Air Pollution

Air Pollution

Air Pollution is not a new topic. It is a problem that we have noticed since the industrial revolution, when trees, houses and cars were covered in soot from the factories. People demanded change then, just as they are demanding it now. With all the talk of acid rain, global warming and ozone depletion it seems hopeless, but it isn't. Everyone can make a difference. After reading this you will understand the causes, effects and possible solutions to the problems of acid rain, global warming and ozone depletion. You will also see that things are bad but not hopeless.

Acid Rain is the term given to any precipitation that is above normal acidity, this includes snow and fog. The acidity or causticity of a solution is measured in pH. A neutral pH is 7, acidic is lower then 7 and a base is greater than 7. The normal pH of rainwater is 5.5 (slightly acidic). In Scotland on April 20, 1974 the rain measured 2.4 and in West Virginia in 1978 the rain had a pH of 2.0! This was in the 70's and air pollution since then hasn't gotten any better. This very highly acidic rain kills plants and animals and destroys buildings.

Acid rain occurs when the moisture in the air mixes with Carbon, Nitrogen, and Sulphur gases. These gases are released into the air by the burning of fossil fuels (natural gas, coal and oil). The primary source of the gases comes from electric companies that burn coal.

Damage caused by acid rain is tremendous. The acid in the rain bonds with the minerals in the soil, tying them up so that plants can not use them. The plant becomes mineral deficient and weak. The rain also kills the plant's leaves, further weakening it and making the plant more susceptible to fungus and other diseases. This is a major agricultural problem.

The rain effects lakes, rivers and the animals living within them. The plants in the lakes and rivers are killed in the same way as land plants. The fish and other animals are left with no food. The animals that do survive are killed from the metals being drawn into the water from the soil, when the acid bonds to them.

Many architectural structures are destroyed from the acid rain. Most of the cement used to make our buildings. are made from lime which is very reactive with acid. You can see the effects of this weathering if you look at old gravestones or statues. The words etched in some of the gravestones can barely be read anymore because they are so worn away. Weathering is a natural process. Rain is normally slightly acidic but because of air pollution and the higher acidity of the rain, the process is sped up greatly.

Industry is looking for solutions to the air pollution problem. The best solution would be to stop burning fossil fuels all together but at this time we have no other alternatives. Scientists are trying ways to cut down on pollution. One way is to wash the coal before they burn it. Washing it takes off most of the sulphur but not all of it. The rest would have to be removed chemically but this process is still being researched. The problem with this is what to do with all the excess sulphur. Another solution is to clean the smoke before it is released into the air. Many filters have been installed in smoke stacks but again this solution is not 100% effective.

Another major environmental problem caused by air pollution is global warming or the "greenhouse effect". The greenhouse effect is caused by solar energy being trapped by CO2, Methane, Ozone (O3), Nitrous gas, and Chlorofluorocarbons (CFCs) that are in the air. The solar energy comes into the atmosphere as light, it hits the Earth, looses some of its energy and becomes heat. Because the heat does not have as much energy it can not penetrate back through the blanket of gases. The Earth has a natural greenhouse effect caused by the CO2 in the atmosphere. If we didn't have this natural greenhouse effect, the Earth would be too cold to live on. We have increased this effect through the release of all the gases I have mentioned above.

CO2 is released into the air from factories and from the exhausts of cars. Some of this CO2 in the atmosphere is used when the plants make their food but with many of our forests being cut down it makes our problems worse. CFCs are released into the air from aerosol cans. They are also used in air conditioners and refrigerators and leak from these places. Ozone is