MAIN REASONS OF GREEN HOUSE EFFECT

2. GLOBALGLOBAL WARMINGWARMING
• An average increase in theAn average increase in the
temperature of thetemperature of the
atmosphere near the earthatmosphere near the earth’’ss
surface and in thesurface and in the
troposphere1, which cantroposphere1, which can
contribute tocontribute to changes inchanges in
global climate patternsglobal climate patterns

3. CAUSESCAUSES
• Burning of fossil fuels (Coal/Crude oil)Burning of fossil fuels (Coal/Crude oil)
– Power plantsPower plants generate electricitygenerate electricity
– Transportation-----fuels for transports (E.g. LPG,Transportation-----fuels for transports (E.g. LPG,
kerosene, fuel oil)kerosene, fuel oil)
– Industrial processes (E.g. manufacture ofIndustrial processes (E.g. manufacture of
cement, steel, aluminium)cement, steel, aluminium)

4. CausesCauses
• Other greenhouseOther greenhouse
gases emissiongases emission
– AgricultureAgriculture
– ForestryForestry
– Other land usesOther land uses
– Waste managementWaste management

5. Besides carbon dioxide, other
gases such as methane,
chlorofluorocarbons, nitrogen
oxides and ozone also
contribute to the greenhouse
effect.
ExampleExample :: Using natural gas to cookUsing natural gas to cook
CHCH44 + 2O+ 2O22  COCO22 + 2H+ 2H22OO

6. Greenhouse gases in the atmosphereGreenhouse gases in the atmosphere
↓↓
Some infrared radiation is trappedSome infrared radiation is trapped
↓↓
Greenhouse effectGreenhouse effect
Serious greenhouse effect
Global WarmingGlobal Warming

7. How serious theHow serious the
problem is?...problem is?...

8. INCREASEINCREASE IIN GREENN GREEN
HOUSEHOUSE GASESGASES
• Concentration of greenhouse gases inConcentration of greenhouse gases in
the atmosphere is highly increasing bythe atmosphere is highly increasing by
human activitieshuman activities
→→ Leads to the increasing seriousness of globalLeads to the increasing seriousness of global
warmingwarming

10. GLOBAL SURFACEGLOBAL SURFACE
TEMPERATURESTEMPERATURES
–increased about 0.6°C/centuryincreased about 0.6°C/century
since the late19th centurysince the late19th century
–increased to 2°C/century overincreased to 2°C/century over
the past 25 yearsthe past 25 years

11. INCREASE IN GLOBALINCREASE IN GLOBAL
TEMPERATURESTEMPERATURES

12. DIFFERENCEDIFFERENCE
BETWEEN DIFFERENTBETWEEN DIFFERENT
PARTS OFPARTS OF
ATMOSPHEREATMOSPHERE• Troposphere temperatures (the lowest 8Troposphere temperatures (the lowest 8
kilometers of the earth's atmosphere)kilometers of the earth's atmosphere)
collected since 1979 also indicatecollected since 1979 also indicate
warmingwarming
• Cooling effect in higher parts of theCooling effect in higher parts of the
atmosphere: stratospheric temperaturesatmosphere: stratospheric temperatures
have been decreasinghave been decreasing

15. NOT GLOBALLYNOT GLOBALLY
UNIFORM WARMINGUNIFORM WARMING
• Warming parts:Warming parts:
– North AmericaNorth America
– EurasiaEurasia
• Cooling parts:Cooling parts:
– parts of the southeastern U.S.parts of the southeastern U.S.

17. Regional TemperaturesRegional Temperatures

18. SEA LEVELSEA LEVEL
RISINGRISING• Rising at an average rate of 1 - 2Rising at an average rate of 1 - 2
mm/year over the past 100 yearsmm/year over the past 100 years

22. DIRECTDIRECT
TEMPERATURETEMPERATURE
EFFECTSEFFECTS
Increase In Average TemperatureIncrease In Average Temperature
More Extreme Heat Waves During TheMore Extreme Heat Waves During The
Summer; Less Extreme Cold SpellsSummer; Less Extreme Cold Spells
During The WinterDuring The Winter
Harmful To Those With Heart Problems,Harmful To Those With Heart Problems,
Asthma, The Elderly, The Very Young AndAsthma, The Elderly, The Very Young And
The HomelessThe Homeless

24. Extreme EventsExtreme Events
• Extreme Events:Extreme Events:
• Heat waves; Cold waves; Storms; Floods andHeat waves; Cold waves; Storms; Floods and
DroughtsDroughts
Global warmingGlobal warming
An increase in the frequency of extreme eventsAn increase in the frequency of extreme events
More event-related deaths, injuries, infectiousMore event-related deaths, injuries, infectious
diseases, and stress-related disordersdiseases, and stress-related disorders

