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Air Polution Essay Research Paper Acid rain

Air Polution Essay, Research Paper

Acid rain is a problem that has plagued earth for years. It is poisoning our waters,

animals, plants, soil, and more. It is a problem that can not be ignored or it might have

catastrophic results on our environment. Acid rain is caused by air pollution, which is

due to man-made actions.

Scientists have discovered that air pollution from the burning of fossil fuels is the

major cause of acid rain. Power plants and factories burn coal and oil, which is used to

produce the electricity we need to heat and light our homes and to run our electric

appliances. We also burn natural gas, coal, and oil to heat our homes, and our cars,

trucks, boats, and airplanes use gasoline to run, which is another fossil fuel.

The smoke and fumes from burning fossil fuels rise into the atmosphere and combine

with the moisture in the air to form acid rain. The main chemicals in air pollution that

create acid rain are sulfur dioxide and nitrogen oxides. Acid rain usually forms high in the

clouds where sulfur dioxide and nitrogen oxides react with water, oxygen, and oxidants.

This forms a mild solution of sulfuric acid and nitric acid. Sunlight then increases the rate

of these reactions. Rainwater, snow, fog, and other forms of precipitation containing

those mild solutions of sulfuric and nitric acids fall to the earth as acid rain.

Acid rain is a much more complex problem then most people realize. Acid rain

does not only drop dangerously high levels of acid into the ground directly affecting

wildlife but it also mixes with other elements and compounds in the earth which then

become harmful to the environment. For example aluminum is one of the most common

metals on earth. It is stored in a combined form with other elements in the earth. When it

is combined it cannot dissolve into the water and soil and harm the fish and plants.

However the acid from acid rain can easily dissolve the bond between these elements.

The Aluminum is then dissolved into a more soluble state by the acid. Other metals such

as copper and iron are similarly affected however it is the aluminum that is the most

common. In this form it is easily absorbed into the water. When it comes in contact with

fish it causes irritation to the gills. This irritation in turn causes fish to create a film of

mucus in the gills to stop this irritation until the irritant is gone. However the aluminum

does not go always and the fish continues to build up more and more mucus to counteract

it. Eventually there is so much mucus that it clogs the gills. When this occurs, the fish can

no longer breath. It dies and then sinks to the bottom of the lake. Scientist predict that

acid rain is one of the leading causes the possible extinction of fish. This does not only

affect the fish in the water, it affects everything including humans. These lakes and

streams are not just homes for aqualife but they are our sources of water too.

Another very large problem is the effect of acid rain on trees. When a tree?s roots

absorb water from the ground it is taking in its source of life, and when acid rain rains

around that tree, its life source is poisoned. Tree?s leaves and needles begin to drop off,

and seedlings fail to produce new trees. The acid also reacts with many nutrients the trees

need, such as calcium, magnesium and potassium. This starves the trees, and they

become much more susceptible to other forms of damage, such as being blown down, or

breaking under the weight of snow. Also forests in high mountain regions receive

additional acid from the acidic clouds and fog that often surround them. These clouds and

fog are often more acidic than rainfall. When leaves are frequently bathed in this acid fog,

their protective waxy coating can wear away. The loss of the coating damages the leaves

and creates brown spots. When the leaves are damaged, they cannot produce enough food

energy for the tree to remain healthy.

Acid rain does not only poison our drinking water, but it is very corrosive. Acid

rain is known to contribute to the corrosion of metals and deterioration of stone and paint

in buildings, statues, and other structures of cultural significance. Human-made materials

gradually deteriorate even when exposed unpolluted rain, but acid rain accelerates the

process. For example, the Capitol building in Ottawa has been disintegrating because of

excess sulfur dioxide in the atmosphere. Limestone and marble turn to a crumbling

substance called gypsum upon contact with the acid, which explains the corrosion of

buildings and statues. In addition, bridges are corroding at a faster rate, and the railway

industries as well as the airplane industry have had to put more money in repairing the

corrosive damage done by acid rain. Not only is this an economically taxing problem

caused by acid rain, but also a safety hazard to the general public. In 1967 the bridge over

the Ohio River collapsed killing 46 people, the reason was corrosion due to acid rain.

Dry deposition of acidic compounds can also dirty buildings and other structures, leading

to increased maintenance costs.

Also, there is growing concern about the potential health risks associated with acid rain.

Recent reports suggest, for example, that downwind derivatives of sulfur dioxide, known

as acid aerosols, may pose serious health threats throughout the eastern United States.

Inhalation of acid aerosols may lead to bronchitis in children and decreased lung function

in adults, particularly asthmatics. Controlling acid rain will play an important role in

reducing these risks. In Europe there have already been several birth defects that have

been.

So what is being done to fix our problem with acid rain? The EPA or

Environmental Protection Agency in 1990 had a clean air law passed. This law is a

program designed to significantly reduce acid rain. The overall goal of the ARP (Acid

Rain Program) is to achieve significant environmental and public health benefits through

reductions in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOX), the primary

causes of acid rain. The program encourages energy efficiency and pollution prevention.

The Acid Rain Program began with the reduction of SO2 emissions by 10 million tons

below the 1980 levels. To achieve these reductions, the law requires a two-phase

tightening of the restrictions placed on fossil fuel-fired power plants. Phase 1 began in

1995 and has had very positive results. Phase 2 is scheduled to start in the year 2000.

The Acid Rain Program?s other half was the reduction of NOX. Program focuses on one

set of sources that emit NOX, coal-fired electric utility boilers, the same as the SO2

program. Similar to the SO2 emission reduction requirements, the NOX program is

implemented in two phases, beginning in 1996 and 2000. This program puts very strict

limitations on these boilers.

The problem of acid rain can not only be fixed by putting limitations on these

huge boilers, this just slows down the process of the destruction acid rain does. The only

way to stop burning these electric utility burners is to find a way to replace them. That is

why scientists the world over have been looking for alternative sources of power. There

are other sources of energy besides fossil fuels. These include hydroelectric power and

nuclear power. Dams use the power of water to turn turbines and make electricity. People

have been using this form of energy for most of this century. Nuclear power plants make

electricity from the energy released by splitting atoms. A small amount of nuclear fuel

can make a very large amount of electricity.

There are problems with using hydroelectric and nuclear power. Hydroelectric plants

require a constant source of water. Since rainfall is not always predictable, hydroelectric

plants are not as reliable as those using coal or oil are. Hydroelectric plants can also harm

the environment. Thousands of acres of land often have to be flooded to create a

reservoir, a holding place for the great amounts of water needed to power these plants.

Sometimes the land that would be flooded is home to rare types of plants or animals.

Nuclear power plants produce electricity cheaply. But the nuclear waste they leave

remains dangerous for thousands of years.

Scientists are looking at other energy sources, such as windmills and solar energy, using

the power of the sun itself. In several states, there are modern windmills like airplane

propellers that make energy from the wind. In other places, wind power pumps water

from the ground. In Arizona and New Mexico, solar energy is at work making electric

power. Each of these sources has drawbacks as well. Windmills and solar panels are

reliable only where it is windy or sunny most of the time. All sources of energy have

benefits and limitations, including the cost of producing the energy. All of these factors

must be weighed when deciding which energy source to use.

Thus, it is seen that the rectification of the very pressing issue of acid rain should be one

of Mankind?s greatest goals. There are too many possible solutions and alternatives to

endanger the world with this dangerous risk to humanity?s environment, buildings and

accomplishments, and water supply. Through even more litigation and law enforcement,

and the many other alternative solutions, the Earth can be saved from this severe threat.




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