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Global Warming. What Does It Mean? Impacts of Climate Change. Main Findings of IPCC-WG I. Human activities are changing the atmospheric concentrations of greenhouse gases.
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Global Warming What Does It Mean? Impacts of Climate Change
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.
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
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.
Permafrost in Canada Present 2xCO2
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.
Rising Seas: The Future • One of the most striking consequences of global warming will be the associated rise in global mean sea level.
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.
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.
What to do? • Human influence on climate will continue to grow during the next century unless measures are taken to reduce GHG emissions.
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."
Slowing Global Warming • Reduce emissions - the quickest, cheapest, most effective way to reduce emissions is to use energy more efficiently.
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.
Kyoto Targets Australia 8 Canada -6 European Union -8 Iceland 10 Japan -6 New Zealand 0 Norway 1 Poland -6 Russian Federation 0 United States -7
How much will the Kyoto Protocol reduce emissions? Data Sources: United States Department of Energy, Energy Information Administration, International Energy Outlook, 1998 and 1999.
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.