25. CLIMATE-SENSITIVECLIMATE-SENSITIVE
DISEASESDISEASES• Increase the risk of some infectious diseasesIncrease the risk of some infectious diseases
– [particularly that appear in warm areas; are[particularly that appear in warm areas; are
spread by mosquitoes and other insects]spread by mosquitoes and other insects]
– E.g. Malaria, dengue fever, yellow fever,E.g. Malaria, dengue fever, yellow fever,
encephalitisencephalitis
• Algal blooms occur more frequently asAlgal blooms occur more frequently as
temperatures warm (particularly in areas withtemperatures warm (particularly in areas with
polluted waters)polluted waters)
Diseases (e.g. cholera) accompanying algalDiseases (e.g. cholera) accompanying algal
blooms become more frequentblooms become more frequent

26. AIR QUALITYAIR QUALITY
An increase in theAn increase in the
concentration of ground-concentration of ground-
level ozonelevel ozone
Damage lung tissueDamage lung tissue
Harmful for those with asthmaHarmful for those with asthma
and other chronic lungand other chronic lung
diseasesdiseases

28. Food supplyFood supply
• RisingRising
temperatures andtemperatures and
variablevariable
precipitationprecipitation
• Decrease theDecrease the
production ofproduction of

29. POPULATIONPOPULATION
DISPLACEMENTDISPLACEMENT
Rising sea levelsRising sea levels
Increase the risk of coastal floodingIncrease the risk of coastal flooding
(Necessitate population displacement)(Necessitate population displacement)
• More than halfMore than half of the world's population now livesof the world's population now lives
within 60km of the sea.within 60km of the sea.
• Most vulnerable regions: Nile delta in Egypt, theMost vulnerable regions: Nile delta in Egypt, the
Ganges-Brahmaputra delta in Bangladesh, many smallGanges-Brahmaputra delta in Bangladesh, many small
islands, such as the Maldives, the Marshall Islands andislands, such as the Maldives, the Marshall Islands and

30. UV EXPOSUREUV EXPOSURE
• Skin CancerSkin Cancer
– an abnormal growth of skin tissues.an abnormal growth of skin tissues.
• Premature agingPremature aging
– make the skin thick, wrinkled, and leathery make the skin thick, wrinkled, and leathery
• CataractsCataracts
– No longer have transparent lenses in their eyesNo longer have transparent lenses in their eyes

31. UV EXPOSUREUV EXPOSURE
• Other Eye DamagesOther Eye Damages
– Skin cancer around the eyesSkin cancer around the eyes
– Degeneration of the yellow spotDegeneration of the yellow spot
• Suppression of ImmunitySuppression of Immunity
– Overexposure to UV radiationOverexposure to UV radiation  suppress propersuppress proper
functioning of the body's immune system and naturalfunctioning of the body's immune system and natural
defenses of skindefenses of skin
– UV-B radiation weakens the immune systemUV-B radiation weakens the immune system 
increases the chance of infection and diseaseincreases the chance of infection and disease

32. Measures on controlling theMeasures on controlling the
problemproblem• GovernmentGovernment
* set some* set some lawslaws to limit the amount ofto limit the amount of
pollutants produced by factoriespollutants produced by factories
* develop the* develop the skills of usingskills of using
renewable fuelsrenewable fuels, e.g. solar energy,, e.g. solar energy,
wind energywind energy

33. * Encourage the factories to replace* Encourage the factories to replace
fossil fuels by renewable fuels, whichfossil fuels by renewable fuels, which
would not cause environmental pollutionwould not cause environmental pollution
* Carry out energy saving scheme →* Carry out energy saving scheme →
reduce the pollution produced by burningreduce the pollution produced by burning
fossil fuelsfossil fuels
* Build more plants → reduce the* Build more plants → reduce the
pollutants e.g. COpollutants e.g. CO22
Measures On ControllingMeasures On Controlling
The ProblemThe Problem

34. Measures on controlling theMeasures on controlling the
problemproblem
• CitizensCitizens
** Reduce the use of plastic bags → as burningReduce the use of plastic bags → as burning
plastic emit CH4plastic emit CH4
* Recycle the resources, e.g. plastic* Recycle the resources, e.g. plastic
* Reduce the use of sprays → as CFCs would* Reduce the use of sprays → as CFCs would
be emitted outbe emitted out

35. Measures on controlling theMeasures on controlling the
problemproblem
** Reduce the use of air-conditioner, whichReduce the use of air-conditioner, which
will emit CFCswill emit CFCs
* Use public transportation instead of* Use public transportation instead of
private cars → reduce the pollutantsprivate cars → reduce the pollutants
emitted by carsemitted by cars

36. SourcesSources
• http://www.who.int/globalchange/climate/en/http://www.who.int/globalchange/climate/en/
• http://http://resources.emb.gov.hk/envir-resources.emb.gov.hk/envir-
ed/text/globalissue/e_m2_2_6.htmed/text/globalissue/e_m2_2_6.htm
• http://epa.gov/climatechange/effects/index.htmlhttp://epa.gov/climatechange/effects/index.html
• http://www.tchps.edu.hk/greenweb/greenMaindGhttp://www.tchps.edu.hk/greenweb/greenMaindG
Msg5.htmMsg5.htm
• http://www.ncdc.noaa.gov/oa/climate/globalwarhttp://www.ncdc.noaa.gov/oa/climate/globalwar
ming.htmlming.html

37. THANK
U……U……
ByBy………………
ROHIT ANANDROHIT ANAND