Global warming and the Greenhouse Effect

Scientists say the temperature of the earth could rise by 3^o C over the next 50 years. This may cause drought in some parts of the world, and floods in others, as ice at the North and South Poles begins to melt and sea levels rise.

Global warming is caused by the greenhouse effect Normally, heat from the sun warms the earth and then escapes back into space. But carbon dioxide and other gases in the atmosphere trap the sun's heat, and this is slowly making the earth warmer.

A greenhouse becomes hot for the same reason. Its glass lets the sun's heat pass through, then stops some of it from leaving. That's why scientists call the problem of Earth's rising temperature “The Greenhouse Effect”.

Pollution sends 4 main 'greenhouse gases' into the atmosphere. These are:

1) Carbon dioxide (CO2)

2) CFCs (Chloro-fluoro-carbons)

3) Methane

4) Nitrous Oxide

CO₂ - The most important greenhouse gas, CO₂, causes half of the problem. Nearly 6 billion tonnes of it enters the atmosphere every year. How? From the burning of fossil fuels (coal, gas and oil). An extra 1.5 billion tonnes every year comes from the burning of rainforest trees. This makes the problem worse in another way, too. Normally, trees absorb CO₂. Today there are fewer and fewer trees. That means more and more CO₂. In fact 50% of all carbon burned since 1850 is still in the atmosphere. CFCs -These gases are in...

...Aerosols (Britain alone used 800 million aerosols in 1988).

...Refrigerators (the CFCs are in the liquids which keep fridges cold).

...Plastic boxes (for hamburgers, pizzas, etc).

CFC molecules are very dangerous. Each one can trap 10.000 times more heat than a molecule of CO₂. And they don't just stay in the air - they destroy it. Because of CFCs the top level of the atmosphere (the ozone) is now getting thinner.

Methane and Nitrous Oxide - these gases come from...

... fertilizers

... cows stomachs

... rubbish

Most scientists agree that the Greenhouse Effect will add between 1.9°-4° to the Earth's temperature by 2030 (It's already 1/2⁰ hotter than in 1900).This will change the weather everywhere. For example, the ice at the North and South Poles will start to melt. And when that happens the level of the sea will rise. If it rises one metre by 2030 there will be serious floods in many countries. Eighteen million people wilt lose their homes in Bangladesh and 8 million in Egypt. A rise in sea level will have other effects, too. Holland, for example, already spends more on sea­walls (as a %) than America spends on military defence. Experts think that in 50 years, the Greenhouse Effect will cost 3% of every country's money each year. Then there's the problem of food. When the climate changes there will be less food in the world. At the moment, areas like the mid-west of America and central Russia grow a lot of wheat. In the future that may change when the USA and the countries of the CIS become too dry for farming. Other countries (like Canada and Sweden) will become wetter, but that won't help. The soil there isn't as rich. It won't be possible to grow the same amount of food as before.

 

1) What may global warming result in?

2) Why is the problem of Earth’s rising temperature called “The Greenhouse effect”?

3) Why is it happening?

4) Where do 4 main “greenhouse gases” come from?

5) What will it do?

 

2. Read the text and put in the given words:

Poor, species, absorb, desert, cut down, extinct, soil,areas

 

DEFORESTATION

 

Rainforests help to control global warming because they … carbon dioxide. In recent years, large …….. have been destroyed, as the trees are …… for wood or burned to clear the land for farming. The burning releases large amounts of carbon dioxide into the atmosphere.

Many rainforests grow on ….. soils and when they are cut down or burned, the … is washed away in the tropical rains, so that the area may turn to …. Many plant and animal … that live there could become ….

 

3. Read the text and do the exercises given below.

 

 

THE ANIMALS WE MIGHT LOSE FOREVER

 

1. Disaster did not strike the tiger until a post-war demand for hardwood triggered a massive onslaught on tropical forests. Vast areas, which had stood for
60 million years, disappeared at the rate of 50 acres a minute. Deprived of shelter and prey, the tiger was doomed. In 1972, its population had dropped from 40,000 to less than 2,000 in 40 years. It's now doubled on WWF reserves.

