ozone layer and green house eefect,

7/28/2019 Ozone Layer and Green House Eefect,

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THE OZONE LAYER, THE

GREENHOUSE EFFECT, AND GLOBAL

WARMINGBYBAZIRA HENRY J12B27/103

OTRITIA ANGELLO UBBI J12B27/609

OTEKAT SONI JACKLINE J12B27/605NAMEE SARAH J12B27/504

UMULISA PROSSY J12B27/861

NASEJJE JUSTINE J12B27/505


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THE OZONE LAYER

Ozone (O3) is a gas that occurs naturally in theatmosphere.

This gas is most concentrated in the ozone

layer.The ozone layer is located in the stratosphere

several miles above the surface of the earth.

Although the ozone layer represents only asmall fraction of the gases present in theatmosphere, it plays a vital role in shielding theearth from ultraviolet light from the sun.


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Ozone layer formation


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Importance of the ozone layer

Shield the earth from ultra violet radiation

Without the ozone layer U.V light would come

direct to the earth leading to the following;

1. diminishing of fish stocks

2. reduction in agriculture production

3. skin cancers4. damages building materials


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Ozone layer depletion


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Causes of ozone layer depletion

The main cause of ozone depletion is theaccumulation of various pollutants in theatmosphere e.g

CFCs ( BCFS and halons )have been used inrefrigeration, insulating foam and asindustrial solvents.

They are exposed to the air and transportedby wind.


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Consequences of ozone depletion

More harmful UV rays get to the earth which

has the potential to cause more skin cancers.

Rice crops could be affected by ozone

depletion. They depend on cyanobacteria for

retention of nitrogen. Cyanobacteria are verysensitive to UV light, so the increase might kill

them.


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Consequences continue..

Plankton are also sensitive to UV light and

could become extinct if UV light levels are too

high.

It is harmful to human health in the

troposphere, as it can cause asthma attacks.

It also affects rubber in car tyres.


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Actions taken to protect the ozone

layer

Through an international agreement known as

the Montreal Protocol on Substances that

deplete the Ozone Layer,

Governments have decided to eventually

discontinue production of CFCs, halons,

carbon tetrachloride, and methyl chloroform

(except for a few special uses), and

developed more "ozone-friendly" substitutes.


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Actions taken continue

The ozone layer is expected to recover over

the next 50 years or so

The Kyoto, Japan protocol calls for 5%

reduction in carbon emissions bellow 1990

levels by 2012

It has two major options;

1.cap and trade control(pay for pollution)

2.voluntary limits(caring for the others)


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The Green house effect.

Heating of the earth as a result of green house

gases.

The mechanism is named after the effect of

solar radiation passing through glass and

warming a greenhouse.

The sun emits radiation of short wavelengths

and high frequencies to the earth.

The earths surface emits infrared radiation of

long wavelengths and low frequencies.


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GAS SOURCES % CONTRIBITION TO OZONE

DEPLETION

CARBONDIOXIDE (Co2 fossil fuels, deforestation,

cement production, plant

decay, vehicles. 64%

METHANE Anerobic decay of plants,

natural gas wells, ruminant

animals 19%

NITROUS ACID vehicles, soil denitrification,

plant decay. 6%

SULPHUR HEXA FLOURIDE power plants, industries,

volcanoes, fossil fuels. 4%

CHLOROFLOROCARBONS .deforestation, fossil fuels, use

of chlorinated compounds. 11%


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Mechanism of Green house effects.

As the suns rays travel through the atmosphere:

Some energy is reflected back to space.

Some is absorbed by clouds and gases likeozone.

Some is reflected from the surface back to

space

On average about 51% of the suns radiation

reaches the earths surface.


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Importance of the Greenhouse Effect

It regulates the temperature of the earth andthe atmosphere.

The energy that reaches the earths surface isused in a number of processes e.g. heating of

the ground surface, evaporation of water andplant photosynthesis.

However, the industrial revolution and human

activities e.g. the burning of fossil fuels andclearing of forests have greatly intensified thenatural greenhouse effect causing globalwarming.


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The green house effect


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Global Warming

This refers to the arising average temperature

of the earths atmosphere and oceans;

it started to increase in the 19th century and is

projected to keep going up.

Since the early 20th century, Earth's average

surface temperature has increased by about

0.8 C (1.4 F), with about two thirds of the

increase occurring since 1980 .


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Global warming cont...

.

it is caused by increasing concentrations of

greenhouse gases produced by human

activities such as deforestation and burning

fossil fuels o 6.4 C for their highest.
http://en.wikipedia.org/wiki/Greenhouse_gashttp://en.wikipedia.org/wiki/Deforestationhttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Fossil_fuelhttp://en.wikipedia.org/wiki/Deforestationhttp://en.wikipedia.org/wiki/Greenhouse_gas


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Short term effects of global warming

Rise in the sea levels

Change the amount and pattern of

precipitation

Expansion ofsubtropicaldeserts.

Retreat of glaciers, permafrost and sea ice
http://en.wikipedia.org/wiki/Precipitation_(meteorology)http://en.wikipedia.org/wiki/Subtropicshttp://en.wikipedia.org/wiki/Deserthttp://en.wikipedia.org/wiki/Retreat_of_glaciers_since_1850http://en.wikipedia.org/wiki/Permafrosthttp://en.wikipedia.org/wiki/Sea_icehttp://en.wikipedia.org/wiki/Sea_icehttp://en.wikipedia.org/wiki/Permafrosthttp://en.wikipedia.org/wiki/Retreat_of_glaciers_since_1850http://en.wikipedia.org/wiki/Deserthttp://en.wikipedia.org/wiki/Subtropicshttp://en.wikipedia.org/wiki/Precipitation_(meteorology)


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Long term consequences

Extreme-weather events including heat waves,

droughts and heavy rainfall,

Species extinctions due to shifting

temperature regimes,

Changes in crop yields.

Acidic rains

Skin cancers
http://en.wikipedia.org/wiki/Extreme-weatherhttp://en.wikipedia.org/wiki/Heat_wavehttp://en.wikipedia.org/wiki/Extinction_risk_from_climate_changehttp://en.wikipedia.org/wiki/Crop_yieldhttp://en.wikipedia.org/wiki/Crop_yieldhttp://en.wikipedia.org/wiki/Extinction_risk_from_climate_changehttp://en.wikipedia.org/wiki/Heat_wavehttp://en.wikipedia.org/wiki/Extreme-weatherhttp://en.wikipedia.org/wiki/Extreme-weatherhttp://en.wikipedia.org/wiki/Extreme-weather


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Solutions to Global Warming

Controlled deforestation

Development of wind power plants.

Energy generation using wind turbines.

Utilizing geothermal energy for power,

heating, and cooling.

Recycling wastes.

Advancement in Solar Energy Technology


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Impending policy issues on global

warming in Uganda

Tree planting

Changing transport means (adopting bicycles)

Fighting of traffic jam in Kampala

Turning off heat after use.

Use of much cleaner fuels if affordable

Recycling of waste

Use of energy saving options for cooking andlighting


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References

ENVIRONMENTAL SCIENCE, A GLOBAL

CONCERN 11th, 6th and 4th EDITIONS.

Greenleapdelhi.com

http://zebu.oregon.edu

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