89-25.3 - FRAMES · Average emission factors for thirteen trace gases from the ftres are shown in Table II. The emission factors were derived using the carbon balance method [Radke

- ---

89-253

EMISSIONS OF SOME TRACE GASES FROM BIOMASS FIRES

DEAN HEGG~ LAWRENCE RADKE AND PETER HOBBS

UNIVERSITY OF WASHINGTON SEATTLE~ WASHINGTON

REI A RASMUSSEN

DEPARTMENT OF ENVIRONMENTAL TECHNOLOGY BEAVERTON~ OREGON

PHIUP J RIGGAN

US FOREST SERVICE RIVERSIDE~ CALIFORNIA

- shy -shy~-

AIR amp WASTE MANAGEMENT ASSOCIATION

bull SINCE 1907

For Presentation at the 82nd Annual Meeting amp Exhibition

Anaheim California June 25-30 1989

89-253

ABS1RACf

Airborne measurements of thirteen trace gases from seven forest fIres in North America are used to determine their average emission factors The emission factors are then used to estimate the contributions of biomass burning to the worldwide fluxes of these gases The estimate for NHa (-7 Tg N yr-l) is about 50 of the global emissions of this gas Combined NH3 and NH4 emissions from biomass burning could be the most important component of the NH3 cycle N2U from biomass burning (- 2 Tg N yr-l) is also signifIcant worldwide The estimate ror NOxfrom biomass burning worldwide (- 19 Tg N yr1) which is greater than previous estimates is comparable to emissions from fossil fuel combustion The estimate of the ~lobal flux of F12 (CF2Cl2) from biomass burning based on the complete data set (- 02 Tg yr- ) is - 50 of the total global emission of F12 However this estimate is strongly influenced by a very high emission of F~ from a fIre in the Los Angeles Basin Disregarding this fIre yields a global flux of 006 Tg yr- (15 of total global emissions) The high emissions of NOx and F12 are due in whole or part to the resuspension of previously deposited pollutants Since this can be the only source ofF12 in the smoke from fIres deposition may be a signifIcant sink for F12

Our estimate for NOx emissions from biomass burning in the South Coast Air Basin of California are much greater than previous estimates

INTRODUCTION

Emissions of trace gases from biomass burning are known to be an important source of several trace gases (eg C02 CO and CH4) in the atmosphere [eg Crutzen et aI 1985]1 Also the emissions from fIres can have a marked effect on local and regional air quality [eg Radke et al 1978]2 However quantitative estimates of the contributions of such emissions to the global budgets of various trace species are diffIcult to make For example Logan et al [1981]3 estimated that CO emissions from global biomass burning ranged from 310 to 1250 Tg CO yr-l Estimates are even more uncertain for species that are more diffIcult to measure (eg NOx)

In this paper we present measurements of some trace gas emissions from seven biomass fIres in North America Emission factors are calculated for some trace gases and estimates are made of the signifIcance of such emissions on global and local scales

FIRES STUDIED AND MEASUREMENT TECHNIQUES

The locations times sizes and fuel types for the seven fIres examined in this study are listed in Table I The fIres encompass a wide range of woody biomass fuel types including the rarely studied chaparral of the Southwest United States

The measurements were obtained from the University of Washingtons C-131A research aircraft The aircraft instrumentation package and samfling procedures have been described by Hegg and Hobbs [1980]4 and Hegg et al [1988a] Many of the trace gases discussed (eg hydrocarbons N20) were analyzed by gas chromatography using the methodologies described by Rasmussen et al [1974]6 and Khalil and Rasmussen [1988f

-2shy

89-253

Table 1 Fires examined in this study

Name Location Dates Size (ha) Fuel

Lodi 1 Los Angeles Basin 12 December 1986 40 Chaparral Chamise

Lodi2 Los Angeles Basin 22 June 1987 150 Chaparral Chamise

Myrtle Roseburg Oregon 2 September 1987 2000 Pine brush Fall Creek Douglas Fir

Silver Grants Pass Oregon 17-19 September 1987 20000 Douglas Fir True Fir Hemlock

Hardiman Chapleau Ontario 28 August 1987 325 Jack Pine AspenBirch

(Canada)

Eagle Ramona California 3 December 1986 30 Black Sage Sumac Chamisse

Battersby Timmins Ontario 12 August 1988 718 Jack pine White (Canada) amp Black Spruce

RESULTS

Emission Factors

Average emission factors for thirteen trace gases from the ftres are shown in Table II The emission factors were derived using the carbon balance method [Radke et al 1988]8 The carbon fraction of the wood was assumed to be 0497 [Byram and Davis 1959]9 The emission factors and standard deviations were computed from at least six measurements on each ftre

The intra-ftre variability in the emission factors commonly exceeds the inter-ftre variability This illustrates the importance of temporal variabilities in the ftres (eg flame temperature) on emissions We have noted this previously with regard to NH3 emissions [Hegg et al 1988b]1O This variability can obscure differences in emissions between fires due to fuel type

The average emission factors of the trace gases based on the measurements from all seven ftres have quite high standard deviations (Table Ill- For example the mean emission factor for CO is 91 plusmn 21 g kg-I Of the variance of 21 g kg- 23 is due to intra-ftre variability and the remainder to inter-ftre variability The uncertainties in the mean emission factors propagate through our estimates of the fluxes of the gases and our extrapolations to the global scale

