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biogenic, pryogenic, anthropogenic
pryogenicanthropogenic
biogenicanthropogenic
pryogenicpyrogenicanthropogenic
biogenicanthropogenic
Thom
as
Kuro
su, H
arv
ard
-Sm
ithso
nia
n
HCHO August 2006Ozone Monitoring Experiment
Using space-based measurements of formaldehyde to learn about BVOC
distributionsPaul Palmer, University of Edinburgh
Environmental factors:• temperature• solar irradiance• leaf area index• leaf age
July2003
MEGAN Isoprene Emission Inventory
Global Ozone Monitoring Experiment (GOME) &the Ozone Monitoring Instrument (OMI)
• GOME (European), OMI (Finnish/USA) are nadir SBUV instruments• Ground pixel (nadir): 320 x 40 km2 (GOME), 13 x 24 km2 (OMI)• 10.30 desc (GOME), 13.45 asc (OMI) cross-equator time • GOME: 3 viewing angles global coverage within 3 days• OMI: 60 across-track pixels daily global coverage• O3, NO2, BrO, OClO, SO2, HCHO, H2O, cloud properties
Launched in 2004
GOME
GOME HCHO columns
July 2001
[1016 molec cm-
2]
0 1 20.5
1.5
2.5
Biogenic emissions
Biomass burning
* Columns fitted: 337-356nm * Fitting uncertainty < continental signals
Data: c/o Chance et al
– fractionally cloudy pixels (>40%) removed
Relating HCHO Columns to VOC Emissions
VOC HCHOhours
OH
hours
h, OH
Local linear relationship between HCHO and E
kHCHO
EVOC = (kVOCYVOCHCHO)HCHO
___________
VOC source
Distance downwind
HCHO Isoprene
-pinenepropane
100 km
EVOC: HCHO from GEOS-CHEM CTM and MEGAN isoprene emission model
Palmer et al, JGR, 2003.
Net
MCM HCHO yield calculationsC
um
ula
tive H
CH
O y
ield
[p
er
C]
0 2 4 6 8 10 12 14 16 18 20 220.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
HC
HO
YIE
LD
PE
R C
RE
AC
TE
D
DAYS
NOX= 1 PPB NOX= 100 PPT
pinene
( pinene similar)DAYS
0.4
0 20 40 60 80 100 120 1400.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55C
umm
ula
tive
HC
HO
Yie
ld fr
om
iso
pren
e o
xid
atio
n (p
er C
)
TIME (HOURS)
NOX = 0.1 PPB
NOX =1 PPB
Figure 18. Formation of HCHO from isoprene. Vertical lines denote midnight of each day
Isoprene
HOURS
0.5NOx = 1 ppb
NOx = 0.1 ppb
Parameterization (1ST-order decay) of HCHO production from monoterpenes in global 3-D CTM
Higher CH3COCH3 yield from monoterpene oxidation delayed (and smeared) HCHO production
Palmer et al, JGR, 2006.
C5H8+OH(i) RO2+NOHCHO, MVK, MACR
(ii) RO2+HO2ROOH
ROOH recycle RO and RO2
GOME Isoprene Emissions: 1996-2001May Jun Jul Aug Sep
1996
1997
1998
1999
2000
2001
[1012 molecules cm-2s-1]0 5 10
Palm
er
et
al, JG
R,
2006.
Surface temperature explains 80% of GOME-observed variation in HCHO
NCEP Surface Temperature [K]
GO
ME Iso
pre
ne E
mis
sions
[1
012 a
tom
s C
cm
-2s-
1] G98 fitted to
GOME data
G98 Modeled curves
Time to revise model parameterizations of isoprene emissions?
Palm
er
et
al, JG
R,
2006.
Tropical ecosystems represent 75% of biogenic NMVOC emissions
What drives observed variability of tropical BVOC emissions?
