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Introduction|......
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|1.2 Source of information|..
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|2. What is Acid Rain?|...
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|2.1 The definition of Acid Rain|....
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|2.2 How to Measure Acid Rain? |.
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|3. What cause Acid Rain?|....
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|3.1 History of Acid rain|..
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|3.2 Causes of Acid rain|..
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|4. What Are Acid Rain's Effects?|.
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4 Atmosphere|....
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|5. What Society Can Do About Acid|...
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|5.2 Clean up smokestacks and exhaust pipes|.
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Summary
Our environment has been suffering from many problems that have plagued
earth for years. These problems cannot be ignored or it might have
catastrophic results on our environment. Acid rain is a wide spread term
used to describe all forms of acid precipitation, rain snow and dust. Acid
rain is a serious problem with disastrous effects and this problem is
increasing each day.
It causes grave damage to our natural wild and aquatic
life and can also have an adverse effect on human life.
It causes fish and plants to die in waters. As well it causes harm to our
own race as well, because we eat these fish, drink this water and eat these
plants. However acid rain on its own is not the biggest problem. It causes
many other problems such as aluminum poisoning. As Acid rain is a serious
problem with disastrous effects, each day this serious problem increases,
this issue should be met head on and solved before it is too late.
This report focuses on what is acid rain, what cause acid, what are the
effect of acid rain and try to find how to reduce and eliminate Acid rain
causes.
1. Introduction
1.1 Terms of reference
This report was required by Mrs. Daria Hahn, EAP course tutor at
the North Sydney College of TAFE. It is to research what are the
causes and effects of Acid rain, it focuses on how to reduce the
Acid rain effects.
1.2 Source of information
The main sources of the research come from the library in the
North Sydney College of TAFE, which include:
. The Australian Acid rain web site
. Some books on the Acid rain research
. Some article about Acid rain from the Internet and ANZRC
database
2. What is Acid rain?
2.1 The Definition of Acid Rain
According to "acid rain and the facts" (2002, p1) "acid rain is rain, snow
or fog that is polluted by acid in the atmosphere causing damages to the
environment ", 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 effects a variety of plants and
animals. The strength of the effects depend on many factors, including the
level of acid in the water, the chemistry and buffering capacity of the
soils involved, and the types of fish, trees, and other living life 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 then blows these acidic particles and gases onto buildings, cars,
homes, and trees. However, dry deposited gases and particles can be washed
from trees and other surfaces by rainstorms. When that happens, the runoff
water adds those acids to the acid rain, making the combination more acidic
than the falling rain alone.
Figure 1
pic
(http://www.epa.gov/airmarkets/acidrain)
2.2 How to Measure Acid Rain?
Acid rain is measured using a scale called "pH". The lower a substance's pH
is, the more acidic it is. Normal rain is slightly acidic because carbon
dioxide dissolves into it, resulting in a pH of approximately 5.5 while
pure water has a pH of 7.0. (Elsom,1987:p34)
3. Causes of Acid rain
3.1 History of Acid rain
During the 1970s many countries started to notice changes in fish
populations in lakes and damages to certain trees. It was found that the
high acidity levels in the lakes, rivers, bays and streams caused it. Acid
rain was identified to be the major cause of the changes and the damages in
those environments. The USA,Germany,Czechoslovakia,Netherlands,
Switzerland and Australia are countries that have been affected by acid
rain, however, it has also become a problem for Japan, China and Southeast
Asia.
"Ph is measured from Zero to fourteen. On the alkaline side, seawater is
around 8 and at the acidic end Orange juice and soft drinks are around PH2
or 3. Unpolluted rainwater should measure at around PH 5 and any
measurement under 5 would be considered Acid Rain. As Australia is sparsely
populated, its cities are far apart and it has no neighbors, the readings
are not very high. In areas where there are smelters and power stations
however, the problem of acid rain is far greater. The major effects are on
forests and rivers and lakes, where the acid rain causes the soil or water
to be so acidified that trees won't grow or in fact they can even die
completely and rivers and lakes they can become so acidic that they won't
support any sort of aquatic life" (Bubenick, 1984)
3.2 Causes of Acid rain
Cars and trucks are the main sources for the nitric acid that develops into
acid rain. Power generating plants, industrial, commercial and residential
fuel combustion together contributes to most of the rest in the air. The
sulphur dioxide and nitrogen oxides can be transformed into sulphuric acid
and nitric acid, air currents can send them thousands of kilometres from
the source. When the acids fall to the earth in any form it will have large
impact on the growth or the preservation of certain wildlife. Also it might
be capable of causing cancer, birth defects, or genetic imbalances for both
humans and animals (Bown.1990.p:72)
Also these are emitted primarily from utility and also burning wood. 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
sulfuric acid and nitric acid.
