Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Fire Plume RiseWRAP (FEJF) Method vs. SMOKE Briggs
(SB) Method
Mohammad Omary, Gail TonnesenWRAP Regional Modeling CenterUniversity of California Riverside
Zac AdelmanCarolina Environmental Program
University of North Carolina
Fire Emissions Joint Forum Meeting, October 17-18, 2006, Spokane, WA
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Fire Plume Rise Modeling Project Status
• Today’s Presentation– Project Objectives– Plume Rise Modeling Methods– Fire Events Modeled– Results– Summary
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Acknowledgments
• Tom Moore and FEJF – project design• Air Sciences - Emissions Inventory
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Fire Plume Rise Modeling Project Objectives
Compare the plume rise and the vertical emissions distribution for fires, using to methods:
1. The FEJF Approach2. The SMOKE-Briggs Approach
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Model vertical layer structure
• CMAQ has 19 vertical layers:– Layer 1: 0 - 36 m– Layer 2-5: 36 - 220 m– Layer 6-10: 220 - 753 m – Layer 11-14: 753 - 1828 m– Layer 15-16: 1828 - 3448 m– Layer 17-19: 3448 - 14,662 m
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Plume Tophour = (BEhour)2 * (BEsize)2 * Ptopmax
Plume Bottomhour = (BEhour)2 * (BEsize)2 * Pbotmax
Layer1 Fractionhour = 1 – (BEhour * BEsize)
BEsize = fire size-dependent buoyancy efficiency Behour = hourly buoyancy efficiency Pbotmax = maximum height of the plume bottomPtopmax = maximum height of the plume top
BEsize, Ptopmax Pbotmax, and BEhour are provided in the FEJF Phase II fire report (Air Sciences, Inc., 2006).
1. FEJF ApproachPlume Rise Modeling Methods
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Plume Buoyancy Efficiency, F (m4/s3), as follows.F = Q * 0.00000258Q = Heat Flux (btu/day),
Buoyant Efficiency (BEsize)BEsize = 0.0703 * ln(acres) + 0.03
Smoldering Fraction (Sfract)Sfract = 1 – BE size
NOTE: possible bug in implementing smoldering fraction in SMOKE. We expect a larger fraction of emissions in layer 1 in SB.
2. SMOKE-Briggs Approach (SB)
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Heat Flux from FEPS
• Fire Emissions Productions Simulator (FEPS) was used to determine heat flux:– FEPS was developed by Anderson et al.
http://www.fs.fed.us/pnw/fera/feps/– User specifies the fire name, location, start date, end date,
size, fuel type and other properties.– FEPS calculates the hourly emissions and heat release.– Uncertainty in specifying fire variables in FEPS might
affect heat release estimate.– Not available in batch mode so difficult to use FEPS in SB.
