Atmospheric ChemistryAtmospheric Chemistry
Atmospheric aerosol, air quality Atmospheric aerosol, air quality and climate: from the local to the and climate: from the local to the
global scale global scale
Sandro FuzziSandro Fuzzi
Institute of Atmospheric Sciences and ClimateInstitute of Atmospheric Sciences and ClimateNational Research CouncilNational Research Council
BolognaBologna
Atmospheric ChemistryAtmospheric Chemistry
The atmosphere: a multiphase systemThe atmosphere: a multiphase system
The atmosphere is a multiphase system, The atmosphere is a multiphase system, insofar as all three phases are insofar as all three phases are simultaneously present: gas, solid, liquidsimultaneously present: gas, solid, liquid
Dry aerosol constitutes the solid phaseDry aerosol constitutes the solid phase Wet aerosol and cloud/fog droplets Wet aerosol and cloud/fog droplets
constitute the liquid phaseconstitute the liquid phase
Atmospheric ChemistryAtmospheric Chemistry
Aerosol: definitionAerosol: definition
““a stable suspension of solid and/or a stable suspension of solid and/or liquid in air”liquid in air”
Size interval Size interval
0.003 - 100 0.003 - 100 mm
Atmospheric ChemistryAtmospheric Chemistry
Aerosol mass and number Aerosol mass and number concentrationsconcentrations
Aerosol type
Aerosol number
(N/cm3)
Aerosol mass
(g/m3)
Plume
107
102-105
Urban area 105-106 100-1000 Rural area 103-105 10-100 Remote area 100-500 10 Artic 10-1000 0.1-10 Anctartica 10-100 0.1
Atmospheric ChemistryAtmospheric Chemistry
emission deposition
transport - transformation
surface
atmosphere
Cycle of atmospheric aerosolCycle of atmospheric aerosol
Atmospheric ChemistryAtmospheric Chemistry
Emission of aerosol in the atmosphereEmission of aerosol in the atmosphere
Fragmentation processesFragmentation processes(primary aerosol, mostly super-micron size)(primary aerosol, mostly super-micron size)
Combustion processesCombustion processes(primary aerosol, wide size range)(primary aerosol, wide size range)
Conversion processesConversion processes(secondary aerosol, sub-micron size)(secondary aerosol, sub-micron size)
Atmospheric ChemistryAtmospheric Chemistry
Global aerosol sources (Tg/yr)Global aerosol sources (Tg/yr)
NaturalNatural 30603060PrimaryPrimary Soil mobilization 1500 Soil mobilization 1500 Sea salt 1300Sea salt 1300
Volcanic aerosol 30Volcanic aerosol 30 Biological particles 50Biological particles 50Secondary Secondary Sulphate (conv. SO Sulphate (conv. SO22) 100) 100
Nitrate (conv. NONitrate (conv. NOXX) 20) 20 Organic aerosol (conv. BVOC) 60Organic aerosol (conv. BVOC) 60
AnthropogenicAnthropogenic 395395 PrimaryPrimary Industrial aerosol 100 Industrial aerosol 100 Fossil fuel combustion 25Fossil fuel combustion 25 Biomass burning 80Biomass burning 80SecondarySecondary Sulphate (conv. SO Sulphate (conv. SO22) 140) 140
Nitrate (conv. NONitrate (conv. NOXX) 40) 40 Organic aerosol (conv. AVOC) 10Organic aerosol (conv. AVOC) 10
Atmospheric ChemistryAtmospheric Chemistry
Aerosol optical thicknessAerosol optical thicknessModerate Resolution Imaging Spectroradiometer (MODIS) Moderate Resolution Imaging Spectroradiometer (MODIS)
on NASA Terra satelliteon NASA Terra satellite
Jan.
Feb.Feb.
Mar
AprApr
July
Aug.
May
Sept.
