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| Sunday, 23 October 2005 |
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Junior Observer |  |
| News Business Features Editorial
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Acid in the rain
"Acid rain" is a broad term used to describe several ways that acids fall out of the atmosphere. A more precise term is acid deposition, which has two parts: wet and dry. Wet deposition refers to acidic rain, fog, and snow. As this acidic water flows over and through the ground, it affects a variety of plants and animals. The strength of the effects depend on many factors, including how acidic the water is, the chemistry and buffering (reducing the impact) capacity of the soils involved, and the types of fish, trees, and other living things that rely on the water. Dry deposition refers to acidic gases and particles. About half of the acidity in the atmosphere falls back to earth through dry deposition. The wind blows these acidic particles and gases onto buildings, cars, homes, and trees. Dry deposited gases and particles can also be washed from trees and other surfaces by rainstorms. When that happens, the run-off water adds those acids to the acid rain, making the combination more acidic than the falling rain alone. Prevailing winds blow the compounds that cause both wet and dry acid deposition across state and national borders, and sometimes over hundreds of miles. Scientists discovered, and have confirmed, that sulphur dioxide (SO2) and nitrogen oxides (NOx) are the primary causes of acid rain. Acid rain occurs when these gases react in the atmosphere with water, oxygen, and other chemicals to form various acidic compounds. Sunlight increases the rate of most of these reactions. The result is a mild solution of sulphuric acid and nitric acid. Have you ever wondered how acid rain is measured? This is done using a scale called "pH". The lower a substance's pH, the more acidic it is. Pure water has a pH of 7.0 (neutral). Normal rain is slightly acidic because carbon dioxide has dissolved in it, so it has a pH of about 5.5. Acid rain causes acidification of lakes and streams and contributes to damage of trees at high elevations and many sensitive forest soils. In addition, acid rain accelerates the decay of building materials and paints, including irreplaceable (cannot be replaced) buildings, statues, and sculptures that are part of the world's cultural heritage. Before falling to the earth, SO2 and NOx gases and their particulate matter derivatives, sulphates and nitrates, contribute to visibility degradation (lowering) and harm public health. As part of the society, we can do several things about acid deposition. There are several ways to reduce acid deposition, ranging from societal changes to individual action. In order to do this, it is important to understand the causes and effects of acid deposition. To understand these causes and effects and track changes in the environment, scientists collect air and water samples and measure them for various characteristics like pH and chemical composition, and research the effects of acid deposition on human-made materials such as marble and bronze. Finally, scientists work to understand the effects of sulphur dioxide (SO2) and nitrogen oxides (NOx) - the pollutants that cause acid deposition and fine particles - on human health.To solve the acid rain problem, people need to understand how acid rain causes damage to the environment. They also need to understand what changes could be made to the air pollution sources that cause the problem. The answers to these questions help leaders make better decisions about how to control air pollution and therefore how to reduce - or even eliminate - acid rain. Since there are many solutions to the acid rain problem, leaders have a choice of which options or combination of options are best. It may seem like there is not much that one individual can do to stop acid deposition. However, like many environmental problems, acid deposition is caused by the cumulative actions of millions of individual people. Therefore, each individual can also reduce their contribution to the problem and become part of the solution. One of the first steps is to understand the problem and its solutions. *** What you can do Individuals can contribute directly by conserving energy, since energy production causes the largest portion of the acid deposition problem. For example, you can: * Turn off lights, computers, and other appliances when you're not using them. * Use energy efficient appliances: lighting, air-conditioners, heaters, refrigerators and washing-machines. * Only use electric appliances when you need them. * Insulate your home as best as you can. * Use public transportation, or better yet, walk or cycle whenever possible * Be well-informed. |
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| Politics | Produced by Lake House |
Living in a country where agriculture is a main source of income, rain
is considered to play an important role in our lives. You must have heard
about the difficulties people go through, especially in areas such as
Hambantota and Anuradhapura, due to lack of rain. But, sometimes rain can
cause massive damages to humans. Well.. you must be thinking about floods.
Yes, floods cause damage, but today we will be discussing acid rain. 
