The Southern Oxidant and Aerosol Study

Annmarie G. Carlton

Southeast Atmosphere StudiesJune 1 - July 15, 2013

Additionally: EPA’s surface networks, NASA satellites, EPRI network

Smog over Birmingham, TSP ~700 μg m-3.

EPA’s first implementation of the CAA’s

“emergency powers” provision. (The

Birmingham News file/Dave Battle)

40 years later EPA proposed that

Birmingham be certified as

having attained the NAAQS.

Stagnation event 1971

Great Smoky Mountain National Park

Photo courtesy of CIRA

Pre SOS in 1990 Post SOS in 2010

Southern Oxidant and Aerosol StudyJune 1 - July 15, 2013 SOAS + SENEX + TropHONO + NAAMEX = Southeast Atmosphere Studies (SAS)C130 portion of SOAS + TropHONO + NAAMEX = NOMADSS

NSF, NOAA, EPA, EPRI, NCAR, U.S. and European Universities, private companies worked together during the sequester(!).

NSF OFAP request: 160 hours on C130, 2 towers, 110 release sondesand individual investigator proposals

NOAA’s commitment to fly the P3 for SENEX was an early and important impetus

EPA’s anthropogenic influence on PM in the Southeast STAR RFP supported of SOAS. University scientist funded to fly on a NOAA plane

Main ground site is EPRI’s “CTR” SEARCH network site.

SEACR4S campaign repeated some P3 and C130 flight tracks later in summer, extending the intensive period for chemical characterization of the troposphere

SAS timeline

Informal community discussions: Telluride, CO Aug. 2010; AGU, Dec. 2010; J. de Gouw

2010 2011 2012 2013 2014

“SOAS” Rutgers workshop May 2011: EPA: R. Pinder, K. Baker, NOAA: J. de Gouw,

S. Brown; DOE: L. Kleinmann, J. Wang

SENEX campaign announced

AGU Town Hall on SOAS

SOAS OFAP

proposal is accepted,

shares C130 with

TropHONO and

NAAMEX

SOAS/SAS

SOAS

White

Paper

AGU session

(6 sessions) AGU

session

Joint with SEACR4S

(5 sessions) SAS data workshop

AAAR

special

symposium

S. Hunt presentation at AQRS

Overwhelming majority of organic compounds in the atmosphere come from the biosphere. Biogenic hydrocarbons interact with anthropogenic pollution to form pollutants ozone, even resulting in non-attainment.

Last time our community converged on the Southeast U.S. AQ management redefined for O3

– As late as 1988: literature describing how VOC controls are not working for

Atlanta O3: NOx-limited and VOC-limited

– Isoprene is 3% by mass of Atlanta’s VOC inventory, but >30% of the reactivity

SOS Reminders

+ = O3

Emissions from the biosphere interact with emissions from human activity to form particulate matter. Anthropogenic pollution facilitates biogenic SOAformation (Weber et al., 2007; Surratt et al., 2007; Lane et al., 2009; Jimenez and de Gouw, 2009; Carlton

et al. 2010; Spracklen et al., 2011; Shilling et al., 2013).

Motivation behind SOAS in 2013.

+ =

What are the magnitudes,

variations, and controlling

processes for biosphere-

atmosphere fluxes of

oxidants, reactive C & N

across spatial scales

relevant to AQ and climate?

BVOC

Biogenic

SOA

Aqueous

chemistry &

cloud

processing

How does

aqueous

chemistry and

cloud

processing of

BVOCs and

aerosols

influence SOA

properties?

What are the

phys/chem processes

that control BVOC

oxidation? How do

anthropogenic

emissions alter the

distribution of the o-

BVOCs, and what are

the implications for O3,

reactive nitrogen, and

aerosol precursors?

Climate

What are the climate-relevant

properties of BSOA

Precursor

Gases and

aerosol

NOx

SOAS

To what extent do

anthropogenic

influences impact

biogenic (VOC)

SOA formation?

What are the magnitudes,

variations, and controlling

processes for biosphere-

atmosphere fluxes of

oxidants, reactive C & N

across spatial scales

relevant to AQ and climate?

BVOC

Biogenic

SOA

Aqueous

chemistry &

cloud

processing

Climate

Precursor

Gases and

aerosol

NOx

SOAS

What is the composition and

distribution of aerosol in the

SE U.S.?

