Friday, January 15, 2010

How to Avoid Acid Rain

Acid rain is a popular phrase used to describe rain, snow, fog, or other precipitation that is full of acids that collect in the atmosphere due to the burning of fuels such as coal, petroleum, and gasoline. Acid rain was first recognized in Europe in the late 1800s but did not come to widespread public attention until about 1970, when its harmful effects on the environment were publicized. Research has shown that in many parts of the world, lakes, streams, and soils have become increasingly acidic, prompting a corresponding decline in fish populations. Acid rain occurs when polluted gases become trapped in clouds that drift for hundreds, even thousands, of miles and are finally released as acidic precipitation. Trees, lakes, animals, and even buildings are vulnerable to the slow, corrosive effects of acid rain.

Acidification, the process of making acid, is not just caused by deposits of acidic rain but also by chemicals in snow and fog and by gases and particulates when precipitation is not occurring. The major human-made causes of acid deposition are (1) emissions of sulfur dioxide from power plants that burn coal and oil and (2) emissions of nitrogen oxides from automobiles. These emissions are transformed into sulfuric acid and nitric acid in the atmosphere, where they accumulate in cloud droplets and fall to Earth in rain and snow, wet deposition. Other sources of acid deposition are gases like sulfur dioxide and nitrogen oxides, as well as very small particulates. These gases and particulates are usually deposited when it is not raining or snowing which is called dry deposition.

While large areas of Europe and North America are exposed to acidifying depositions, only certain types of ecosystems are affected by these depositions. The most vulnerable ecosystems usually have a thin cover of soil, containing little calcium and sitting upon solid rock made up of hard minerals such as granite or quartz. Many freshwater lakes, streams, and rivers have become acidic, resulting in the decline or local destruction of some plant and animal populations. It is not yet certain that land-based ecosystems have been affected by acidic deposition. After acid rain was discovered in Europe, scientists began measuring the acidity of rain in North America. Initially, they found that the problem was concentrated in the northeastern states of New York and Pennsylvania because the type of coal burned there was more sulfur containing.

Acid rain is measured through pH tests that determine the concentration of hydrogen ions in a liter of fluid. The pH scale is used to measure acidity or alkalinity. It runs from 0 to 14. Water has a neutral pH of 7. The greater the concentration of hydrogen ions and the lower the pH number, the more acidic a substance is and the lower the concentration of hydrogen ions and the higher the pH number, the more alkaline or basic a substance is. So a pH greater than 7 indicates an alkaline substance while a pH less than 7 indicates an acidic substance. It is important to note that a change of only one unit in pH equals a tenfold change in the concentration of hydrogen ions. For example, a solution of pH 3 is 10 times more acidic than a solution of pH 4. Normal rain and snow measure about pH 5.60. In environmental science, the definition of acid precipitation refers to a pH less than 5.65.

Measured values of acid rain vary according to geographical area. When pH levels are drastically upset in soil and water, entire lakes and forests are endangered. Evergreen trees in high elevations are especially vulnerable. Although the acid rain itself does not kill the trees, it makes them more susceptible to disease. Also, high acid levels in soil cause leaching of other valuable minerals such as calcium, magnesium, and potassium. Small marine organisms cannot survive in acidic lakes and rivers, and their depletion affects the larger fish who usually feed on them, and, ultimately, the entire marine-life food chain. Snow from acid rain is also damaging; snowmelt has been known to cause massive, instant death for many kinds of fish. Some lakes in Scandinavia and New York's Adirondack Mountains are completely devoid of fish life. Acid rain also eats away at buildings and metal structures. From the Acropolis in Greece to Renaissance buildings in Italy, ancient structures are showing signs of corrosion from acid rain. In some industrialized parts of Poland, trains cannot exceed 40 miles (65 kilometers) per hour because the iron railway tracks have been weakened from acidic air pollution. Usually, waters affected by acid rain are treated by adding limestone or lime, an alkaline substance (base) that reduces acidity. Fishery biologists especially are interested in liming acidic lakes to make them more habitable for sport fish. In some parts of Scandinavia, for instance, liming is used extensively to make the biological damage of acidification less severe.

While neutralizing ecosystems that have become acidic, treats the symptoms but not the sources of acidification. Although exact sources of acid rain are difficult to pinpoint and the actual amount of damage caused by acid deposition is uncertain, it is agreed that acid rain levels need to be reduced. Scientific evidence supports the notion that what goes up must come down, and because of public awareness and concerns about acid rain in many countries, politicians have begun to act decisively in controlling or eliminating human causes of such pollution. Emissions of sulfur dioxide and nitrogen oxides are being reduced, especially in Western Europe and North America. For example, in 1992 the governments of the United States and Canada signed an air-quality agreement aimed at reducing acidifying depositions in both countries. While countries in Western Europe and North American have actively carried out actions to reduce emissions of gases leading to acid deposition for a number of years, countries in other parts of the world have only recently addressed the issue. In Eastern Europe, Russia, China, India, Southeast Asia, Mexico, and various developing nations, acid rain and other pollution problems are finally gaining notice. For example, in 1999, scientists identified a haze of air pollution that hovers over the Indian Ocean near Asia during the winter. The 3.8 million-square-mile haze (about the size of the combined area of all fifty American states) is made up of small by-products from the burning of fossil fuels. Such a cloud has the potential to cool Earth, harming both marine and terrestrial life.

What Is Acid Deposition?

