SEARCH & VISTAS Special Studies
description
Transcript of SEARCH & VISTAS Special Studies
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SEARCH & VISTAS Special Studies
RPO National Technical Meeting
St. Louis, MO
November 5, 2003
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Outline
• SEARCH Overview• Data Quality for Continuous PM• Carbon Collaboration• NH3 Measurements• Biomass Emissions• In-Plume Oxidation Rates• SO4 Neutralization• Other
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SEARCH
SouthEastern
Aerosol
Research
and
CHaracterization
Study
Jefferson Street Site (JST)Atlanta, GA
Yorkville Site (YRK)Yorkville, GA
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Oak Grove
Centreville
Pensacola
Yorkville
Jefferson Street
North Birmingham
Gulfport
OLF #8
rural urban suburban
SEARCH Network
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SEARCH Measurements - Continuous
Category Observables
Temporal
ResolutionTrace Gases
O3, NO, NO2, HNO3, NHx, NOy, CO, SO2, CO2
1 min.
Fine Particles
Mass, BC, Bscat SO4
2-,NO3, NH4+
TC
<10 min. or
60 min.
Surface
Met.
T, RH, BP, WS, WD
SR, precip.
1 min.
Hg (2 sites) Hg(0), RGM, TPM 60 min.
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SEARCH Measurements - Discrete
Category Analyte(s)
Frequency(2000-2005)
PM2.5 Mass Daily
PM2.5 SO42-,NO3, NH4
+
OC, EC
Trace Elements
1/3
PMcoarse Mass 1/3
PMcoarse SO42-,NO3, NH4
+
Trace Elements
1/6
PMcoarse OC, EC 1/6 (2 sites)
Note: all measurements blank corrected
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Comparisons of Continuous and Discrete PM Measurements in
SEARCH
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SEARCH TEOM Configuration
• Nafion drier
• 30C
• Heavy insulation (thermal shock)
• Filter change every 3 days
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TEOM vs FRM
y = 1.0269x - 0.4609
R2 = 0.9637
0.00
10.00
20.00
30.00
40.00
50.00
0.00 10.00 20.00 30.00 40.00 50.00
Yorkville TEOM vs. FRM 2002
Median absolute difference = 0.84 ug/m3Median absolute % difference = 6.8No seasonality
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ARA Continuous SO4
• Harvard SO4 analyzer– Denuders to remove SO2 (carbonate) and
reduced S gases (C monolith)– Reduction of SO4 to SO2 on hot SS (850+C)– Automated zeroing every 90 minutes– 1-minute data acquisition
• Mean and s.d. each averaging interval
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ARA Continuous NO3/NH4
• 3-channel analyzer for NH4 and NO3
• NH4 via oxidation to NO on hot Pt
• NO3 via reduction to NO on Mo
• Remove gas phase species with acid/base denuders and C monolith
• Detection via NO-ozone CL
• 1-minute data acquisition
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Time Series of 24-Hr SO42-
0
2
4
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8
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12
14
8/2/
2002
8/3/
2002
8/4/
2002
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2002
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2002
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2002
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/200
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/200
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2002
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2002
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2002
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2002
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2002
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2002
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2002
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2002
Filter SO4 PILS SO4 ARA SO4
SO
4 (
ug
/m3)
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Time Series of Hourly SO42-
0
5
10
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20
25
8/23
/02
0:00
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/02
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0
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/02
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/02
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:00
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02 0
:00
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02 1
2:00
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02 0
:00
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02 1
2:00
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02 0
:00
ARA SO4 PILS SO4
SO
4 (u
g/m
3)
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Continuous vs. Filter SO42- at Yorkville
(using CE = 0.82)
cSO4 = 0.988*fSO4 - 0.05
R2 = 0.977
0
2
4
6
8
10
12
0 2 4 6 8 10 12
Filter SO4 (ug/m3)
Co
nti
nu
ou
s S
O4
(u
g/m
3)
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Hourly SO42- PILS vs. ARA Continuous
Atlanta, GA - August 2002(using CE = 0.86)
PILS = 1.003*ARA+ 0.027
R 2 = 0.9214
0
5
10
15
20
25
0 5 10 15 20 25
ARA SO4
PIL
S S
O4
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Time Series of 24-hr NH4+
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
