Advances in Measurements of tropospheric

H h C

aerosols

Hugh Coe

Rami Alfarra James Allan Keith Bower Mike Flynn GordonRami Alfarra, James Allan, Keith Bower, Mike Flynn, Gordon McFiggans, Dantong Liu, Will Morgan, Jonny Taylor, Paul Williams

Gavin McMeeking – CSU Jacqui Hamilton – York

Doug Worsnop – Aerodyne Jose Jimenez – UC Boulder

Qi Zhang – UC Davis Markus Petters – N Carolina

Aerosol particle properties and tprocesses – a measurement

perspective

Outline

p p

• Background

• Organic aerosol – aerosol mass spectrometry

• Black carbon single particle soot photometry• Black carbon – single particle soot photometry

• cloud condensation nuclei

Effects of Atmospheric AerosolsREACTIONS (Secondary PM)REACTIONS (Secondary PM)REACTIONS (Secondary PM)Indirect effect

on climate

REACTIONS (Secondary PM)Indirect effect

on climate

REACTIONS (Secondary PM)Indirect effect

on climate

Direct effect li

on climate

Direct effect li

on climate

Direct effect li

on climate

Heterogeneous

A l (PM)A l (PM)A l (PM)

on climate

Cloud condensation A l (PM)

on climate

Cloud condensation A l (PM)

on climate

Cloud condensation

Heterogeneous reactions

Aerosols (PM)

Visibility

Aerosols (PM)

Visibility Health

Aerosols (PM)

Visibility Health

condensation nuclei

Aerosols (PM)

Visibility HealthAcid rain

condensation nuclei

Aerosols (PM)

Visibility HealthAcid rain

condensation nuclei

EMISSIONS (P i PM)

Visibility reduction

EMISSIONS (P i PM)

Visibility reduction

Health effect

EMISSIONS (P i PM)

Visibility reduction

Health effect

EMISSIONS (P i PM)

Visibility reduction

Health effectDeposition

EMISSIONS (P i PM)

Visibility reduction

Health effectDeposition

EMISSIONS (Primary PM)EMISSIONS (Primary PM)EMISSIONS (Primary PM)EMISSIONS (Primary PM)EMISSIONS (Primary PM)

What do field measurements tell us?

Id tif• Identify new processes

• Quantify properties and variations of propertiesQuantify properties and variations of properties

• Provide an important sanity check for model predictions

• Provide test cases against which process descriptions can b t t dbe tested

• Establish long term data sets to test larger scale models

Focus of this talk – quantifying key processes and ti i th lif l f l

Long range Long range transport in transport in Long range Long range transport in transport in

properties in the lifecycle of aerosol

IndirectIndirect

pthe FTthe FT

Transport Transport into FTinto FT

FT FT NucleationNucleationIndirectIndirect

pthe FTthe FT

Transport Transport into FTinto FT

FT FT NucleationNucleation

Transport andTransport and

Modification Modification to CCNto CCN

Changing Changing precipitation precipitation

Direct Direct EffectEffect

Indirect Indirect EffectEffect

NucleationNucleation

Transport andTransport and

Modification Modification to CCNto CCN

Changing Changing precipitation precipitation

Direct Direct EffectEffect

Indirect Indirect EffectEffect

NucleationNucleation

Urban air Urban air Urban air Urban air

Dry andDry andTransport and Transport and chemical chemical transformationtransformation

Wet Wet DepositionDeposition

ratesrates

BL NucleationBL Nucleation

Dry andDry andTransport and Transport and chemical chemical transformationtransformation

Wet Wet DepositionDeposition

ratesrates

BL NucleationBL Nucleation

pollutionpollutionpollutionpollution

Marine & Marine & ti t lti t l

Marine & Marine & ti t lti t l

Biogenic, Biogenic, anthropogenic &anthropogenic &Biogenic, Biogenic, anthropogenic &anthropogenic &continental continental

background inputbackground inputcontinental continental background inputbackground input

anthropogenic & anthropogenic & volcanic gasesvolcanic gasesanthropogenic & anthropogenic & volcanic gasesvolcanic gases

Field measurement platforms

Development of the Quadrupole Aerosol Mass Spectrometer

Aerodyne Aerosol Mass Spectrometer

The Ubiquity of Organic Aerosol

Zhang et al., 2007

Understanding the organic aerosol fraction100

Diesel FuelA 43 57 100 4418

100

50

0

Diesel Fuel Laboratory

A

29

43

43

55

57

7169 85

97

100

50

0Jeju Island

Fulvic Acid Laboratory

44

44

4355

18

18

27

A

B100

50

0%)