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 runoff water
adds those acids to the acid rain, making the combination more acidic than
the falling rain alone. It contains an unnatural acidic. This acidic is not
to be confused with uncontaminated rain that falls, for that rain is
naturally slightly acidic. The acid in the acid rain comes from two kinds
of air pollutants, sulphur dioxide (SO2) and nitrogen oxide (NO x). About
2/3 of all SO2 and 1/4 of all NOx comes from electric power generation that
relies on burning fossil fuels like coal. (Elsom, 1987:92).
4.Effects of Acid Rain
4.1 Water (or fish)
Acid rain in water can affect the fish in two ways: directly and
indirectly. Sulfuric acid directly interferes with the fish's ability to
take in salt, oxygen and nutrients crucial for daily life. Osmoregulation
is the process of maintaining the delicate balance of salts and minerals in
their tissues. For freshwater fish, maintaining osmoregulation is the key
to their survival. Acid molecules, which are a result of acid rain in the
water, cause mucus to form in the fish's gills. This in return prevents the
fish from absorbing oxygen. If the fish are unable to absorb oxygen, the
consequence could be the eventual suffocation of fish and the low pH could
throw off the balance of salts in the fish tissue, salt such as the calcium
(Ca+2. This can result in poor reproduction. The fish's eggs produced would
be damaged, they could either be too brittle or too weak. The decreased
Ca+2 levels also result in weak spines and deformities. Acid Rain has a
detrimental effect when it come to the life of fish, although when nitrogen-
containing fertilizers are washed off into the lakes, the nitrogen
stimulates the growth of algae, which logically would indicate an increase
in oxygen production, thus benefiting the fish. However, because of the
increase in deaths in the fish population due to acid rain,the
decomposition process uses up a lot of the oxygen, which leaves less for
the surviving fish to take in. (Elliot .1984: 156)
4.2 soil
Other issues impacted by acid rain are forests and soil. When acid rain
falls onto the earth's surface it causes a large amount of damage. The soil
is robbed of some vital things. Aluminum that is always present in the soil
is freed, and the roots of trees absorb the toxic element. The trees in
turn are starved and deprived of vital nutrients such as calcium and
magnesium. The Sulfuric acid then returns to earth, when this happens, it
clogs up the stomata in the leaves, stopping photosynthesis. In addition,
severe frosts may also further aggravate this situation. With sulfur
dioxide, ammonia and ozone present in the air, the frost-hardiness of trees
are reduced. Ammonia mixes with sulfur dioxide and forms ammonium sulfate.This product forms on the surface of the trees. When ammonium sulfate
reaches the soils, it reacts to create both sulfuric and nitric acid. Such
conditions also stimulate the growth of fungi and pests like the ambrosia
beetle. When trees are under such stress, they release chemicals such as
terpenes, which attract the ambrosia beetle, which is a serious killer for
forests.4.3 Plant
It also harms vegetation; acid rain damages the protective waxy coat of
leaves. This will interrupt the evaporation of water and air exchange
cycle, so the plants can no longer breath leading to a termination of plant
growth. Toxic metals are further harmful to human health and high lead
levels may harm people who drink the acidic water. Acid rain, acid
fog and acid vapour damages the surface of leaves and needles, reducing a
tree's ability to withstand cold temperature, inhibit plant germination and
reproduction.It can scar the leaves of hardwood forest, wither ferns and
lichens, accelerate the death of coniferous needles, sterilize seeds, and
also weaken the forests to a state that is vulnerable to disease
infestation and decay. Consequently, tree vitality andregenerative
capability is reduced. All this will destroy all the vegetation on the
earth. As a result, there will no longer be a source of food for human
beings to survive on this planet.
4.4 atmosphere
Acid rain also affects the atmosphere. The effects on the atmosphere are
mostly due to dry deposition that was mentioned earlier. The floating
particles can contribute to haze, which effects visibility. This makes
navigation especially difficult for air pilots. The acid haze also inhibits
the flow of sunlight from the sun to the earth and back. Acid rain also
affects architecture. Architecture is affected by both dry precipitation
and wet precipitation. When these particles land on buildings they eat into
the concrete eventually destroying them. This is a potential danger because
the infrastructure of the buildings can be destroyed, thus hurting people
occupying the building. The SO2 and NO2 emissions add to respiratory
problems such as asthma, dry coughs, headaches, and eye, nose and throat
irritations.
