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The Environment
Environmental challenges facing Canadians
• assess environmental challenges facing Canadians, including
− global warming − ozone layer depletion − fresh water quality and supply• Pages 420-433 of Counterpoints
Today’s Objectives
• How does industrial and technological development affect the environment (e.g., global warming)?
• What are some possible responses to global warming (e.g., Kyoto protocol)?
Global Warming
After watching An Inconvenient Truth, do you remember what gas contributes the most to global warming? CO2!
What is global warming? The overall warming trend of our
atmosphere What is the greenhouse effect?
Gases in our atmosphere trap the heat energy from the sun, causing our atmosphere to warm up
Things are warming up…
Natural Factors: Volcanic Eruptions Meteor Impacts
Human Factors: Since the Industrial Revolution,
humans have been the largest contributor to global warming Burning of fossil fuels (coal, oil,
natural gas) emits CO2 What are some things we use
fossil fuels for? Deforestation (trees convert
CO2 into O2) Agriculture contributes to
methane (CH4) emissions
What causes global warming?
The emission of all these gases traps heat energy from the sun in our atmosphere
What effect does this have on our environment? Rising global temperatures (Fig. 17-15, pg. 432) Rising incidence of violent storms Extended range of tropical diseases Rising sea levels caused by melting ice caps Destruction of aquatic and terrestrial habitats
The Greenhouse Effect
Greenhouse Gases contributing to Global Warming
Arctic regions: ice sheets shrinking, loss of habitat
British Columbia: warmer water in the Ocean is killing Salmon food supply, reducing the number of Salmon Salmon are a keystone
species Winter recreation: less
snow means less skiing! Increasing droughts:
can destroy agriculture, lead to more forest fires
The effect on Canada?
1997: Kyoto Protocol An agreement among countries promising to reduce
greenhouse gas emissions by 6% of our 1990 level by 2012
Countries not meeting their target can buy credits from other countries below their allotted levels
Fossil fuel industry against Kyoto, claim impossible standards, potential loss of jobs
Sustainable energy sources Can be used to lessen dependence on fossil fuels
Wind turbines, solar panels, tidal power, geothermal power
Wind power alone could account for 10% of the world`s electricity demands
Hybrid cars, hydrogen or methanol fuelled power cells
Possible solutions?
Sustainable Energy
Tidal Power
Geothermal Power
Kyoto Protocol
Green: ratified agreement, Grey: Undecided, Brown: will not ratify
1) China1 – 17%, 5.8 2) United States3 – 16%, 24.1 3) European Union-273 – 11%, 10.6 4) Indonesia2 - 6%, 12.9 5) India – 5%, 2.1 6) Russia3 – 5%, 14.9 7) Brazil – 4%, 10.0 8) Japan3 – 3%, 10.6 9) Canada3 – 2%, 23.2 10) Mexico – 2%, 6.4
World Contributors of GHG emissions
(2005 Rank, Country, % of world GHG emissions, tons GHG per capita)
• How does industrial and technological development affect the environment (e.g., ozone layer depletion)?
• What are some possible responses to ozone layer depletion (e.g., Kyoto protocol)?
Ozone layer depletion
The ozone layer is a thin layer of ozone (O3), 15-50 km`s above the surface of the earth (Fig. 17-11, pg. 430) Ozone is the only gas in the
atmosphere that can block Ultraviolet (UV) radiation from the sun
UV radiation can cause skin cancer, damage plants and animals, and destroy habitats such as coral reefs
1980s: discovery that ozone layer was thinning Holes developed at the poles, up to
60% disappeared over Antarctica
Change is in the Air
Chlorofluorocarbons (CFCs) have done 80% of the damage (CFC emissions chart, Figure 17-12, pg. 430) CFCs used for cooling refrigerators and air
conditioners as well as in aerosol spray cans United Nations Environmental Program (UNEP)
began phasing out the use of CFCs in 1987 All industrialized (developed) nations cut their use
CFCs; called the Montreal Protocol Developing countries would phase out CFCs by
2000 Even after being phased out, could take a century
for the ozone layer to return to pre 1980s levels
Causes? Solutions?
With a partner, answer the Activity questions on pg. 433 (1-5)
Assignment
• What are some threats to water quality and supply in Canada and the world? (e.g., contamination, misuse) and what are some possible solutions (e.g., treatment technologies, conservation)
Fresh water quality and supply
People simply cannot survive without clean drinking water Each person requires AT LEAST 5
litres of fresh water every day for good health (how much do you drink?)
Water is also needed for many other uses: Agriculture, industry, bathing,
washing, etc.
Yet, humans, particularly in the developed world, waste or pollute massive amounts of water everyday
Water: The Indispensable Resource
World Fresh Water Storage: 3% of the water on Earth is fresh
water Nearly 78% of that is frozen in
glaciers and ice caps Most of the remaining fresh water is
underground, called groundwater Water deficits:
A measure of how much more groundwater is being used than is being returned into the ground (Fig. 17-4, pg. 423)
What does this mean for the future? What are the main threats to
global water supply? Increased population, pollution
Threats to groundwater supply
Increasing population strains the water supply Falling water tables and diversion of surface
water lead to shortages of fresh water Many large rivers are almost dry by the time the
reach the sea due to human demand (Nile, Ganges, Yellow) Threatens agriculture 40% of worlds harvest comes from irrigated* cropland USA, China, India facing water shortages and they
produce half the worlds food
Threats to groundwater supply
Farmer are able to pump groundwater from aquifers (underground layer of rock that water can pass through) using wells
Water is being pumped out of aquifers much faster than it is replenished from rain
When this occurs, the water table lowers, and wells run dry (Fig. 17-5, pg. 425)
*In northern China, water table drops 1.5 meters each year!
How do we get groundwater?
Surface water: lakes, rivers, coastal waters Has been used for disposal of sewage,
agricultural and industrial waste (chemicals, pesticides, oil, etc.)
This damages water quality, and animal habitat
Some lakes and rivers are so badly polluted, can no longer support life and certainly cannot be used for drinking water!
Threats to surface water supply and quality
Education: conservation of our water is very important…do not waste it!
New technologies: Rainwater harvesting Reclaimed or recycled water for
agriculture Desalinated seawater Low flow sprinklers, toilets,
showers Low flow toilets can reduce by
70% the amount of water needed to flush!
Drip irrigation (reduced evaporation)
Taxation on groundwater use
Solutions
With a partner, answer the activity questions on page 430 (1,2,4,5)
Of the environmental problems we talked about in this chapter, which one do you consider most likely to affect your lifestyle if it is not addressed? Explain your answer
Assignment