Acid Rain
Acid RainWhere does Acid Rain come from? What are the effects of Acid Rain? What can we do about Acid Rain? These are the three questions I hope to answer today. Acid Rain is a pollutant in our society and can be even seen as synonymous to the word evil, due to the fact that nothing good has come from it. The two primary sources of Acid Rain are nitrogen oxides and sulfur dioxides. They effect our lakes and rivers, trees, buildings and even us. It is a necessity to be aware of the dangers and snares of Acid Rain and it is high time for us to take action and implement courses for correction.
The two primary sources of acid rain are sulfur dioxide (SO2), and oxides of nitrogen (NOx). Sulfur dioxide is a colourless, prudent gas released as a by-product of combusted fossil fuels containing sulfur. A variety of industrial processes, such as the production of iron and steel, utility factories, and crude oil processing produce this gas. In iron and steel production, the smelting of metal sulfate ore, produces pure metal. This causes the release of sulfur dioxide. Metals such as zinc, nickel, and copper are commonly obtained by this process. Sulfur dioxide can also be emitted into the atmosphere by natural disasters or means. This ten percent of all sulfur dioxide emission comes from volcanoes, sea spray, plankton, and rotting vegetation. Overall, 69.4 percent of sulfur dioxide is produced by industrial combustion. Only 3.7 percent is caused by transportation
The other chemical that is also chiefly responsible for the make-up of acid rain is nitrogen oxide. Oxides of nitrogen is a term used to describe any compound of nitrogen with any amount of oxygen atoms. Nitrogen monoxide and nitrogen dioxide are all oxides of nitrogen. These gases are by-products of firing processes of extreme high temperatures (automobiles, utility plants), and in chemical industries (fertilizer production). Natural processes such as bacterial action in soil, forest fires, volcanic action, and lightning make up five percent of nitrogen oxide emission. Transportation makes up 43 percent, and 32 percent belongs to industrial combustion. Nitrogen oxide is a dangerous gas by itself. This gas attacks the membranes of the respiratory organs and increases the likelihood of respiratory illness. It also contributes to ozone damage, and forms smog. Nitrogen oxide can spread far from the location it was originated by acid rain.
Acid rain has drastic effects on our environment. It causes lakes and rivers to become acidic, killing off fish - all the fish in 140 lakes in Minnesota have been killed, and the salmon and trout populations of Norway\’s major rivers have been severely reduced because of the increased acidity of the water. Short-term increases in acid levels kill lots of fish, but the greatest threat is from long-term increases, which stop the fish reproducing. The extra acid also frees toxic metals which were previously held in rocks, especially aluminium, which prevents fish from breathing. Single-celled plants and algae in lakes also suffer from increased acid levels, with numbers dropping off quickly once the pH goes below 5, and by the time the pH gets down to 4.5, virtually everything is dead.
A very highly publicised problem is the effect of acid rain on trees. Conifers appear to be particularly affected, with needles dropping off, and seedlings failing to produce new trees. The acid also reacts with many nutrients the trees need, such as calcium, magnesium and potassium, which starves the trees. The trees are then much more susceptible to other forms of damage, such as being blown down, or breaking under the weight of snow.
Rather surprisingly, the effects of acid rain on trees have overshadowed the effects on people. Many toxic metals are held in the ground in compounds. However, acid rain can break down some of these compounds, freeing the metals and washing them into water sources such as rivers. In Sweden, nearly 10,000 lakes now have such high mercury concentrations that people are advised not to eat fish caught in them. As the water becomes more acidic, it can also react with lead and copper water pipes, contaminating drinking water supplies. In Sweden, the drinking water reached a stage where it contained enough copper to turn you hair green! Slightly more worryingly, that much copper can also cause diarrhea in young children, and can damage livers and kidneys.
A less serious problem is the damage acid rain causes to certain materials, particularly limestone and marble. The acid dissolves the calcium carbonate in the stone, and this solutions evaporates, forming crystals within the stone. As these crystals grow, they break apart the stone, and the structure crumbles.
The best approach to acid rain is to reduce the amount of Nitrogen Oxides and Sulfur dioxides being released into the atmosphere. Fitting a catalytic converter to a car can reduce the emissions of nitrogen oxides by up to 90 percent, but they are very expensive, and cause more carbon dioxide to be released, which contributes to the greenhouse effect.
Sulfur Dioxide emissions from power stations can be reduced before, during, or after combustion.
· If a fuel with a low sulphur content (such as North Sea gas or oil) is burned, not much sulphur dioxide will be formed. However, low sulphur fuels are more expensive because they are in greater demand, and although high-suphur fuels can be treated to reduce their sulphur content, this is very expensive.
· The SO2 created during combustion can be absorbed if an appropriate chemical (such as limestone) is present as the fuel burns.
· Once the fuel has been burned, the SO2 can be removed from the exhaust gases. Most systems spray a mixture of limestone and water onto the gases. This mixture reacts with the SO2 to form gypsum, a useful building material.
Another option is not to burn fossil fuels, but to use alternative energy sources. All these methods for reducing acid gases are expensive, and have drawbacks, so laws have been passed to force businesses to use them. The best way to reduce them is not to use as much energy in the first place. You can help in lots of ways:
· Turn off lights when you leave a room
· If you have a car, don\’t use it for short journeys
· Get your parents to insulate their house properly
· Basically, anything at all that uses less energy
In conclusion, the two primary sources of acid rain is sulfur dioxides and nitrogen oxides. Automobiles are the main source of nitrogen oxide emissions, and utility factories are the main source for sulfur dioxide emissions. These gases evaporate into the atmosphere and then oxidized in clouds to form nitric or nitrous acid and sulfuric acid. When these acids fall back to the earth they do not cause damage to just the environment but also to human health. Acid rain kills plant life and destroys life in lakes and ponds. The pollutants in acid rain causes problem in human respiratory systems. The pollutants attack humans indirectly through the foods they consumed. They effected human health directly when humans inhale the pollutants. Governments have passed laws to reduce emissions of sulfur dioxide and nitrogen oxide, but it is no use unless people start to work together in stopping the release of these pollutants. If the acid rain destroys our environment, eventually it will destroy us as well.