AOT monthly averageyear 2001
AOT < 0.1remote atmosphere
AOT > 0.2polluted atmosphere
Atmospheric ChemistryAtmospheric Chemistry
Aerosol optical thicknessAerosol optical thickness(June-August 2001)(June-August 2001)
0.1 0.2 0.3 0.4
ISAC-CNR - ROMA
Atmospheric ChemistryAtmospheric Chemistry
Saharan dust plume (2 March 2002)Saharan dust plume (2 March 2002)SeaWIFFSSeaWIFFS satellitesatellite
dust
pollutionaerosol
Atmospheric ChemistryAtmospheric Chemistry
Gas-to-particle-conversionGas-to-particle-conversion
Two or more gaseous species react Two or more gaseous species react producing a low vapor pressure producing a low vapor pressure compoundcompound
The new compound can:The new compound can:condense onto a pre-existing particlecondense onto a pre-existing particlenucleate forming a new ultra-fine particlenucleate forming a new ultra-fine particle
Atmospheric ChemistryAtmospheric Chemistry
NucleationNucleation
Evidence of formation of “new” particles of a few Evidence of formation of “new” particles of a few nm size reported by Aitken already in 1897nm size reported by Aitken already in 1897
Measurements possible only in the last few years Measurements possible only in the last few years (DMPS)(DMPS)
Mechanisms proposed:Mechanisms proposed:binary nucleation (Hbinary nucleation (H22O-HO-H22SOSO44))
ternary nucleation (Hternary nucleation (H22O-HO-H22SOSO44-NH-NH33))
ion induced nucleationion induced nucleation
Atmospheric ChemistryAtmospheric Chemistry
Formation and growth of ultra-fine Formation and growth of ultra-fine particles (Po Valley)particles (Po Valley)
00:00 10:30 13:30 18:00 24:00
Laaksonen et al., Geophys. Res. Lett., 2005
Atmospheric ChemistryAtmospheric Chemistry
Frequency of nucleation in the Po ValleyFrequency of nucleation in the Po Valley
Event days (Classes (1+2+3)) / All days
0.00 %
10.00 %
20.00 %
30.00 %
40.00 %
50.00 %
60.00 %
70.00 %
Jan Feb Mar Apr May June July Aug Sep Oct Nov Dec
Months
Fre
quen
cy%
Atmospheric ChemistryAtmospheric Chemistry
Gas/particle connectionGas/particle connection
0 25 500
25
50
-20
-15
-10
-505101520
VOC reduction %
NO
x re
duct
ion
%
PM 2.5
15-20
10-15
5-10
0-5
-5-0
-10- -5
-15- -10-20- -15
Meng et al., Science, 1997
Atmospheric ChemistryAtmospheric Chemistry
Aerosol removalAerosol removal
Two series of mechanisms are responsible Two series of mechanisms are responsible for aerosol removal:for aerosol removal:
dry removal dry removal (sedimentation, turbulence, (sedimentation, turbulence, impact)impact)
wet removal wet removal (incorporation in clouds and (incorporation in clouds and deposition through precipitation)deposition through precipitation)
Atmospheric ChemistryAtmospheric Chemistry
diameter (micrometers)
day
s
0.001
0.01
0.1
1
10
100
0.001 0.01 0.1 1 10 1000.1
1
10
100
1000
hou
rs
Brownian diffusioncoagulation sedimentation
accumulation mode
Aerosol residence timeAerosol residence time
Atmospheric ChemistryAtmospheric Chemistry
Aerosol chemical compositionAerosol chemical composition
Unlike atmospheric gases, aerosols cannot be characterised by a single parameter such as concentration. Instead atmospheric aerosols are characterised by their physical, chemical and optical properties, as well as their state of mixture (internal or external) and phase (solid, liquid or ice).
