Direct (Primary) and Indirect (Secondary) Emissions from Biomass and Prescribed Burning

Karsten Baumann

School of Earth and

Atmospheric Sciences

kb@eas.gatech.edu

22 January, 2004

Funded in part by DoD/EPA/State P2 Partnership Small Grants Program.

Co-authors: Mei Zheng, Venus Dookwah, Sangil Lee, Michael Chang

Problem: ESA versus CAA

Military Installations in SE-US occupy habitat of endangered species (red-cockaded woodpecker), and are required to maintain ecosystem by prescribed burning, risking violations of the NAAQS.

Clean Air Act

EndangeredSpecies Act

N

E

S

W10 20 µg m

-3

PM2.5 Eceedance at Columbus-OLC near Fort Benning for SE winds in Winter 2001/02

Manage 94,000 acr, Burn 1/3 per yr, ~ 520 acr/day

PM2.5 Exceedances at Columbus-OLC in Oct-Nov 2001

0.00

Win

d B

arb

40

30

20

10

0WS

(m

/s)

Tm

ax-T

min

(C) 80

60

40

20

0

8h

max O

3 (pp

bv)

ColumbusGIT OLCEPD AirptEPD Crlab

4

6

810

2

4

6

8100

2

4

24h

- P

M2.

5

(µg

m-3

)

10/21/01 10/31/01 11/10/01 11/20/01 11/30/01 12/10/01Time (EST)

1000

800

600

400

200

0

Ft B

enn

ing

(acr bu

rnt)

Griffin MaconAugusta Columbus

wild firesprescribed

Prescribed Burn Study: Objectives and Outlook

• In this initial pilot study, establish understanding of the direct and indirect impact of current burn practices on sub-regional Air Quality.

• Lay foundation for more comprehensive and better focused Phase II Study to optimize burn practices toward minimum AQ impact.

• Create results of general applicability for the benefit of LMBs on other military installations in the SE-US and beyond.

• Learn lessons that help create and implement new revised land management strategies for the benefit of other agencies and institutions that face often times devastating wild fires in other parts of the Nation.

Issues on Local to Global ScalesIn the continental U.S. prescribed burns and forest fires contribute ~37 % to the

total direct fine PM emissions of ~1 Mio t per year*

* Nizich et al., EPA Report 454/R-00-002 (NTIS PB2000-108054), RTP, NC, 2000

Effects on• Health

• Visibility• Air Quality

• Climate

Do prescribed burns reduce the risk

of wild fires?

To what extent does prescribed burning impact local and regional air quality?

VOCs

PMNOx

O3, SOA

Toxics

COCO2

Direct Emissions

1. Savannah GrassLobert et al, Nature 346, 552-554, 1990. Crutzen and Andreae, Science 250, 1669-78, 1990.

Flaming SmolderingCO2 CONOx NitrilesSO2 (HCN, CH3CN)N2O CH4, NMHC

CO/NOx ~ 25, SO2/NOx ~ 0.1

2. Wood/Coal BriquetsStruschka et al, IVD-RdL Univ Stuttgart, Rep.34, 1995

Flaming SmolderingCO/NOx SO2/NOx CO/NOx SO2/NOx

Wood 18 +-9 0.2 +-0.1 48 +-17 0.3 +-0.3Coal 9 +-5 23 +-6 50 +-40 18 +-12

Influence on Remote Locations

400

300

200

100

CO

(

pp

bv

)

121086420NOy (ppbv)

LB Lakes, KY 120 maslslp = 50.2 ±7.1icpt= 123 ±23(R= 0.64)

3000

2500

2000

1500

1000

500

0

CO

(

pp

bv

)

200150100500NOy (ppbv)

Nashville 1995 fire vs all:slp = 10.8 ±0.5 8.3 ±0.14icpt= 215 ±12 202 ±4.9 (R=0.91) (R= 0.90)

Nashville 1994:slp = 9.8 ±0.03icpt= 127 ±1.6(R= 0.96)

400

300

200

100

CO

(

pp

bv

)121086420

NOy (ppbv)

Cove Mt., TN 1250 maslslp = 39.5 ±2.6icpt= 124 ±9.4(R= 0.86)

1600

1400

1200

1000

800

600

400

200

0

CO

(p

pb

v)

100806040200

NOy (ppbv)

Hendersonville downwindfrom Nashville 1994:slp = 11.9 ±0.08icpt= 102 ±1.2(R= 0.89)

Canadian Forest Fires Impacting SE-US in Summer 1995Wotawa and Trainer, Science 288, 324-328, 2000.Open symbols: period 6/30 – 7/4.Increased regional CO background level!Is typically 80-90 ppbv.

