Global Warming & Climate Change

1. Global Warming & Climate Change A Canadian Perspective

2. “The ultimate concern is that if runaway global warming occurred, temperatures could spiral out of control and make our planet uninhabitable... this is the first time that a species has been at risk of generating its own demise.… The dinosaurs dominated the earth for 160 million years. We are in danger of putting our future at risk after a mere quarter of a million years.” (Michael Meacher, UK Minister for the Environment 1997-2003, The Guardian

3. Unfortunately we are not just hurting ourselves.

5. “Climate change is a global challenge that demands a global response. Yet there are nations that resist, voices that attempt to diminish the urgency or dismiss the science, or declare, either in word or indifference, that this is not our problem to solve. Well, let me tell you, it is our problem to solve... To the reticent nations, including the United States, I say this: There is such a thing as a global conscience.” (Canadian Prime Minister Paul Martin, quoted in the L.A. Times)

6. This ‘drunken forest’ is the result of the loss of permafrost in the tundra biome.

7. Climate is an average of weather over a long period of time in a given place. The Earth's natural climate is constantly changing, and in the first few hundred million years of Earth's formation, temperatures far exceeded what they are now. Dramatic changes from the tropical conditions of the Earth associated with the existence of dinosaurs to the ice ages have been natural throughout Earth's history.

8. The following graph shows the variation of global mean temperatures from 1880 to 2006 relative to the mean temperature during the base period from 1951 to 1980. What trend does the chart illustrate? Would the magnitude of the trend increase or decrease if annual mean temperature was plotted against a base period from 1881 to 1910? Consider how the base period that is selected impacts on the visual presentation of the data.

11. The Greenhouse Effect Did you ever get into a car after it sat in the sun with the windows closed? Even if the sun is out on a cool day, the car will heat up. This is because of the greenhouse effect. The greenhouse effect is a heat-trapping process that occurs naturally in the atmosphere. Incoming energy from the sun penetrates the atmosphere to warm the Earth. The planet then radiates heat back out toward space. Some of the outgoing heat is absorbed by greenhouse gases in the atmosphere and re-emitted back to the Earth.

12. Greenhouse gases (GHGs) are gases in the atmosphere that increase the greenhouse effect (capable of absorbing the infrared radiation emitted by the Earth). Some of the GHGs are human-made from the combustion of fossil fuels for cars or from producing heat and electricity and some are naturally produced in the environment.

13. The Greenhouse Gases: • Carbon Dioxide (CO2) is produced by the combustion of fuel, deforestation, and industrial processes. It is also produced naturally in the environment through the decay of organic matter and respiration by living things. • Methane (CH4) is produced in livestock and rice cultivation, in biomass burning, and in the decomposition of landfills. Methane release also occurs naturally in wetland areas. Methane exerts 21 times the greenhouse effect of CO2. • Nitrous oxides (N2O) are produced in the burning of fossil fuels, wood combustion, and the production of nitrogenous fertilizers; anaerobic bacteria in the soil also naturally produce it. Nitrous oxides exert 310 times the greenhouse effect of CO2. • Hydrofluorocarbons (HFCs) are found in sources including foam insulation, metal production, and coolants in refrigerators and air conditioners; they are not produced in nature. HFCs exert 140 to 11 700 times the greenhouse effect of CO2. • Perfluorocarbons (PFCs) are found in sources including aluminium production, refrigeration, and air conditioning; they are not produced in nature. PFCs exert 6 500 to 9 200 times the greenhouse effect of CO2.

14. Something to think about… • The greenhouse effect is critical in providing conditions suitable for life on Earth. Without it, the Earth's average temperature would be −19°C instead of 14°C. Conversely, too much CO2 could result in conditions such as on Venus that result in the temperatures exceeding 400° C or like on Mars whose thin atmosphere lacks GHGs and creates an environment too cold to be suitable for life. • The atmosphere is only composed of 0.03% carbon dioxide, and levels of CO2 have increased by 30% since 1700. The main source of carbon dioxide appears to be the burning of fossil fuels. • In order to stabilize atmospheric concentrations of greenhouse gases where they are today, global CO2 emissions would have to be cut by 50 to 60%.