-3shy

Tab

le II

A

vem

ge e

mis

sion

facl

Ors

(an

d st

anda

rd d

evia

tion

s) f

or v

ario

us tr

ace

gas

es fr

om s

even

bio

mas

s fi

res

in N

on

h A

mer

ica

Uni

ts a

re g

kg

-I

Fir

e C

O

CO

2 deg3

N

H3

CH

4 C

3

C2H

6 C

3Hg

C2

H2

N-C

411

N20

FIz

Y

NO

xll

Lod

i 1

74

plusmn 1

6 16

64 plusmn

44

14

plusmn 1

3 1

7 plusmn

08

2

Aplusmn

01

5 0

58 plusmn

O 0

5 0

35 plusmn

O1

2 0

21 plusmn

O1

2 0

32 plusmn

O0

5 0

11

plusmnO0

7 0

31 plusmn

O1

4 0

045

plusmnOO

W

89

plusmn3

5

Lod

i2

75plusmn1

4 16

5Oplusmn

31

019

plusmn 0

36

0

09

plusmn 0

04

36

plusmn0

25

O

A6plusmn

O0

3 0

55plusmnO

15

032plusmn

O1

2 0

21plusmnO

03

010

plusmnO

05

02

7plusmnO

31

0O

O9plusmn

O0

03

33

plusmn 0

8

Myr

tlel

10

6plusmn

20

1

62

6plusmn

39

-0

5 plusmn

02

2

0plusmn

09

3

0 plusmn

08

0

7plusmn

00

4

060

plusmnO

13

025

plusmnO

05

02

2plusmnO

04

002

plusmnO

04

000

25 plusmn

O0

015

254

plusmnO7

0 8

8 7

6

Fall

Cre

ek

Sil

ver

89

plusmn5

0

1637

plusmn 1

03

47

plusmn4

0

06plusmn

O 5

2

6plusmn

16

0

08 plusmn

00

1 0

56

plusmnO3

3 00

42 plusmn

Ol

3 0

19plusmn

O0

9 0

2plusmnO

1

027

plusmnO

39

00

081

plusmn 0

69

S1

U

I +0

I

Han

liman

8

2plusmn

36

16

64 plusmn

62

-05

plusmn 0

04

01

plusmn 0

07

19

plusmn0

5

058

plusmn 0

09

045

plusmnO

26

018

plusmnO

l3

03

1 plusmn

O3

5 0

02plusmn

O0

4 0

41 plusmn

O5

2 0

000

4 plusmnO

OO

O3

33

plusmn 2

3

90

7

Eagl

e 3

4plusmn

6

17

48

plusmn 1

1 6

5 plusmn

29

0

9 plusmn

02

0

25plusmnO

06

018

plusmnO

05

005

plusmnO

02

00

8 plusmnO

02

02plusmn

O0

8 0

16plusmn

O0

13

000

8plusmnO

003

7

2plusmn3

8

C~

Ban

ersb

y 17

5 plusmn

91

15

08

plusmn 1

61

-09

plusmn0

6

56

plusmn 1

7

09

plusmn 0

15

057

plusmnO

A5

027

plusmnO

12

033

plusmnO

06

007

plusmnO

06

105

plusmn1

33

1~~

F

2-

81yO~

Ove

rall

JrD

B

B3

3

8

2

lt o~

Ave

nge

E

mis

sion

9l

plusmn21

16

42plusmn3

7 3A

plusmn23

0

9Oplusmn0

A3

29

plusmn0

66

05

1plusmnO

14

047

plusmnO1

1 0

24plusmnO

06

024

plusmnO

04

010

plusmn0

05

028

plusmnO 0

5 0

01Iplusmn

O0

07

39

plusmn1

6

Fact

or

1 S

trai

ght c

hain

par

affi

n w

ith

carb

on n

umbe

r of

4

2 C

F 2Cl 2

00

~

3 N

O=

NO

+ N

02

I x

N

(J1

W

89-253

Global Significance of Emissions from Biomass Burning

If we had good estimates of the amount of biomass burned each year around the globe we could multiply this quantity by the emission factor for each of the gases given in Table II to obtain estimates of the contribution of biomass burning to the global emission fluxes of the gases Unfortunately biomass burning worldwide is not well quantified However estimates are available of the amounts of CO and C02 produced annually from biomass burning [eg Crutzen et al 19851 Mooney et al 1987]11 To utilize these estimates the relative emission ratio of each trace gas to CO (or C02) was determined from the data listed in Table II and then this number was multiplied by the estimated global emission flux of CO (or C02) from biomass burning to obtain estimates of the contribution of biomass burning to the global emission flux of the trace gas The emission factors for CO and C02 listed in Table II are in reasonable agreement with the values used by Logan et al [1981]3 and Andreae et al[1988]12 However since our estimates for CO~ emissions are somewhat higher than normally assumed we have used CO as our ratio species for estimating global fluxes

Listed in Table III are the derived values for the mean ratios of the emissions faetors for the various trace gas species to the emission factors for CO together with our estimates of the global fluxes into the atmosphere from biomass burning based on these ratios The valye for global CO emissions from biomass burninr utilized in the flux calculation was 800 Tg yr [Crutzen et al 1985]1 Using Radkes [1989]1 estimate for the amount of biomass burned globally (-I(11Tg yrshy1) and our emission factor for CO we obtain 910 Tg yr- 1 of CO worldwide from biomass burning

The fIrst species shown in Table III (03) is not emitted directly by fIres Rather it is created in the fIre plume by the chemical interaction of reactive hydrocarbons and NOx [Evans et al 197414 Radke et al 1978]2 A regression of the 03 emission factor onto the NOx emission factor for our data yields an intercept of -22 Tg yr- 1 a slope of 14 and a correlation coeffIcient (r) of 08 signifIcant at the 98 level This suggests an 03-production mechanism analogous to that in photochemical smog formation Furthermore the mechanism appears to be limited by the amount of NOx (ie there is insufficient NOx to react with the available reactive hydrocarbons) and thus the 03 production increases with increasing NOx [Dismitriodes and Dodge 1983]15 We can assess the globaljmpact of biomass burning on ozone as follows Based on a tropospheric volume of - 6 x 1018 m j (derived from the global surface area and typical tropopause heights [Hegg 1985] 16 and troposphere 03 concentrations of - 30-50 ppbv) we obtain a tropospheric 03 reservoir of - 150-200 Tg This reservoir has a variable turnover time depending on season ana latitude but is certainly no more than two weeks [Logan 1985]17 Total tropospheric 03

tproduction must therefore be on the order of - 4000 Tg yr- Therefore the global flux of 03 shown in Table III (48 Tg yr 1) constitutes a very minor source of tropospheri103

Our estimate of the flux of NH3 from biomass burning (-8 Tg yr- ) suggests that it contributes signifIcantly to the atmospfieric reservoir of NH3 Since we have addressed this point previously [Hegg et al 1988a]5 we will not dwell on it here except to note that the present measurements support our contention that biomass burning is an importantr source of NH3

