The ozone layer & Its Importance

The PPT Brief About the Ozone Layer?,
Where it is located?,
Why It is Important?
Why it is depleting?,
What are the effects of the Ozone Depletion?,
What to be done to save the ozone layer ?.

1. THE OZONE LAYER
BY
MR. NIKESH BANWADE
ENVIRONMENT DEPARTMENT
SAURASHTRA CEMENT LIMITED
THE PRESENTATION
ON

2. CONTENT OF THE PRESENTATION
Whatisit??
Whereisit?
WhyisitimportanttolifeonEarth?
Why it is depleting
What are the effects of the Ozone layer Depletion ?
How can we save it

3. WHAT IS THE OZONE?
Ozone(O3)moleculesconsistofthreeoxygenatomsthat
formswhenfreeOxygenmoleculesbondtoO2
molecules.
Thisgasisextremelyrareintheatmosphere,
representingjustthreeoutofevery10million
molecules.
Ozoneishighlycorrosiveandtoxicandisusedasa
disinfectant.
Ozonegascanbecreatedordestroyedbythesun’s
UltraVioletrays.

4. THE OZONE –WHERE IT IS ?
Ninetypercentofozoneexistsintheupperatmosphere,
orstratosphere,between10and50kmabovetheearth.
Itisthinnestaroundtheequatoranddenseratthe
poles.
Itcanbefoundinsmallconcentrationsinthe
tropospherewhereitisconsideredapollutantorBad
Ozone
Ozone levels are reported in Dobson Units (DU) & 300
DU is an average value.

5. “Smog” Ozone
Ozone Amount
Altitude (Kilometers)
“Good Ozone”
“Bad Ozone”
GOOD AND BAD OZONE
TheOzonefoundat
StratosphereisaGood
Ozoneasitabsorbthe
harmfulUVraysofSun
Theozonefoundat
TroposphereisaBad
Ozoneasitistoxicand
affectsonthehumans&
plants.

6. OZONE FORMATION
WhenanOxygenmoleculeabsorbsaPhotonofLightwithawavelengthshorterthan
200nanometers(1Billionofmeter)theenergysplitsthemoleculeintotwoOxygen
atoms.OneoftheseatomscanreactwithanotheroxygenmoleculetoformanOzone
Molecule.

7. 78%nitrogen
20.6%oxygen
<1%argon
0.4%watervapor
0.036%carbondioxide
Tracesgases:
Ne,He,Kr,H,O
3
Methane,NitrousOxide
Argon (0.934%)
Water Vapor (0.4%)
CO2 (0.035%)
Neon (0.00182%)
Helium (0.000524%)
Methane (0.00015%)
Krypton (0.000114%)
Hydrogen (0.00005%)
N2O (0.00003%)
Ozone (0.000005%)
CFCs (0.0000001%)
COMPOSITION OF EARTH’S ATMOSPHERE

8. WHY OZONE LAYER IS IMPORTANT
Onadailybasis,thesunradiatesitsenergy
towardEarth.Oneformofthisenergyis
UltraVioletradiation,alsoknownasUVrays.
UVraysarerelativelyhighenergywavesthat
provideEarthwiththewarmthitneedstosupport
lifeasweknowit.
UVrayspenetratetheEarth’satmosphereat3
slightlydifferentwavelengthscalledUV-A,UV-B,
andUV-Crays.

9. WHY OZONE LAYER IS IMPORTANT
ThestratosphericozonelayercompletelystopsthepenetrationofUV-Craysand
eliminatesmostoftheUV-Brays.
Therefore,theozonelayerprotectslifeonEarthfromtheharmfuleffectsofsolar
radiationonadailybasis.

10. OZONE LAYER DEPLETION
Since1928,Chlorofluorocarbonshavebeenproduced,originallyas
nonflammablerefrigerantsforuseinrefrigerators,andeventuallyfor
useinfireextinguishers,drycleaningagents,pesticides,degreasers,
adhesives,andaspropellantsforaerosolproducts.
ChorofluroCarbon(CFCs)leakfromequipment,getmixedinthe
atmosphere.CFCsareextremelystable,sotheydonotreactwith
othersubstancesintheatmosphere,Ithaveanestimatedlifespanof
morethan100years
CFCstravelaroundforyears,climbhigherandhigher,upto10kmor
So

11. OZONE LAYER DEPLETION
Attheheighofabov10KM,thesunisstrongenoughtobreakdowntheCFCmolecules
Thefreedchlorineatomsreactwithozoneinacatalyticprocess
Chlorine atoms reacts with radicals of oxygen Generated from Ozone.
The Ozone depliting process is described below

12. As these CFCs have been released into the atmosphere, the level of ozone
in the stratosphere has decreased.
One chlorine atom from CFC can destroy up to 100,000 ozone atoms in a
catalytic process
As a result, continuous deplition of the ozone in the stratospere created
the hole in ozone layer “OZONE HOLE“
OZONE LAYER DEPLETION