16. Canada has experienced warmer average temperatures with a 1.4° C increase from 1948 to 2007. The northern and arctic areas experience the coldest and driest weather in the country, and global warming is expected to impact them the most. The temperatures have already increased by 2.1°C in both the Yukon/North British Columbia mountains region and the Mackenzie District. The following map indicates a greater increase in temperature in the northern arctic regions.

17. Climate change will affect all Canadians regardless of location. The impact will not just be on the environment but also on the economy and human health. The impact will vary regionally, and although there are disagreements in climate models as well as the cause and effects of global warming, there is a general agreement that changes have begun to occur and future changes are inevitable.

18. Expected changes in Canada include: • warmer winters; • tree line and wildlife species shift to the north; • more frequent heat waves; • changes in general weather patterns (precipitation, winds, and temperature); • permafrost melting in the arctic; • increased frequency of storms; • glaciers retreating; • greater risk of icebergs off the coast of Labrador; • arctic sea ice melting • changes to Inuit way of life and opening up year round ice free shipping routes; • sea levels rising; and • more severe drought conditions in the Prairies and B.C. leading to a loss of crops and forest wildfires.

19. Whitechuck glacier in the North Cascades in 1976 and 2006

21. Albedo feedback effects • Albedois the proportion of incoming solar radiation reflected from the earth back into space. It depends on many factors, including the colour and roughness of the terrain. Clouds, ice and snow reflect a greater proportion of radiation than do bare land and ocean surfaces, which tend to absorb this radiation. • Decreasing snow and ice cover leave greater areas of bare earth and ocean surface to absorb solar radiation, thereby contributing to continued and accelerated warming.

22. Socio-economic impact of reduced snowpack and melting glaciers Much of western Canada, particularly the driest regions in the southern Prairies, is heavily dependent on snowmelt and glacier runoff for stream-flow. Glacier-fed rivers reach peak stream-flow during the hot summer months, reducing variability in flow during periods of low precipitation. These rivers are an important source of water for community, agricultural and recreational activities. Reduced stream-flow could result in water shortages during periods of peak summer demand.

23. Agriculture in southern Alberta and in parts of Saskatchewan and British Columbia relies heavily on irrigation. The three provinces used over 4.2 billion cubic metres of water to irrigate crops in 2001, 96% of all irrigation in Canada. Stream-flow variability is a risk for the hydro power industry and lower water levels in rivers and lakes will challenge the health of freshwater fisheries. Rising sea levels as a result of thermal expansion of sea water and the melting of glaciers, ice caps and ice sheets are expected to contribute to flooding and erosion of coastal areas

24. Sea ice Sea ice controls the timing and amount of maritime activity in Canada's eastern and northern waters. Arctic waters are normally covered by solid pack ice throughout the winter, while summer break-up signals the opening of the shipping season. Arctic sea ice has experienced enhanced summer break-ups over the last few decades, adding to evidence of warming near the North Pole. In September 2007, sea ice throughout the circumpolar region shrunk to its lowest level since satellite measurement began.

26. In the Canadian Arctic, the summer of 2007 was a year of very low sea ice coverage, but did not set record minimums. Ice conditions are highly variable on a year-to-year basis; however, satellite observations indicate that the extent of sea ice has declined since 1969 and submarine measurements indicate Arctic ice thickness diminished by 40% from 1961 to 2001.

27. Evidence shows that the length of the navigation season is increasing marginally in the Canadian Arctic while sea ice is decreasing. The cost of shipping could be reduced if the Northwest Passage were ice-free for longer periods in the summer, allowing shorter routes between Europe and Asia. Longer shipping seasons could also improve access to remote communities and mines, to deliver supplies and retrieve goods and ore for export.