Andreae et al [1988] 12 measured significant fluxes of particulate NH4 from biomass fires in the Amazon Basin and suggested that if (as seems likely) these emissions also contained substantial amounts of gaseous NH3 (whiCh they did not measure) biomass burning would have a very substantial imfact on the global NH3 cycle Our+worldwide flux estimate for NH3 (equivalent to - 7 Tg N yr- of NH3) is twice the flux of NH4 from biomass fIres estimated by A~eae et al and clearly substantiates their conjecture Indeed if we assume that the fluxes of NH4 and NH3 from biomass burning are additive the combined flux of -10 T~ N yr- 1 would be the most important input to the atmospheric NH3 cycle [cf Galbally 1985]1

The global flux of CH4 shown in Table III is in reasonable agreement with previous estimatesThe measurements of CH4 also reveal an interesting facet of fIre chemistry A regression of the CH4 emission factor on to the ratio of CO to C02 emission factors yields a linear

-5shy

89-2S3

Table III Mean values of EFxlEFffi for biomass burning (where EFx is the emission factor of trace gas s~ies x and CO the emission factor of CO) calculated from the data listed in Table nl Also shown are estimates of the global fluxes of various trace gases from biomass burning based on the EFxlEFCO ratios and estimates of worldwide CO emissions from biomass burning

Species EFxlEFCO Estimated Flux Estimated Contribution of from Biomass Biomass Burning to

Burning Worldwide (Tg yr-l)

Worldwide Flux of Species ()

03 006 plusmn OOS 48

NH3 001 ~ plusmn 0008 t oIl 8 SO

CH4 003 plusmn 00031OG1 24 -S

C3H6 0006 plusmn(J(Jj

0001 tilflL S

C2~ OOOS plusmn 0002 4

C3H8 0003 plusmn 0001 24

C2H2 0003 plusmn 0001 24

N-C4 0002 plusmn 0002 16

N20 0004 plusmn 0001 3 20

F12 00002 plusmn 00001 02 SO

(000008 plusmn OOOOOS )21 (006)2 (1s)2

NOx 007 plusmn 004 S6 40

1 The mean values of EFx IEFCO were obtained by nrst mtioing the values of EFx to EFCO for each of the fires listed in Table II and then averaging these seven ratios

2 A more conservative estimate obtained by eliminating results from the Lodi I fire (see text

correlation coefficient (r) of 092 significant at gt99 confidence level Clearly the ratio of CO to C02 in a plume is in a broad sense indicative of the oxidative capacity of the chemical enVIronment of a plume with low ratios suggesting limited oxygen (ie the combustion is fuel rich) Under such conditions one would expect enhanced production of CH4 (the most saturated hydrocarbon) due to anomalously high H2 levels A relatively extreme example of this phenomenon can be seen in the comparatively intense Battersby fire Plotted in Figure 1 are the COC02 and H2 concentrations as a function of 02 concentration in the plume from the Battersby

-6shy

89-253

flre at or near ground level The H2 will only be present in substantial quantities under at least mildly anaerobic conditions and tous supports the low 02 hypothesis Figure 1 confmns the utility of the COC02 ratio as a indicator of oxygen-limited combustion The correlation between CH4 and COC02 suggest that biomass flres are commonly oxygen limited A similar conclusion has been reached by Cofer et al [1985]19

An interesting sidelight of the data on H2 shown in Figure 1 is the very high H2 levels Indeed H2C02 ratios calculated from these data produce numbers as high as 001-004 These are similar to values obtained by Crutzen et al [1985]1 and support the view of these authors that biomass burning is an important source of atmosphere H2

lOo----------------~

x- - -x H2

CO

CO2 ~ I

0 I10-1 I

I I I I

I-

o CI

()

(3 10-2

()

10-3 ~ I

106

105

gtshyD

~ 1Q4 J

CI

103

Figure 1 Concentration ratio of COCO2 (circles) and H2 concentration (crosses) versus the concentration of 02 in the plume from the Battersby fire The measurements were made at or within~ m of the ground

10 Another interesting consequence of the fuelair mixture as revealed by the COC02 ratio is the

production of particulate smoke Many of the flres studied showed pronounced mcreases in particulate emission factors as the fire became increasingly anaerobic See for example Figure 2 which shows the particulate emission factor versus COC02 for the Battersby fire

-7shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2

Figure 2 Emission factor for particulates as a function of the COC02 concentration ratio in the plume from the Battersby fire

Our estimate for the worldwide flux of non-methane hydrocarbons (NMHC) from biomass burning shown in Table III (- 15 Tg yr1) is consistent with previous estimates [eg Crutzen et al 1985] of shy 30 Tg yr1 since only a fraction of the NMHCs are included in our flux estimates Our estimate for the N20 emission flux (- 2 Tg ~ yr-1) i~ also consistent wi~h previous e~ti~tes (eg 16 Tg N yr- 1) by Crutzen et a1 (loc Clt) ThlS confirms that blOmass burmng lS a significant source of atmospheric N20

The only sink for F12 that is generally considered in atmospheric budget calculations is loss by photo-disassociation in the stratosphere [National Research Council 198312deg However the global flux of F12 from biomass burning shown in Tfble III (- 02 Tg yr-l) is - 50 of the estimated yearly global emission of F12 (- 04 Tg yr- ) [National Research Council 1983]20 Since F12 cannot be produced by fires it must have been previously deposited onto the fuel bed and revolatilized in the fires Hence our results suggest that deposition of F12 may be important on the global scale contrary to current understanding of this issue However extrapolation of our average emission factor for F12 to global scales may not be warranted This is because the mean value of the F12CO ratio used in our calculation of the global flux of F12 from biomass burning is strongly influenced by the very high emissions of F12 that we measured from the Lodi I fire in the Los Angeles Basin (see Table II) The F12 emissions from Lodi I are five times greater than those from the Lodi II fire which was at the same location as Lodi 1 The reason for the high emissions of F12 from Lodi I is not clear although several speculations are possible For example the Lodi I fire in contrast to Lodi II took place in the relatively wet winter season and in fact occurred only six days after significant rainfall This rainfall could have produced high deposition of organic particulates in which the F12 could have been dissolved at relatively high levels Concentrations of various organic species in both aerosols and rain are known to be quite high in Los Angeles [Seinfeld 198921 Pankow et aI 1983]22 Furthermore particle scavenging bi hydrometeors is a significant pathway for organic aerosol removal [Pankow et aI 1983]2 However neither laboratory chemical data nor field data are available to permit a quantitative appraisal of the high F12 values measured in the smoke from Locli 1

