The atmosphere

The atmosphere protects the earth from the sun's harmful rays. Shooting stars from space, which can be seen on a clear night, burn up when they enter the atmosphere. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation).

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Troposhere

Stratosphere

Ionosphere

The stratosphereThe stratosphere is a layer of Earth's atmosphere. The stratosphere is the second layer, as one moves upward from Earth's surface, of the atmosphere. The stratosphere is above the troposphere and below the mesosphere.Ozone, an unusual type of oxygen molecule that is relatively abundant in the stratosphere, heats this layer as it absorbs energy from incoming ultraviolet radiation from the Sun.

The ionosphere

The ionosphere is a part of the upper atmosphere, comprising portions of the mesosphere, thermosphere and exosphere, distinguished because it is ionized by solar radiation. It plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on the Earth. In ionosphere we find the Ozone layer

Air is made up mostly of Nitrogen and Oxygen.When we breathe we use Oxygen and give off Carbon Dioxide. The plants and trees absorb the Carbon Dioxide and give off Oxygen.

What is air?

This layer is the nearest to the earth surface,that's why most effects on our life depends on it.Among them the most harmful ones are the acid rains and the greenhouse effect.

Ozono is a gas found 10 to 15 kilometers above the Earth. It protects us from the sun's harmful ultra violet rays .

The ozone layer can be damaged by pollution, especially CFC's found in Aerosols

Look out for 'environmentally friendly 'and ' ozone friendly' Products.

The cause ofOzone Layer Depletion

Chluorofluorocarbons (CFCs), such as frigerants and propellants in Aerosolcans, release chlorine when they break down.

Rising to the upper Atmosphere, the chlorine reacts with ozone (O

3) gas, reducing it to O

2 gas.

The ozone layer in the upper atmosphere protect life on earth from the harmful ultraviolet rays in sunlight.

Multinational agreement was reached in 1987 to phase out the use of these chemicals. However quantities of these chemicals already in the air would continue to deplete the ozone layer for decades.

Carbon dioxide and other gases added toatmosphere may cause global warming

Carbon dioxide and other gases added toatmosphere may cause global warming

The addiction of CO2 to the atmosphere by cellular respiration roughly balances the removal

of carbon dioxide by photosynthesis.

COCO 22

All fossil fuels and many other fuels contain carbon.As these fuels are used they are releasing more and more

carbon dioxide into the atmosphere.

sunsun

Carbon dioxide takenin by plants for

photosynthesis

Carbon dioxide takenin by plants for

photosynthesis

plantsplants

Animals and humans

Animals and humans

respirationrespiration

Fossil fluesFossil fluesHuman energy useHuman energy use

Carbon dioxideReleased intoatmosphere

Carbon dioxideReleased intoatmosphere

dead materialdead material

Carbon dioxide and other gases added to the atmosphere may Carbon dioxide and other gases added to the atmosphere may cause global warming.cause global warming.

The rise of the agriculture and the Industrial Revolution triggered some profound environmental changes. A change that could alter the entire biosphere is rapid global warming.The addition of CO2 to the atmosphere by cellular respiration roughly balances the removal of CO2 by photosynthesis. What is troubling is the current rate of increase in atmospheric CO2.

Carbon DioxideOther Gases

Carbon Dioxide is one of several so-called greenhouse gases (molecules that can trap heat and cause atmospheric warming, known as greenhouse effect). CO2 absorbs infrared radiation and slows its escape from Earth.

Other greenhouse gases are methane and nitrous oxide, both of which are also increasing in the atmosphere as a result of fossil-fuel consumption, industry and agriculture.

Fossils fuels power most of our industries, agricultural equipementsand automobiles and they heat most of our homes.

One of the major side effects of the combustion of fossil fuels is an increase in atmospheric CO2

We must stop chopping down the rain forests as many rare species will become extinct and life giving oxygen which is produced by the trees will be reduced.