Influence on urban areas:- less on slope (mobile src) - more on intercept !Shorter lifetime of NOy: some species (eg HNO3) lost due to surface deposition during transport in PBL.

Regional CO vs Burn Activity in GA during PBS

140

160

180

200

220

240

Dec-02 Jan-03 Feb'03 Mar'03 Apr'03 May'03 June'03

Month

CO

(p

pb

v)

0

5,000

10,000

15,000

20,000

25,000

Bu

rned

Acr

es

Ft Benning (acr)Surr Region (acr)Rest of GA/10 (acr)Ft Gordon (acr)Surr Region (acr)CO bkgrd (ppbv)

Monthly average CO background level derived from CO/NOy regressions at OLC (left) in comparison with prescribed burn areas at Forts Benning and Gordon, their surrounding

counties, and the rest of Georgia (only 10% of true area plotted!).

Direct Emissions of VOCs

Mixing ratios enhanced above local background at Fort Gordon TA21.Fuel: 230 acres of 2 year rough of pine needles, leaves, and woody debris.

0.0

0.1

1.0

10.0

100.0

1000.0

10000.0

100000.0

FLaming (3 h) Smoldering (6 h)

pp

mv,

pp

bv

CO2/COx (%) CO2 CO CH4 AlkanesAlkenes Aromatics Halog HC Biog HC Org NO3

VOC Emission Estimates - Comparison with Mobile Sources

0

1

10

100

1000

10000

Flaming Smoldering Gas Diesel Flaming Smoldering Gas Diesel

Fort Gordon Richmond Fort Benning Muscogee

Em

issi

on

s (

kg

/bu

rn/d

ay

)

Toluene m-Xylene p-Xylene o-Xylene 3-Ethyltoluene4-Ethyltoluene 2-Ethyltoluene Isopropylbenzene Propylbenzene Ethylbenzene

0

10

20

30

40

50

60

70

80

90

100

Flaming Smoldering Gas Diesel Flaming Smoldering Gas Diesel

Fort Gordon Richmond Fort Benning Muscogee

P(S

OA

)-F

rac

tio

n (

%)

Toluene m+p-Xylene o-Xylene 3-Ethyltoluene 4-Ethyltoluene2-Ethyltoluene Isopropylbenzene Propylbenzene Ethylbenzene

Average emissions per burn (~500 acr) compare with daily mobile emissions !3,4-E.toluene higher during smoldering,2-E.toluene highest for gasoline fueled vehicles

Contribution to P(SOA) potential is highest for Toluene from flaming and Xylenes from smoldering, minimal for 2-E.toluene.

Mas

s E

mis

sion

Rat

e (g

/kg

of b

iom

ass

burn

ed)

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15Carbonyls Cyclic compounds Branched Alkanes n-Alkynes Aromatics n-Alkanes n-Alkenes

Pinu

s tae

da

Tsug

a he

tero

phyl

la

Pinu

s pon

dero

sa

MH

FF

FPSP

WG

LP

Biomass Litter CompositesMHFF… mixed hardwood (oak) forest foliageFPSP… Florida palmetto & slash pineWGLP… wiregrass & longleaf pine

Direct (Primary) PM Emissions from Foliar Fuel Combustion in Lab

Hays, Geron et al., ES&T 36, 2281-2295, 2002

POC

High-Vol Sampling and GC/MS AnalysesQuantification of >100 Particle-phase Organic Compounds

RetenePimaric acidAbietic acidSandaracopimaric acidLevoglucosan

0

100

200

300

400

500

600

700

2/5/03 12:00 2/5/03 17:00 2/5/03 22:00 2/6/03 3:00 2/6/03 8:00

Sample Start Time [EST]

Co

nc

en

tra

tio

n (

ng

m-3

)

n-Alkanes Hopanes Steranes

PAHs Resin acids Arom carboxy acids

Other compounds Levoglucosan Branched alkanesn-Alkanoic acids Alkenoic acids Alkanedioic acids

Five consecutive 5-h samples taken at OLC between February 5th 1200 and 6th 1300

Influence from February 5th Burn: Source Apportionment

1200

1000

800

600

400

200

0

CO

(pp

bv) P

B (acres)