It is also important to note that the F12 data from Lodi I do not show the same excellent internal consistency as those from Lodi II or the other fires For example the F12 emissions for Lodi I do not correlate with the CO emissions This casts some suspicion on the Lodi I data although there is no compelling reason to disregard them

-8shy

89-253

If the high emissions from Lodi I are not included in our calculations the reduced average F12 to CO emission ratio of 76 x 10-5 yields a global flux of - 006 Tg yr-l of F12 from biomass burning worldwide This is still quite significant (15 of the worldwide flux of FI2) Thus the deposition of F12 onto the earths surface could be the tropospheric sink postulated as a possible explanation for discrepancies in F12 atmospheric lifetime estimates [cf Cunnoly et al 1983]23

Our e~timate for the global flux of NO~ from biomass burning (56 Tg N yr ) converts to - 19 TgN yrl (based on our measuremen~s Which sh~w the NO to be -70 N~) Logan [1983] estImated a ~lobal flux of NOx from ~lOmass buomg f 12 g N yr-l WIth a possIble range of 4shy24 Tg N yr- Our flux eSUmate whIle compauble WIth Logans Wide range suggests that NOxfrom biomass burning may be more significant than previously assumed For example our estimate for the global flux of NOx from biomass burning is - 40 of total NOx emission to the atmosphere which makes it comparable to that generalg given for NOx emissions from fossil fuel combustion [cf Crutzen et al 197924 Logan 1983]

One possible explanation for the high emission factor for NO from biomass burning that we have estimated is the revolatization of NOx previously depositeJ on the vegetation and ground We have discussed this possibility in an earlier study [Hegg et al 1988a]5 The data presented here provide additional support for this hypotheris A regression of NOx emission factor onto F12 emission factor yields an intercept of 28 Tg yr a slope of 145 and a linear correlation coefficient of 08 significant at gt 95 confidence level (Figure 3) Because the source of F12 must be deposition of pollutants its correlation with NOx suggests that a substantial fraction of the emitted NOx is also due to deposition Indeed the regre$sion intercept which can be interpreted as the d emission factor for NOx after discounting revolatkation suggests that - 30 of the average NOx 7T emitted from the seven fires examined was duetOthe deposition of pollution For the fires in Southern California the percentage would clearly be much higher but is difficult to quantify because only two fires are available for regression analysis It is also noteworthy that a calculation of global NO~ flux from biomass buming using the intercept NOx eynssion factor ratioed to the average emissIon factor for CO shown in Table II yields - 8 Tg N yr which is more in line with earlier estimates [Crutzen et al 197924 Logan 1983]25 Clearly resuspension by biomass burning of NOx previously deposited from air pollution should be taken into account in global flux estimates

~ 12

90 10 z a o 8 u a o 6 () ltu 4 Z o U5 C) 2 ~ UJ o

0OO~01-0-0=-0-0-2--0- 0L=OO-=-3L-0--OO-O-5--0--00~1---O-OO~2--o--003-=-L-obulllOO-5-----o~01-------0-O~2---0~03----0-05

EMISSION FACTOR FOR F12 (g kgmiddot1)

Figure 3 NOx emission factor versus emissioFl factor for Fl2 for six of the the flres studied The regression line discussed in the text is shown (Note that the linear regression lines appears curved in this semi-log plot)

-9shy

89-253

Local Effects of Emissions from Biomass Burning

Most urban photochemical air pollution is generally attributed to emissions from combustion sources such as power plants and automobiles In particular hydrocarbon and NOx emissions from motor vehicles are generally considered to be the major sources of air pollution in Los Angeles [Finlayson-Pitts and Pitts 1985]26 However the relatively high emissions of NOx from biomass burning that we have estimated in this paper make it prudent to reassess this view

Emissions of CO and NOx are available for the South Coast Air Basin of California (which encompasses the counties of LOs Angeles Orange Riverside and San Bernadino) Relevant data are shown in Table IV Utilizing the data in Table II for NOx and CO emissions from the two Lodi flres in the Los Angeles Basin the ratio of the emission factor of Nq to CO is found to be - 0082 The product of this quantity with the emissions of CO from wilcurres shown in Table IV yield the estimates shown in the last column of Table IV for NO emissions from frres in the South Coast Air Basin Although our emission factors yield far more ~Ox from frres in the South Coast Air Basin than do the values used by the California Air Resources Board the estimates of total NOx emissions in the South Coast Air Basin are not signiflcantly perturbed by this revision since biomass burning in the South Coast Air Basin is small compared to emissions from motor vehicles However the seasonal and episodic nature of biomass burning could make emissions from this source important at various times of the year

Table IV CO and NOx emissions in the South Coast Air Basin of California Units are tons day-I

Geographical Unit Source NOx (This study)

Los Angeles County

Orange County

Riverside County

San Bernadino County

South Coast Air Basin

wild frres all sources


wild fires all sources



655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87

1 Private communication from V Bhargavar California Air Resources Board

-10shy

89-253

CONCLUSIONS

Measurements of the emissions of a number of trace gases from biomass fires in North America have been used to calculate emission factors for these gases While most of the emission factors are in reasonable agreement with previous estimates several of them are not In particular our estimates of the emissions of NH3 NOx and F12 are considerably higher than previous estimates The enhanced NO and F12 emissions were probably due to resuspension of previously deposited pollutants This suggests that re-evaluations of the global budgets of NH3 NO and F12 may be in order

)nother interesting facet of our emissions data is the suggestion that biomass fIres may to some extent be oxygen limited This leads for example to a more prolifIc production of saturated hydrocarbon species (eg CH4) than might be expected