In addition to flooding, a warming trend might alter patterns of global precipitation. For instance, the grain belts of the central United States and centra Asia might

become much direr and unable to support the crops currently grown there. Furthermore, forested areas in seminarid zones could lose their trees and become

deserts.

Studies of climatic changes through geological time

mathematical models lead some

climatologists to predict that in the

next 50-100 years, at the present rate

greenhouse gases are increasing,

atmospheric temperatures could

rise by about 2-5°C. It is also possible that

as the temperature of the atmosphere

increases, populations of soil

bacteria will increase and in turn produce even more CO2 and

methane.

Acid rain is produced when poisonous gases from power stations and cars react together and dissolve in rainwater . The resulting rain and snow is often as strong as lemon juice. This rain kills trees , dissolves stones on historic buildings , enters rivers and streams and kills the fish.

Emissions of the gases and nitrogen oxides contribute to the international problem of acid rain pollution . Sulphur dioxide emissions arise during combustion of fossil fuels . Including coal , oil and natural gas . Oxidation of sulphur dioxide forms Sulphur dioxide (SO2), a colourless gas. It is soluble in water and it is transformed into sulphuric acid (H2SO4), which falls as acid precipitation or 'acid rain'.Large quantities of sulphurDioxide are released naturally when volcanoes erupt. The problem of acid rain is not a recent development,but we are much more aware of the damage caused by acid rain nowadays.

The Acropolis was built over 2000 years ago. The damage done is largely due to the pollution caused by cars and other vehicles in Athens -the most polluted city in Europe . Car engines burn petrol as a fuel and release acidic gases such as sulphur dioxide into the atmosphere. May other countries have also noticed an acceleration of damage to their cultural heritage.

How can pollution problems How can pollution problems cause acid raincause acid rain?

About 8080% of the air is nitrogen.The high temperatures cause some of this nitrogen oxides to produce nitrogen oxides.These are some of the ways levels of nitrogen oxides can be reduced:

In power stations Eliminate excess air by using the minimum amount of air needed for combustion Lower the combustion temperature

In cars: Change the air Recirculate exhaust fumes Use catalytic converters

These are some ways we can reduce levels of sulphur dioxide in the air:

Burn less fossil fuel Fuel desulphurisation Sulphur reduction during combustion by the addition of lime to coal duriing combustion Fuel gas removal

How to treat damaged areas

Fertilise damaged conifer forests with calcium,magnesium,potassium,zinc and manganese.Spread lime on affected lakes and forest.

Acid rain causes a variety of effects that harm or kill individual fish and reduce fish population numbers. In some cases,acid rain completely eliminates some fish species from certain bodies of wother and resultes in decrased biodiversity. As racid rain flows through soils, aluminum is released from the soli into the lakes and streams, resulting in a lower ph and a higher alluminium level. Low ph and increased aluminium levels are directly toxic to fish and cause them chronic stress.

How does acid rain affect fish and other aquatic organisms?

SPECIESOF ANIMALSAND PLANTS

Some types of plants and animals ar able to tolerate acidic waters. Others, however, are acid-sensitive and will die as the ph falls. Generally, the young of most species are more sensitive to envionmental conditions than adults.

BIOLOGICAL INDICATORS: SIGNS OF PULLUTION Biological indicators are useful for assessing

levels of pollution

1. Lichens are sensitive to sulphure dioxide. By observing the type of lichens growing locally, environmental scientists can monitor the level of sulphur dioxide pollution. 2. Mosses are sensitive to air pollution and have disappeared from many metropolitan and industrial areas

Don't throw rubbish on the floor

Don't use the car when you can walk or cycle: use public

transport

DON'T HAVE A BATH, HAVE A SHOWER!

SHARE A CAR WITH FRIENDS Home

BUY LOCAL FOOD, EAT FRUIT AND VEGETABLES IN THEIR SEASON.

Home

Recycle paper, glass, plastic and reuse.

Don't waste waterturn tap off, don't leave water on.

Switch lights off when you leave a room use less electricity

Don't leave appliances stand-by

Use only “Ozone Friendly” products