2/2 2/3 2/4 2/5 2/6Sun Mon Tue (m/dd) Wed Thu

60

50

40

30

20

10

0

NO

NO

y O

3 (

pp

bv)

16

12

8

4

0

PM2.5

(g m-3

) Un-ID Others LOA OOE OC EC NH4+ NO3- SO4=

8

4

0WS

(m

s-1

)0.00

-20

-10

0

10

20

amb

T (C

)

Low P front moving through GA on 3rd and 4th, with cold dry air moving in behind it from NE, causing below normal T under clear skies. Prescribed burning of 937 acres on 2/5 1200 at ~28 km to east, smoldering until 2/6 am. 0

1

2

3

4

5

6

7

8

2/5 1200 2/5 1700 2/5 2200 2/6 0300 2/6 0800Sample Start Time (EST)

Org

an

ic C

arb

on

(u

g m

-3)

Diesel exhaust Gasoline exhaust Wood combustion

Vegetative detritus Other OCNighttime avg

53% wood

?

?

VOCs

PMNOx

O3, SOA

Toxics

COCO2

Secondary organic aerosol (SOA):Organic compounds, some highly oxygenated, residing in the

aerosol phase as a function of atmospheric reactions that occur in either gas or particle phases.

SOA formation mainly depends on:Emissions & forming potential of precursors

aromatics (BTX, aldehydes, carbonyls)terpenes (mono-, sesqui-)other biogenics (aldehydes, alcohols)

Presence of other initiating reactantsO3, OH, NO3, sunlight, acid catalysts

Mechanisms (with half hr to few hr yields):Gas-to-particle conversion/partitioning

e.g. terpene oxidationHeterogeneous reactions

aldehydes via hydration and polymerization, forming hemiacetal/acetal in presence of alcohols

Particle-phase reactionsacetal formation catalytically accelerated by particle sulfuric

acid (Jang and Kamens, ES&T, 2001)

Photochemical Processes Leading to O3 and PM

SOA

NOz

An Assessment of Tropospheric Ozone Pollution, A North American Perspective, NARSTO, National Acad. Press, 2000.

0

5

10

15

20

25

30

35

20-Ja

n

21-Ja

n5-F

eb6-F

eb

10-M

ar

24-M

ar

27-M

ar

13-Apr

15-Apr

17-Apr

29-Apr

29-M

ay

Period

PM

2.5

(g

m-3

)

[K+] [Na+] [Ca2+] [NH4+] [Cl-] [NO3-] [SO4-2] EC Acetate Formate Oxalate OC OOE

PM2.5 Mass & CompositionIndividual Burn Events and Acres Burned

January May 2003

No-Burn Background

937 acres

1256 acres

3770 acres 4006 acres

504 251

Burning early in the season seems advantageous

PM2.5 Mass & CompositionOM/OC & [O3-max] Averages per Burn Event

January May 2003

0

5

10

15

20

25

Jan

Feb

Mar

, 1st

Mar

, 2nd

Apr, 1

st

Apr, 2

ndM

ay

Period

PM

(

g m

-3)

0

10

20

30

40

50

60

70

80

90

100

O3 (p

pb

v)

Others [NH4+] [NO3-] [SO4-2] EC LOA OC OOE Max O3

OM/OC 1.9 1.5 2.2 1.6 1.9 2.1 2.0

Higher PM mass and OM/OC with higher [O3] later in the season

PM2.5 Wind Roses: Seasonal Differences Across GAIndications for Regional Transport?

34.4

34.2

34.0

33.8

33.6

33.4

33.2

33.0

32.8

32.6

32.4

32.2

32.0

-85.5 -85.0 -84.5 -84.0 -83.5 -83.0 -82.5 -82.0

Atlanta

FAQS measurement sites GA-EPD monitoring sites coal burning power plants point sources w/ CO:NOx > 1

20x20 km

N

E

S

W9 18

µg m-3

15.813.4Griffin

Period 2001+ 02MAY-OCT NOV-APR

N

E

S

W9 18

µg m-3

16.715.5Macon SBP

N

E

S

W9 18

µg m-3

Columbus OLC 16.6 19.3

N

E

S

W9 18

µg m-3

15.014.2Augusta RP

…Similarity to Daytime O3

34.4

34.2

34.0

33.8

33.6

33.4

33.2

33.0

32.8

32.6

32.4

32.2

32.0

-85.5 -85.0 -84.5 -84.0 -83.5 -83.0 -82.5 -82.0

Atlanta

FAQS measurement sites GA-EPD monitoring sites coal burning power plants point sources w/ CO:NOx > 1