Atmospheric ChemistryAtmospheric Chemistry
Aerosol complexityAerosol complexity Various chemical species (elemental, organic
and inorganic) are present Solid, liquid and ice particles from a few
nanometers to a few hundred micrometers are present
Internally/externally mixed system exists Temporal (diurnal, seasonal and annual), and
spatial (long/lat and altitude) variability and systematic relationships need to be considered
Atmospheric ChemistryAtmospheric Chemistry
Carbonaceous aerosolCarbonaceous aerosol
Until recently, only the inorganic Until recently, only the inorganic fraction of the aerosol was knownfraction of the aerosol was known
Now we know that carbonaceous Now we know that carbonaceous aerosols are ubiquitous and can aerosols are ubiquitous and can contribute from 20% to > 80% of the contribute from 20% to > 80% of the mass of fine aerosolmass of fine aerosol
Atmospheric ChemistryAtmospheric Chemistry
Forms of carbon in the aerosolForms of carbon in the aerosol
black carbon (BC)black carbon (BC) organic carbon (OC)organic carbon (OC)
total carbon (TC) = BC + OCtotal carbon (TC) = BC + OC
Atmospheric ChemistryAtmospheric Chemistry
Composition of fine aerosolComposition of fine aerosol
polluted continental areapolluted continental area40 40 g/mg/m33
biomass burningbiomass burning60 60 g/mg/m33
remote forested arearemote forested area3 3 g/mg/m33
remote marine arearemote marine area1 1 g/mg/m33
polluted marine areapolluted marine area6 6 g/mg/m33
OCOCBCBCinorganicinorganic
Atmospheric ChemistryAtmospheric Chemistry
Sources of fine organic aerosol Sources of fine organic aerosol
PrimaryPrimarybiomass burningbiomass burningfossil fuelfossil fuelbiological material biological material (?)(?)
SecondarySecondaryanthropogenic VOC oxidationanthropogenic VOC oxidationbiogenic VOC oxidationbiogenic VOC oxidation
Atmospheric ChemistryAtmospheric Chemistry
Global emissions of fine organic Global emissions of fine organic aerosol (Tg/y)aerosol (Tg/y)
Source E. North E. South Global biomass 28 26 54 (45-80) fossil fuel 28 0.4 28 (10-30) BVOC 8.2 7.4 16 (8-40) AVOC 0.45 0.15 0.6 (0.3-1.8) Tot. organic 64 34 98 (60-150) Tot. aerosol 600 200 800
Atmospheric ChemistryAtmospheric Chemistry
Size-segregated aerosol chemical Size-segregated aerosol chemical compositioncomposition
Bologna - winter
D(m)
0.05 0.14 0.42 1.2 3.5 10
Ma
ss fractio
n (%
) 0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
mass(
g/m3)
0
5
10
15
20
25
30
35
INS WSOC WS_INORG
Cheju Island
D(m)
0 0.2 0.5 1.5 5.5 10
Mass fractio
n (%) 0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
mass(
g/m3)
3
4
5
6
7
8INS WSOC WS_INORG MINATROC
D(m)
0.05 0.14 0.42 1.2 3.5 10
Mass fraction (%
) 0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
mass(
g/m3)
0
2
4
6
