Scientific Assessment of the Ozone Layer Depletion: 2022

WorldMeteorologicalOrganization OzoneResearchandMonitoring–GAWReportNo.278 SCIENTIFICASSESSMENTOFOZONEDEPLETION 2022 WorldMeteorologicalOrganization 7bisavenuedelaPaixCasepostale2300 CH-1211Geneva2Switzerland UnitedNationsEnvironmentProgramme OzoneSecretariat P.O.Box30552Nairobi,00100Kenya USDepartmentofCommerce NationalOceanicandAtmosphericAdministration14thStreetandConstitutionAvenueNW HerbertC.HooverBuilding,Room5128Washington,D.C.20230 NationalAeronauticsandSpaceAdministration EarthScienceDivisionNASAHeadquarters300E.StreetSW Washington,D.C.20546-0001 EuropeanCommissionDirectorate-GeneralforResearchB-1049Bruxelles Belgium PublishedOctober2022.PostedonlineFebruary2023. ISBN:978-9914-733-97-6 Thisdocumentshouldbecitedas: WorldMeteorologicalOrganization(WMO).ScientificAssessmentofOzoneDepletion:2022,GAWReportNo.278,509pp.;WMO:Geneva,2022. Thisreportisavailableontheinternetatthefollowinglocations:https://ozone.unep.org/science/assessment/saphttps://www.csl.noaa.gov/assessments/ozone/2022 Note:Scientificfiguresfromthisreportareinthepublicdomainandmaybeusedwithoutpermission.Attributiontothisdocumentisencouraged. Thecoverofthisbookshowsanozonesondeballoonlaunchconductedin2018atSouthPole,Antarctica.PhotographbyJohannesWerthebach(IceCube/NSF).CoverdesignbyChelseaR.Thompson(NOAA). WorldMeteorologicalOrganization OzoneResearchandMonitoring–GAWReportNo.278 SCIENTIFICASSESSMENTOFOZONEDEPLETION 2022 WorldMeteorologicalOrganizationUnitedNationsEnvironmentProgramme NationalOceanicandAtmosphericAdministrationNationalAeronauticsandSpaceAdministrationEuropeanCommission SCIENTIFICASSESSMENTOFOZONEDEPLETION:2022 Co-ChairsoftheScientificAssessmentPanel (SAP)oftheMontrealProtocolandAssessmentCo-Chairs DavidW.FaheyPaulA.NewmanJohnA.PyleBonfilsSafari AssessmentScientificSteeringCommitteeDavidW.Fahey PaulA.NewmanJohnA.PyleBonfilsSafariJulieArblasterLucyCarpenterJianxinHu KenJucks DavidA.Plummer AssessmentCoordinatorSarahJ.Doherty GraphicsandLayoutCoordinatorChelseaR.Thompson ChapterLeadAuthors Chapter1:UpdateonOzone-DepletingSubstances(ODSs)andOtherGasesofInteresttotheMontrealProtocol Chapter2:Hydrofluorocarbons(HFCs) Chapter3:UpdateonGlobalOzone:Past, Present,andFuture Chapter4:PolarStratosphericOzone:Past, Present,andFuture Chapter5:StratosphericOzoneChangesandClimate Chapter6:StratosphericAerosolInjectionandItsPotentialEffectontheStratosphericOzoneLayer Chapter7:ScenariosandInformationforPolicymakers Annex:SummaryofAbundances,Lifetimes, ODPs,REs,GWPs,andGTPs JohannesC.LaubeSusannTegtmeier QingLiangMattRigby BirgitHasslerPaulJ.Young MartynP.ChipperfieldMichelleL.Santee HellaGarnyHarryHendon JamesHaywoodSimoneTilmes JohnS.DanielStefanReimann JamesB.BurkholderØivindHodnebrog Thefulllistofcontributorscanbefoundattheendofthisbook. REMEMBRANCES Itiswithsadnessthatwenotethepassingofthefollowingscientistswhohaveplayedimportantrolesintheinternationalscientificassessmentsoftheozonelayer. PAULJ.CRUTZEN (1933–2021)PaulJozefCrutzenwasborninAmsterdamon3December1933.Hisearlywork-inglifewasasacivilengineer.HisappointmentasacomputerprogrammerattheDepartmentofMeteorologyinwhatisnowStockholmUniversitywasthestartofhisatmosphericsciencecareer.HisPhDresearchestablishedtheimportantroleoftheoxidesofnitrogenintheformationanddestructionofozoneinthestratosphereandtroposphere.HisworkpointedtothepotentialdestructionofozoneiftheconcentrationofNOxradicals,keycomponentsincatalyticozonedestructioncycles,increasedfollowingenhancedemissionsfromaviation.ThiswaspartoftheworkforwhichPaulwasawardedthe1995NobelPrizeinChemistry,alongwithMarioMolinaandF.SherwoodRowland.Paul’scontributionswerewiderangingandhugelyinfluential.Theycoveredworkonpolarstratosphericclouds,thebudgetoftroposphericozone,‘nuclearwin-ter’,biomass-burning,cloudchemistry,climateandclimateintervention.HeworkedinBoulder,Colorado,duringthe1970satNOAAAeronomyLaboratoryandtheNationalCenterforAtmosphericResearch,beforemovingtobeheadoftheMaxPlanckInstituteforAtmosphericChemistryinMainzin1980.Ahighlightofhiscareerwasoriginatingandpromotingtheconceptofthe‘anthropocene’todescribethecurrentperiodwherehumanactivityishavingaprofoundinfluenceonourenvironment.Pauldiedon28January2021inMainz,Germany. MACKMCFARLAND (1947–2022)MackMcFarlandwasborninHouston,Texas,on9September1947.HereceivedhisBachelor’sDegreeinchemistryfromtheUniversityofTexas–AustinandaPhDinchemicalphysicsfromtheUniversityofColorado–Boulderin1973.Hecompletedpost-doctoralstudiesatYorkUniversityinCanadaandbecamearesearchscientistintheNOAAAeronomyLaboratoryinBoulder,Colorado.WhileatNOAA,Mackledinnovativemeasurementsofnitrogenoxides(NOx)onashipintheremotePacificOceanandintothemidstratosphereusingballoon-bornechemiluminescencedetectors.NOxchemistrycontrolsozoneamountsinthestratosphereandtroposphere.In1983,hejoinedDuPontCompanytohelpinterprettheemergingscientificin-formationandunderstandingofozonedepletionandclimatechange.MackwasinvolvedinmanyofthequadrennialscientificassessmentsofozonedepletionthatsupportdecisionmakingintheMontrealProtocolandincl