green house effect

8/8/2019 Green House Effect .

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The Earth

The Atmosphere

Sun

Our Earth receive most of its energy,

called radiation, from the Sun.


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This Energy is electromagnetic radiationin the visible spectrum, with small amounts of

IR and UV radiations.


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The incoming solar energy has a very short wavelength

and passes through the atmospheric gases unaffected to reach

the Earths surface.


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The Earths surface absorbs the

solar energy and release it back

to the atmosphere as infrared(IR)

radiation, some of which goes

back to space.

IR radiation

(heat)


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IR radiation

(heat)


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IR radiation

(heat)

Some of the IR radiations emitted

by the Earth is absorbed by gases

in the atmosphere that re-emit the

energy as the heat back towards

the Earths surface.


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Three main gases in our atmosphere that

contribute to green house effect are

CO2,methane and water .

Carbon

dioxide

methane

water


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These gases absorb the infrared radiation emitted by

the earth and re-radiate the energy as heat back

towards the earth,causing a warming known as thegreen house effect.

infrared

Absorbing IR radiation.


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With increasing CO2 emissions

from humans,the green house effect

has become drastically exagerrated

This has caused a dangerous

global warming process that is

threatining our current

environment by melting polarice caps and raising see levels

around the globe


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GREEN HOUSE EFFECT:GREEN HOUSE EFFECT:--

natural process that createsnatural process that creates

moderate temperatures on earthmoderate temperatures on earth

to which life has adaptedto which life has adapted

-- Beneficial for sustaining life on earth.Beneficial for sustaining life on earth.


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-Natural

greenhouse effect.

-man-madegreenhouse

effect(enhanced).


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MECHANISM OF GREENMECHANISM OF GREEN

HOUSE EFFECT :HOUSE EFFECT :-- Solar energy reaches earth surface .Solar energy reaches earth surface .

30% directly reflected.30% directly reflected.

Atmosphere absorbs the rays which wereAtmosphere absorbs the rays which were

not reflected in space.not reflected in space.

20% is absorbed by green house gases20% is absorbed by green house gases

in atmosphere.in atmosphere.


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Part of absorbed rays byPart of absorbed rays byearth brings warmth, inearth brings warmth, in

turn directed inturn directed inatmosphere in form ofatmosphere in form ofinfrared rays.infrared rays.

By receiving energyBy receiving energydirectly from sun,greendirectly from sun,greenhouse gases absorbhouse gases absorbinfrared rays .infrared rays .

Heat is reHeat is re--directed indirected inevery direction;particularlyevery direction;particularlyearth .earth .


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Greenhouses are structures designed to retain heat.Greenhouses are structures designed to retain heat.

Look like small glass houseLook like small glass house

Greenhouses are used to grow plants, especially in thewinter.

Greenhouses work by trapping heat from the sun.

The glass panels of the greenhouse let in light but keep heatfrom escaping.

This causes the greenhouse to heat up.

The heat-trapping ability of a greenhouse is influenced by anumber of factors including the transparency of thegreenhouse cover, color of the surfaces inside thegreenhouse, and type of surfaces inside.


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The Earths atmosphereis all around us. It is the

air that we breathe.

Greenhouse gases inthe atmosphere behave

much like the glasspanels in a greenhouse.

Sunlight enters theEarth's atmosphere,passing through theblanket of greenhousegases.


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As it reaches the Earth's surface,land,water, and biosphere absorb the sunlights

energy .

Once absorbed, this energy is sent backinto the atmosphere.

Some of the energy passes back into

space, but much of it remains

trapped in the atmosphere by the

greenhouse gases, causing our world

to heat up


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WHAT FACTORS IMPACTWHAT FACTORS IMPACT

GREEN HOUSE EFFECT .?GREEN HOUSE EFFECT .? The earth's atmospheric "greenhouse

effect" is a complex ..

Earth temperature depends on greenEarth temperature depends on green

house effect,amount of heating andhouse effect,amount of heating and

cooling are strongly influenced by severalcooling are strongly influenced by several

factors.factors. ALBEDOALBEDOpercentage of solar energypercentage of solar energy

reflected by a surface.reflected by a surface.


