(共19张PPT)
Unit 4 Global Warming
What consumes energy?
electrical appliances
Where does come from?
energy sources
energy
Can you name any energy sources?
wind power energy
Wind energy is used to produce electricity by windmills.
nuclear energy
Dams are used to keep back ______ and raise its level for irrigation or for producing _________ by its falling water.
water
water power energy
electricity
solar power energy
Solar panels on the roof of a house are used to collect / trap solar energy, making your house warm or heating your water.
a coal power station
coal
fossil fuel
Do you know any other fossil fuel?
oil/petrol
fossil fuels
natural gas
mainly made up of methane
renewable or non-renewable?
Never run out.
Will run out.
coal, oil
natural gas
wind (wind power)
sun (solar energy)
uranium (nuclear energy)
water (hydro-electric power)
plant waste (biomass energy)
the sea (tidal energy)
N
N
R
R
N
R
R
R
Sources of energy Renewable/non-renewable
When fossil fuels are burnt,
what byproducts may be produced?
carbon dioxide
methane
water vapour
greenhouse gases
greenhouse
What is the greenhouse
made of and used for?
A greenhouse is made of glass and is used for growing plants, especially during cold weather.
Guess:
They trap heat from the sun and therefore warm the earth.
greenhouse effect
What do
greenhouse gases do?
温室效应
before
Lanina, a small town in Argentina, used to attract huge numbers of tourists every year. The weather there used to be mild with warm winter and cool summer. It was many series of animals and plants that impressed travellers deeply. It is no wonder that tourists considered it as the heaven in the world and everything there seemed to be in a perfect condition. However, a disaster was on the way. It was not until several years ago that local people realized it. Floods and sandstorms continued attacking the town, leading to the spread of diseases and the destruction of species. As a result, people there had to move out of the town.
climate, quanty, state, result in, consequence, range, compare…to, catastrophe, keep on, There is no doubt,
quantities
climate
ranges
There is no doubt that
compared
to
catastrophe
kept on
resulting in
consequence
state
1. SWSJ(P55-60).
2. Preview the article after class.
Homework