Childrens Illustrated Encyclopedia

childrens_illustrated_encyclopedia_template_US_layer_v1

418

Cleaning up

neutralizing chemicals can be used

to clean up pollution. Spilled

oil, for example, can be

countered with detergents.

But unfortunately these

chemicals can do just as

much damage as the

original spill.

Sometimes the only

way to clean up is to

physically remove

the pollutant. Sadly

the damage is often

already done,

although it may not

be very obvious.

rain foreStS

Since 1945, more than half of the world’s

rain forests have been destroyed. they are

cut down for timber or burned to clear space

for farmland. Burning produces carbon

dioxide, contributing to global warming.

Scientists are increasingly concerned about

the impact of this on the environment.

houSehold pollution

Some of the polluting gases that were

destroying the ozone layer came from

household devices. the most damaging

were chlorofluorocarbons (CfCs), used

as propellants in aerosol cans and inside

the cooling systems of refrigerators. today,

in the move to reduce pollution, less

harmful gases have replaced CfCs.

oil Barrier

Crude oil is a particularly

harmful chemical pollutant.

however, because oil floats

on water, an oil slick created

by a spillage from a wrecked

tanker can be contained by

barriers. the oil must then

be dispersed or collected

quickly because, if it is left,

it will eventually thicken and

sink. also, oil barriers cannot

withstand storms.

holeS in the ozone layer

in the late 1970s, scientists detected

“holes” in the ozone layer above

the South and north poles.

probably caused by air pollutants,

particularly CfCs and methane,

the “holes” seemed to be

growing larger. in 1987, more

than 30 countries signed an

agreement called the Montreal

protocol, which sharply reduced

CfC production worldwide.

Energy-saving lamps

reduce pollution, but just

switching off lights helps

even more.

An aerosol is a mixture of

product and propellant.

The dark patch is the

“hole” in the ozone layer

above the Antarctic.

The can is pressurized

by the propellant gas.

energy Saving

Much of the pollution that we produce is the result of

burning fossil fuels in power stations and motor

vehicles. generators and engines can be made

more efficient so that they use less fuel.

individuals, too, can save

energy and reduce

pollution by making use

of energy-efficient light

bulbs and other

appliances in the home,

and by using cars less.

Special V-shaped

paddles are used to

push the oil sludge

into heaps.

Where possible,

mechanical scoops

remove spilled oil sludge.

atmosphere

Climates

Conservation

and endangered species

energy

Find out more

pollution

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