What are the

emissions of

aerosol, aerosol

precursors and

greenhouse

gases in the SE

U.S.?

What are the formation

mechanisms of

secondary species (O3

SO4 and organics) in

the SE U.S.?

Which deposition processes

are critical for atmospheric

concentrations of aerosol,

O3 and NOy?

What are the climate-relevant properties of aerosol in the SE U.S.?

SENEX

GHGs

What are the climate-relevant

properties of BSOA

How does

aqueous

chemistry and

cloud

processing of

BVOCs and

aerosols

influence SOA

properties?

To what extent do

anthropogenic

influences impact

biogenic (VOC)

SOA formation?

What are the

phys/chem processes

that control BVOC

oxidation? How do

anthropogenic

emissions alter the

distribution of the o-

BVOCs, and what are

the implications for O3,

reactive nitrogen, and

aerosol precursors?

What are the magnitudes,

variations, and controlling

processes for biosphere-

atmosphere fluxes of

oxidants, reactive C & N

across spatial scales

relevant to AQ and climate?

BVOC

Biogenic

SOA

Aqueous

chemistry &

cloud

processing

Climate

Precursor

Gases and

aerosol

NOx

SOAS

What is the composition and

distribution of aerosol in the

SE U.S.?

What are the

emissions of

aerosol, aerosol

precursors and

greenhouse

gases in the SE

U.S.?

What are the formation

mechanisms of

secondary species (O3

SO4 and organics) in

the SE U.S.?

Which deposition processes

are critical for atmospheric

concentrations of aerosol,

O3 and NOy?

SENEX

GHGs

HONO

pNO3

Establish tropospheric HONO

distribution and budget in various

air masses (continental, oceanic,

urban/industrial plumes).

Collect bulk aerosol samples for

laboratory photochemical

experiments to measure photolysis

rate constants of p-NO3 leading to

HONO and NOx.

Quantify p-NO3 as

daytime HONO

source and a re-

NOx-ification

pathway in the

troposphere.

Examine HONO production

from photo-enhanced

heterogeneous NOx

reactions in urban/industrial

plumes.

Investigate HONO dark formation/nighttime

accumulation and morning-hour photolytic decay

in the PBL and in the FT.

TROPHONO

What are the climate-relevant properties of aerosol in the SE U.S.?

What are the climate-relevant

properties of BSOA

How does

aqueous

chemistry and

cloud

processing of

BVOCs and

aerosols

influence SOA

properties?

To what extent do

anthropogenic

influences impact

biogenic (VOC)

SOA formation?

What are the

phys/chem processes

that control BVOC

oxidation? How do

anthropogenic

emissions alter the

distribution of the o-

BVOCs, and what are

the implications for O3,

reactive nitrogen, and

aerosol precursors?

What are the magnitudes,

variations, and controlling

processes for biosphere-

atmosphere fluxes of

oxidants, reactive C & N

across spatial scales

relevant to AQ and climate?

BVOC

Biogenic

SOA

Aqueous

chemistry &

cloud

processing

To what extent do

anthropogenic

influences impact

biogenic (VOC)

SOA formation?

Climate

Precursor

Gases and

aerosol

NOx

SOAS

What is the composition and

distribution of aerosol in the

SE U.S.?

What are the

emissions of

aerosol, aerosol

precursors and

greenhouse gases

in the SE U.S.?

What are the formation

mechanisms of

secondary species (O3

SO4 and organics) in

the SE U.S.?

Which deposition processes

are critical for atmospheric

concentrations of aerosol,

O3 and NOy?

What are the climate-relevant properties of aerosol in the SE U.S.?

SENEX

GHGs

HONO

pNO3

Establish tropospheric HONO

distribution and budget in various

air masses.

Collect bulk samples for laboratory

photochemical experiments to

measure photolysis rate constants

of p-NO3 leading to HONO and

NOx.

Quantify p-NO3 as

daytime HONO

source and a re-

NOx-ification

pathway in the

troposphere.

Examine HONO production

from photo-enhanced

heterogeneous NOx

reactions in urban/industrial

plumes.

Investigate HONO dark formation/nighttime

accumulation and morning-hour photolytic decay

in the PBL and in the FT.

