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Chapter 17:

Chapter 17:. Environment. Population and Resources. 80 million babies born every year Mostly in developing world, so less impact 20% of population consume 85% world ’ s resources 20% is in Industrialized western countries

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Chapter 17:

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  1. Chapter 17: Environment

  2. Population and Resources • 80 million babies born every year • Mostly in developing world, so less impact • 20% of population consume 85% world’s resources • 20% is in Industrialized western countries • If small fraction of developing world lived like developed world, Earth would quickly be overwhelmed with pollution and waste http://www.royalsaskmuseum.ca/gallery/life_sciences/footprint_mx_2005.swf Your footprint! http://www-popexpo.ined.fr/eMain.html

  3. Maintaining economic growth without compromising the environment. • Focus of the 1987 Bruntland Commission (aka: UN Commission on the State of the Environment). • Called on developed world to reduce consumption & practise sustainability • Called on developing world to reduce population growth • Canadians look to gov’t to take action, but gov’t and international actions have not been as successful as hoped • 1992 Earth Summit in Rio De Janeiro, Brazil produced statement of action called Agenda 21 • Intended to encourage development of sustainable world economy • Over 10 years later, little progress has been made Sustainability

  4. Water: The Indispensable Resource • Value of fresh water underrated • 3% of world’s water is fresh water • Is enough to supply the world, but distribution is unequal. • 78% of that locked in ice caps and glaciers • Remainder is underground (ground water) • Great Lakes = 18% world’s surface fresh water • Developed nations known for water waste and pollution

  5. Groundwater supply threatened by: • Increasing population • Diversions of surface supply (agriculture) • 40% world’s harvests come from irrigation • USA, China & India facing reduced g.w. supplies • These three nations produce ½ the world’s food • Last ½ 20th C, amount of irrigated land more than doubled (over 250 million hectares) • Farmers had better technologies to access groundwater • Access water in “Aquifers” Abusing Groundwater

  6. Threats to Water Quality and Supply • Groundwater Depletion • Over pumping of aquifers (underground layer of water-permeable rock) which replenish slowly reduces the water table (top of saturated layer of porous rock – ground water)

  7. Water supply is cheap and reliable • Once depleted, takes long time to recharge • North China Plain where most China’s food produced, water table falling 1.5 m per year • India’s water tables falling 1-3 m per year and could reduce India’s harvest by 25%, making India more dependent on imported grain • USA’s Ogallala Aquifer = world’s largest, supplies 1/5 USA’s irrigated land. Filled over thousands of years by runoff from Rockies. • In 50 years, reduced by 50% • US gov’t allows “groundwater depletion” as tax write off for farmers…so much for conservation! Aquifers

  8. Lakes, Rivers & Coastal Waters • Disposal for sewage & agricultural + industrial waste • Tanker accidents • Municipal waste water=human waste, detergents & solvents • Farmers = herbicides & pesticides • Industry=oil refinery, pulp mill & chemical factory waste Abusing Surface Water

  9. Threats to Water Quality and Supply in Canada • Misuse • 19% fresh water used for industry • 9% for municipal / residential services

  10. Threats to Water Quality and Supply in Canada • Contamination • Oil tanker accidents • Natural causes • Dumping of waste

  11. Threats to Water Quality and Supply in Canada • Contamination • Industrial • By-products of production in oil refineries, pulp mills, nuclear reactors, and chemical factories

  12. Threats to Water Quality and Supply in Canada • Contaminaton • Municipal Raw sewage, detergents, and solvents

  13. Threats to Water Quality and Supply in Canada • Misuse • 67% of accessible surface water is used by agriculture • When farmers till land, it loses moisture – so land is irrigated – watered by artificial means

  14. Solutions! • Current technology can = sustainable water management • Micro-dams • More efficient rainwater harvesting • Reclaimed/recycled water • De-salinated seawater • Low energy sprinkler systems • Drip irrigation directing water to roots • High efficiency/low flow toilets • Taxes or user rates to encourage water conservation

  15. Issue: Ozone Layer • In the last 30 years, the Ozone Layer has been getting thinner over the poles. • The hole in the ozone layer is caused by too many CFC’s – chlorofluorocarbons – in the atmosphere.

  16. 2010

  17. Change Is in the Air: The Ozone Layer • Ozone layer =thin layer 15-50 Km above surface of Earth • O3=only gas that can block UV rays from sun • UV rays can cause skin cancer • Damages plant and animal species (plankton) • Penetrates up to 20 m into ocean • Depletion most evident at N & S Poles, esp in Spring • 60% depleted above Antarctica • Why there? Higher levels of chlorine found there will react to destroy the Ozone!

  18. Chemicals, esp. Chlorofluorocarbons (CFCs) cause 80% of damage • Widely used since 1930s • Coolants for fridges & air conditioners • In foams, solvents & aerosol spray cans • UN Environmental Program (UNEP) working to phase out use of ozone depleting chemicals • Montreal Protocol (1987): all industrial nations agree to cut use of CFCs by 2000 • Amount of chemicals released increasing • Only complete elimination of CFCs & recapture of those in the atmosphere will halt damage to the Ozone Layer • Simple phasing out of CFCs = 100 yrs to reach 1980’s atmospheric condition http://www.unep.fr/ozonaction/information/video/ozzy.htm#english Ozone Depletion

  19. Gases trap heat energy from sun similar to a greenhouse • Natural factors (volcanoes, meteor impacts) have caused climate change in past • Since industrial Rev. burning fossil fuels (coal, oil, gas) = more CO2 in atmosphere • Causes rise in temperature 1-3 degrees by 2050 (slight changes=profound impact) Global Warming

  20. The Greenhouse Gas Effect • The greenhouse effect is a natural process by which some of the radiant heat from the Sun is captured in the lower atmosphere of the Earth, thus maintaining the temperature of the Earth's surface.