5. What Society Can Do About Acid Deposition?
5.1 Understanding acid deposition's causes and effects
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 Acid rain 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. As individuals
people should invest in energy-efficient appliances, avoid the use of air
conditioners, turn off the heater in the evenings, if they have a pool
cover it when it's not in use, also ride a bike or take a bus when
traveling. If every one were to apply these practices to there every day
lives we could reduce the risk of acid rain becoming out of our control. As
a society we can also help by using alternative energy sources. The next
section describes some of the steps that can be taken to reduce, or even
eliminate, the acid deposition problem
5.2 Clean up smokestacks and exhaust pipes
Almost all of the electricity that powers modern life comes from burning
fossil fuels such as; coal, natural gases, and oil. Two pollutants that are
released into the atmosphere, or emitted cause acid deposition, when these
fuels are burned it creates sulfur dioxide (SO2) and nitrogen oxides (NOx).There are several options for reducing SO2 emissions, including using coal
containing less sulphur, washing the coal, and using devices called
scrubbers to chemically remove the SO2 from the gases leavingthe
smokestack. Power plants can also switch fuels; for example burning natural
gas creates less SO2 than burning coal. Certain approaches will also have
additional benefits of reducing other pollutants such as mercury and carbon
dioxide. Understanding these "co-benefits" has become important in seeking
cost-effective air pollution reduction strategies. Finally, power plants
can use technologies that don't burn fossil fuels. Each of these options
has its own costs and benefits, however; there is no single universal
solution. Similar to scrubbers on power plants, catalytic converters reduce
NOx emissions from cars. These devices have been required for over twenty
years, and it is important to keep them working properly and tailpipe
restrictions have been tightened recently. (Bown, 1990:152)
5.3 Use alternative energy sources
There are other sources of electricity besides fossil fuels. They include:
nuclear power, hydropower, wind energy, geothermal energy, and solar
energy. Of these, nuclear and hydropower are used most widely; wind, solar,
and geothermal energy have not yet been harnessed on a large scale in
Australia.There are also alternative energies available to powerautomobiles,
including natural gas powered vehicles, battery-powered cars, fuel cells,
andcombinationsofalternativeandpoweredgasolinevechiles.
All sources of energy have environmental costs as well as benefits. Some
types of energy are more expensive to produce than others, which means that
not all people can afford all types of energy. Nuclear power, hydropower,
and coal are the cheapest forms today, but changes in technologies and
environmental regulations may shift that in the future. All of these
factors must be weighed when deciding which energy source to use today and
which to invest in for tomorrow
In summary Acid rain is a huge environmental concern. It causes damages to
our lakes, our rivers, our wild life and most importantly human life. Acid
rain is absorbed in fruits, and in the tissues of animals. Although these
toxic metals do not directly affect the animals, they have serious affects
on humans when they are being consumed. . It also causes other problems,
such as the release of aluminium and lead into our water supplies causing
suffering to human life. Acid rain is a real threat for human beings and
the environment. In many countries they have set different procedures to
prevent acid rain and even as individuals it's still possible to fight acid
rain. The amount of pollution released must be reduced. However it will
take time; even if the pollution were to be stopped today the problem would
not end for years to come because of the build up in the soil.
Bibliography
1.Acidrainandthefacts(2002)
http://www.ec.gc.ca/acidrain/acidfact.html.(Online accessed 02 April 2004)
2.Acidrainbackground(nd).http://www.plehigh.edu/~kaf3/books/reporting/Acid.html. (Online accessed 02 April 2004).3. Acid rain topics (nd) http;//www.doc.mmu.ac.uk/aric/eae/acid_rain/older/
print/
acid_rain_introduction.html. (Online accessed 02 April 2004).4Acid rain - what's being done? What can we do? (2002). http://www.ec.gc.ca/acidrain/done-you.html (Online accessed 02 April 2004).5.Bown, W.(11Aug1990) "Europe's forests fall to acid rain". New Scientist.(Vol. 127, p. 17) New York
6.Elliott, C., Robert, G. (Editors). (1984) The Acid Rain Sourcebook. New
York: McGraw-Hill, Inc.7.Elsom, d (1987). Atmospheric Pollution, Basil Blackwell Ltd, UK.8. Bubenick, D.(1984) Acid rain information book.Longman.sydney