TROPHONO

Hg0

Constrain

emissions of Hg

from major

source regions

in the US.

Hg2+

Quantify distribution &

chemical transformations of

speciated Hg in the

troposphere.

NAAMEX+ + + = Southeast Atmosphere Studies (SAS)

What are the climate-relevant

properties of BSOA

How does

aqueous

chemistry and

cloud

processing of

BVOCs and

aerosols

influence SOA

properties?

What are the

phys/chem processes

that control BVOC

oxidation? How do

anthropogenic

emissions alter the

distribution of the o-

BVOCs, and what are

the implications for O3,

reactive nitrogen, and

aerosol precursors?

RH + OH R RO2

O2+NO

+HO2

+RO2

“Big” Picture

VOCs + NOx + hv O3 + particles + …

“High NOx”

“Low NOx”

Model predictions must correctly predict concentrations for the rightreasons. This is essential to ensure appropriate model response tosimulated control strategies and is critical to development of cost-effective air quality management plans.

+NO3

Moving Forward

Reaching across scientific discipline workhsop at GFDL: “Southeast Atmosphere Studies Workshop: Intensive Observation Period Modeling to Improve Mechanistic Representation of Trends”

Are we still asking the most critical and open important science questions?

What are high level questions we can answer with our robust data set? Are we getting the most out of this resource?

What are the important scientific details can we “finally figure out” and “nail down”?

How do we impact future the development of effective air quality management strategies?

Organic Aerosol Formation in the Humid,

Photochemically-Active Southeastern US: SOAS

Experiments and Simulations

Barbara Turpint, Annmarie Carlton, Neha Sareen

Rutgers University – New Brunswicktnow at University of North Carolina – Chapel Hill

ANTHROP

OGENIC

BIOGENIC

Organic+Oxidants:Gases.OH,O3,NO3

Water-solublegases

Water-solublecompounds

+.OH

(Aqueous-phase)

SecondaryOrganicAerosol(SOAAQ)Clou

dDrople

t

Evapora

on

(Par cle-phase)

H2O

H2O

.OH

.OH.OH

.OH

.OH

.OH

.OH

.OH.OH

.OH

.OH.OH

Brent,AL

Dept of Environmental SciencesTurpin–Carlton Specific Aims - SOAS:

1) Model aerosol liquid water concentrations

2) Model water-soluble gases

3) Conduct aqueous OH oxidation experiments with

ambient SOAS mixtures of water-soluble gases

(WSOG) to identify precursors/products

4) Collaborate, provide intellectual leadership and

share data to achieve the SOAS science goals

Condensation

VOC Oxidant (O3, OH, NO3

,…) SOA+

SVOC1,2, …

WSOC1,2, …

(isoprene,monoterpenes,

SESQ)

VOCs + NOx + hv O3 + particles + …

Polar gases also partition to polar solvents water SOAaq

Majority of partitionable atmospheric organic compounds are small, water-soluble gases (Grosjean et al., 1996; Nolte et al., 2001: Zhang et al., 2007) and globally, particle phase liquid water mass >>2-3x organic aerosol mass (Liao and Seinfeld, 2007).

Why is Southeastern U.S. the ideal region for this study?

condensed-phase𝐬𝐞𝐦𝐢𝐯𝐨𝐥𝐚𝐭𝐢𝐥𝐞𝐨𝐫𝐠𝐚𝐧𝐢𝐜𝐬

gas-phase𝐬𝐞𝐦𝐢𝐯𝐨𝐥𝐚𝐭𝐢𝐥𝐞𝐨𝐫𝐠𝐚𝐧𝐢𝐜𝐬

Lots of aerosol water Lots of WSOCg (glyoxal …) Lots of semi-volatile organic compounds

[Carlton and Turpin, 2013, ACP]

WSOCgWSOCp CMAQ used in site selection

CMAQ predictions for all of the ground sites extracted and uploaded to ftp in ICARTT format

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0 2 4 6 8 10 12 14 16 18 20 22

0

10

20

30

40

50

Hours past midnight

Wate

r µg/m

^3

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Water model comparison for SOAS

ISORROPIA SMPS

Wate

r (µ

g m

-3)

Hours past midnight

ISORROPIA ran with measured data input SMPS data from Nguyen et al., 2014

adjusted to SEARCH RH using P&K eqn.