2. The blue whale, the largest animal ever to have lived on earth - reaching lengths of 100 feet and weighing up to 150 tons. The whale was exploited as a source of meat, fats and oils. Its food-sieving plates (baleen) were used to make whalebone corsets. Despite repeated warnings from scientists, whalers continued to slaughter blue whales until their number was one thirtieth of its original
level.

3. Wild black rhinos have become the ultimate symbol of threatened African wildlife. Thirty years ago there were more than 100,000 of them. Today they have dwindled to fewer than 4,000. In Kenya, Zambia and Zimbabwe, poaching rhino horn is still the way to a fortune.

4. There used to be 300 species of elephant - today there are just the African and Indian. In Africa, where an estimated 75,000 still survive, 10,000 a year are shot by poachers for their tusks. The trade has a street value of $1 billion. Herds return to the best places to find crops and gardens and are killed by farmers.

5. Emblem of the World Wildlife Fund, the giant panda faced extinction by the end of the century until, ironically, man stepped in. For it was man's
destruction of the forest which had left the pandas in small, isolated pockets. Leopards occasionally kill the younger ones, and pandas can be accidentally
snared in the traps set to snare musk deer. Occasionally giant pandas are shot: their skins are prized as trophies, or used as rugs and wall hangings.

 

 

1) Find out the following information as quickly as you can:

a) What first started the disappearance of tigers, and why?

b) What is the largest animal in the world?

c) Why was the blue whale hunted?

d) What is the reason for poaching rhino horn?

e) What parts of elephants does ivory come from?

f) How many species of elephant did there use to be?

g) Why are giant pandas shot?

h) What causes the giant panda extinction?

 

2) Complete the gaps in this word puzzle with words from the text which match the definitions given (the paragraph number is given). If you complete it correctly you will make a word connected to the topic to fit in the box (it begins with e).

 

a) used(unfairly) for profit (para 2)

b) caught in a trap (para 5)

c) very big (para 1)

d) a group of animals of the same kind that can breed together (para 4)

e) in danger (para 3)

f) plants produced by farmers (para 4)

g) less in quantity (para 3)

h) sure to die (para 1)

i) an animal that is hunted and eaten by other animals (para I)

j) fierce attack (para 1)

k) state of being no longer in existence (para 5)

l) buying and selling of goods (para 4)

m) killing on a big scale (para 2).

 

 

a)

e

x

p

l

o

i

t

e

d

b)

s

c)

s

d)

e

e)

t

f)

r

g)

d

h)

d

i)

y

j)

a

k)

i

l)

d

m)

t

 

4. Look through the information and discuss the role of the ozone layer and the problem it faces.

 

THE OZONE LAYER

 

The ozone layer is a layer of gas high above the surface of the earth that helps to protect it from the sun's ultraviolet radiation, which can damage our skins and cause cancer. Scientists have recently discovered holes in the ozone layer, caused by substances called CFCs (chlorofluorocarbons).

CFCs are used in refrigerators, aerosol cans and in the manufacture of some plastic products. Some companies now make aerosols that do not contain CFCs, and these are often marked 'ozone-friendly'.

 

5. Think over the environmental effect after the Chernobyl explosion. Then read the text and express your opinion on the facts given in it.

 

CHERNOBYL CATASTROPHE

 

The whole world is aware of the tragedy happened in Ukraine on the 26^th of April 1986.

As the result of the explosion of the failed reactor a huge amount of radioactive substances was released into the atmosphere. Later on they left the large fall-out “spots” on the ground surface.

The radiation situation was determined by radionuclides with the period of half-decay from 8 days till 24390 years.

After the Chernobyl accident Belarus has become the zone of the ecological disaster. The situation got worse because radioactive contamination coincided with the formerly existing zones of high chemical pollution. 260,000 hectares of agricultural lands are forbidden to use for farming purposes. Thousands of hectares of forests are contaminated with radioactive elements. The Chernobyl catastrophe has affected the destinies of millions of people. The radioactive contamination of the ecosystems has created the conditions for making it impossible to conduct the agricultural production and manage forestry in the normal way for many decades.