8/17
/200
2
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/200
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2
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/200
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/200
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/200
2
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2002
9/2/
2002
9/3/
2002
9/4/
2002
9/5/
2002
9/6/
2002
9/7/
2002
9/8/
2002
Filter NH4 PILS NH4 ARA NMH4
NH
4 (u
g/m
3)
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Time Series of Hourly NH4+
0
1
2
3
4
5
8/23
/02
0:00
8/23
/02
12:0
0
8/24
/02
0:00
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/02
12:0
0
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/02
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/02
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0
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/02
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/02
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0
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02 0
:00
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:00
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:00
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:00
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2:00
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:00
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2:00
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02 0
:00
ARA NH4 PILS NH4
NH
4 (u
g/m
3)
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Scattergram of Hourly NH4+
PILS = 1.048*ARA- 0.44
R2 = 0.857
0
1
2
3
4
5
0 1 2 3 4 5
ARA NH4
PIL
S N
H4
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Time Series of 24-hr NO3-
0.0
0.3
0.5
0.8
1.0
8/17
/200
2
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/200
2
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/200
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/200
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2002
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2002
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2002
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2002
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2002
9/6/
2002
9/7/
2002
9/8/
2002
NO
3 (
ug
/m3
)
Filter NO3 PILS NO3 ARA NO3
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Time Series of Hourly NO3-
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
8/23
/02
0:00
8/23
/02
12:0
0
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/02
0:00
8/24
/02
12:0
0
8/25
/02
0:00
8/25
/02
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/02
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/02
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0
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/02
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/02
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0
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/02
0:00
8/29
/02
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0
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/02
0:00
8/30
/02
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0
8/31
/02
0:00
8/31
/02
12:0
0
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02 0
:00
9/1/
02 1
2:00
9/2/
02 0
:00
9/2/
02 1
2:00
9/3/
02 0
:00
9/3/
02 1
2:00
9/4/
02 0
:00
9/4/
02 1
2:00
9/5/
02 0
:00
9/5/
02 1
2:00
9/6/
02 0
:00
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02 1
2:00
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02 0
:00
9/7/
02 1
2:00
9/8/
02 0
:00
ARA NO3 PILS NO3
NO
3 (u
g/m
3)
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Continuous vs. Filter Summary24-Hr Averages (JST)
FilterMean Mean %E MAE MAPE
SO4 (30) 5.59 5.26 -5.8 0.51 9.9
NH4 (19) 1.89 1.70 -10.2 0.29 12.6
NO3 (23) 0.45 0.33 -26.8 0.15 27.7
FilterMean Mean %E MAE MAPE
SO4 (36) 5.82 6.10 4.8 0.43 8.5
NH4 (32) 2.15 2.10 -2.1 0.20 9.6
NO3 (35) 0.45 0.54 22.0 0.13 34.5
PILS
ARA
MAE = median abs. error; MAPE = median abs. % error
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Ongoing Comparison Work in VISTAS
• Millbrook Site– R&P 8400S (SO4) vs. HSPH SO4– R&P 8400N (NO3) vs. ARA NO3– R&P 5400 (EC) vsAethalometer (BC)– ARA NH4 vs. STN NH4
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SEARCH/ARIES Collaboration on Carbonaceous Aerosol
• Historical Samples (SEARCH/Improve/STN)– Composite Monthly or Seasonal Quartz Filters– Detailed Speciation (GC/MS)– CMB analysis for major sources
• Planned Samples (SEARCH 4 sites/VISTAS 5– Collect hi-vol samples 4 SEARCH sites, 5
VISTAS sites– Detailed Speciation/CMB and 14C for Selected
Events
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Primary Carbon Source Attribution Sample MatrixJanuary -December 2002
1= 4 one-month composite; one for each quarter6= 2 six-month composite; summer & winter3= 2 three-month composite; summer &winterD= 30 daily samples ; July’01 & Jan’02
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Sources of Primary OC in PM2.5
(F)(F/M ?)
(F)
(F)(M)(M)
(M)(Secondary F/M?)
