1. First global observation of organic compounds
from the IASI infrared sounder:
HCOOH and CH3OH
Federico Karagulian1, Lieven Clarisse1,
Ariane Razavi1, Cathy Clerbaux2, Pierre Coheur1,
Daniel Hurtmans1 ,Trissevgeni Stavrakou3 and
Jean-François Müller3
1Spectroscopie
de l’Atmosphere, Sevice de Chimie Quantique et de Photophysique,
Université Libre de Bruxelles, Brussels, Belgium
2UPMC Univ. Paris 06; Université Versailles St-Quentin; CNRS/INSU, LATMOS-IPSL, Paris, France.
3Belgian Institute for Space Aeronomy, Brussels, Belgium

2. IASI
IASI instrument and observing mode
(Infrared Atmospheric Sounding Interferometer)
MetOp: First European meteorological platform on
polar orbit (EPS system)
MetOP
IASI
Nadir looking FTS
• 12 km pixel x 4 @ nadir
• 120 spectra along the swath (±48.3° Scan
2400 km), each 50 km along the trace
Small ground pixel size
Global coverage twice
daily (morning and
evening orbits)
IASI
• Spectral coverage = 645-2760 cm-1
• Spectral resolution = 0.5 cm-1
• Radiometric noise ~ <0.1-0.2 K
Broad spectral
coverage without
gaps
Medium spectral resolution
High radiometric performances

3. IASI
IASI instrument and observing mode
Level 1 radiance spectrum
1.4x10
-5
1.2x10
1.0x10
-5
8.0x10
-6
4.0x10
-6
2
2
-6
6.0x10
CO
Radiance accuracy
within 0.5 K above
ocean
-5
-1
Radiance (W / cm sr cm )
SA/CNRS – ULB ULB
LATMOS/IPSL HNO3
CFC11, CFC12
2.0x10
O3
Illingworth et al., ACPD 2009
CH3OH
CO
HCOOH
CO2, N2O
Ts=275 K
N2O, CH4
16
H2 O, HOD
HOD
16
H2 O
-6
Thermal +
reflected solar
radiation
(daytime)
CH4
18
H2 O
0.0
800 1000 1200 1400 1600 1800 2000 2200 2400 2600
-1
Wavenumber (cm )

4. Trace gases
IASI contribution to atmospheric composition measurements
IASI species
10 Years
Year
Day
HCOOH
CH3OH
Hemispheric mixing:
~1-2 months
PBL mixing:
~few hours
CO
O3
HNO3
SO2
H2O + Iso
VOCs
NH3
hour.
HCOOH
CH3OH
Chemistry and sources
Month
Global mixing
~1 year
CFC11
N2O
CO2
CH4
OCS
Chemistry and transport
CO2
climate
CFC12
Sec.
IASI ACP special issue
With about 25 papers
HCOOH
CH3OH
Influence on the global
radiative forcing

5. SOURCES OF FORMIC ACID (HCOOH)
Use the IMAGESv2 global CTM* to simulate HCOOH
HCOOH lifetime: 7 days
Global annual HCOOH emission: 8.9 Tg/yr
Biogenic Emissions
MEGAN-ECMWF
(Muller et al. 2008)
Secondary
EDGARv3.3
Primary + secondary
Biogenic
72%
ISOPRENE
Terpenes
Ethene (C2H4)
Anthrop.
12%
Biomass
burning
16%
Primary + secondary
Ethyne C2H2
Hydroxacetone
Glycolaldehyde
Pyorogenic emissions
GFEDv2
(Van der Werf et al. 2006)
*Belgian Institute for Space Aeronomy (IASB-BIRA)

6. SOURCES OF methanol (CH3OH)
Use of IMAGESv2* to simulate CH3OH
CH3OH lifetime: 9 days
Global annual CH3OH emission: 204 Tg/yr
Biogenic Emissions
Biogenic Emissions
Primary
Plant
growth
65%
Plant
decay 11%
Primary
CH4 oxid. 12 %
VOCs oxid. 4%
Anthropogenic 5%
Fires 3%
*Belgian Institute for Space Aeronomy
(IASB-BIRA)

