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Speech about enviroment ( air pollution )!

Autor: dusia141

I’ve prepared short speech about our environment. You probably know something about air pollution but I’m going to tell you something more.
We often hear phrase: ‘I’ll go out for a breath of fresh air’. But how many of us realize that this has become irrelevant in today’s world, because the quality of air in our cities is realy bad.
The moment you step out of the house and are on the road you can actually see the air getting polluted; a cloud of smoke from the exhaust of a bus, car, or a scooter; smoke billowing from a factory chimney, fly ash generated by thermal power plants, and speeding cars causing dust to rise from the roads. Natural phenomena such as the eruption of a volcano and even someone smoking a cigarette can also cause air pollution.
Air pollution is aggravated because of four developments: increasing traffic, growing cities, rapid economic development, and industrialization. The Industrial Revolution in Europe in the 19th century saw the beginning of air pollution as we know it today, which has gradually become a global problem.
Smog
The term smog was first used in 1905 by Dr H A Des Voeux to describe the conditions of fog that had soot or smoke in it. Smog is a combination of various gases with water vapour and dust. A large part of the gases that form smog is produced when fuels are burnt. Smog forms when heat and sunlight react with these gases. Smog can affect outlying suburbs and rural areas as well as big cities. Its occurrences are often linked to heavy traffic, high temperatures, and calm winds. During the winter, wind speeds are low and cause the smoke and fog to stagnate; hence pollution levels can increase near ground level. This keeps the pollution close to the ground, right where people are breathing. It hampers visibility and harms the environment. In fact, in the early part of the 20th century, heavy smog in some parts of Europe resulted in a decrease in the production of natural vitamin D leading to a rise in the cases of rickets. Smog causes a misty haze similar to fog, but very different in composition. In fact the word smog has been coined from a combination of the words fog and smoke. Smog refers to hazy air that causes difficult breathing conditions.
Acid rain
Another effect of air pollution is acid rain. The phenomenon occurs when sulphur dioxide and nitrogen oxides from the burning of fuels combine with water vapour in the atmosphere and fall as rain or snow. These gases can also be emitted from natural sources like volcanoes. Acid rain causes extensive damage to water, forest, soil resources and even human health. Many lakes and streams have been contaminated and this has led to the disappearance of some species of fish and it also has extensive damage to forests and other forms of life. It can corrode buildings and be hazardous to human health. Because the contaminants are carried long distances, the sources of acid rain are difficult to pinpoint and hence difficult to control.

Fly ash
With the boom in population and industrial growth, the need for power has increased manifold. Nearly 73% of world’s population installed power generation, of which 90% is coal-based generation with diesel, wind, gas, and steam making up the rest. Thermal power generation through coal combustion produces ash that causes serious environmental problems.
Commonly known as fly ash, these ash particles consist of silica, alumina, oxides of iron, calcium, and magnesium and toxic heavy metals like lead, arsenic, cobalt, and copper.
THE END
In many countries in the world, steps are being taken to stop the damage to our environment from air pollution. Scientific groups study the damaging effects on plant, animal and human life. Legislative bodies write laws to control emissions. Educators in schools and universities teach students, beginning at very young ages, about the effects of air pollution . But it does’ t help. In the world there are still lots of people who don’t care about our environment. We should encourage them to protect it. The world is our home so we should take care of it.
We should encourage our family not to use car so often, whenever possible take their bicycle or use public transport.
we also should reduce the use of aerosols in the household. and switch-off all the lights and fans when not required.
It isn’t hard to do. If everyone do it, our environment will become more clear.

Thanks.

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