28. Other impacts affecting society and the economy • Climate change will have profound effects on Canada's natural resources and ecosystems. Biodiversity, the variability of life forms within a given ecosystem–including both marine and terrestrial systems–will also be affected. • These changes to Canada's climate will have beneficial and adverse effects on society and the economy. Although the costs and benefits are hard to quantify–lower costs to heat homes and buildings as a result of warmer winters may be offset by increases in air conditioning in the summer–changes are more likely to be negative if climate change is severe and occurs rapidly than if it is moderate and progresses gradually, allowing time for Canadians to adapt.

29. With warming temperatures, species and habitat will shift north, move to higher elevations and even disappear. Boundaries between forest and tundra ecosystems are expected to advance in altitude and latitude in response to climate warming. Climatic limits for agricultural crops will also shift, though soils in more northern regions may be less suitable for agriculture. • A longer growing season and increasing levels of CO2 could increase the productivity and yields of agricultural crops and timber forests. However, water shortages resulting from changes in the timing and amount of precipitation could limit yields, especially in the already drought-prone Prairies. Pest problems could also become more severe. • Range shifts in pests have already had a large impact on the forestry industry. In British Columbia, the spread of the mountain pine beetle in the central interior of the province has coincided with warmer winter extremes.

30. Mountain Pine Beetles • Mountain pine beetles prefer mature (80 years or older) lodgepole pine and kill trees by laying their eggs under tree bark. The developing larvae eat the tree's phloem, cutting off the supply of nutrients. The beetles also transmit a fungus that stains wood blue. • Cold winter temperatures of -35°C to -40°C over several days will kill a large proportion of the beetle population; however, the mild winters and dry summers of recent years have allowed beetles to thrive in British Columbia. As temperatures rise, climate may no longer present a barrier limiting the range of mountain pine beetles to British Columbia. Beetles have recently moved into parts of western Alberta and concern is growing that they will spread across the Prairies and eastern Canada. Jack pine, a major component of the boreal forest, is a viable host tree for the beetles.

31. And there’s more… Warmer summer temperatures can also enhance the formation of ground-level ozone and lead to increases in emissions of air pollutants–through the greater use of air-conditioning systems, for example. These air pollutants affect human health, especially for those with allergies, asthma and respiratory disorders. Nationally, exposure to ground-level ozone increased an average of 0.8% per year from 1990 to 2005.

32. “Our emotional, spiritual and cultural well-being and health depend on protecting the land. We cannot find our way with band-aid solutions. For Inuit, the environment is everything. “ (Sheila Watt-Cloutier)

33. Dealing with climate change: • The Kyoto Protocol is the world's primary agreement on trying to reduce global warming. More than 160 countries have signed the agreement; however the United States, the largest greenhouse gas producer, has yet to ratify the treaty because they feel that it is unfair that large population centres such as China and India have been exempted because they are classified as developing countries. In 2002, Canada ratified the Kyoto Protocol and committed to lowering GHG emissions to 6% lower than the 1990 GHG emissions (estimated at 596 megatonnes) by 2008-2012. However in that time the emissions had increased by 25%, and in 2005 the emissions were at 747 megatonnes – 32.7% above the Kyoto target.

34. Two strategies for dealing with climate change are: • Adaptation: This is the response to the changing environment by reducing our susceptibility to the impact of climate change. For example the location of activities such as ice fishing can be changed. • Mitigation: This is the active effort made to reduce GHG emissions locally and globally.

36. Governments at all levels are contributing to reducing emissions by providing financial support for the development of many initiatives such as: Governments at all levels are contributing to reducing emissions by providing financial support for the development of many initiatives such as: • Encouraging Canadians to use energy more efficiently through more energy-efficient buildings. • Developing renewable energy and clean energy technologies. • Offering rebates for residential energy-saving equipment. • Offering rebates on energy saving products (e.g., hybrid cars and LED Christmas lights). • Encouraging and promoting the use of public transit. • Regulating the amount of GHG emissions from industries. • Setting an example by increasing efficiency of government buildings and reducing emissions from their vehicles.