environment Canada's Linda Mortsch, the
scientist co-ordinating the effort, "and I think Canadians should
be aware of that."
-
- That is why the researchers summarized their findings
in a 45-page report, published by the Canadian Council of Ministers of
the Environment and made public recently.
-
- The publication has not prompted the interest normally
associated with a major environmental review because the Winnipeg-based
council, which includes the federal, provincial and territorial environment
ministers, is little known outside environmental-policy circles. (It normally
works on such technical issues as the question of whether Canada should
regulate mercury emissions from power-plant smokestacks.)
-
- The climate change has been most dramatic in the North.
The Mackenzie Basin is now an average of two degrees warmer than it was
in the early 1950s, even though parts of Labrador, northern Quebec and
Baffin Island have grown cooler.
-
- But the best long-term temperature data are for the South,
and the report reveals that all of Canada below the line formed by the
northern boundaries of British Columbia, Alberta, Saskatchewan and Manitoba
has become warmer over the past 100 years.
-
- In fact, the average increase of 0.9 degrees in Southern
Canada is about 50 per cent larger than the rise that has occurred elsewhere
on the planet, making this country a global-warming hot spot.
-
- This has played out in some major temperature shifts.
-
- In Whitehorse, for instance, Environment Canada figures
show that the Yukon community used to have an average of 63 bone-chilling
days a year during the 1950s and 1960s when the mercury plunged to minus
20 or lower. By the 1980s and 1990s, that number had fallen to 49. The
same trend occurred in Yellowknife, where the number of extremely cold
days has fallen to an average of 108 a year from 121.
-
- And even though 0.9 degrees of warming may appear small
-- it's below the amount humans can feel through our senses -- it has had
some staggering environmental consequences.
-
- There has been a huge increase in frost-free periods
each year, as many gardeners probably suspect. In some areas, such as central
B.C., the span between the last frost in spring and the first freeze has
grown by a stunning 50 days over the past century, with healthy increases
also recorded on the Prairies and in Southern Ontario, Quebec and the Maritimes.
-
- The growing season is increasing mainly because the last
spring frosts are happening a little earlier each year -- a direct result
of nighttime temperatures that aren't falling as much as they used to.
-
- But garden ers shouldn't expect to plant tropical varieties
any time soon because the trend is unlikely to go on forever, says Joan
Klaassen, a climatologist at Environment Canada who has researched the
subject.
-
- "Eventually, we would have no winter," she
says, plus the length of the frost-free period is volatile. As recently
as 1980, for instance, Ottawa had its shortest growing season on record
-- a mere 110 days, compared with the maximum of 182 days posted in 1990.
-
- However, if the fluctuations are smoothed out, the frost-free
period has expanded by about 30 days since 1939.
-
- The trembling aspen, one of Canada's most common trees,
grows in all forested regions, and when springtime temperatures rise enough,
it goes into bloom. Aspens don't produce pretty flowers, but their date
of first bloom is like a weathervane pointing to dramatic global warming.
-
- In Edmonton, researchers at the University of Alberta
have been reviewing observations on the first flowering dates for the trees
from 1901 to 1997, and have found a huge change.
-
- While the trees went into bloom in early May at the beginning
of the last century, by its end, the average date had advanced by nearly
a month -- 26 days -- to early April.
-
- In the list of planetary threats, warming comes at the
top, or close to the top, of any motivating factors for Earth Day. Working
to preserve endangered species, cleaning up parks, and planting trees --
typical April 22 activities embraced by thousands of Canadians -- won't
mean much if the climate changes so dramatically that it plays havoc with
the planet.
-
- On paper, Canada has a good position on global warming.
It has endorsed the Kyoto Protocol and Prime Minister Paul Martin said
in February's Speech from the Throne that his government has unequivocal
support for the international pact to cut emissions of planet-warming gases.
-
- But the glaring weakness in the government's commitment
is that it hasn't fully explained how the country will meet the mind-boggling
240 million tonnes of emission cuts required to comply with the treaty.
-
- (To put the challenge of this abstract tonnage figure
in perspective, a typical car produces about four tonnes of CO{-2} a year.)
-
- One of the big worries about global warming is that melting
Antarctic and Arctic ice will cause sea levels to rise, inundating low-lying
coastal areas.
-
- Canada has the world's longest coastline, making it especially
vulnerable to flooding.
-
- For example, much of Charlottetown lies only a few metres
above sea level, and over the past century, the ocean has been slowly rising
up against the picturesque city.
-
- The total increase -- 30 centimetres -- means that now
even small storms maybe able to produce enough of a surge at high tide
to cause extensive damage.
-
- Researchers believe that about one-third of the rise
at Charlottetown has been caused by global warming and the rest from land
subsiding since the last ice age.
-
- Other areas at risk include parts of the GaspÈ
and the les-de-la-Madeleine in Quebec, along with parts of the Beaufort
Sea coastline in the Arctic.
