极地上空的臭氧空洞-保护环境.ppt

1 Jan 10 2003 localnoon Kiruna Sweden 2 Jan 14 2003SouthernNorway 3 PolarStratosphericOzone Dr PaulA Newmanhttp code613 3 gsfc nasa gov People Newman NASA sGoddardSpaceFlightCenterIPYWebcastNASAGSFCNov 3 2008 4 OzoneBasicFacts O3 Ozoneiscomposedof3oxygenatoms O3concentrationsaresmall peakconcentrationsareabout10partspermillionatanaltitudeofabout32km 20miles O3absorbsharmfulsolarultravioletradiation Anecessaryconditionforlife O3ismainlyfoundinthethestratosphere O3atthegroundisaproblem Inhalationofozoneforverysmallconcentrationscancauselungproblems Mass BillionMetricTons Sun1 9900 000 000 000 000 000Earth5 980 000 000 000Globalatmosphere5 300 000Globalozone3 5 AtmosphericComposition Nitrogen78 1 Oxygen20 9 Argon0 9 Water1 4 tropics 0 2 poles 0 0004 stratosphere CO20 0360 O30 001 stratosphere 0 00001 troposphere 6 Troposphere Stratosphere Mesosphere Thermosphere AtmosphericStructure 7 Troposphere Stratosphere Mesosphere Thermosphere AtmosphericStructure Airlinersflyat30 000 40 000feet 8 Troposphere Stratosphere Mesosphere Thermosphere AtmosphericStructure ER 2fliesat70 000feet 9 Troposphere Stratosphere Mesosphere Thermosphere AtmosphericStructure 10 Ozone partspermillion Troposphere Mesosphere Thermosphere OzoneFacts 90 ofozoneisinthestratosphere 0 2 4 6 8 11 Ozone partspermillion Stratosphere Mesosphere Thermosphere OzoneFacts 0 2 4 6 8 10 ofozoneisinthetroposphere 12 Digression DobsonUnits ozonelayer 3mm 300DobsonUnits TotalOzoneisameasureofthetotalcolumnamountaboveus MeasuredinDobsonUnitsIfwebringalloftheozoneaboveusdowntotheEarth ssurfaceThethicknesswouldbeabout3millimeters 0 1inches 300DobsonUnits approximatelytheglobalaverage 100DobsonUnits 1millimeterinthickness TheDobsonUnitisaconvenientunitofmeasurementfortotalcolumnozone 2 10 13 Ozone partpermillion Stratosphere OzoneFacts 0 2 4 6 8 UVc 100 Absorption UVb 90 Absorption UVa 50 Absorption Scattering OzoneistheEarth snaturalsunscreen 14 UVHealthFacts UVpluses producesvitaminDintheskin necessarytomaintainlevelsofcalciumandphosphorus 10 15minutestwiceaweek UVminuses Eyedamage cataracts photokerititus snowblinding ocularcancersSkincancers basal squamous melanomaphotoagingDamagetovariouslandspeciesDamagetoaquaticspeciesIncreasedpollutionlevelsinurbanenvironments Cataract Melanoma MexicoCity 15 Largepolarozonelossesresultfromchlorineandbrominecompoundsthataremainlyhumanproduced 16 ChlorinePathway 17 SourceGases ClismuchmoreabundantthanBr but Brisabout60timesmoreeffectiveatO3destruction FromOzoneFAQ seehttp www unep org ozone faq shtml 18 AtmosphericChlorineTrendsfromNOAA ERL ClimateMonitoringDivision UpdatedFiguremadebyDr JamesElkinsfromTrendsoftheCommonlyUsedHalonsBelowPublishedbyButleretal 1998 AllCFC 113fromSteveMontzka flasksbyGC MS andrecentupdatesofallothergasesfromGeoffDutton insituGC 50years 102years 5years 42years 85years CFC 11 CCl4 CFC 113 CFC 12 CH3CCl3 19 PolarStratosphericClouds Central SwedenJanuary14 2003 P Newman 20 Solomonetal 1986 WofsyandMcElroy 1986 andCrutzenandArnold 1986 suggestreactionsoncloudparticlesurfacesasmechanismforactivatingChlorine Cl2iseasilyphotolyzedbyUV blue greenlightHNO3issequesteredonPSC Antarcticozoneholetheory 21 PolarOzoneDestruction 1 O3 Cl ClO O2 Onlyvisiblelight blue green neededforphotolyzingClOOClNooxygenatomsrequiredNet 2 O3 h 3 O2 2O3 3O2 3 ClOOCl h 2Cl O2 2 2ClO M ClOOCl M 22 AntarcticMeasurements AuroraoverHalleyBayStation Antarctica 75 6 S26 5 EBruntIceShelf CoatsLand105daysofcontinuousdarkness twiceperyearre supplyPopulation 65insummer 15inwinter 23 OctoberAntarcticOzonepre 1985 24 OctoberAntarcticOzone 25 TOMS August31 2003 10 25 2008 26 OzoneHoleArea N America 27 OctoberAverageOzoneHole 28 MarchAveragetotalozone 29 Arctic AntarcticTrends 30 What sbeingdone 31 WhatCanYouDo Avoidexcessivesolarexposure limitsunbetween11AMand2PM Wearandencourageotherstowearsunscreen SPFratingof15 Evenwithsunscreen prolongedexposureisnotsmart Checkyourskinregularly WearsunglassesthatscreenUV HatsandothercoveringsMakenoteoftheUVindexonthenewsorweb http www epa gov sunwise uvindex html 32 AtmosphericChlorineTrendsfromNOAA ERL ClimateMonitoringDivision UpdatedFiguremadebyDr JamesElkinsfromTrendsoftheCommonlyUsedHalonsBelowPublishedbyButleretal 1998 AllCFC 113fromSteveMontzka flasksbyGC MS andrecentupdatesofallothergasesfromGeoffDutton insituGC 50years 102years 5years 42years 85years CFC 11 CCl4 CFC 113 CFC 12 CH3CCl3 10 25 2008 33 AntarcticEESC Obs Projections UsingWMOscenarioA1 adj wecanprojectforwardfrom1980toshowrecoveryofEESCaround2065 34 Ozonefuture Projectedareaoftheozonehole 35 Summary StratosphericozoneisacriticalgasforscreeningsolarUVradiation Humanproduced