20x20 km

Period 2001+ 02MAY-OCT NOV-APR

N

E

S

W30 60

ppb

38.228.5Macon SBP

N

E

S

W30 60

ppb

Columbus OLC 30.7 19.8

N

E

S

W30 60

ppb

30.222.2Augusta RP

N

E

S

W30 60

ppb

44.236.1Griffin

Findings Progressively increasing fine PM mass and organics fraction correlate with increased temperature, solar radiation, and O3, indicating increased oxidizing potential, hence increased potential for SOA formation.

Strongest direct impact from prescribed burning emissions at OLC site encountered at night under clear skies nocturnal inversion and slow moving easterly component flow (along the Upatoi Creek); the contribution from the PB source indicators is then ~52 % to total OC.

VOCs with low Ps (C>6), esp. toluene and xylenes are being emitted at similar quantities per average burn day than the daily emissions of the mobile sources of the respective county, Muscogee (Fort Benning) and Richmond (Fort Gordon); the P(SAO) potential is highest for toluen followed by xylenes.

The regional CO background is closely correlated with open burning activities in Georgia, suggesting i) substantially longer smoldering phases than originally assumed, ii) similar source behavior across the entire SE-US??

Supplementary Material

Seasonal Differences in Diurnal Cycles: O3 & PM2.5

00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00 00:00

Time (EST)

WINTER HALF NOV-APRMac '01/'02 '00/'01Col '01/'02 '00/'01Aug '01/'02 '00/'01

WINTER HALF NOV-APRGrif '01 Tift '01Mac '01 '00Col '01 '00Aug '01 '00

PM2.5 Sources Near Columbus Driving Nighttime Averages in Winter 2001/02

Winter

25

20

15

10

5

0

PM

2.5

(

g m

-3)

00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00 00:00

Time (EST)

SUMMER HALF MAY-OCTGrif '02Mac '02 '01 '00Col '02 '01 '00Aug '02 '01 '00

70

60

50

40

30

20

10

0

O3

(pp

bv)

SUMMER HALF MAY-OCTTift '02 '01Grif '02 '01Mac '02 '01

'00Col '02 '01

'00Aug '02 '01

'00

Summer

OLC site upgradeResearch site at

Oxbow Meadows Environmental Learning Center

upgraded for PM source apportionment and in situ

gas phase sampling

3’

4’

a/c

11’

8’

Stair step

4’ 14’

Guy wired8m Towertilt down

10’ Gate

45’ x 40’ Fence

N

10’ x 12’ Shelter

4 additional 20 A circuit breakers

33’ x 7’ level Platform~ 1’ above ground

4 quadruple outlets on individual breakers

Particle Composition Monitor “PCM”

Channel 1:

NH3

Na+, K+, NH4+, Ca+2

Channel 2:

HF, HCl, HONO, HNO3, SO2,

HCOOH, CH3COOH, (COOH)2

F-, Cl-, NO3-, SO4

=,

HCOO-, CH3COO-, C2O4=

Channel 3:

EC, OC, WSOC, “SVOC”

Additional higher resolution

CO, NO, NOy, O3, PM-mass,

and basic meteorology

Canister Sampling and GC/FID Detection of Volatile Organic Compounds

VOC

Collaborating withProf. Don Blake, UC Irvine, CA 92697 http://fsr10.ps.uci.edu/GROUP/group.html

C2-C6 n-alkanes, alkenes, branched alkenes, alkynesisoprene

Cyclic compoundsmonoterpenes (-, -pinene)

Aromatics, organic nitrates, halogenated speciesmethylchloride

Quantification of >60 compounds, incl. CO2 for “fire” samples

Other OrganicCarbon{SOA}30%

WoodCombustion

39%

MeatCooking

6%

VegetativeDetritus

2%

GasolineExhaust

3%

Diesel Exhaust 20%

Source Contributions to Organic Carbon (OC)in Ambient PM2.5

Pensacola, FL October 1999Measured average [PM2.5] = 16.6 g m-3

[OC] = 4.6 g m-3

Zheng et al., ES&T 2002