Lubricating Oil Laboratory

B

29

43

43 55 57

7169

83 97

100

50

0

Jeju Island Marine

Jungfraujoch44

4355

18

B

C100

50

0elat

ive

Inte

nsity

(% Disel Exhaust Aerosol New York, USA

C

1527

4341 55 57

7169

8397 109

50

0

e In

tens

ity (%

)

100LangleyRural

g j High Alpine

4443

43

55

18

27

29

D0

Re

100

50

0

Traffic Dominated Urban Aerosol Vancouver, Canada

D

18 29

43

44

5557

7169

83 9791

Rel

ativ

e

50

0100

50

Rural

Vancouver Oxidised Urban

4443

55

18

5569 91

27

E

0100

50

E Traffic Dominated Urban Aerosol Manchester, UK

18 27

43

44

55 57

716983

9197

100

50

50

0

Vancouver Urban Traffic18 2927

4143

4455

5769

5557 69 91

F

14012010080604020m/z

0

100908070605040302010m/z

50

0

6967 8183 91

Alfarra, PhD thesis, 2004

Understanding the organic aerosol fraction

Ulbrich et al., ACP 2009

Classification of PMF factors

Urban downwind Urban

Rural background 1. Oxygenated Organic Aerosol (OOA): strong peak at m/z 44(OOA): strong peak at m/z 44

2. Hydrocarbon-like Organic Aerosol (HOA): large peak at m/z 43 and 57(HOA): large peak at m/z 43 and 57

3. Solid Fuel Organic Aerosol (SFOA): a notable signal at m/z 60, a(SFOA): a notable signal at m/z 60, a typical indicator of levoglucosan.

Urban downwind: Holme Moss

Liu, D., Allan, J., Corris, B., Flynn, M., Andrews, E., Ogren, J., Beswick, K., Bower, K., Burgess, R., Choularton, T.,y g gDorsey, J., Morgan, W., Williams, P. I., and Coe, H.: Carbonaceous aerosols contributed by traffic and solid fuel burning ata polluted rural site in Northwestern England, Atmos. Chem. Phys., 11, 1603-1619, doi:10.5194/acp-11-1603-2011, 2011.

Winter time urbanWinter-time urban Measurements in London and Manchester

traffic cooking andtraffic, cooking and solid fuel emissions represent 40%, 34% p ,and 26% respectively of the primary organic

l d i thaerosol during the study periods.

Transformation on a regional scale

Transformation on a regional scale

Organic Aerosol Components Worldwide

Jimenez, Canagaratna, Donahue, et al., Science 326, 1525 (2009)

SOA Measurements vs. Models (II)Increase in SOA with residence time in atmosphere ( )

DeGouw et al.Heald et al.

Johnsonet al.

atmosphere

Volkamer, Jimenez, et

Much higher SOA than predicted with current modelsDi t i ith ti

Volkamer, Jimenez, et al., GRL, 2006.

Discrepancy appears to increase with time

2D Basis Set: Volatility and O/C

Jimenez, Canagaratna, Donahue, et al., Science 326, 1525 (2009)

The volatility basis set approach represents measurements reasonably well but there are lots of untested assumptionsreasonably well but there are lots of untested assumptions

Organic Aerosol Components Worldwide

Jimenez, Canagaratna, Donahue, et al., Science 326, 1525 (2009)

BLACK CARBON MEASUREMENTS

•Need to establish the Black Carbon burden and distribution in the atmospherethe atmosphere

• Need to understand BC mixing state

• The mixing state of black carbon controls:

- Its optical propertiesp p p

- Its ability to be involved

i l d ti tiin cloud activation

- Its wet removal and

hence lifetime in the

atmosphereatmosphere

From Bond et al 2006

DMT Single Particle Soot Photometer (SP2)

Schwarz, J. P., Gao, R. S., Fahey, D. W., Thomson, D. S., Watts, L. A., Wilson, J. C., Reeves, J. M., Baumgardner, D. G., Kok, G. L., Chung, Schulz, S. M., Hendricks, J., Lauer, A., K¨archer, B., Slowik, J. G., Rosenlof, K. H., Thompson, T. L., Langford, A. O., Lowenstein, M., and Aikin, K. C.: Single-particle measurements of midlatitude black carbon and light-scattering aerosols from the boundary layer to the lower stratosphere, J. Geophys. Res., 111, D16207,y y p , p y , , ,doi:10.1029/2006JD007076, 2006.

E l f SP2 tExample of raw SP2 measurement

Incandescence high gainLeading edge scatter fitg g

Scatter (TEAPD)

Scatter

Scatter (TEAPD)

How do we obtain BC mixing state information?information?