RH < 99%

CMAQ Modeling

• CMAQv5.0.1

• June 6-June 15 2013

• SAPRC07 updated with “explicit” isoprene gas

phase oxidation chemistry (Xie et al., ACP, 2013)

• Heterogeneous organic chemistry (Pye et al., ES&T, 2013)

• WRFv3.4

• BEISv3.14

• Point and other anthropogenic species based on

NEI2008v3.1 and “grown” (forecasting ‘runs’)

• 12km x 12km grid for the ConUS

accumulation mode organic PM

AOLGB

AORGC

∙OH

dis

solu

tio

n

cloud water

VOCs

EMIS

SIO

NS

EMIS

SIO

NS

isoprene

sesquiterpenes

monoterpenesSV_TRP1

SV_ISO1

SV_SQT

+O3P, NO3

+∙OH

pathways do not contribute to SOA

+∙OH,O3

ASQT

ATRP1

AISO1

EMIS

SIO

NS

SV_TRP2

SV_ISO2 AISO2

+HO2ISOPOOH

+OH

IEPOX

AIETET

+H2O

AIEOS+SO4

2-

AIEON+NO3-

AIDIM

+NO MACR

+OH,NO2

MPAN +∙OH MAE + HMML

AIMGA

AIMOS

AIMON

ATRP2

SOA formation pathways from biogenically-derived VOCs in CMAQ’s AERO 6

+O3 O3P, NO3

Glyoxalmethylglyoxal

(Xie et al., ACP, 2013) (Pye et al., ES&T, 2013)

WSOG species SV species

• Formaldehyde (HCHO)

• Acetone (ACETONE)

• Acetaldehyde (CCHO)

• Methyl ethyl ketone (MEK)

• Methyl vinyl ketone (MVK)

• Methacrolein (MACR)

• Glyoxal (GLY)

• Methylglyoxal (MGLY)

• Acetic acid (CCOOH)

• Methanol (MEOH)

• Isoprene epoxydiol (IEPOX)

• Methacrylic acid epoxide (MAE)

• Hydroxymethylmethyl-α-lactone (HMML)

• Alkane (SV_ALK)

• Xylene (SV_XYL*)

• Toluene (SV_TOL*)

• Benzene (SV_BNZ*)

• Terpene (SV_TRP*)

• Isoprene (SV_ISO*)

• Sesquiterpene (SV_SQT)

* multiple species

20

0

10

ppb

0

1

2

WSOG species

Surface layer

Semi-volatile species

CMAQ modeling

WSOG species4000

0

2000

ppb

0

200

400

Vertical total

Semi-volatile species

CMAQ modeling

[Ci]p=HiRTLCi(g)

35

30

25

20

15

10

5

0

WS

OG

(p

pb

V)

6/6

00:0

0

12:0

06/7

00:0

0

12:0

06/8

00:0

0

12:0

06/9

00:0

0

12:0

06/1

0 0

0:0

0

12:0

06/1

1 0

0:0

0

12:0

06/1

2 0

0:0

0

12:0

06/1

3 0

0:0

0

12:0

06/1

4 0

0:0

0

12:0

06/1

5 0

0:0

0

12:0

0

Time

3.5

3.0

2.5

2.0

1.5

1.0

0.5

0.0

SV

(p

pb

V)

WSOG SV

At surface layer, model predicts WSOG an order of magnitude

greater than semi-volatile species at Brent ground site

SV

WSOG

35 3.5

Modeling Summary

IEPOX is only recently discovered in ambient PM and modeling results suggest it dominates the WSOCg in wet aerosols in the SEU.S.

Model estimates depend on organic gas ‘solubility’, the extent to which this is accurately predicted remains an open question.

What happens to the partitioned material Barbara Turpin

Log [Po atm]

-7 -6 -5 -4 -3 -2 -1 0

O/C

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Isoprene

O

Methacrolein

O

MVK

HO

O

C5 Hydroxy

carbonyl

OH

OOH

OH

HO

O

OH

Recycling

OrgPeroxEpoxide

OO

MGLY

OO

GLY

OHO

Glycolaldehyde

1st

G Products

1st

G Products

2nd

G Products

OH (Fragmentation)(Oxidation)

(Fragmentation)OH

3hrs

10-14hrs

3hrs1.3 days

1-3 days

OH

Example: isoprene + OH radicals

Expect gas phase chemistry to produce WS gases

Dept of Environmental SciencesLab experiments with selected precursors

Wet aerosols:

acid and ammonium catalyzed oligomerization

organosulfate formation

radical-radical reactions

Dilute cloud chemistry:

Oxidation – organic acid formation

Droplet evaporation:

e.g., amines and aldehydes

What are the important precursors in the

real atmosphere? Can we identify more?

