environmental problems. kenyan proverb treat the earth well. it wasn’t given to you by our...
TRANSCRIPT
Environmental
problems
Kenyan proverb
Treat the Earth well. It wasn’t given to you by our
parents. It was loaned to you by our children.
http://www.youtube.com/watch?v=ZPSjjcPIAcQ&feature=watch_response
Watch the video about environmental problems
What have you done for our planet?
I’ve always / never………
I’d like other people to……
Discuss in pairs
Pollution
Waste
Deforestation
Endangered
species
Greenhouse effect
Acid rain
Global warming
http://www.youtube.com/watch?v=p1KxC-S7QgA
A video about pollution
Air pollutionWhat causes air pollution?• car exhausts
• emissions from industrial production (factories, power stations) - dust, smoke, smell…
Which gases in the air are poisonous?
• sulphur dioxide (SO2)
• nitrogen oxide (NO)
• carbon dioxide (CO2)
What does polluted air cause?
• health problems
• climate changes (changes in weather patterns – ice at the North and South Pole melt, sea level rises => flooding)
Water pollution
What causes water pollution?• industrial waste
• chemical fertilizers and
pesticides
• oil refineries
• accidents of huge cargo ships
• dumping toxic pollutants in the
water
Waste
• industrial waste
• domestic waste
• litters in the streets
RecyclingIf yes,
what?
Do you recycle?
If not, why?
Endangered animalsWhat animals are in danger?
Why are the
animals in danger?
What are they
hunted for?
• some of the animals have become very rare and are threatened by extinction (red lists)
• some animals are protected (bats, rhinoceros, the giant pandas,...), some are bred in captivity for releasing in the wild later, so they have the best chance of survival
• to save endangered animals, it’s necessary to protect their habitats (=special places where particular animals live) from destruction, they need to live in a balanced community (each
animal species is a member of a food chain, if one of them disappears, the system may collapse)
Deforestation
Why are the trees / rainforests cut down?
What does it cause?
• rainforests help to control global warming because they absorb carbon dioxide
• in recent years large areas of rainforests have been destroyed (trees have been cut down – land / wood is needed for farming, firewood, buildings, furniture => millions of animals and plants are killed too)
• rainforests grow on poor soils and when they are cut down or burned, the soil is washed away in the tropical rains, and these areas may turn to desert
Global warming – greenhouse effectExplain greenhouse effect
global warming is caused by greenhouse effect
• normally, heat from the sun warms the earth and escapes back into space
• several gases, so-called greenhouse gases (carbon dioxide – produced by burning fossil fuels, nitrogen oxides - from car exhausts, CFCs – chlorofluorocarbons from aerosol and refrigerators) go up into the atmosphere and with water vapour prevent heat from escaping
• because the heat can’t leave, the Earth gets warmer = global warming
Acid rainWhat is acid rain?
What does acid rain cause?
• the smoke which is produced by factories and cars is mixed with water vapour in the atmosphere
• they form sulphuric acid and nitric acid
• sunlight turns these acids into poisonous oxidants which fall in rain or snow onto tress and gradually kill them
• save energy, water• use alternative sources of energy• don’t use cars so much• recycle (saves energy and raw materials, reduces
damages of the countryside• sort out the waste (many cities have bottle banks
and can banks)• use new energy sources, alternative forms of
transport• buy green products (buy environmentally
friendly products which can be recycled)• use recyclable paper• use deodorant sprays without CFCs • protest against pollution, killing animals,…
Solution ?
Alternative sources of energy
• most of the energy we use today comes form coal, oil and gas, but these will not last forever
• burning them is slowly harming the atmosphere => need for new ways of supplying energy
What are alternative sources of energy?
Why do we need them?
SOLAR POWERusing the sun’s energy as heat or to make electricity
WIND POWER building modern windmills
WATER POWER- generating hydroelectric
power from river water in mountain areas
- electricity can be created from sea water flowing in and out with the tides
Environmental groups
What can happen?!