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Fire Type State Date
Fire Size(Acres)
Daily Emissions (tons/day)Heat Flux (btu/day)CO PM2.5 NOx VOC
WFU1 CO July 14 850 3382.6 282.08 72.57 159.18 82,530,000,000
RX2 AZ Nov. 07 2577 3988.1 332.58 85.56 187.68 268,320,000,000
WF3 AZ June 30 9860 19804.3 1651.5 424.9 931.97 1,036,600,000,000
RX OR Sep. 24 1000 173.4 14.46 3.72 8.16 300,030,000
WF OR Aug. 03 7885 25,293.8 2,109.3 542.6 1,190.3 2,237,008,255,600
1WFU= wildland fire use 2RX=prescribed fire 3WF=wildfire
Fire Events
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
0
1000
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3000
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6000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Hei
ght (
m)
0
0.2
0.4
0.6
0.8
1
1.2
Emis
. Fra
c. in
Lay
er 1
PBOTPTOPLAY1F
FEJF fire CharacteristicsOregon Prescribed Fire
PBOT = Plume BottomPTOP = Plume TopLAY1F = Emissions fraction in Layer 1
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
0
1000
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7000
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
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0
0.2
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0.6
0.8
1
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Emis
. Fra
c. in
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er 1
PBOTPTOPLAY1F
FEJF fire CharacteristicsOregon Wild Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Hourly Emissions per LayerColorado Wild Fire
1 3 5 7 911 13 15 17 19 21 23 L1 L4 L7 L1
0 L13 L1
6
0
100
200
300
400
500
600
CO
Ton
s/h
TimeLayer
FEJF Plume riseL1L2L3L4L5L6L7L8L9L10L11L12L13L14L15L16L17L18
Tot
1 3 5 7 911 13 15 17 19 21 23 L1
L4
L7 L10
0
100
200
300
400
500
600
Time
Layer
SB Plume Rise
L1L2L3L4L5L6L7L8L9L10L11L12
Tot
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
FEJF Profile
050
100150200250300350400450500550600
1 3 5 7 9 11 13 15 17 19 21 23
Time (h)
Tons
/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L18L17L16L15L14L13L12L11L10L9L8L7L6L5L4L3L2L1Max LHSB Profile
050
100150200250300350400450500550600
1 3 5 7 9 11 13 15 17 19 21 23
Time (h)
Ton
s/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L12L11L10L9L8L7L6L5L4L3L2L1Max LH
Hourly Emissions DistributionColorado Wild Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
1 3 5 7 911 13 15 17 19 21 23
0
100
200
300
400
500
600
700
CO
Ton
s/h
TimeLayer
FEJF Plume riseL1L2L3L4L5L6L7L8L9L10L11L12L13L14L15L16L17L18
Tot
1 3 5 7 911 13 15 17 19 21 23 L1 L2 L3 L4 L5 L6 L7 L8 L9 L1
0L1
1To
t
0
100
200
300
400
500
600
700
CO
Ton
s/h
Time
Layer
SB Plume rise
L1L2L3L4L5L6L7L8L9L10L11
Tot
Hourly Emissions per LayerArizona Prescribed Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
FEJF Profile
050
100150200250300350400450500550600650700
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Ton
s/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L18L17L16L15L14L13L12L11L10L9L8L7L6L5L4L3L2L1Max LH
SB Profile
050
100150200250300350400450500550600650700
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Tons
/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L11
L10
L9
L8
L7
L6
L5
L4
L3
L2
L1
Max LH
Hourly Emissions DistributionArizona Prescribed Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
0
500
1000
1500
2000
2500
3000
CO
Ton
s/h
Time
Layer
FEJF Plume rise
L1L2L3L4L5L6L7L8L9L10L11L12L13L14L15L16L17L18
Tot
0
500
1000
1500
2000
2500
3000
3500
CO
Ton
s/h
Time
Layer
SB Plume rise L1L2L3L4L5L6L7L8L9L10L11L12L13L14L15
Tot
Hourly Emissions per LayerArizona Wild Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
FEJF Profile
0
500
1000
1500
2000
2500
3000
3500
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Tons
/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L18L17L16L15L14L13L12L11L10L9L8L7L6L5L4L3L2L1Max LH
SB Profile
0
500
1000
1500
2000
2500
3000
3500
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Ton
s/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L15L14L13L12L11L10L9L8L7L6L5L4L3L2L1Max LH
Hourly Emissions DistributionArizona Wild Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
0
5
10
15
20
25
30
CO
Ton
s/h
Time Layer