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Primary
Secondary
Total
Modern
Speciation/CMB
Speciation, Models,
Difference
14C
Fossil
Speciation/CMB
Speciation, Models,
Difference
14C
Simplified Organic Carbon Source Matrix
Combination of CMB and C-14 data allows calculation of secondary OC by difference.
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OC Source MatrixAtlanta, GA – January
* 2000 Data: Zheng et al., ES&T, 2002.
Primary*
Secondary
Total#
Modern
64
<5
61 +/-5
Fossil
36
<5
39 +/-5
# from 14Cdata
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OC Source MatrixAtlanta, GA – July 2001
* Zheng et al. Source Apportionment of Fine Particles at Atlanta, GA, AAAR 2002
Primary*
Secondary
Total#
Modern
<5
>50
59 +/-5
Fossil
40*
<5
41 +/-5
# from 14C data
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SEARCH NH3 Measurements
Oak Grove
Centreville
Pensacola
Yorkville
Jefferson St.
N.Birmingham
Gulfport
OLF
rural urban suburban 24-hour denuder(1/3 day) all sites
Continuous at Yorkville (9/15/03)and Oak Grove(1/15/04)
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Total Reduced Nitrogen (NHx) Diagram
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Continuous NH3 vs Denuder NH3
24 Hour Samples
Continuous NH3 = 1.12 Denuder NH3 - 0.19R2 = 0.92
-1.0
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0
Denuder NH3, ug/m3
Con
tin
uou
s N
H3,
ug/
m3
Gaseous NH3 is deduced by subtracting particulate NH4 from NHx
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NH3 Time-Series9/12/03 – 9/30/03
Yorkville, GA SEARCH Site
-5.0
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
9/12/0
3
9/13/0
3
9/14/0
3
9/15/0
3
9/16/0
3
9/17/0
3
9/18/0
3
9/19/0
3
9/20/0
3
9/21/0
3
9/22/0
3
9/23/0
3
9/24/0
3
9/25/0
3
9/26/0
3
9/27/0
3
9/28/0
3
9/29/0
3
9/30/0
3
[NH
3], p
pbv
NH3
Gaseous NH3 is deduced by subtracting particulate NH4 from TRN
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HNO3, NH3, NH4NO3 Event9/24/03 – 9/27/03
Yorkville, GA SEARCH Site
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.09/
24/0
3 0:
00
9/24
/03
6:00
9/24
/03
12:0
0
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/03
18:0
0
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/03
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6:00
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/03
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12:0
0
9/27
/03
18:0
0
[HN
O3]
ppb
v [N
O3]
ug/
m3,
[NH
4] u
g/m
3
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
45.0
50.0
[NH
3], p
pbv
HNO3 NH4 NO3 NH3
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1-hour NHx vs. Wind Direction
0.0
10.0
20.0
30.0
40.0
50.0
60.0
0 45 90 135 180 225 270 315 360
Wind Direction, Degrees
[NH
3 +
NH
4], p
pbv
NH3 + NH4
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1.8 km
2.3 km4.5 km
The Smoking Chicken
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http://www.firedetect.ssd.nesdis.noaa.gov/index.htm
HMS Fire and Smoke Summary for 2345 10/21/03
Emissions from Biomass Burning
Oak Grove
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0
90
180
270
360
10/21/03 0:00 10/21/03 4:00 10/21/03 8:00 10/21/03 12:00 10/21/03 16:00 10/21/03 20:00
WD
R (
de
g.)
0.0E+00
2.5E-05
5.0E-05
7.5E-05
1.0E-04
Bs
p (
m**
-1)
WDR Bsp
Bsp
(m
-1)
WD and Bsp for Oak Grove – 10/21/03
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100
200
300
400
500
600
10/21/03 0:00 10/21/03 4:00 10/21/03 8:00 10/21/03 12:00 10/21/03 16:00 10/21/03 20:00
CO
(p
pb
)
0
3
6
9
12
15
NO
y (
pp
b)
CO NOy
CO and NOy at Oak Grove – 10/21/03
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NOy = 0.0154*CO - 2.66
R2 = 0.967
2.0
3.0
4.0
5.0
6.0
300 350 400 450 500 550 600
CO (ppb)
NO
y (
pp
b)
NOy vs. CO Oak Grove Event – 10/21/03
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FUEL NOy (as NO) SO2 PM2.5 TC* BC*
Savannah/Grassland 60 5.4 83 57 3.1
Trop. Forest 15 5.5 88 64 6.4
non-Trop. Forest 28 9 121 78 5.2
Biofuels 27 3.5 92 51 7.6
Ag. Residues 27 4.3 42 36 7.5
This Study (Fires) 28+/-14 5.0 +/-2/7 195 +/- 54 63 +/- 14 15 +/- 6.1
This Study (Urban)# 147 +/-10 n.d. 33 +/- 8 9.6 +/- 2.1 n.d.