8
10
INS WSOC WS_INORG
Hyytiala - QUESTNo nucleation events in boreal forest
D(m)
0.05 0.14 0.42 1.2 3.5 10
Mass fra
ction (%) 0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
ma
ss(g/m
3)
0
1
2
3
4
5
6
7
8
INS WSOC WS_INORG
Rondonia - SMOCCDry period
D(m)
0.05 0.14 0.42 1.2 3.5 10
Mass fraction (%
) 0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
mass(
g/m3)
0
5
10
15
20
25
30
35
40
INS WSOC WS_INORG
Mace HeadBloom period
D(m)
0.06 0.125 0.25 0.5 1 2 4 8 16
Mass fractio
n (%) 0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
mass(
g/m3)
0
1
2
3
4
5
6
INS WSOC WS_INORG
Continental polluted (Po Valley) Polluted site in Asia (Korea) Saharan dust (Mt. Cimone)
Finnish boreal forest Biomass burning in Amazzonia Marine remote site (Mace Head)
Atmospheric ChemistryAtmospheric Chemistry
0
20
40
60
80
100
120
Jun
gfr
au
joch
(C
H)
Se
vett
ijarv
i (F
IN)
Skr
ea
da
len
(N
)
Bir
ken
es
(N)
Asp
vre
ten
(S
)
Ch
au
mo
nt
(CH
)
Mo
na
gre
ga
(E
)
Illm
itz (
A)
Ha
rwe
ll (G
B)
Ho
he
np
eis
sen
be
rg (
D)
Me
lpitz
(D
)
Isp
ra (
I)
Wa
asm
un
ste
r (B
)
Zu
eri
ch (
CH
)
Ba
sel (
CH
)
Lo
nd
on
-B (
GB
)
Le
ipzi
g 9
7-9
9 (
D)
Ge
nt
(B)
Bo
log
na
(I)
Ba
rce
lon
a (
E)
Be
rn (
CH
)
Lo
nd
on
-M (
GB
)
Wie
n (
A)
PM
10 (
µg/
m³)
average
median
EU 24-hr limit value
2005 EU annual standard
2010 EU annual standard
0
20
40
60
80
100
120
Jun
gfr
au
joch
(C
H)
Se
vett
ijarv
i (F
IN)
Skr
ea
da
len
(N
)
Bir
ken
es
(N)
Asp
vre
ten
(S
)
Ch
au
mo
nt
(CH
)
Mo
na
gre
ga
(E
)
Illm
itz (
A)
Ha
rwe
ll (G
B)
Ho
he
np
eis
sen
be
rg (
D)
Me
lpitz
(D
)
Isp
ra (
I)
Wa
asm
un
ste
r (B
)
Zu
eri
ch (
CH
)
Ba
sel (
CH
)
Lo
nd
on
-B (
GB
)
Le
ipzi
g 9
7-9
9 (
D)
Ge
nt
(B)
Bo
log
na
(I)
Ba
rce
lon
a (
E)
Be
rn (
CH
)
Lo
nd
on
-M (
GB
)
Wie
n (
A)
PM
2.5
(µg/
m³)
average
median
USA annual standard
Compliance with Compliance with air quality air quality standardsstandards
Atmospheric ChemistryAtmospheric Chemistry
y = 0.57x
y = 0.85x
0
10
20
30
40
50
60
70
80
90
100
110
120
0 10 20 30 40 50 60 70 80 90 100 110 120
PM 10 (µg/m³)
PM
2.5
(µ
g/m
³)
Sevettijarvi (FIN)
Skreadalen (N)
Birkenes (N)
Chaumont (CH)
Waasmunster (B)
Gent (B)
Bologna (I)
Zuerich (CH)
Basel (CH)
Barcelona (E)
Bern (CH)
0%
20%
40%
60%
80%
100%
Se
vettija
rvi (
FIN
)
Skr
ea
da
len
(N
)
Bir
ken
es
(N)
Pu
y d
e D
om
e (
F)
Ch
au
mo
nt (C
H)
Mo
na
gre
ga
(E
)
Wa
asm
un
ste
r (B
)
Me
lpitz
96
-99
(G
)
Isp
ra (
I)
Zu
eri
ch (
CH
)
Ba
sel (
CH
)
Ge
nt (
B)
Bo
log
na
(I)
Ba
rce
lon
a (
E)
Be
rn (
CH
)
PMPM1010 vs. PM vs. PM2.52.5
Atmospheric ChemistryAtmospheric Chemistry
Aerosol size-segregated chemistryAerosol size-segregated chemistry
0
2
4
6
8
10
12
14
16
18
0.05-0.09 0.09-0.16 0.16-0.30 0.30-0.60 0.60-1.0 1.0-1.8 1.8-3.1 3.1-6.2 6.2-9.9
aerodynamic diameter (µm)
dM
/dL
og
Dp
(µ
g/m
³)
BC
OM
unacc.