Sla
nt
Colu
mn H
CH
O [
10
16 m
ole
c cm
-2]
Sep 1997
Nov 1997
19971998199920002001
X = Active Fire (ATSR)
Mon
thly
ATS
R F
irecou
nts
Day of Year
Significant pyrogenic HCHO source over tropicsGood: Additional trace gas measurement of biomass burning; effect can be identified largely by firecounts (see below)
Bad: Observed HCHO a mixture of biogenic and pyrogenic – difficult to separate without better temporal and spatial resolution
GOME
HCHO and Isoprene over the Amazon
In situ isoprene 2002
Tro
stdorf e
t al,
200
4
19971998199920002001
GOME
ATSR Firecounts used to remove HCHO from fires
em
issio
n r
ate
(C
)(µ
g g
-1 h
-1)
PA
R(µ
mol m
-2 s
-1)
assim
ilati
on
(C
)(m
g g
-1 h
-1)
0
1
2
3
4
5
6
limonene myrcene b-pinene a-pinene sabinene
500
1000
1500
00:0006:00
12:0018:00
00:0006:00
12:0018:00
00:00
0
2
4
local time [hh:mm]
10
20
30
40
tem
pera
ture
[°C
]
0
2
4 G
93
for
isop
.[s
um
of
mon
ote
rpen
es]
tran
sp
irati
on
(mm
ol m
-2 s
-1)
monoterpene emission of Apeiba tibourbou
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
00:00 02:24 04:48 07:12 09:36 12:00 14:24 16:48 19:12 21:36 00:00
Time bin midpoint
Co
nce
ntr
atio
n (
pp
b)
0
1
2
3
4
5
6
00:00 02:24 04:48 07:12 09:36 12:00 14:24 16:48 19:12 21:36 00:00
Time bin midpoint
Co
nce
ntr
atio
n (
pp
b)
0
0.5
1
1.5
2
2.5
3
3.5
00:00 02:24 04:48 07:12 09:36 12:00 14:24 16:48 19:12 21:36 00:00
Time bin midpoint
Co
nce
ntr
atio
n (
pp
b)
Isoprene
Limonene
Beta-pinene
[pp
b]
Time of DayC/o J. Kesselmeier
C/o J. Saxton A. Lewis
Amazon
AfricaCan isoprene explain the observed magnitude and variance of HCHO columns over the tropics?
May Jun Jul
Aug Sep Oct
OMI gives a better chance of estimating African BVOCs
OMI Data c/o Thomas Kurosu; horizontal resolution O(10x25 km2)
Isoprene concentrations during AMMA July 2006 measured by the Bae146 aircraft; MODIS tree cover overlaid
Isoprene data c/o Jim Hopkins and Ally Lewis, U. York
Jul
OMI
-2 -1 0 1 2 3 4 5 69
10
11
12
13
14
1.000
1.951
3.807
7.429
14.50
28.28
55.19
107.7
210.1
410.0
800.0
[ppt]
-2 -1 0 1 2 3 4 5 69
10
11
12
13
14
1.000
1.951
3.807
7.429
14.50
28.28
55.19
107.7
210.1
410.0
800.0
ATSR Firecounts
Jul
40
45
50
55
60
65
70
- 60 - 50 - 40 - 30 - 20 - 10 0 10
“Normal” airmass flow
44
46
48
50
52
54
56
- 20 - 15 - 10 - 5 0 5 10
Stagnant airmass flow
0
200
400
600
800
1000
1200
1400
27-Jul
29-Jul
31-Jul
2-Aug
4-Aug
6-Aug
8-Aug
10-Aug
12-Aug
14-Aug
16-Aug
18-Aug
20-Aug
22-Aug
24-Aug
26-Aug
28-Aug
30-Aug
0
5
10
15
20
25
30
35
40
Tem
pera
ture
(C
)
Isop
ren
e (
pp
t)
Estimated up to 700 extra deaths attributable to air pollution (O3 and PM10) in UK during this period
O3 > 100 ppb on 6 consecutive days
2pm, 6th Aug, 2003
Compiled from UK ozone network data
Isoprene c/o Ally Lewis
An increasing role for BVOCs in UK air quality?
Stewart et al, 2003Isoprene
MonoterpenesBVOC fluxes for a “hot, sunny” day
1016 [molec cm-
2]
OMI HCHO
2<0.3
Bottom-up emission inventory
“Expect harmful levels of ozone and PM2.5 over the next couple of days; please keep small children and animals inside. Transatlantic pollution represents 20% of today’s UK surface ozone.”
2010
Satellite observations test bottom-up emission inventories used for air quality: an important step toward regional chemical weather forecasting
Final Comments
Proper interpretation of HCHO requires an integrated approach, i.e., including surface data, lab data
Interpreting space-based HCHO data is still in its infancy – new instruments bring better resolution but also new challenges
With the frequency of European heatwaves projected to increase the role of BVOCs in future UK air quality must be better quantified