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Global Warming
What Does It Mean?
Impacts of Climate Change
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Main Findings of IPCC-WG I
• Human activities are changing the atmospheric
concentrations of greenhouse gases.
• There is extensive and widespread evidence that the Earth
is warming; we are already seeing the first clear signals of
a changing climate.
• There is new and strong evidence that most of the warming
observed over the last 50 years is attributable to human
activities.
• Global temperature will rise from 2.5 to 10.4°F over this
century. Precipitation patterns will change, sea level will
rise and extreme weather events will increase.
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Feeling the effects
• In Canada we are already feeling the effects
of climate change:
– increasing number and intensity of heat waves
– hotter summers and higher level of smog in
major cities
– declining water levels in the Great Lakes
– melting of polar ice
– insect infestations in BC forests
– changes in fish migration patterns
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Forest Fires in Canada
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Temperature
change:
Canada and
the Globe
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Canada: Temperature Changes
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Change in Arctic Ocean:
Summer Ice Cover
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Arctic Sea Ice
• Sea ice extent has
been declining
since the 1970s
and there has
been an increase
in the length of
the summer melt
season.
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Global Sea Ice Extent , 1900-2000
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Climate, Productivity and Habitat
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Habitat and Productivity
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Ecozones
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Permafrost in Canada
Present
2xCO2
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Changes to Permafrost
At present, the permafrost regions
extend over about 48% of the
Canadian land mass.
• Cold stable permafrost makes
up 47% of permafrost.
• Warm unstable permafrost
comprises 33% of the total.
Under 2xCO2 warming, it is estimated
that the permafrost regions in Canada
would be reduced to 21% of the land
mass - less than half its present extent.
• Cold stable permafrost would be
reduced the most (to only 37%).
• Warm unstable permafrost
would comprise 38% of the total.
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Rising Seas: The Future
• One of the most
striking
consequences of
global warming
will be the
associated rise in
global mean sea
level.
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Delaware Bay
Over the next century,
sea level is most likely
to rise 55-60 cm along
most of the U.S.
Atlantic and Gulf
Coasts.
The 3.5-meter contour
roughly illustrates an
area that might be
flooded over a period
of several centuries.
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Sea Level and Coastal Erosion
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Other Impacts of Climate Change
• A changing climate will strongly influence
the pattern of agriculture, level of
biodiversity, availability of water, spread of
human disease organisms and the intensity
and frequency of severe weather events.
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http://www.ec.gc.ca/climate/ccs/ccs_e.htm
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What to do?
• Human influence on climate will continue
to grow during the next century unless
measures are taken to reduce GHG
emissions.
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Agenda 21: Climate Action
• Recent trends show that global emissions of
greenhouse gases continue to rise, and are
not expected to abate in the absence
government imposed controls.
– The 1992 Framework Convention on Climate
Change established the objective of stabilizing
atmospheric concentrations of greenhouse gases
"at a level that would prevent dangerous
interference with the climate system."
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Slowing Global Warming
• Reduce emissions - the quickest, cheapest,
most effective way to reduce emissions is to
use energy more efficiently.
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Kyoto Protocol
• The Kyoto Protocol to the Framework
Convention on Climate Change, negotiated
by over 160 countries in December 1997.
– The agreement would require 38 industrialized
countries to reduce the emissions of six major
greenhouse gases by an average of 5.2 percent
during the 2008-2012 period.
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Kyoto Targets
Australia
Canada
European Union
Iceland
Japan
New Zealand
Norway
Poland
Russian Federation
United States
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8
-6
-8
10
-6
0
1
-6
0
-7
How much will the Kyoto Protocol
reduce emissions?
Business-as-usual
Kyoto Protocol scenario
Billion tons of carbon
8
6
8.0
7.6
6.4
5.8
4
2
0
1990
1995
2000
2005
Data Sources: United States Department of Energy, Energy Information Administration, International
Energy Outlook, 1998 and 1999.
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2010
How Effective is it?
• According to global carbon emission
projections, even with the agreement,
emission levels in 2010 are still expected to
be more than 30 percent higher than 1990
levels.
– The emission cuts by industrialized countries will
be more than offset by emission increases from
developing countries that are not bound by
emission limitations under the Kyoto Protocol.
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