In order to decrease the influence of radiation on the people considerable work was done during the post-accident period. Measures were taken to evacuate the people from the most dangerous districts, to provide for their medical check-up and treatment. Various measures were almost carried out – radioactive decontamination, agricultural treatment of soil, provision of clean food. However, these measurements are not enough yet. And international co-operation in this field serves the interests of the entire mankind.

 

The Green Answers

 

Work in groups. Discuss the following ways of solving ecological problems.

ALTERNATIVE ENERGY

 

Most of the energy we use today comes from coal, oil and gas. But these will
not last forever, and burning them is slowly harming the atmosphere. We need to
look for other ways of supplying energy:

 

a) Solar Power

 

1. We can use it directly.

Many modern buildings have big windows which face south. These collect solar power directly. In fact some buildings in North America and Scandinavia get 100% of their energy from the sun.

2. We can collect it on Earth.

Another way to collect the sun's power is with solar panels. These absorb and store energy on sunny days. But there are two problems with solar panels on Earth. They're expensive. They don't work very well on cloudy days.

3. We can collect it in space.

One answer to the problems of clouds is to collect solar power in space. The idea is expensive, but simple. Satellites with huge solar panels collect the sun's energy. Then they send it back to Earth. A series of satellites like this will be able to work for 24 hours a day.

 

b) Wave Power

 

25% of the world's electricity already comes from dams and rivers. Now, scientists are learning how to use the sea's power, too. What they're doing is collecting the energy contained in waves. At the moment wave machines are small and expensive They don't produce much electricity, either. But in the future they will be bigger and cheaper. One day scientists think they will produce between 25% and 30% of our electricity.

 

c) Wind Power

 

Several 'wind farms' already exist in Britain and other European countries. Each farm is a group of machines which turn wind power into electricity.

The problem at the moment is money. It's very expensive to develop and build wind farms. That's because they have to be in high places near the coast or on islands. This makes their electricity expensive, too. But in the future, electricity from fossil fuels and nuclear power will begin to cost more and more. Perhaps then wind farms won't look so expensive after all.

So, will energy from the sun, the wind, the sea, under the ground take the place of fossil fuels and nuclear energy completely? The answer is probably no, but natural energy will become more and more important. That's because:

- It will become cheaper

- It will be better for the environment

- It will make it possible to conserve fossil fuels

- It will be safer than nuclear power.

 

d) Geo-Thermal Power

 

As well as solar, wind and wave power, there are other kinds of natural energy, too. One is from the hot rocks and water at the centre of the Earth. This kind of 'geo-thermal' energy already heats thousands of buildings in Iceland, Hungary, Japan and New Zealand. (In fact, 60% of Iceland's energy comes from under the ground.)

 

2. RECYCLING

 

Recycling is the processing of used objects and materials so that they can be used again. About 50% of rubbish from homes and factories contain materials that could be recycled. Recycling saves energy and raw materials, and also reduces damage to the countryside.

Glass paper and aluminium cans can all be recycled very easily. Many towns have bottle banks and can banks where people can leave their empty bottles and cans for recycling. A lot of paper bags, writing paper and greetings cards are now produced using recycled paper.

 

Recycling … saves trees.

… saves energy.

… saves money.

… cuts pollution.

3. WE CAN'T STOP THE GREENHOUSE EFFECT, BUT WE CAN SLOW IT DOWN

 

There are several ways to do this:

1. Conserve Fossil Fuels - Some countries have already begun. Each person in Japan, for example, uses only 50% as much coal, gas and oil as the average American.

2. Conserve Rainforests - The Earth needs more trees, not fewer. South American, Asian and African countries must protect their rainforests, not cut them down.

3. Use Natural Energy - 20% of the world's energy already comes from the sun, sea and wind. To slow down the Greenhouse Effect, that number must rise to 50% in the next 20 years.

4. Ban CFCs - This is beginning to happen. Many companies have already banned CFCs.

 

Post-reading

Pair-work

Look through the entire information in Unit 6. According to these facts complete the dialogue.

 

· What do you think of the ecological situation in your place?

Ø …

· And what does the greatest harm to …

Ø … Do you agree with me here?

· … But I am not so pessimistic as you are.

Ø … You just don’t think much of this problem.

· That’s true.