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Factors influencing earthFactors influencing earth

albedo:albedo:-- CloudsClouds

SurfaceSurface

OceansOceans

Forested areaForested area


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CAUSES :CAUSES :--

Increase in the quantity of green house gases.Increase in the quantity of green house gases.

The natural causes of the Green house effectThe natural causes of the Green house effect

are the emissions of gases like nitrous oxide,are the emissions of gases like nitrous oxide,carboncarbon--dioxide, methane, ozone and waterdioxide, methane, ozone and watervapour.vapour.

manman--made causes of the Green House effect ismade causes of the Green House effect isdeforestation .deforestation .

Burning of gasoline.Burning of gasoline.

Population growthPopulation growth


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GREEN HOUSE GASES:GREEN HOUSE GASES:--

Carbon dioxideCarbon dioxide -- 53%53%

MethaneMethane -- 17%17%

0zone0zone -- 13%13%

Nitrous oxideNitrous oxide 12%12%

CFCsCFCs 5%5%


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EMISSION ORIGIN:EMISSION ORIGIN:--

CARBON DIOXIDE:CARBON DIOXIDE:--

burning of fossilburning of fossil

energies,massive destruction of tropicalenergies,massive destruction of tropicalforest.forest.

METHANE:METHANE:--

breeding of ricebreeding of riceculture,garbage dump,exploitation ofculture,garbage dump,exploitation ofpetroleum and gaspetroleum and gas


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OZONE:OZONE:--

transformation of exhaust gases.transformation of exhaust gases.

NITROUS OXIDE:NITROUS OXIDE:--

agricultural fertilizers.agricultural fertilizers.


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Contributers toContributers to

Greenhouse Effect :Greenhouse Effect :-- The greenhouse gasesThe greenhouse gases

include water vaporinclude water vapor

with three atoms ,with three atoms ,

ozone , carbon dioxide ,ozone , carbon dioxide ,and methane. Also,and methane. Also,

trace quantities oftrace quantities of

chlorofluorochlorofluoro--carbonscarbons

can have acan have adisproportionately largedisproportionately large

effect.effect.


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ROLE IN CLIMATEROLE IN CLIMATE

CHANGE :CHANGE :-- Enhanced greenhouse effectEnhanced greenhouse effectincreaseincrease

in radiative forcingin radiative forcingincrease CO2 level.increase CO2 level.

Increased CO2 levelIncreased CO2 leveladditionaladditional

absorption and emission of thermalabsorption and emission of thermalinfraredinfrarednet warming.net warming.


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WHAT IS BEING DONE TOWHAT IS BEING DONE TO

REDUCE GLOBALW

ARM

ING:REDUCE GLOBALW

ARM

ING:-- by reducing dependence on fossil fuels,by reducing dependence on fossil fuels,

increasing the use of renewable energy,increasing the use of renewable energy,

expanding forests,expanding forests,

and making lifestyle choices that help toand making lifestyle choices that help tosustain the environment.sustain the environment.

..


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warmer,hotter climate conditions.warmer,hotter climate conditions.

Desertification and soil erosion willDesertification and soil erosion will

increase.increase. Coastal areas more proan to flooding.Coastal areas more proan to flooding.

Tropical storms and hurricanes.Tropical storms and hurricanes.

Health diseases like chronic .Health diseases like chronic .

Insect carrying diseases like malaria.Insect carrying diseases like malaria.

Marine life will be affected.Marine life will be affected.


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Positive effects :Positive effects :--

Milder climate conditions make survivalMilder climate conditions make survival

possible.possible.

Plant productivity would increasePlant productivity would increasebiodiversity.biodiversity.

We wont freeze to death .We wont freeze to death .


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Increase in temperatureIncrease in temperature global warming.global warming.

Melting of permafrost would release moreMelting of permafrost would release more

methanemethane

Species like polar bear,seals areSpecies like polar bear,seals are

becoming extinct.becoming extinct.

Native people finding it harder to hunt .Native people finding it harder to hunt .

Herbivores would need to change theirHerbivores would need to change theireating patternseating patterns change in biodiversity ..change in biodiversity ..

green house effect

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