  21. The Greenhouse Gas Effect • The gases that help capture the heat, called “greenhouse gases,” include water vapor, carbon dioxide, methane, nitrous oxide, and a variety of manufactured chemicals.

  22. It starts with the Greenhouse effect

  23. Human Causes • KEY ACTIONS: • Cars (burning gas/oil) • Factory Emissions - this is a big one • Deforestation of “the lungs of the earth” The burning fossil fuels such as coal, gas and oil and clearing forests we have dramatically increased the amount of carbon dioxide in the Earth’s atmosphere and temperatures are rising.

  24. Physical Effects of Warming • Melting ice caps – which adds freshwater to ocean decreasing its salinity – affects ocean currents. • Melting permafrost – storage basin for massive amounts of CO2 – tipping point.

  25. Physical Effects of Warming • “Weird Weather” – increasing numbers of storms, floods, hurricanes, tornadoes. • Shifts in Climate Zones and Vegetation Patterns.

  26. Seeing the Changes • The number of Category 4 and 5 hurricanes has almost doubled in the last 30 years. • Malaria has spread to higher altitudes in places like the Colombian Andes, 7,000 feet above sea level.

  27. Seeing the Changes • The flow of ice from glaciers in Greenland has more than doubled over the past decade. • At least 279 species of plants and animals are already responding to global warming, moving closer to the poles.

  28. Catastrophic Consequences • Deaths from global warming will double in just 25 years -- to 300,000 people a year. • Global sea levels could rise by more than 20 feet with the loss of shelf ice in Greenland and Antarctica, devastating coastal areas worldwide.

  29. Catastrophic Consequences • Heat waves will be more frequent and more intense. • Droughts and wildfires will occur more often. • The Arctic Ocean could be ice free in summer by 2050. • More than a million species worldwide could be driven to extinction by 2050. • Displaced peoples – currently 25 million environmental refugees. • Destruction of property + infrastructure.

  30. Problems • Arctic sea ice shrinking & seasonal melt = weeks earlier than in past • Polar bears starving, need ice to hunt seals • Bears’ birth rate & av. Weight has fallen • Arctic communities face sinking shorelines as permafrost melts • Survival rate of BC’s spawning salmon 1/3rd what it was in 1990 • Warmer water temps deplete phytoplankton salmon eat, less growth, smaller fish can’t survive swim upstream • Ripple effect in ocean food chain if salmon stocks reduced • Winter recreation areas economically impacted by warmer winters • Freak weather systems & devastating storms more likely • More droughts and forest fires Benefits • Tree line could be extended further north and higher up mountains • Shorter growing seasons could benefit farmers • Possibly offset by droughts Canada

  31. What are some current agreements to stop Climate Change / Pollution?

  32. Climate Change Agreements • The Kyoto Protocol is an international agreement under the United Nations Framework Convention on Climate Change to cut greenhouse gas emissions that cause climate change.

  33. The Kyoto Protocol Solution • Kyoto Protocol • Plan to reduce greenhouse gas emissions by 6% of our 1990 levels by 2012 - Solutions include phasing out coal plants, expanding renewable energy sources and public transit, and creating new efficiency standards for vehicles and buildings. • Canada among top emitters of greenhouse gases, and despite Kyoto our levels are increasing

  34. USA withdrew from Kyoto in 2001

  35. Kyoto Targets • Canada initially signed on, but the US refused to a long-term commitment. • Canada recently pulled out of Kyoto (Dec. 2011) and now does not have a pollution reduction plan.

  36. Arguments against Kyoto • Concerned that meeting goals will involve high costs to businesses and government and possible loss of jobs • Provincial governments must regulate polluting industries despite the fact that the federal government signed the agreement without consulting the provinces • Some argue not enough evidence that global warming to blame for climate change

  37. Kyoto & Canada • 2006 - Canada's greenhouse gas emissions were up by 24% • far from the government's commitment to meet a target 6% below the 1990 levels

  38. Solutions! • Many sustainable sources of energy • Wind turbines, solar power, tidal power, ground source energy, geothermal power • Greenpeace believes wind power could provide 10% world’s electricity needs in next 20 years • New hydrogen or methanol fuel cells could be adapted for cars, buses, homes and industries

  39. Cause: Fossil fuel burning in addition to smelting of various ores releases sulphur dioxides, nitric oxides, nitrogen dioxides. Mostly industrial in origin. Effects: Global hydrological cycle becomes acidic. Plant and animals are stunted, killed, or deformed. Crops can fail, and the global amount of fresh water is diminished due to acidification. Human Health Effects: From increase in colds, flues, and respiratory infection, to increases in breast and colon cancer. Also, problems associated with loss of fresh water supply. Acid and toxins enter the human system through any food or drink related to water. Areas of Focus: While primarily focused on industrial areas, some areas have been ravaged by acid rain. The Great Lakes have lost much of their original life due to acid rain. The Eastern Seaboard of the United States, and many parts of Europe rate high. Animation: http://www.emu.dk/gsk/fag/fys/ckf/fase1/1fokv/syrer_og_baser/syreregn_animation.swf Acid Rain

  40. Which areas are affected by Acid Rain?

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