FEJF Plume riseL1L2L3L4L5L6L4L8L9L10L11L12L13L14L15L16L17
Tot
1 3 5 7 9 11 1315
17 1921
23
0
5
10
15
20
25
30
CO
Ton
s/h
TimeLayer
SB Plume rise
L1L2L3L4
Tot
Hourly Emissions per LayerOregon Prescribed Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
FEJF Profile
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Tons
/h
040080012001600200024002800320036004000440048005200
Max
Lay
er H
iegh
t (m
)
L17L16L15L14L13L12L11L10L9L8L7L6L5L4L3L2L1Max LH
SB Profile
0
5
10
15
20
25
30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Ton
s/h
0
400
800
1200
1600
2000
2400
2800
3200
3600
4000
4400
4800
5200
Max
Lay
er H
iegh
t (m
) L4
L3
L2
L1
Max LH
Hourly Emissions DistributionOregon Prescribed Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
0
500
1000
1500
2000
2500
3000
3500
4000
4500
CO
Ton
s/h
TimeLayer
FEJF Plume rise
L1L2L3L4L5L6L7L8L9L10L11L12L13L14L15L16L17L18
Tot
1 3 5 7 9 11 13 15 17 19 21 23
0
500
1000
1500
2000
2500
3000
3500
4000
4500
CO
Ton
s/h
TimeLayer
SB Plume rise L1L2L3L4L5L6L7L8L9L10L11L12L13L14L15
Tot
Hourly Emissions per LayerOregon Wild Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
FEJF Sky Profile
0
400
800
1200
1600
2000
2400
2800
3200
3600
4000
4400
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Tons
/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L18L17L16L15L14L13L12L11L10L9L8L7L6L5L4L3L2L1Max LH
SB Profile
0
500
1000
1500
2000
2500
3000
3500
4000
4500
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Time (h)
Ton
s/h
0500100015002000250030003500400045005000550060006500700075008000
Max
Lay
er H
iegh
t (m
)
L15L14L13L12L11L10L9L8L7L6L5L4L3L2L1Max LH
Hourly Emissions DistributionOregon Wild Fire
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
0
0.1
0.2
0.3
0.4
0.5
0.6
daily
frac
tion
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
CO
_FEJ
F
CO
_SB
AZ_
FEJF
_WF
AZ_
SB_W
F
AZ_
FEJF
_RX
AZ_
SB_R
X
OR
_FEJ
F_W
F
OR
_SB
_WF
OR
_FEJ
F_R
X
OR
_SB
_RX
layer
CO_FEJFCO_SBAZ_FEJF_WFAZ_SB_WFAZ_FEJF_RXAZ_SB_RXOR_FEJF_WFOR_SB_WFOR_FEJF_RXOR_SB_RX
Daily Emissions Fractions per Layer
CO FEJF: 45% in surface layer, 45% above 2462 m.
CO SB: most emission between 200 - 1000 m.
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Results
1. The FEJF approach places a large fraction of the emissions in the surface layer, and the plume with the remaining emissions are consistently located at higher layers compared to the SB approach.
2. The plume bottom in FEJF depend on the fire size. It can be as high as several thousand meters above the first layer. In SB the plume bottom is always above the first layer.
3. On daily basis, most of the emissions are in the first layer in FEJF, while in SB most of the emissions in the mid to upper layers.
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Conclusions• The SB approach seems unrealistic since smoldering
emissions should be located in the first layer.• Since emissions occur during the day time when the boundary
layer tends to be well mixed, model results might be insensitive to the vertical location of emissions within the boundary layer.– To the extent that the FEJF approach locates emissions above the
boundary layer, it might have smaller near field impact and greater long range transport.
– If fires occur at times when the boundary is shallow or poorly mixed, the FEJF approach might have a greater near field impact and less long range transport.
Center for Environmental Research and Technology/Environmental Modeling
University of California at Riverside
Conclusions (2)• Air quality modeling using CMAQ or CAMx is needed to
determine of the two approaches would have significantly different air quality impacts, however, the current approach using FEPS is not feasible to model a large number of events.
• Because the differences in near field versus long range transport might depend on the meteorology conditions, it would be necessary to model a large variety of conditions to determine if the choice of FEPS or SB results in consistently different visibility impacts.
• SB approach would have greater near field impacts than FEJF if SMOKE is modified to locate a larger smoldering fraction in layer 1.