Acid deposition is the depositing of acid in any form on objects in the environment, be they natural or manmade. In most cases, the acid deposition commonly takes the form of acid rain, which often gets the most attention because it is perceived as being the most dangerous. Other forms include both solids and gasses and, while they may not pose as much risk, they can still be detrimental to objects they touch.

In order for deposition to take place, the acid must first be present in the atmosphere. This most commonly occurs from the burning of coal at electrical generation plants. The coal produces a substance known as sulfur dioxide. Once in the air, it mixes with other elements, mainly oxygen, to become sulfuric acid. Some of this material eventually falls to the Earth.

Acid rain is simply acid deposition in liquid form. The sulfuric acid is found in clouds, which condense and the water droplets eventually become so heavy that they fall. The acid rain can actually fall many miles from where the actual coal plant is located, simply because of wind patterns, and the time it takes the acid to form and fall.

Acid deposition can also happen through the form of acid particulates, which are solids, and acidic vapors, which are gasses. As the acid makes its way back to the planet’s surface, it lands on other objects, such as buildings, trees and lakes. In most cases, these objects are not prepared to deal with the introduction of higher acid levels and therefore are negatively affected.

The main damage is done to buildings and cars, as well as trees and water systems, such as lakes and rivers. Acid deposition can strip paint off buildings and cars, and even lead to structural deterioration. In forests, it can cause trees to die in great numbers as the plants try to cope with a different pH than they prefer. The same is also true of water systems, where fish and other wildlife can be harmed because of the acid deposition.

Stopping acid deposition has therefore become a major concern for many of the world’s countries. Though it may not be possible to completely eradicate coal plants in the near future, switching to cleaner forms of energy without coal, or even using clean coal technologies, can help. For example, acid deposition can be nearly eradicated through the use of scrubbers that remove sulfur from the emissions that coal plants produce.

What Are the Best Acid Rain Solutions?

Acid rain solutions focus on both prevention, and on helping to deal with the environmental ramifications once the acid rain does take place. So little can be done after the fact to improve the environment that the best acid rain solutions often focus on making sure it never happens in the first place. To do this, it is first necessary to identify the causes of acid rain together with processes that can be changed to aid in prevention.

Acid rain is caused by sulfur emissions, which are put into the air through the burning of coal, often used for energy. Other sources of sulfur in the atmosphere include volcanoes and decomposing vegetation. Despite the fact these natural sources do exist, it is generally agreed that anthropogenic causes are the main sources of acid rain. This may make acid rain solutions easier to identify simply because if humans have caused it, then logically they should have the ability to change it.

The best acid rain solutions focus on power plants and coal used in the production of energy. Technologies exist that can remove sulfur from the emissions coming out of coal plant. Low-sulfur varieties of coal can also be used to reduce sulfur emissions. Often, a combination of these acid rain solutions provides the best way to minimize the problem.

The installation of scrubbers can help prevent as much as 95 percent of sulfur emitted by a carbon-fired electric power plant. The scrubbers work by spraying water with lime through the gas emission produced from burning the coal. The lime interacts with the sulfur dioxide, creating a sludge that is then captured and stored. The problem with this method is that retrofitting existing power plants with the technology is usually very expensive. It is cheaper if the technology is installed as the power plant is being built, and the inclusion of the technology is now required in many countries when new power plants are erected.

Acid Rain Solutions

The numbers of potential solutions for acid rain that are accessible to us are aplenty. What matters more is to intentionally enforce these solutions to stop acid rain and to do soon a wide scale. People all over the world should be made aware of the causes and effects of acid rain, and they should be carefully educated about it. Solutions to stop acid rain can only be successful through mutual cooperation. Given below are a few acid rain solutions, which can seriously reduce the threat of acid rain, if strictly followed by a large number of people.

* One of the most fundamental acid rain solutions is to utilize fuels that burn more cleanly, or to burn coal more efficiently. This will greatly reduce the possibilities of acid rain developing in the atmosphere.

* As fas as industrial power plants are apprehensive the best solution is to attach devices known as 'scrubbers' in the chimneys of these plants. These scrubbers reduce the amount of sulfur produced in the smoke by 90 - 95%.

*Vehicles and cars must be mandatory necessary to comply with very tight and efficient emission standards. Fitting catalytic converters into the exhaust pipes of vehicles also reduces the amount of sulfur dioxide produced by the vehicles.

*We can make a lot of changes on a personal level as well, in order to combat acid rain. We should contain the use of our cars and vehicles and utilize other modes of transportation on a more normal basis. We should also remember to turn off all our lights and electrical devices in case we are not using them.

*For industrial power plants, there are many more acid rain solutions that must be compulsory as they are clearly the biggest contributors to the formation of acidified water droplets in the atmosphere. Industries must regularly inspect and clean all their emission equipment and chimneys and pipes.

*All these acid rain solutions will be pointless unless people are informed and educated about the ill-effects and harms of acid rain. A common and nationwide effort must be made to make people aware. Only after that is done will all the acid rain solutions actually make a difference.

Acid rain is one of the biggest ecological hazards that we are facing today, and strong measure must be taken to prevent it, before it is too late. Governments need to sit up and take notice, and do much more than what they are already doing. Acid rain adversely affects plants, animals and human beings, and as a result it is not something that we can afford to ignore. It is our duty towards ourselves and towards our fellow human beings to do all we can to prevent and reduce the existence and increase of acid rain in our environment.