acid rain

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-:NO-:NOx:-x:-

-:SO-:SOx:- x:-

-:GROUP-B:-

-:Contents:- Introduction.Introduction.History.History.Causes.Causes.Affected Areas.Affected Areas.Effects On Living Organisms.Effects On Living Organisms.Effects On Ecosystem E Materials.Effects On Ecosystem E Materials.Controlling Measures.Controlling Measures.

-:Introduction:-

MSN Encarta

-:Acid Rain:-• Acid rain is a popular term refining to the deposition of wet(rain, snow, fog and dry acidic components.• A more accurate term is acid deposition.• Wet deposition.• Dry deposition

-:Formation of Acid Rai:-

-:Formation of Acid Rain:-

• Distilled water has a neutral PH of 7. Liquids with pH less than7 are acidic

and those with a PH greater than 7 are alkaline.

• Acidic rain has a Ph of 5.6 to 5.7.• CO2 and H2O reacts to form the

carbonic acid that can ioniz in water. ( H2CO3)________(H+) +(HCO3-)

• Pollutants from a source of pollution drift up to the atmosphere. Once in the atmosphere, the pollutants combine with moisture to form acid rain. The acid rain is collected in a cloud and will be released when it rains.

-:Formation:-

-:History:-• In 18521852 he reported the relationship

between acid rain and atmospheric pollution.

• After 19601960scientists began observing and studying phenomenon.

• Harold Harvey of Canada Harold Harvey of Canada was among the first to research a dead lake in USUSA public awareness of the problem was heightened in 1990 1990 after the New York New York times .

-:History:-• Ph readings in rain and fog is

below 2.4 2.4 have been reported

in industrial areas it is a

problem in RussiaRussia and China.China.

• Acid rain was first observed

by RobertRobert Angus Smith Angus Smith in

Manchester England.Manchester England.

-:Acid Rain In US:-• In 1991, NAPAP 1991, NAPAP provided its

first assessment of acid rain in the US.US.

• In 2007,IN USA 2007,IN USA total SOSO22 emissions were 8.9 million 8.9 million tonstons, achieving the program's long term goal ahead of the 2010 2010 statutory deadlinestatutory deadline.

-:Acid Rain In -:Acid Rain In Canada:-Canada:-• In 1994, Canada 1994, Canada and the provinces

began working with stakeholders to develop new national acid rain strategy since the 20 kg/ha/ye 20 kg/ha/ye deposition target. .

• These negotiations resulted in a series of international agreements over the years that followed, beginning with the 1979 UNECE1979 UNECE

-:Causes:-• Emission from volcanoes.• Acid producing gases are also

created by biological process on land, wet land and oceans.

• The major biological source is dimethyl sulfide.

• Bacterial decomposition and lighting also contribute to the acid rain.

-:Human activities:-

• Coal burning.• Extraction of metals.• Industrial emissions.• Electric power plants.• Nuclear power plants.

-:Anthropogenic sources:-

• Automobiles produce 1/2 world NOx.

• SO2 cause 70% of acid rain.• Livestock are responsible for

2/3 of all sources of NH3

which causes acid rain.

-:Affected Areas:- -:Canada:- • Acid rain is a problem in Canada• Water and soil systems lack natural

alkalinity such as lime base.• Cannot neutralize acid.• Canada consists of susceptible hard

rock such as granite.• Do not have the capacity to effectively

neutralize acid rain.

CanadiaCanadian n

forestsforests

Jizera Jizera mountain in mountain in

PolandPoland

-:Affected Areas:-

• China, Eastern Europe and Russia are the areas, most effected by acid rain.

• The forests of upstate New York and New England.

• This shows that the effects of acid rain can spread over a large area, far from the source of the pollution.

TaiwaTaiwann

ChinChinaa

U.S

U.KU.K

-:Effects On Aquatic Life:-• Continual acid rain decrease the PH level

and increase the “Al” level.• Such factors cause chronic stress That kill fish or may lead to:1. Lower body weight.2. Smaller size.3. Less able to compete for food. 4. Less able to compete for habitat.

• It disturbs fish ability to maintain “Ca” level.

• Eggs of fish become weak and brittle.

• Actual threat is from long term increase which stops the fish from reproducing.

Death of fish due to acid rain.

Survival Of Aquatic Species -:w.r.t to Acid Rain:-

-:Effects On Plants:-Dissolve the toxic substances.“Al” get absorbed by roots.It corrodes waxy protective coatings

of leaves.Making plants susceptible to

diseases.Cause slower growth, injury or

death of forest.

-: Effects On Human Beings:-

Not direct effect on human.

It causes skin infections:

a. Irritation to face.Irritation to face.

b.b. Skin allergy. Skin allergy. It may causes

Asthma.

-:Effects of Acid Rain – Materials:-

• Destroy the historical monuments made up of limestone and marble.

• Increase oxidation of Cu+2 and bronze• Accelerates weathering in metal and

stone structures Eg. Parthenon in Athens, Eg. Parthenon in Athens,

Greece,TajMahal in Agra, India.Greece,TajMahal in Agra, India.

Sandstone figure(Castle Sandstone figure(Castle Westphalia) Westphalia) corrode by acid rain corrode by acid rain

-:1908:- -:1969:--:1908:- -:1969:-

-:Effects On Ecosystem:-• Biological organisms and

Environment in which they are live are called as the “Ecosystem”.“Ecosystem”.

• At pH 5pH 5, most fish eggs cannot hatch.

• At lower pH levels, some adult fish adult fish and organisms die.

• Some acid lakes acid lakes have no aquatic life.

-:Acid Rain on the Forest Floor:-

• A spring shower in the forest washes leaves and falls through the trees to the forest floor below.

• This is major cause of forest death.

-:-:Preventions and Preventions and Solutions:-Solutions:-• 1 CLEAN UP SMOKE STACKS AND

EXHAUST PIPES:-Almost all the electricity that power

modern life comes from burning fossil fuel such as coal, natural gas and oil.

-Coal accounts for most SO2SO2 emission and a large portion of NOXNOX emissions.

Reduction of sulpher:Reduction of sulpher:a.Using coal with less sulfur. b.Washing the coal.c.Burning natural gas creates less SO2.SO2.

-:Use alternative -:Use alternative energy sources:-energy sources:-

• There are other sources besides Fossil fuel.

• They include :They include :1.Nuclear power.2.Wind power.3.Solar energy.4.Geothermal energy.5.Hydropower.

Wind Wind energenergy y

Solar Solar energenergyy

-:Restore a damaged environment:-

-Acid deposition penetrates deeply into the fabric of an ecosystem changing the chemistry of soil and stream.

-It takes many years for ecosystem to recover from acid deposition, even emissions are reduced.

-Limestone or lime can be added to acidic lakes to cancel out the acidity.

- The process called liming has been extensively used in Norway and Sweden

-: Take action as individuals:-

Individuals can contribute in this case:Individuals can contribute in this case:-Buy vehicles with low NOXNOX emission.-Keep your thermostat at 68 degree F in

winter and 72 degree F 72 degree F in summer.-Promote awareness of the issue.- Install pollution control equipment.