Time delay

from Subramanian et al. (2009) “thickly coated”“thinly coated”

Holme Moss – downwind urban UK BC

• Using AMS PMF we have been able to quantify contributions to primary organic aerosol from traffic

d lid f l b iand solid fuel burning• The addition of solid fuel

derived aerosol in the evening greatly enhances absorptiongreatly enhances absorption and decreases the SSA

• A bilinear fit of the HOA and SFOA to the rBC time seriesSFOA to the rBC time series was used to attribute the contribution of the different sources to the total rBCsources to the total rBC.

• Emission factors of 1.61 μgHOA/μgC and 1.96 μgSFOA/μgC were derived for μgS O /μgC e e de ed otraffic emission and solid fuel burning respectively

Vertical structure: BC massVertical structure: BC massNORTH AMERICA mid‐latitudeUK

ADIENT 2008 mean profile

6)t a

l. (2006

chwarz e

tSc

Thinly coated

signa

BC BC mixing efficiency=thickly coated BC/total BC

al

Elapsed timeThickly coated BC

signal

Liu, D., Flynn, M., Gysel, M., Targino, A., Crawford, I., Bower, K., Choularton, T., Jurányi, Z., Steinbacher, M., Hüglin, C., Curtius, J., Kampus, M., Petzold, A., Weingartner, E., Baltensperger, U., and Coe, H.: Single particle characterization of black carbon aerosols at a tropospheric alpine site in

Elapsed time

Coe, H.: Single particle characterization of black carbon aerosols at a tropospheric alpine site in Switzerland, Atmos. Chem. Phys., 10, 7389-7407, doi:10.5194/acp-10-7389-2010, 2010.

Combining measurements of hygroscopic properties and BChygroscopic properties and BC

Combining measurements of hygroscopic properties and BChygroscopic properties and BC

• Observed number fraction of BC that is CCN active at 0.2 % supersaturation is generally low in an urban area near sources and varies with airmass.

• Method can be combined with measures of air parcel physical and photochemical age to provide quantitative estimates for characterizing hydrophobic-to-hydrophilic conversion rates

SUMMARYSUMMARY• Recent measurements of organic aerosol have delivered

new insight into organic aerosol ubiquity and abundance• Novel mass spectrometric methods are being rapidly

developed to probe organic complexity and quantify organic processing in the atmosphereorganic processing in the atmosphere

• Measurements of black carbon on a particle by particle basis are delivering new information on its sizebasis are delivering new information on its size distribution and behaviour in the atmosphere

• Rapid advances in mass spectrometric and optical methods are rapidly increasing our ability to quantify key aerosol properties in the atmosphereaerosol properties in the atmosphere

Measurement Platforms2. How we measured aerosol in Borneo

BIOGENIC ORGANIC AEROSOLTh OP3 P j i BMeasurement PlatformsThe OP3 Project in Borneo:

The plane from the towere p a e o t e to e

The tower from the plane

Identification of the 82 peak5. Organic AnalysisPointer to the first detected molecular marker 

d f i id i hIdentification of the 82 peakcompound of isoprene oxidation that comprises a significant fraction of biogenic SOA

Org SO4

34SO3

H33SO3

C5H6O4

NH4 NO3

3

C6H10

12010080604020

Chl

12010080604020m/z 82.182.081.9

Can identify the fragment using the hi‐res ToF‐AMS

Identification of the 82 peak5. Organic AnalysisPMF can identify the proportions of components

Identification of the 82 peak

Identification of the 82 peak5. Organic AnalysisIdentification of Methyl Furan as key 

82Identification of the 82 peakcomponent at mz 82

GC x GC analysis IDs C5H6O+ as methyl furan

3MF has been shown to3MF has been shown to come from isoprene oxidation (Atkinson et al., ( ,1989)BUT MF too volatile to be in particle phase –Implies product formed during vaporizationduring vaporization

Identification of the 82 peak5. Organic Analysis

• Correlation with isoprene products• Enhancements in afternoon throughIdentification of the 82 peakEnhancements in afternoon through 

boundary layer• Subsequent identification at other low 

NOx, high isoprene sites

Identification of the 82 peak5. Organic AnalysisSUMMARY OF FINDINGS

Identification of the 82 peak• Methyl Furan identified in ambient samples during low 

NOx‐high isoprene conditionsNOx high isoprene conditions• Likely MF is produced during measurement through 

volatilisation • Precursor requires laboratory identification• Ubiquity of mz 82 at other low NOx, high isoprene sites 

suggests mechanism important across all of the unpolluted tropics.

h h h• Suggestion is that there is an enhancement in presence of acids notably from sulphate

• Anal sis s ggests that an a erage of 23% (0 18 gm‐3)• Analysis suggests that an average of 23% (0.18 ugm‐3) and up to 53% (0.5 ugm‐3) of the organic aerosol may be produced from isoprene oxidation in Borneoproduced from isoprene oxidation in Borneo