Our data also suggests that NO~ ennssions from biomass burning in the South Coast Air Basin of California may be much greater than previously thought

Acknowled~ments We wish to thank D Ward and B Stocks for their help in the fIeld studies We also wish to thank G Agid and V Bhargava of the California Air Resources Board for providing the emissions data for the South Coast Air Basin This research was funded under Grant PSW-87-0020CA from the USDA Forest Service with funds supplied by the Defense Nuclear Agency

NOTE TO EDITORS

Under the new federal copyrllht law

publication rilhts to this paper are

retained by the author(s)

-11shy

89-253

REFERENCES

1 Crutzen P J A C Delany J Greenberg P Haagenson L Heidt R Lueb W Pollock W Seiler A Wartburg and P Zimmerman Tropospheric chemical composition measurements in Brazil during the dry season J AtolOs Chern 2 233 (1985)

2 Radke L F J L Stith D A Hegg and P V Hobbs Airborne studies of particles and gases from forest fIres J Air Poll Control Assoc 28 30 (1978)

3 Logan J A M F Prather S C Wofsy and M B McElroy Tropospheric chemistry a global perspective J Geophys Res 86 7210 (1981)

4 Hegg D A and P V Hobbs Measurements of gas-to-article conversion in the plumes from fIre coal-fIred electric power plants Atmos Enyiron li 99 (1980)

5 Hegg D A L F Radke P V Hobbs C A Brock and P J Riggan Nitrogen and sulfur emissions from the burning of forest products near large urban areas J Geopbys ~22 14701 (1988)

6 Rasmussen R A H H Westberg and M Holdren Need for standard referee GC methods in atmospheric hydrocarbon analyses J Chrom Sci 12 80 (1974)

7 Khalil M A K and R A Rasmussen Nitrous oxide trends and global mass balance over the last 3000 years Ann Glaciolill 73 (1988)

8 Radke L F D A Hegg J H Lyons C A Brock and P V Hobbs Airborne measurements on smokes from biomass burning in Aerosols and Climate Edited by P V Hobbs and M P McCormich A Deepak Publishing Co Hampton 1988 pp 411-422

9 Byram G M and K P Davis (Eds) Forest Fire Control and Use McGraw-Hill New York 1959 321 p

10 Hegg D A L F Radke P V Hobbs and P J Riggan Ammonia emissions from biomass burning Geophys Res Lett 1 335 (1988)

11 Mooney H A P M Vitousek and P A Watson Exchange of materials between terrestrial ecosystems and the atmosphere~ 218 926 (1987)

12 Andreae M 0 E V Browell M Garstang G L Gregory R C Harriss G L Hill D J Jacob M C Pereira G W Sachse A W Setzer P L Silva Dias R W Talbot A L Torres and S C Wofsy Biomass-burning emissions and associated haze layers over Amazonia J GeQphys Res 2l1509 (1988)

13 Radke L F Airborne observations of cloud microphysics modified by anthropogenic forcing In Proceedin~s of a Symposium on The Role of Clouds in Atmospheric ChemistrY and Global Climate American Meteorological Society pp 310-315 Anaheim California 29 Jan - 3 Feb 1989

14 Evans L F N K King P R Pockhaun and L T Stephens Ozone measurements in smoke from forest fires Environ Sci Technol B 75 (1974)

-12shy

89-253

15 Dismitriodes B and M Dodge (Eds) Proceedin~s of the Empirical Kinetic Modelin~ Approach CEKMA) validation WorkshCW EPA Report No 60019-83-014 August 1983

16 Hegg D A The importance of liquid-phase oxidation of S02 in the troposphere 1shyGeQphys Res 2Q 3773 (1985)

17 Logan J A Tropospheric ozone seasonal behavior trends and anthropogenic influence J GeQphys Res 2Q 10463 (1985)

18 Galbally L E The emission of nitrogen to the remote atmosphere background paper in Bio~eochemical Cyclin~ of Sulfur and Nitro~en in the Remote Atmosphere edited by J H Galloway R J Charlson M 0 Andreae and H Rodhe D Reidel Pub Heigham MA 1985 pp 27-53

19 Cofer W R J S Levine D I Sebacher E L Winstead P J Riggan B J Stocks J A Brass V G Ambrosia and P J Boston Trace gas emissions from Chaparral and boreal forest fires J Geophys Res 21 2255 (1989)

20 National Research Council Causes and Effects of Changes in Stratospheric Ozonemiddot Update National Academy Press Washington D c 1983

21 Seinfeld J H Urban air pollution state of the science ~ ill 745 (1989)

22 Pankow J F L M Isabelle W E Asher T J Kristensen and M E Peterson Organic compounds in Los Angeles and Portland rain identities concentrations and operative scavenging mechanisms in Precipitation Scavenging Dry Deposition and Resuspension Edited by H R Pruppacher R G Semonin and W G N Slinn Elsevier New York 1983 pp 403-415

23 Cunnold D M R G Prinn R A Rasmussen P G Simmonds F N Alyea C A Cardeling and A J Crawford The atmospheric lifetime experiment 4 results for CF2Cl2 based on three years data J Geophys Res 88 8401 (1983)

24 Crutzen P J L E Heidt J P Krasuee W H Pollock and W Seiler Biomass burning as a source of the atmospheric gases CO H2 N20 NO CH3CI and COS~~ 253 (1979)

25 Logan J A Nitrogen oxides in the troposphere global and regional budgets L Geophys Res ~ 10785 (1983)

26 Finlayson-Pitts B and J N Pitts Jr Atmospheric Chemistry John Wiley amp Sons New York 1985 pp 5-7

-13shy

89-253

ABS1RACf

Airborne measurements of thirteen trace gases from seven forest fIres in North America are used to determine their average emission factors The emission factors are then used to estimate the contributions of biomass burning to the worldwide fluxes of these gases The estimate for NHa (-7 Tg N yr-l) is about 50 of the global emissions of this gas Combined NH3 and NH4 emissions from biomass burning could be the most important component of the NH3 cycle N2U from biomass burning (- 2 Tg N yr-l) is also signifIcant worldwide The estimate ror NOxfrom biomass burning worldwide (- 19 Tg N yr1) which is greater than previous estimates is comparable to emissions from fossil fuel combustion The estimate of the ~lobal flux of F12 (CF2Cl2) from biomass burning based on the complete data set (- 02 Tg yr- ) is - 50 of the total global emission of F12 However this estimate is strongly influenced by a very high emission of F~ from a fIre in the Los Angeles Basin Disregarding this fIre yields a global flux of 006 Tg yr- (15 of total global emissions) The high emissions of NOx and F12 are due in whole or part to the resuspension of previously deposited pollutants Since this can be the only source ofF12 in the smoke from fIres deposition may be a signifIcant sink for F12

