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POLLUTION OF THE ENVIRONMENT
The Greenhouse Effect
People often think that the greenhouse effect and destruction of
the ozone layer are the same thing. They are not. Some of the same
chemicals cause both the problems, but they are not related in any
other way.
The earth is surrounded by the atmosphere. This is made from different
types of gas including oxygen, nitrogen and carbon dioxide.
The atmosphere acts like a blanket around the earth, keeping it
warm. It lets heat from the sun in and keeps some of it in. Most
heat from the sun reflects or bounces off the sea and goes back
out into space.
Gases like carbon dioxide make up this blanket and are called greenhouse
gases. The problem is that due to human activity like burning coal,
oil and natural gas creates more and more carbon dioxide. This all
means that the gas blanket is getting thicker and we all know what
happens when you use a thicker blanket, you get hotter. Another
way of thinking about it is that the greenhouse gases act like the
glass in a greenhouse. They let the heat in, but don’t let
it out. This is why it is called the greenhouse effect.
So what’s the problem? An increase in temperature of just
1.5°C could cause massive changes. If the ice at the South Pole
melts and flows into the sea, the level of the sea will rise. This
will cause flooding in low level parts of the world near the coast,
including Belfast and Dublin.
If the weather changes in the countries that grow our food, we
may have food shortages.
Acid Rain
Acid rain is caused by us burning lots of fossil fuels like coal.
The gases in the smoke rise into the sky and mix with the clouds.
In the clouds the pollution causes the water to become slightly
acidic.
The acid rain will not burn your skin as the acid is not that strong.
However, it is strong enough to damage the leaves of trees. It weakens
the leaves so diseases can get in easily and make the tree sick.
If the soil becomes too acid plants cannot grow, so there is no
food for animals. Acid water in rivers and lakes can release poisonous
chemicals from the soil and rocks and so kill water life.Acid rain
also damages stone buildings, wearing away blocks and carvings.
Destruction of the Ozone Layer
The ozone layer is a layer of gas, called ozone, high up in the
atmosphere. It acts like a giant sunscreen, stopping harmful types
of sunlight reaching the surface. This harmful light causes sunburn
and skin cancer.
The ozone layer stop almost all the harmful light getting through.
A little bit has always reached the surface and that is why we have
always got sunburnt.
The problem is that gases called C.F.C.s, which is short for Chlorofluorocarbons,
destroy the gas ozone and allow more of the harmful light to get
through.
C.F.C.s come from fridges and freezers. When they are thrown away
the gas leaks out and rises into the sky where it attacks the ozone
layer. In the past C.F.C.s came from spray cans like hairspray,
but they are not allowed to be used in them anymore.
To stop destruction of the ozone layer we need to remove the gas
from fridges and freezers before they go to landfill. To protect
yourself from the harmful sunlight, always use sun cream in the
summertime to avoid getting sunburnt.
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