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PERSONAL RESPONSES YOUNG LOVE I think that young love, even if very important
Verbo potere Si può tradurre con i verbi "can" - "could", "may" - "might".
AQUAE SULIS Although still mostly buried under magnificent Georgian streets,
When people think about air pollution, they usually think about smog, acid rain, CFC's, and other forms of outdoor air pollution. But air pollution can also exist inside homes and other buildings.
Every year, for these problems, the health of many people is affected by chemical substances present in the air and inside buildings.
Air is the ocean we breathe. Air supplies us with oxygen which is essential for our bodies to live. Air is 99% nitrogen, oxygen, water vapour. But human activities can release substances into the air, some of which can cause problems for humans, plants, and animals.
There are many types of pollution, as smog, acid rain, the greenhouse effect, and 'holes' in the ozone layer. Each of these problems has serious implications for our health and for the environment.
One type of air pollution is the release of particles into the air from burning fuel for energy. The particles are very small pieces of matter. This type of pollution is sometimes referred to as 'black carbon' pollution. The exhaust from burning fuels in automobiles, homes, and industries is a main source of pollution in the air. Some authorities believe that also the burning of wood and coal in fireplaces and barbeques can release significant quantities of damaging particles into the air.
Another type of pollution is the release of gases like carbon monoxide, nitrogen oxides, and chemical vapours. These can take part in chemical reactions once they are in the atmosphere, forming smog and acid rain.
Pollution also needs to be considered inside our homes, offices, and schools. Some of these pollutants can be created by indoor activities such as smoking and cooking. We spend about 80-90% of our time inside buildings, and so our contact to damaging indoor pollutants can be serious.
Let's examine some type of air pollution in detail:
Smog is a type of large-scale outdoor pollution. It is caused by chemical reactions between particles derived from different sources, like car exhaust and industrial emissions. Cities are often centres of these types of activities, and many suffer from the effects of smog, especially during the warm months of the year.
For the cities, the causes of pollution may be different. Depending on the geographical location, temperature, wind and weather factors, pollution is dispersed differently.
When air close to the earth is cooler than the air above it, the pollution disperses, it goes above. In summer is too simply to create smog and too hardly to dissipate it.
Another consequence of outdoor air pollution is acid rain. When a pollutant, such as sulphuric acid react with drops of water in the air, the water (or snow) can become acidified . The effects of acid rain on the environment can be very serious. It damages plants, it poisons the soil, and it changes the chemistry of lakes and rivers. Acid rain can kill trees and harms animals, fish, and other wildlife.
The Greenhouse Effect referred to as global warming, and it researcher think that it comes from the build up of carbon dioxide gas in the atmosphere. Carbon dioxide is produced when fuels are burned. Plants convert carbon dioxide back to oxygen, but the release of carbon dioxide from human activities is higher than the world's plants can convert. The situation is made worse since many of the earth's forests are being removed, and plant life is being damaged by acid rain. For these reason, the carbon dioxide in the air is continuing to increase. The climate is going to become more and more warm and the polar ice caps may melt.
Ozone reduction (ozone holes) is another consequence of pollution. Particles released by our activities affect the stratosphere and one of the atmospheric layers surrounding earth. The ozone layer in the stratosphere protects the earth from damaging ultraviolet radiation from the sun. Release of chlorofluorocarbons (CFC's) from spray cans, cooling systems and refrigerator removes some of the ozone, causing 'holes', so the earth receives the dangerous radiation. Ultraviolet radiation is known to cause skin cancer and has damaging effects on plants and wildlife.
Air pollution can affect our health in many ways with both short-term and long-term effects.
Some individuals are more sensitive to pollution than others. Young children and elderly people often suffer more from the effects of air pollution. People with health problems may also suffer more when the air is polluted.
Examples of short-term effects include irritation to the eyes, nose and throat, allergic reactions and respiratory infections such as bronchitis and pneumonia.
Long-term health effects can include chronic respiratory disease, cancer, heart disease.
Continual exposure to
air pollution affects the lungs of children and may aggravate or complicate
medical conditions in the elderly. It is estimated that half a million people
die prematurely every year in the