Our estimate for NOx emissions from biomass burning in the South Coast Air Basin of California are much greater than previous estimates

INTRODUCTION

Emissions of trace gases from biomass burning are known to be an important source of several trace gases (eg C02 CO and CH4) in the atmosphere [eg Crutzen et aI 1985]1 Also the emissions from fIres can have a marked effect on local and regional air quality [eg Radke et al 1978]2 However quantitative estimates of the contributions of such emissions to the global budgets of various trace species are diffIcult to make For example Logan et al [1981]3 estimated that CO emissions from global biomass burning ranged from 310 to 1250 Tg CO yr-l Estimates are even more uncertain for species that are more diffIcult to measure (eg NOx)

In this paper we present measurements of some trace gas emissions from seven biomass fIres in North America Emission factors are calculated for some trace gases and estimates are made of the signifIcance of such emissions on global and local scales

FIRES STUDIED AND MEASUREMENT TECHNIQUES

The locations times sizes and fuel types for the seven fIres examined in this study are listed in Table I The fIres encompass a wide range of woody biomass fuel types including the rarely studied chaparral of the Southwest United States

The measurements were obtained from the University of Washingtons C-131A research aircraft The aircraft instrumentation package and samfling procedures have been described by Hegg and Hobbs [1980]4 and Hegg et al [1988a] Many of the trace gases discussed (eg hydrocarbons N20) were analyzed by gas chromatography using the methodologies described by Rasmussen et al [1974]6 and Khalil and Rasmussen [1988f

-2shy

89-253








(Canada)



RESULTS

Emission Factors




-3shy

Tab

le II

A

vem

ge e

mis

sion

facl

Ors

(an

d st

anda

rd d

evia

tion

s) f

or v

ario

us tr

ace

gas

es fr

om s

even

bio

mas

s fi

res

in N

on

h A

mer

ica

Uni

ts a

re g

kg

-I

Fir

e C

O

CO

2 deg3

N

H3

CH

4 C

3

C2H

6 C

3Hg

C2

H2

N-C

411

N20

FIz

Y

NO

xll

Lod

i 1

74

plusmn 1

6 16

64 plusmn

44

14

plusmn 1

3 1

7 plusmn

08

2

Aplusmn

01

5 0

58 plusmn

O 0

5 0

35 plusmn

O1

2 0

21 plusmn

O1

2 0

32 plusmn

O0

5 0

11

plusmnO0

7 0

31 plusmn

O1

4 0

045

plusmnOO

W

89

plusmn3

5

Lod

i2

75plusmn1

4 16

5Oplusmn

31

019

plusmn 0

36

0

09

plusmn 0

04

36

plusmn0

25

O

A6plusmn

O0

3 0

55plusmnO

15

032plusmn

O1

2 0

21plusmnO

03

010

plusmnO

05

02

7plusmnO

31

0O

O9plusmn

O0

03

33

plusmn 0

8

Myr

tlel

10

6plusmn

20

1

62

6plusmn

39

-0

5 plusmn

02

2

0plusmn

09

3

0 plusmn

08

0

7plusmn

00

4

060

plusmnO

13

025

plusmnO

05

02

2plusmnO

04

002

plusmnO

04

000

25 plusmn

O0

015

254

plusmnO7

0 8

8 7

6

Fall

Cre

ek

Sil

ver

89

plusmn5

0

1637

plusmn 1

03

47

plusmn4

0

06plusmn

O 5

2

6plusmn

16

0

08 plusmn

00

1 0

56

plusmnO3

3 00

42 plusmn

Ol

3 0

19plusmn

O0

9 0

2plusmnO

1

027

plusmnO

39

00

081

plusmn 0

69

S1

U

I +0

I

Han

liman

8

2plusmn

36

16

64 plusmn

62

-05

plusmn 0

04

01

plusmn 0

07

19

plusmn0

5

058

plusmn 0

09

045

plusmnO

26

018

plusmnO

l3

03

1 plusmn

O3

5 0

02plusmn

O0

4 0

41 plusmn

O5

2 0

000

4 plusmnO

OO

O3

33

plusmn 2

3

90

7

Eagl

e 3

4plusmn

6

17

48

plusmn 1

1 6

5 plusmn

29

0

9 plusmn

02

0

25plusmnO

06

018

plusmnO

05

005

plusmnO

02

00

8 plusmnO

02

02plusmn

O0

8 0

16plusmn

O0

13

000

8plusmnO

003

7

2plusmn3

8

C~

Ban

ersb

y 17

5 plusmn

91

15

08

plusmn 1

61

-09

plusmn0

6

56

plusmn 1

7

09

plusmn 0

15

057

plusmnO

A5

027

plusmnO

12

033

plusmnO

06

007

plusmnO

06

105

plusmn1

33

1~~

F

2-

81yO~

Ove

rall

JrD

B

B3

3

8

2

lt o~

Ave

nge

E

mis

sion

9l

plusmn21

16

42plusmn3

7 3A

plusmn23

0

9Oplusmn0

A3

29

plusmn0

66

05

1plusmnO

14

047

plusmnO1

1 0

24plusmnO

06

024

plusmnO

04

010

plusmn0

05

028

plusmnO 0

5 0

01Iplusmn

O0

07

39

plusmn1

6

Fact

or

1 S

trai

ght c

hain

par

affi

n w

ith

carb

on n

umbe

r of

4

2 C

F 2Cl 2

00

~

3 N

O=

NO

+ N

02

I x

N

(J1

W

89-253









-5shy

89-2S3







CH4 003 plusmn 00031OG1 24 -S


0001 tilflL S


C3H8 0003 plusmn 0001 24

C2H2 0003 plusmn 0001 24

N-C4 0002 plusmn 0002 16

N20 0004 plusmn 0001 3 20

F12 00002 plusmn 00001 02 SO

(000008 plusmn OOOOOS )21 (006)2 (1s)2





-6shy

89-253



lOo----------------~

x- - -x H2

CO

CO2 ~ I

0 I10-1 I

I I I I

I-

o CI

()