NH4
nssSO4
sea salt
min. dust
Gent, Belgium
Marseille, France
Atmospheric ChemistryAtmospheric Chemistry
Aerosol environmental effectsAerosol environmental effects
human healthhuman health vegetation and materialsvegetation and materials visibilityvisibility climateclimate hydrological cyclehydrological cycle
Atmospheric ChemistryAtmospheric Chemistry
Effects on human healthEffects on human health
Mechanisms by which ihalable atmospheric Mechanisms by which ihalable atmospheric particles affect human health are still poorly particles affect human health are still poorly known. Two types of interactions can however be known. Two types of interactions can however be identified:identified: mechanicalmechanical: : inflammation ofinflammation of tissues or receptors tissues or receptors
chemicalchemical: : inflammation ofinflammation of tissues or receptors, tissues or receptors, damages of cellular tissues, mutagenesis of cellsdamages of cellular tissues, mutagenesis of cells
COST action 633: Particulate matter: Properties relatedCOST action 633: Particulate matter: Properties relatedto health effectsto health effects http://cost.cordis.lu/src/action_detail.cfm?action=633http://cost.cordis.lu/src/action_detail.cfm?action=633
Atmospheric ChemistryAtmospheric Chemistry
Effects on vegetationEffects on vegetationand materialsand materials
Are mainly due to chemical reactions of Are mainly due to chemical reactions of particulate matter deposited on the surfaces particulate matter deposited on the surfaces activated by water (dew, fog, precipitation)activated by water (dew, fog, precipitation)
The reaction products in solution can then The reaction products in solution can then produce damages to materials and produce damages to materials and vegetation tissues vegetation tissues
Atmospheric ChemistryAtmospheric Chemistry
Damage to materialsDamage to materialsPortal figure of Herten Castle, Germany (1702)Portal figure of Herten Castle, Germany (1702)
1908 1968
Atmospheric ChemistryAtmospheric Chemistry
1
10
100
1000
1 10 100 1000
Concentration (µg/m3)
Vis
ibil
ity
(km
)
range of actualconcentrations
of aerosol inthe atmosphere
Effect on visibilityEffect on visibility
Atmospheric ChemistryAtmospheric Chemistry
Visibility on a Visibility on a clear and a hazy clear and a hazy
dayday
Denver, Colorado
Atmospheric ChemistryAtmospheric Chemistry
Aerosol-climateAerosol-climate The atmospheric aerosol The atmospheric aerosol
influences the Earth’s influences the Earth’s climate in two ways:climate in two ways:
direct effectdirect effect: reflecting : reflecting the incoming solar the incoming solar radiation back to space;radiation back to space;
indirect effectindirect effect: acts as : acts as CCN favoring formation CCN favoring formation of clouds which can also of clouds which can also reflect solar radiation back reflect solar radiation back to space . to space .
Both these mechanisms Both these mechanisms exert a cooling effect on exert a cooling effect on climateclimateaerosol sources
Atmospheric ChemistryAtmospheric Chemistry
0 5 10 15 20 25 30 35
-30
-20
-10
0
10
20
reff
T [
oC
]
m]
Thai pre-mons
Israel dust
Australia urbanINDOEX polluted
Amazon smoke
Suppression of precipitationSuppression of precipitation
highconcentration
of aerosol
low concentrationof aerosol
thresholdfor productionof precipitation
Ramanathan et al.,Science, 2001
Visible and InfraRed Sensor (VIRS)Satellite NASA-Tropical Rainfall Measuring Mission (TRMM)
Atmospheric ChemistryAtmospheric Chemistry
Microstructure of cloudsMicrostructure of clouds
NOAA –AVHRR satellitered = larger dropletsyellow = smaller droplets
South AustraliaPort Augusta power plant
Port Pirie lead smelter
Adelaide port
oil refineries
Rosenfeld, Science, 2000
Atmospheric ChemistryAtmospheric Chemistry
