大氣氣溶膠大氣氣溶膠的重要性空氣質量人體健康能見度氣候變化云物理大氣輻射中小尺度動力系統(tǒng)（城市氣象）大氣化學AerosolsandClimateDirecteffectIndirecteffectScatteringFormationofCCNAerosolandVisibilityAerosolandVisibility氣溶膠的物理化學特征

化學成分空間分布物理特征氣溶膠的形成化學成分

SulfateNitrateBlackCarbonOrganicCarbon

POCandSOCMineralDustSea-salt垂直空間分布

SO2sulfateStratosphericBackgroundaerosolsOCS(1yearlifetime)StratosphereOCSSO2SO2SulfateBackgroundaerosols(1-2ug/m3)Volcanicaerosols(20-50ug/m3)對流層空間分布

對流層空間分布

物理特征

數(shù)濃度NucleationmodeAccumulationModeCoarseMode0.030.33um物理特征

質量濃度NucleationmodeAccumulationModeCoarseMode0.030.33Log-normaldistributionDiameterlnDm=lnDg+3N2σgwhere

Dm=massweighteddiameterDg=geometricmeandiameterDm>DgDgDm氣溶膠的形成SourcesofParticles:

IndustrialBiomassBurningSea-saltDust氣溶膠的形成氣溶膠的形成

ChemistryNucleationCondensationCoagulationHydrotropicgrowthDepositionAqueousChemistry

SO2H2SO4(1)Gas-phase(30-40%)SO2+OHH2SO4(2)Aqueous-phase(60-70%)SO2(a)+H2O2(a)H2SO4(a)SO2(a)+O3(a)H2SO4(a)

Nucleation

HomogeneousNucleationGasphaseParticlephaseHeterogeneousNucleationExistingsmallparticles(directemission)HomogeneousNucleationPhaseTransfer(GasParticles)GasvaporpressureP>PsPs=SaturationPressureSulfate,SOCProbleminHomogeneousNucleationTheoryNumberofparticleVaporPressure103TheoryMeasurementProgressontheproblem(1)Traditionaltheory

P>PsProgressontheproblem(1)NH3effects

P>PsProgressontheproblem(1)NH3effects(Psdecrease)

P>PsProgressontheproblem(1)OrganicAcideffects(Psdecrease)

P>PsZhangetal.,Science,2004Condensation

Ks,kdCoagulation

CoagulationM=Σ(i-1)Hydrotropicgrowth

Hydrotropicgrowth

DRH80Hydrotropicgrowth

Changethecross-sectionofscatteringHydrotropicgrowth

ChangetheabsorptionofaerosolsDeposition

DrydepositionWetdepositionDrydepositionTheflux(F)tothesurface

F=-VdxC

Vd=1/(Ra+Rb+Rc)Raistheaerodynamicresistance(meteorologicalconditions)Rbisthequasi-laminarsub-layerresistance(kineticviscosityofair)Rcisthetotalsurfaceresistance(surfacetype)Wetdeposition

RainfrequencyandstrengthSolubility(hydrophilicaerosolonly)氣溶膠－大氣化學

氣溶膠－大氣化學Photolysis(J)HeterogeneousreactionsTieetal.,JGR[2005]Aerosolsnotonlyaffectclimate,butalsochemistryPhotolysisrateJImportantPhotolysis(J)OzoneformationVOCs+OHRO2RO2+NONO2NO2+hvNO+O(J[NO2])

O+O2O3ImportantPhotolysis(J)OHformationO3+hv

O(1D)+O2(J[O3])O(1D)+H2O2OH

ImportantPhotolysis(J)OHformationCH2O+hv

H+HCO(J[CH2O])H+O2HO2HO2+NOOH+NO2ImportantPhotolysis(J)NOxinRemoteregionPAN+hv

NO2+Prod(J[PAN])

ImportantofPAN

TotransportNOxfromsourcetoremoteregion

PAN=CH3CO3NO2CH3CO3+NO2PANPAN+hvCH3CO3+NO2+CH3O2+NO3ImpactofaerosolonJ

J(i)=ΣFxσ(i)ψ(i)F=solarFluxImpactofaerosolsonJ

ScatteringF0F1ImpactofaerosolsonJ

AbsorbF0F1Aerosols

SulfateScatteringNitrateScatteringOCScattering(abs???)SOCScatteringSea-saltScatteringDustWeakabsorptionECStrongabsorptionAerosolParameters

Aerosolopticaldepth(AOD)Asymmetryparameter(g)Singlealbedo(ω)Aerosolopticaldepth

AsymmetryParameter

SingleAlbedo

MODISAOD

Factorstoaffecttheimpactof

AerosolsonradiativeforcingMassofaerosolconcentrations(AOD)Sizeofaerosols(AOD,g)Compositionofaerosols(AOD,ω)RH(AOD,ω,g)Shapeofaerosols(AOD,ω,g)TheverticaldistributionofaerosolVerticaldistributionof

scatteringaerosols

Verticaldistributionof

scatteringaerosols

Verticaldistributionof

absorptionaerosols

Verticaldistributionof

absorptionaerosols

ShapeofaerosolsCompositionofaerosols

EC(soot)ω=0.46

Sulfateω=1.0H2Oω=1.0ExternalMixingofaerosols

ā=ΣAixWiā=0.46*0.1+1.0*0.9=0.946ā=0.46*0.2+1.0*0.8=0.892Fineparticle~opticalproperties:

lightscatteringandabsorptionCollaborationwithMPIandIFT,GermanyGuangzhouurban,2004InternalMixingofAerosols

HeterogeneousReactions

ABwithγN2O5+sulfate2HNO3

N2O5+sulfate2HNO3

HO2+sulfateProducts

NOx,CO,HCs,AerosolsEmissions大氣化學－氣溶膠－模式NOx,CO,HCs,AerosolsMixingNightPBLMixinginlowPBLduringnightNOx,CO,HCs,AerosolsMixingDaytimePBLMixinginhighPBLduringdayNOx,CO,HC