(3 10-2

()

10-3 ~ I

106

105

gtshyD

~ 1Q4 J

CI

103




-7shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2





-8shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253








(Canada)



RESULTS

Emission Factors




-3shy

Tab

le II

A

vem

ge e

mis

sion

facl

Ors

(an

d st

anda

rd d

evia

tion

s) f

or v

ario

us tr

ace

gas

es fr

om s

even

bio

mas

s fi

res

in N

on

h A

mer

ica

Uni

ts a

re g

kg

-I

Fir

e C

O

CO

2 deg3

N

H3

CH

4 C

3

C2H

6 C

3Hg

C2

H2

N-C

411

N20

FIz

Y

NO

xll

Lod

i 1

74

plusmn 1

6 16

64 plusmn

44

14

plusmn 1

3 1

7 plusmn

08

2

Aplusmn

01

5 0

58 plusmn

O 0

5 0

35 plusmn

O1

2 0

21 plusmn

O1

2 0

32 plusmn

O0

5 0

11

plusmnO0

7 0

31 plusmn

O1

4 0

045

plusmnOO

W

89

plusmn3

5

Lod

i2

75plusmn1

4 16

5Oplusmn

31

019

plusmn 0

36

0

09

plusmn 0

04

36

plusmn0

25

O

A6plusmn

O0

3 0

55plusmnO

15

032plusmn

O1

2 0

21plusmnO

03

010

plusmnO

05

02

7plusmnO

31

0O

O9plusmn

O0

03

33

plusmn 0

8

Myr

tlel

10

6plusmn

20

1

62

6plusmn

39

-0

5 plusmn

02

2

0plusmn

09

3

0 plusmn

08

0

7plusmn

00

4

060

plusmnO

13

025

plusmnO

05

02

2plusmnO

04

002

plusmnO

04

000

25 plusmn

O0

015

254

plusmnO7

0 8

8 7

6

Fall

Cre

ek

Sil

ver

89

plusmn5

0

1637

plusmn 1

03

47

plusmn4

0

06plusmn

O 5

2

6plusmn

16

0

08 plusmn

00

1 0

56

plusmnO3

3 00

42 plusmn

Ol

3 0

19plusmn

O0

9 0

2plusmnO

1

027

plusmnO

39

00

081

plusmn 0

69

S1

U

I +0

I

Han

liman

8

2plusmn

36

16

64 plusmn

62

-05

plusmn 0

04

01

plusmn 0

07

19

plusmn0

5

058

plusmn 0

09

045

plusmnO

26

018

plusmnO

l3

03

1 plusmn

O3

5 0

02plusmn

O0

4 0

41 plusmn

O5

2 0

000

4 plusmnO

OO

O3

33

plusmn 2

3

90

7

Eagl

e 3

4plusmn

6

17

48

plusmn 1

1 6

5 plusmn

29

0

9 plusmn

02

0

25plusmnO

06

018

plusmnO

05

005

plusmnO

02

00

8 plusmnO

02

02plusmn

O0

8 0

16plusmn

O0

13

000

8plusmnO

003

7

2plusmn3

8

C~

Ban

ersb

y 17

5 plusmn

91

15

08

plusmn 1

61

-09

plusmn0

6

56

plusmn 1

7

09

plusmn 0

15

057

plusmnO

A5

027

plusmnO

12

033

plusmnO

06

007

plusmnO

06

105

plusmn1

33

1~~

F

2-

81yO~

Ove

rall

JrD

B

B3

3

8

2

lt o~

Ave

nge

E

mis

sion

9l

plusmn21

16

42plusmn3

7 3A

plusmn23

0

9Oplusmn0

A3

29

plusmn0

66

05

1plusmnO

14

047

plusmnO1

1 0

24plusmnO

06

024

plusmnO

04

010

plusmn0

05

028

plusmnO 0

5 0

01Iplusmn

O0

07

39

plusmn1

6

Fact

or

1 S

trai

ght c

hain

par

affi

n w

ith

carb

on n

umbe

r of

4

2 C

F 2Cl 2

00

~

3 N

O=

NO

+ N

02

I x

N

(J1

W

89-253









-5shy

89-2S3







CH4 003 plusmn 00031OG1 24 -S


0001 tilflL S


C3H8 0003 plusmn 0001 24

C2H2 0003 plusmn 0001 24

N-C4 0002 plusmn 0002 16

N20 0004 plusmn 0001 3 20

F12 00002 plusmn 00001 02 SO

(000008 plusmn OOOOOS )21 (006)2 (1s)2





-6shy

89-253



lOo----------------~

x- - -x H2

CO

CO2 ~ I

0 I10-1 I

I I I I

I-

o CI

()

(3 10-2

()