-
- Most of British Columbia will be less affected by higher
sea levels because of its steep and rocky coastline, although low-lying
areas, such as the highly populated Fraser Delta, are vulnerable.
-
- Another dramatic sign of global warming is in Canada's
extensive glaciers and ice fields. Although not well known, this country
has more glacial ice coverage -- 200,000 square kilometres -- than any
place in the world, other than Antarctica and Greenland.
-
- The area of the most rapid warming in Canada in the past
50 years has been the West, and this heat has been cutting a swath through
glaciers. There are about 1,300 glaciers on the eastern slopes of the Rockies,
and they are 25 to 75 per cent smaller than in 1850.
-
- Elsewhere, alpine ice patches -- in reality, mini-glaciers
-- have been melting so rapidly from Yukon mountain ridges that archeologists
are having trouble keeping up with all the ancient artifacts being exposed
before these materials, such as carvings, wooden darts and leather pouches,
succumb to rot.
-
- A much bigger problem is that many major Prairie rivers
are fed by glaciers, so cities such as Edmonton, Calgary and Saskatoon
may face a thirsty future. Recent surveys have found that the amount of
glacier water feeding the Saskatchewan, the largest prairie river, has
already begun to drop.
-
- The arrival of salmon in the Arctic prompted a lot of
head scratching at the federal Fisheries Department, and led to an investigation.
Was the sighting a result of global warming or just wanderlust?
-
- The salmon have kept coming since 1993 -- several were
found last year -- but researchers also have gone through historical records
and found sporadic visitations in the past.
-
- Federal fisheries scientist Sam Stephenson has studied
the situation and says he still isn't sure whether the salmon are just
looking for new territory to conquer or have been pushed north by warmer
water temperatures in the south. "I would be hesitant to say global
warming at this stage," he says, adding that "certainly, this
is something that bears watching."
-
- However, something happening on neighbouring Victoria
Island is even more difficult to explain. Mark Ekootak, a wildlife officer
for the Northwest Territories government, was surprised by the recent arrival
of something "I've never seen growing up" on the barren tundra.
-
- Only by consulting a field guide did he finally figure
out that he had a tree swallow on his hands -- a bit odd considering that
the tree line lies 750 kilometres to the south.
-
- Martin Mittelstaedt is The Globe and Mail's environment
reporter.
-
- LOCAL WARMING: CHANGES FROM COAST TO COAST
-
- Pacific Ocean
-
- Water temperatures off the B.C. coast have risen
- substantially in the past 100 years.
-
- Mackenzie River
-
- Salmon have begun to appear.
-
- Mackenzie Basin
-
- Average temperatures have increased two degrees over
- the past 50 years.
-
- Mackenzie Delta
-
- Received its first-ever tornado warning in 2001.
-
- Western Arctic
-
- The area covered by permanent sea ice has fallen 25
- per cent since 1969.
-
- Rocky Mountains
-
- The 1,300 glaciers on the eastern slopes are 25 to 75
- per cent smaller than in 1850.
-
- Banks Island
-
- There have been sightings of robins, a bird so are in
- the Arctic that it has no name in the local Inuvialuit
- dialect.
-
- Central British Columbia
-
- The growing season is 50 days longer than it was 100
- years ago.
-
- Edmonton
-
- The trembling aspen now blooms in early April compared
- with early May in 1900.
-
- Prairies
-
- Average temperatures have risen 1.5 degrees over the
- past 100 years.
-
- Saskatoon
-
- The number of blizzards has fallen sharply since 1953.
-
- Manitoba
-
- Butterflies are appearing up to 12 days earlier in
- spring than they did 30 years ago.
-
- Western Hudson's Bay
-
- Fat levels in polar bear shave been falling since
- 1980.
-
- Hudson Bay
-
- The ice-free season is more than a week longer than it
- was 30 years ago.
-
- James Bay
-
- The Arctic white fox is disappearing from the southern
- part of its historical range.
-
- Great Lakes
-
- Average water temperatures have risen 0.5 degrees over
- the past 100 years.
-
- Lake Simcoe
-
- Winter ice coverage is much briefer than in the past.
-
- Arctic
-
- Thunder and lightning, once very rare in the Far
- North, are now being experienced fairly often.
-
- Southern Ontario
-
- The Virginia opossum, unknown in the area until the
- 1980s, now thrives as far north as Georgian Bay.
-
- Southern Canada
-
- Receives as much as 30 per cent more precipitation
- than it did in 1900.
-
- Quebec
-
- The city of Drummondville has found that the heating
- requirements have fallen notably in recent years while
- the demand for air conditioning has risen.
-
- Charlottetown
-
- Over the past century, the sea level at the city has
- risen by nearly 30 centimetres, increasing the risk of
- flooding during a storm.
-
- © Copyright 2004 Bell Globemedia Publishing Inc.
All
- Rights Reserved.
-
- http://www.theglobeandmail.com/servlet/story/RTGAM.
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