Andreae and Merlet. Global Geochem Cyclec 15(4):955-966. 2001. (A&M)* A&M TC and BC based on TSP# Based on Jefferson Street, Atlanta, GA SEARCH data
ER (g/kg CO)
Comparison of ERs with Literature Values
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Field Observations of SO2 Oxidation Rates in Coal Fired
Power Plant Plumes
E. S. Edgerton, B. E. Hartsell, C. J. Waid, ARA, Inc.
J. J. Jansen, Southern Company
D. Alan Hansen, EPRI
AAAR 2003
Anaheim, CA
October 22, 2003
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SO2 and SO4 8/20/02 Event
0
10
20
30
40
50
60
70
8/20/2002 0:00 8/20/2002 4:00 8/20/2002 8:00 8/20/2002 12:00 8/20/2002 16:00 8/20/2002 20:00
SO
2 (
pp
b)
0
1
2
3
4
5
SO
4 (
pp
b)
SO2 SO4 ZERO
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0
0.5
1
1.5
2
2.5
3
5:00 7:00 9:00 11:00 13:00 15:00 17:00 19:00
Midpoint
Co
nve
rsio
n R
ate
(%)
Fall-Winter Spring-Summer
Daytime Pattern of Observed Oxidation (n = 28)
1
1 4
2
2
63
43
3
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0
3
6
9
12
15
8/16/010:00
8/16/012:00
8/16/014:00
8/16/016:00
8/16/018:00
8/16/0110:00
8/16/0112:00
8/16/0114:00
8/16/0116:00
8/16/0118:00
8/16/0120:00
8/16/0122:00
SO
4, N
O3,
NH
4 (u
g/m
3)
0
10
20
30
40
50
PM
2.5
(ug
/m3)
SO4 NO3 NH4 PM2.5
Continuous PM at Jefferson StreetAugust 16, 2001
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0
3
6
9
12
15
8/16/010:00
8/16/012:00
8/16/014:00
8/16/016:00
8/16/018:00
8/16/0110:00
8/16/0112:00
8/16/0114:00
8/16/0116:00
8/16/0118:00
8/16/0120:00
8/16/0122:00
SO
4, N
H4
(ug
/m3)
0.0
0.5
1.0
1.5
2.0
2.5
Mo
lar
Rat
io
SO4 NH4 Ratio
Ammonium sulfate
Ammonium bisulfate
Sulfuric acid
SO4, xsNH4 and Molar Ratio
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0
2
4
6
8
10
12
14
8/16/01 0:00 8/16/01 4:00 8/16/01 8:00 8/16/01 12:00 8/16/01 16:00 8/16/01 20:00
SO
4 (
ug
/m3
)
0.0
0.5
1.0
1.5
2.0
2.5
ad
jRa
tio
SO4 adjRatio
Background adjusted Molar Ratio
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SEARCH/VISTAS Collaborationon
Characterization of Meteorology and its Relationships to Fine Particle Mass and
Visibility in the VISTAS Region
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Summary• SEARCH network will provide comprehensive PM/trace gas data
through 2005• Filter data needed to characterize continuous PM technologies
– Data adjustments– Data uncertainty
• Carbon speciation work underway (primary vs.secondary, Modern vs. Fossil)
• NH3 measurements begun in the SE– Primary species: high and variable near sources, expect lower and less
variable near sinks• Combination of continuous PM and Gas measurements shows
promise– SO4 neutralization variability– Contributions from biomass burning– gas/particle conversion