10-3 ~ I

106

105

gtshyD

~ 1Q4 J

CI

103




-7shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2





-8shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

Tab

le II

A

vem

ge e

mis

sion

facl

Ors

(an

d st

anda

rd d

evia

tion

s) f

or v

ario

us tr

ace

gas

es fr

om s

even

bio

mas

s fi

res

in N

on

h A

mer

ica

Uni

ts a

re g

kg

-I

Fir

e C

O

CO

2 deg3

N

H3

CH

4 C

3

C2H

6 C

3Hg

C2

H2

N-C

411

N20

FIz

Y

NO

xll

Lod

i 1

74

plusmn 1

6 16

64 plusmn

44

14

plusmn 1

3 1

7 plusmn

08

2

Aplusmn

01

5 0

58 plusmn

O 0

5 0

35 plusmn

O1

2 0

21 plusmn

O1

2 0

32 plusmn

O0

5 0

11

plusmnO0

7 0

31 plusmn

O1

4 0

045

plusmnOO

W

89

plusmn3

5

Lod

i2

75plusmn1

4 16

5Oplusmn

31

019

plusmn 0

36

0

09

plusmn 0

04

36

plusmn0

25

O

A6plusmn

O0

3 0

55plusmnO

15

032plusmn

O1

2 0

21plusmnO

03

010

plusmnO

05

02

7plusmnO

31

0O

O9plusmn

O0

03

33

plusmn 0

8

Myr

tlel

10

6plusmn

20

1

62

6plusmn

39

-0

5 plusmn

02

2

0plusmn

09

3

0 plusmn

08

0

7plusmn

00

4

060

plusmnO

13

025

plusmnO

05

02

2plusmnO

04

002

plusmnO

04

000

25 plusmn

O0

015

254

plusmnO7

0 8

8 7

6

Fall

Cre

ek

Sil

ver

89

plusmn5

0

1637

plusmn 1

03

47

plusmn4

0

06plusmn

O 5

2

6plusmn

16

0

08 plusmn

00

1 0

56

plusmnO3

3 00

42 plusmn

Ol

3 0

19plusmn

O0

9 0

2plusmnO

1

027

plusmnO

39

00

081

plusmn 0

69

S1

U

I +0

I

Han

liman

8

2plusmn

36

16

64 plusmn

62

-05

plusmn 0

04

01

plusmn 0

07

19

plusmn0

5

058

plusmn 0

09

045

plusmnO

26

018

plusmnO

l3

03

1 plusmn

O3

5 0

02plusmn

O0

4 0

41 plusmn

O5

2 0

000

4 plusmnO

OO

O3

33

plusmn 2

3

90

7

Eagl

e 3

4plusmn

6

17

48

plusmn 1

1 6

5 plusmn

29

0

9 plusmn

02

0

25plusmnO

06

018

plusmnO

05

005

plusmnO

02

00

8 plusmnO

02

02plusmn

O0

8 0

16plusmn

O0

13

000

8plusmnO

003

7

2plusmn3

8

C~

Ban

ersb

y 17

5 plusmn

91

15

08

plusmn 1

61

-09

plusmn0

6

56

plusmn 1

7

09

plusmn 0

15

057

plusmnO

A5

027

plusmnO

12

033

plusmnO

06

007

plusmnO

06

105

plusmn1

33

1~~

F

2-

81yO~

Ove

rall

JrD

B

B3

3

8

2

lt o~

Ave

nge

E

mis

sion

9l

plusmn21

16

42plusmn3

7 3A

plusmn23

0

9Oplusmn0

A3

29

plusmn0

66

05

1plusmnO

14

047

plusmnO1

1 0

24plusmnO

06

024

plusmnO

04

010

plusmn0

05

028

plusmnO 0

5 0

01Iplusmn

O0

07

39

plusmn1

6

Fact

or

1 S

trai

ght c

hain

par

affi

n w

ith

carb

on n

umbe

r of

4

2 C

F 2Cl 2

00

~

3 N

O=

NO

+ N

02

I x

N

(J1

W

89-253









-5shy

89-2S3







CH4 003 plusmn 00031OG1 24 -S


0001 tilflL S


C3H8 0003 plusmn 0001 24

C2H2 0003 plusmn 0001 24

N-C4 0002 plusmn 0002 16

N20 0004 plusmn 0001 3 20

F12 00002 plusmn 00001 02 SO

(000008 plusmn OOOOOS )21 (006)2 (1s)2





-6shy

89-253



lOo----------------~

x- - -x H2

CO

CO2 ~ I

0 I10-1 I

I I I I

I-

o CI

()

(3 10-2

()

10-3 ~ I

106

105

gtshyD

~ 1Q4 J

CI

103




-7shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2





-8shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253









-5shy

89-2S3







CH4 003 plusmn 00031OG1 24 -S


0001 tilflL S


C3H8 0003 plusmn 0001 24

C2H2 0003 plusmn 0001 24

N-C4 0002 plusmn 0002 16

N20 0004 plusmn 0001 3 20

F12 00002 plusmn 00001 02 SO

(000008 plusmn OOOOOS )21 (006)2 (1s)2





-6shy

89-253



lOo----------------~

x- - -x H2

CO

CO2 ~ I

0 I10-1 I

I I I I

I-

o CI

()

(3 10-2

()

10-3 ~ I

106

105

gtshyD

~ 1Q4 J

CI

103




-7shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2





-8shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-2S3







CH4 003 plusmn 00031OG1 24 -S


0001 tilflL S


C3H8 0003 plusmn 0001 24

C2H2 0003 plusmn 0001 24

N-C4 0002 plusmn 0002 16

N20 0004 plusmn 0001 3 20

F12 00002 plusmn 00001 02 SO

(000008 plusmn OOOOOS )21 (006)2 (1s)2





-6shy

89-253



lOo----------------~

x- - -x H2

CO

CO2 ~ I

0 I10-1 I

I I I I

I-

o CI

()

(3 10-2

()

10-3 ~ I

106

105

gtshyD

~ 1Q4 J

CI

103




-7shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2





-8shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253



lOo----------------~

x- - -x H2

CO

CO2 ~ I

0 I10-1 I

I I I I

I-

o CI

()

(3 10-2

()

10-3 ~ I

106

105

gtshyD

~ 1Q4 J

CI

103




-7shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2





-8shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253 shy

60~ 9

UJa 40 ~~

gt00laquo_Ushy

b Z laquoQ QC)

20

C)

~ 0 UJ 0 01

COCO2





-8shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253




~ 12





-9shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253






Los Angeles County

Orange County

Riverside County








655 33230

02 9880

267 33000

108 41200-1032

50530

10 6820

00 1720

04 500

01 810

1shy

15 9850

54

016

22

09

87


-10shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253

CONCLUSIONS





NOTE TO EDITORS




-11shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253

REFERENCES















-12shy

89-253













-13shy

89-253













-13shy

Documents

89-25.3 - FRAMES · Average emission factors for thirteen trace gases from the ftres are shown in Table II. The emission factors were derived using the carbon balance method [Radke