Dept of Environmental SciencesTurpin–Carlton Specific Aims - SOAS:

1) Model aerosol liquid water concentrations

2) Model water-soluble gases

3) Conduct aqueous OH oxidation experiments

with ambient SOAS mixtures of water-soluble

gases (WSOG) to identify precursors/products

4) Collaborate, provide intellectual leadership and

share data to achieve the SOAS science goals

Mist Chamber Sampling at SOAS

in

WSOG mix close to Henry’s law equilibrium

based on WSOG vs collection time before campaign

and 1 run with 2 in parallel (w/in 11%)

FT ICR MS-MS

10000

8000

6000

4000

2000

CIM

S s

ign

al

35x103302520151050

Time (s)

Background25°C 39°C

56°C

74°C

93°C

114°C

140°C

160°C

Oxalic acid Formic acid

Glyoxal CSTR mimic pH 7

10000

8000

6000

4000

2000

CIM

S s

ign

al

45x1034035302520151050

Time (s)

Background 25°C

39°C

56°C

74°C

93°C

114°C

(Oxalic acid)

(Formic acid)

Glyoxal CSTR mimic pH 3

± NH4OH

Ortiz-Montalvo et al., ES&T 2013

Oxalic acid likely to

remain in gas phase

at SOAS

CIMS

Evolved

oxalic acid

pH 3

CIMS

Evolved oxalic acid

pH 7

Gas-phase oxidation of 2-hexenal (or 3-hexenal)

O O

OH

OH

O’Conner et al., PCCP 2006

O

HO O

OH

Gas-phase oxidation of (E)-2-methyl but-2-enal

Jimenez et al., AE 2009

Lanza et a.,, CPL 2008

IEPOX – signature peaks in ESI-MS(+)

60x103

50

40

30

20

10

0

ES

I- M

S a

bu

nd

acn

e

40035030025020015010050

m/z (+)

3000 µM IEPOX 300 µM IEPOX DI blank

71

83

101

141

159

237

259

377

197201 219 297

[IEPOX + Na + H2O]+

[IEPOX + Na]+

IEPOX not seen in SOAS mist chamber samples – but is seen by ESI-MS

•Tentatively identified OH-reactive water soluble polyols,

possible oxidation products of isoprene, green leaf

volatiles

•IEPOX, ISOPOOH probably too reactive to be preserved

in the mist chamber samples

•Complex WSOG mixtures produced oxalate, pyruvate

•Cloud-produced oxalate probably in gas phase at SOAS,

in particle phase if a salt

We conclude:

Carlton, ….Turpin et al. (2016) The Southeast Atmosphere Studies (SAS):

Coordinated Investigation and Discovery to Answer Critical Questions about

Fundamental Atmospheric Processes, Bulletin of the American

Meterological Society, in preparation.

Sareen, N., Carlton, A.M.G., Felipe, H., Lopez-Hilfiker, D., Mohr, C.,

Thornton, J.A., Zhang, Z., Gold, A., Surratt, J.D., Lim, Y.B., Turpin, B.J.

(2015) Identifying precursors and aqueous organic aerosol formation

pathways during the SOAS campaign, Atmospheric Chemistry Physics

Discussion, submitted.

Sareen, N., Waxman, E.M., Turpin, B.J., Volkamer, R., Carlton, A.G. (2015)

Dominance of isoprene epoxydiol (IEPOX) as an aerosol precursor in the

Southeastern United States: model simulations, ES&T, in preparation.

EPA-STAR Publications

Acknowledgements

SOAS2013.rutgers.edu

NCAR’s EOL

ARA, Karsten Bauman

City of Brent, AL

Yong Bin Lim, Jeff Kirkland, Diana Ortiz,

Sara Duncan

Jason Surratt, Avram Gold, Zhenfa Zhang,

Faye McNeill, Joel Thornton

83541201