Review on aerosols in EuropeReview on aerosols in EuropeA European Aerosol Phenomenology. 1: physical characteristics of particulate A European Aerosol Phenomenology. 1: physical characteristics of particulate
matter at kerbside, urban, rural and background sites in Europematter at kerbside, urban, rural and background sites in EuropeVan Dingenen, R., F. Raes, J.-P. Putaud, U. Baltensperger, E. Brüggemann, A. Charron, Van Dingenen, R., F. Raes, J.-P. Putaud, U. Baltensperger, E. Brüggemann, A. Charron, M.C. Facchini, S. Decesari, S. Fuzzi, R. Gehrig, H.-C. Hansson, R.M. Harrison, C. M.C. Facchini, S. Decesari, S. Fuzzi, R. Gehrig, H.-C. Hansson, R.M. Harrison, C. Hüglin, A.M. Jones, P. Laj, G. Lorbeer, W. Maenhaut, F. Palmgren, X. Querol, S. Hüglin, A.M. Jones, P. Laj, G. Lorbeer, W. Maenhaut, F. Palmgren, X. Querol, S. Rodriguez, J. Schneider, H.Rodriguez, J. Schneider, H.ten Brink, P. Tunved, K. Tørseth, B. Wehner, E. ten Brink, P. Tunved, K. Tørseth, B. Wehner, E. Weingartner, A. Wiedensohler and P. WåhlinWeingartner, A. Wiedensohler and P. Wåhlin
Atmos. Environ., 38, 2561-2577 (2004)Atmos. Environ., 38, 2561-2577 (2004)
A European Aerosol Phenomenology. 2: chemical characteristics of particulate A European Aerosol Phenomenology. 2: chemical characteristics of particulate matter at kerbside, urban, rural and background sites in Europematter at kerbside, urban, rural and background sites in EuropePutaud, J.-P., F. Raes, R. Van Dingenen J.-P. U. Baltensperger, E. Brüggemann, M.C. Putaud, J.-P., F. Raes, R. Van Dingenen J.-P. U. Baltensperger, E. Brüggemann, M.C. Facchini, S. Decesari, S. Fuzzi, R. Gehrig, H.-C. Hansson, C. Hüglin, P. Laj, G. Lorbeer, Facchini, S. Decesari, S. Fuzzi, R. Gehrig, H.-C. Hansson, C. Hüglin, P. Laj, G. Lorbeer, W. Maenhaut, N. Mihalopoulos, K. Müller, X. Querol, S. Rodriguez, J. Schneider, G. W. Maenhaut, N. Mihalopoulos, K. Müller, X. Querol, S. Rodriguez, J. Schneider, G. Spindler, H.Spindler, H.ten Brink, K. Tørseth, B. Wehner and A. Wiedensohlerten Brink, K. Tørseth, B. Wehner and A. Wiedensohler
Atmos. Environ., 38, 2579-2595 (2004)Atmos. Environ., 38, 2579-2595 (2004)
Atmospheric ChemistryAtmospheric Chemistry
Reviews on organic aerosolReviews on organic aerosol
Organic aerosol and global climate modelling: A reviewOrganic aerosol and global climate modelling: A review
Kanakidou, M., J. H. Seinfeld, S. N. Pandis, I. Barnes, F. J. Dentener, M. Kanakidou, M., J. H. Seinfeld, S. N. Pandis, I. Barnes, F. J. Dentener, M. C. Facchini, R. van Dingenen, B. Ervens, A. Nenes, C. J. Nielsen, E. C. Facchini, R. van Dingenen, B. Ervens, A. Nenes, C. J. Nielsen, E. Swietlicki, J.P. Putaud, Y. Balkanski, S. Fuzzi, J. Hjorth, G. K. Moortgat, Swietlicki, J.P. Putaud, Y. Balkanski, S. Fuzzi, J. Hjorth, G. K. Moortgat, R. Winterhalter, C. E. L. Myhre, K. Tsigaridis, E. Vignati, E. G. R. Winterhalter, C. E. L. Myhre, K. Tsigaridis, E. Vignati, E. G. Stephanou, J. WilsonStephanou, J. Wilson
Atmos. Chem. Phys., 5, 1053-1123 (2005)Atmos. Chem. Phys., 5, 1053-1123 (2005)
A critical assessment of the current state of knowledge and research A critical assessment of the current state of knowledge and research needs on the role of organic aerosols in the atmosphere, climate, needs on the role of organic aerosols in the atmosphere, climate, and global changeand global changeFuzzi, S., M.O. Andreae, B. Huebert, M. Kulmala, Fuzzi, S., M.O. Andreae, B. Huebert, M. Kulmala, T. Bond, M. Boy, S.J. T. Bond, M. Boy, S.J. Doherty, A. Guenther, M. Kanakidou, K. Kawamura, V.-M. Kerminen, U. Doherty, A. Guenther, M. Kanakidou, K. Kawamura, V.-M. Kerminen, U. Lohmann, U. Pöschl, L.M. RussellLohmann, U. Pöschl, L.M. RussellAtmos. Chem. Phys., 6, 2017-2038 (2006)Atmos. Chem. Phys., 6, 2017-2038 (2006)