13. OZONE HOLE
TheOzoneHoleisDiscoveredfirstin”in1985.
Consideredasoneofthiscentury’smajorenvironmentaldisasters.
Thelandareaundertheozonedepletedatmosphereincreasedsteadilytomore
than20millionsq.km.intheearly1990sandhasvariedbetween20and25
millionsq.km.
In2008,theareaoftheozoneholereachedarecord29millionsq.km.
The2010reportfound,"Overthepastdecade,globalozoneandozoneinthe
ArcticandAntarcticregionsisnolongerdecreasingbutisnotyetincreasing
Agradualtrendtoward"healing"wasreportedin2016-17

14. OZONE HOLE

15. DEPLETING THE OZONE LAYER
MEANS :
MoreUV-Bradiationtoreachtheearth.
MoreUV-Bmeans
Moremelanomaandnon-melanomaskincancers
Morecancers
Moreeyecataracts
Weakenedimmunesystem
Reducedplantyields
Damagetooceaneco-system
Reducedfishingyields
Adverseeffectsonanimals
Moredamagetoplasticequipment&materialetc……

16. OZONE DEPLETION AFFECTS
GLOBAL WARMING AND CLIMATE
CHANGE?
Asozonelevelsinthestratospherearedepleted,moresolarradiationpenetratesthe
Earth’satmosphere.
ThisaffectresultsinanincreaseinsolarradiationreachingtheEarth’ssurfaceadding
toanincreaseinsurfacetemperature.
Inturn,globalwarmingactuallyresultsinawarmingofthetroposphere,butacooling
ofthestratosphere,hinderingtheozonelayer’snaturalchemistryforrepairs.

17. Ozone depletion : What to do?

18. MONTREAL PROTOCOL
Afterthediscoveryofozonedepletioninthelate1970’s,manycountriesagreedthatsomething
mustbedoneworldwidetostoptheproductionofman-made,ozoneharmfulproducts.
TheinternationalcommunityadoptedtheViennaConventionin1985followedbytheMontreal
Protocolin1987.
Protocolonsubstancesthatdepletetheozonelayerwasadoptedon16/09/1987,Governments
recognizedtheneedforstrongermeasurestoreducetheproductionandconsumptionofCFCs.
Thelatestreportsconfirmthatithasledtothephasingoutofabout95%oftheconsumptionof
ozone-depletingsubstances(ODS)listedintheagreement.Inturn,thishasledtotheprospectof
theozonelayerrecoveringby2050to2075.

19. HOW YOU CAN CONTRIBUTE ?
Household Products
MostmodernhouseholdproductsdonotcontainCFCs,butsomemay.
Buyair-conditioningandrefrigerationequipmentthatdonotuseHCFCsasrefrigerant
Manyaerosols,cleaningsolventsandfoamblowingagents(suchasfireextinguishers)usedto
containCFCsandoccasionallystilldo.
BuyaerosolproductsthatdonotuseHCFCsorCFCsaspropellants
TheUnitedNationsEnvironmentProgramreleasesalistofchemicalproductsthatcontain
substancesthatdepletetheozonelayer,aswellasalternativeproductsthatdonotharmthe
ozonelayer.

20. HOW YOU CAN CONTRIBUTE ?
Refrigeratorsandfreezers,especiallythosemanufacturedbefore1995,oftencontain
CFCs.Air-conditioningunitsanddehumidifiersmayalsocontain
hydrochlorofluorocarbons,whichdepletetheozonelayer.
Forexistingair-conditioningandrefrigerationappliancesthatoperateonHCFCsorCFCs,
therefrigerantshouldberecoveredorrecycledwheneveranoverhaulofequipmentis
tobecarriedout.
Replacingorretrofittingsuchequipmenttooperateonnon-HCFCsrefrigerantshould
alsobeconsidered.

21. HOW YOU CAN CONTRIBUTE ?
Conductregularinspectionandmaintenanceofair-conditioningandrefrigeration
appliancestopreventandminimizerefrigerantleakage.
Whenmotorvehicleair-conditionersneedservicing,makesurethattherefrigerants
areproperlyrecoveredandrecycledinsteadofbeingventedtotheatmosphere
SafedisposalofoldappliancespreventsCFCsandHCFCsfrombeingreleasedintothe
environment.

22. “Bethechangeyouwanttoseeinothers”
Childreneducation
Awakeningadults
PlantmoretreesandSaveexistingplantation
Whatcanwedo,asconcernedcitizens,toensurethatour
childrenhaveaviableplanettoinhabit
HOW YOU CAN CONTRIBUTE ?

23. HOW YOU CAN CONTRIBUTE ?
SAVE TREESPLANT TREES
“ The best time to plant a tree was twenty years ago.
The second best time is NOW….”
Why Plant Trees?
Thesimpleactofplantingatree,helpsthe
environmentinsomanyways.
Filterpollutionfromair
Helprecyclewater
Preventsoilloss
Createshade
Giveshelterfromwindandrain
Providehomesforanimals
Makefoodforhuman&life
Provideaninterestinglearning
environmentforchildren&others

24. SAVE OZONE LAYER
SAVE EARTH, IT’S A ONLY PLANET WE HAVE
THANK
YOU
“Earth provides enough to satisfy every man's needs,
but not every man's greed.” ―Mahatma Gandhi