The
Sun and UV Radiation
All of you know the sun, the great ball of light in the sky, the source of
energy on Earth. But did you know that some of the sun’s rays can be
very harmful to us. These rays, called Ultra-Violet (UV) rays, are very harmful
to life on our planet.
Harmful Effects of UV Radiation
Exposure to UV radiation causes the following health problems:
-
Skin
diseases
such as cancer
-
Eye
diseases
such as cataract
-
Suppression
of the immune
system, which
means you
can get sick
easily
The
Ozone Layer
High up in the sky, in the stratosphere, lies the ozone layer. It is an atmospheric
layer made up of ozone, which is a gaseous molecule containing three oxygen
molecules. It acts like a protective umbrella, preventing much of the harmful
UV radiation from reaching the Earth. The ozone layer is important because
it helps to protect life.
Ozone Depletion
In the 1980s, scientists discovered that the ozone layer was becoming thin,
allowing more UV radiation to reach the Earth's surface. Research showed
that chlorofluorocarbons or CFCs (used to keep things cold, make foam, and
soap and aerosols) are responsible for ozone depletion. There are other Ozone
Depleting Substances (ODS) such as methyl bromide (a pesticide), halons (used
in fire extinguishers) and methyl chloroform.
When CFCs reach the stratosphere, they break down and release the chlorine
atom. This chlorine atom reacts with the ozone to form oxygen and chlorine
monoxide (ClO) a reactive gas, which devours the ozone molecules. Imagine,
one chlorine atom can destroy 100,000 ozone molecules! When this happens
over a period of time, the ozone layer gets depleted.
What Is Being Done?
Many countries across the world got together and signed a treaty called the
Montreal Protocol in 1987 to ensure that people stop producing and using
ozone depleting substances.
What Can You Do?
You can do a lot to save the ozone layer. Here are some of the things that
you can do right away:
-
Spread
the message
about the importance
of the ozone
layer. You
can make posters,
write articles,
or just tell
your friends
and family.
-
Tell
people about
the harmful
effects of
UV radiation
and how to
protect themselves.
-
Encourage
people to buy
CFC-free and
ozone-friendly
products, especially
CFC-free refrigerators
and air-conditioners.
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Watch
Ozzy Ozone, the defender
of planet earth
In this video, Ozzy
Ozone and Alberta the
Albatross take a voyage
of discovery to find
out exactly who and
what is attacking the
ozone layer and how
children can play an
important role in making
a difference.This
video was developed
as part of UNEP's Work
Programme under the
Multilateral Fund for
Implementation of the
Montreal Protocol.
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