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We breathe air from the time we are born
until the time we die.
Breathing fresh air is something nobody
should worry about. But certain human
activities have led to rapid deterioration of air quality. The moment you
are
on a road you can actually see the polluted air; a cloud of
smoke from the exhaust of a bus, or scooter; smoke
billowing from a factory chimney, flyash
generated by thermal power plants and construction sites send dust
floating in air.
Air is a fascinating mix
of gases, vapors, and different kinds of minute particles. The
things that are a cause for concern in air are:
Particulate:
They are bits of dust and soot floating in the air. They are sent up into air by almost anything that burns.
They prevent us from seeing as far as we could on a clear
day. They also block sun rays so that the earth can’t warm up
enough to help plants grow. They stick to leaves and do not
allow them to breathe. In humans they cause soar throat
and lung damage.
Carbon monoxide: One of the nastiest gases released when
combustion is incomplete, they sneak out from vehicles and also
from burning kerosene, coal or wood stoves . It can cause
headaches or make people feel tired and at higher concentration
even death.
Sulphur dioxide: A gas thrown into air when power plants and
factories burn coal and fuel. It has the capacity to travel hundreds
of kilometers. It is the main cause of people
having breathing troubles. They hurt plants and animals too.
They cause bigger trouble when they mix up with water to form acid
rain.
Nitrogen oxides: Tricky bunch of gases, they cause irritation to eyes and lungs.
SO2 and Nox change upon exposure to
sunlight convert to sulphuric and nitric acids. And when they
are formed up in the atmosphere they make the rain acidic. This
can cause severe
damage to the land, trees and buildings and even us.
Lead : Real trouble for people who
breathe too much of these. Specially, bad for kids as may affect
their brain. Most cars and scooters use leaded petrol to run,
and when this petrol is burned, lead goes sailing out into the
air. Today a few cities in the country have introduced unleaded petrol, but
many cities still plenty of leaded petrol is used.
Ozone : Nitrogen oxide, sunshine and few other chemicals are
required to make atmospheric ozone. Where there is ozone there
is smog ,dirty air that isn't too good for everyone. Too much
ozone harms not just people. Trees grow more slowly, they do not
make as many seeds or fruits. Animals also have trouble in
breathing in smoggy air.
But Ozone does a great job when it is
up about 25Kms above the earth, as it soaks up the ultra violet
rays from the sun before they hit the people on the earth, but
recently there aren't many of them up there resulting in a hole
in the sky which can cause skin cancers.
This is because people
have started using chemicals called chloro-fluoro-carbons
(CFCs) and halons. CFCs are used to make cups, plates
and other containers that are made of plastic like material
called styrofoam. They are also used to make the coolants that
are in refrigerators and air conditioners, as well as in some
computer parts. But CFCs don't stay long in those products. They
slowly leak out as they break apart, lots of CFCs also leak out
into the air as they are being used in various industrial
applications. Once they get out into the air they slowly drift
higher and higher to the Stratosphere. Once here the chlorine
atom from a CFCs molecule attacks and breaks ozone molecule to
form chlorine monoxide and oxygen. Since chlorine monoxide is
unstable, chlorine atom detaches from it soon and attacks
another ozone molecule. This way a chlorine atom can destroy
upto 1,00,000 ozone molecules!! Thus ozone layer is damaged resulting
in more harmful ultra violet rays reaching the
earth. This can cause cataract to skin cancer to less food
production.
Longer and Hotter Summers : Climate
Change
Your grandparents
must have told you that one did not require fans in the good old
times. Well imagine
spending an Indian summer ( which now stretches beyond 8 months)
without a fan now !! Impossible, right. Reasons, air pollution,
less greenery... Polluted air not only causes temperature
increase for a local area ( a green park is cooler than a
road) but also global warming. Weather records of last century
show that the average annual temperature of earth has
risen by half a degree during the last 100 years.
Increasing levels of carbon dioxide and other gases in the
atmosphere are leading to rise in temperature. These gases act
as a blanket and don't allow heat to escape from the
earth. Global warming can melt polar ice caps and drown islands
nations like Maldives, and cause severe droughts in some and
floods in other places.
Thus air pollution has both immediate and far reaching
consequences and each one of us should strive to make the air
cleaner.
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