7. HCOOH observation in USA: retrieval with Atmosphit
1.00
(baseline); 1105
(target)
for the calculation of the Brightness
Temperature Difference (BTD)
cm-1
0.98
Trasmittance (a.u)
1103-1109cm-1
0.96
0.94
0.92
0.90
0.88
0.86
IASI Radiance spectrum
HCOOH
(reference)
1070
1080
Brightness Temperature (K)
HCOOH
2
-1
Radiance (W/m sr m )
1.0
0.8
0.7
H2O
0.6
0.5
0.4
2
-1
RMS = 2.746e-06 (W/m sr m )
2
[HCOOH] = 1.31e+16 molec/cm )
1103
1104
1105 1106 1107
-1
wavenumber (cm )
1108
1109
Averaging Kernels for total HCOOH column
-1
1090 1100 1110 1120
-1
wavenumber (cm )
-3
1.1x10
0.9
1105 cm
0.84
1130
1140
320
315
310
305
300
HCOOH x 10
295
290
285
1103
IASI spectrum in BT
Simulation of HCOOH
1104
H2O
1105
1106
1107
-1
wavenumber (cm )
1108
1109
Profiles
DOFland = 1.25
DOFocean = 1.5
Used a priori profile from IMAGESv2 model

8. Retrievals for HCOOH in the region (1103.74-1109.75 cm-1): USA
(1016 molec./cm2)
(Kelvin)
Countries
Slope(*)
Australia
0.8339
China
0.7049
USA
0.6187
East EU
0.7409
India
0.7301
Brazil
0.7719
Africa
0.7126
Mexico
0.6643
-2
HCOOH column (10 molec./cm )
 0-18 km  6 partial columns of 3 km thickness
 Good correlation between HCOOH column and BTD
2.0
Correlation = 0.892
16
1.5
1.0
0.5
-2
slope = 0.618e+16 (molec./cm )/K
R=0.8922
0.0
0.0
0.5
1.0
1.5
2.0
BTD (K)
2.5
3.0
3.5
(*)HCOOH
total column (1016 molec./cm2)/ BTD (K)

9. IMAGESv2 model 2008 (HCOOH: January 2008 - December 2008)
anthropogenic
biomass burning
biogenic
biomass burning
biogenic
A priori [HCOOH] total column = 2.9074e+15 molec./cm2

10. HCOOH Total Column (June 2008 - May 2009)
biogenic not seen
anthrop. in the model
anthrop. biogenic
biomass burning
HCOOH column (1014 molec./cm2)
biogenic
biomass burning
anthtop.
biomass burning
biogenic
anthrop.
biogenic
biomass burning

11. HCOOH Total Column (June 2008 - May 2009)
First background filtering: transport observed
biogenic not seen
anthrop. in the model
anthrop.
biogenic
anthrop.
biomass burning
biogenic
biogenic
biomass burning
no HCOOH observed above tropical forests
HCOOH column (1014 molec./cm2)
biogenic
biomass burning
anthtop.
biomass burning

12. Difference between IASI (filtered) and BIRA model (2008)
HCOOH column (1014 molec./cm2)
Mainly biogenic HCOOH emissions
over tropical forests

13. Correlation between HCOOH and CO emissions from fires in Africa
(1018 molec./cm2)
HCOOH column (10
16
2
molec./cm )
(1016 molec./cm2)
3.0
Savanna burning
Correlation factor = 0.9
Fires
(from MODIS)
2.5
2.0
1.5
CO emission
1.0
0.5
1.5
2.0
2.5
3.0
3.5
18
2
CO column (10 molec./cm )
HCOOH/CH3OH
emission
4.0
High correlation

14. Correlation between HCOOH and CH3OH; biogenic emissions?
(HCOOH) BTD (K)
(1018 molec./cm2)
(Kelvin)
(1016 molec./cm2)
1.6
Fires
 Good correlation between
HCOOH and CH3OH
correlation factor = 0.702
 Low correlation between CO
emission from fire and HCOOH/CH3OH
1.2
0.8
0.4
Not only biomass
burning
0.0
0.0
0.5
1.0
(CH3OH) BTD (K)
1.5
2.0
HCOOH and CH3OH might be correlated to
biogenic emissions (in addition to biomass burning)

15. CH3OH (September 2008 - July 2009)
anthropogenic
IASI Radiance spectrum (Mexico)
-5
1.0x10
20090508
-6
-1
radiance [W/m sr m ]
5.0x10
2
0.0
-6
-5.0x10
residue
residue - ch3oh
ch3oh simulated
-5
-1.0x10
-5
-1.5x10
-5
-2.0x10
1030
rms=2.650e-6
1040
1050
BT=1.072
1060
1070
1080
-1
wavenumber [cm ]
biomass burning
biogenic
Mainly plant growth
emissions from the
model IMAGESv2
CH4 oxidation

16. Correlation between vegetation and HCOOH emissions
cultivated
shrubs
desert
shrubs
shrubs
desert
herbaceous
shrubs
cultivated
trees
trees
shrubs
shrubs
cultivated
herbaceous
grass
shrubs
Not only biomass
burning
http://www.fao.or/

17. Correlation between vegetation in Africa and HCOOH
Biomass
burning
+
biogenic
desert
April 09
herbaceous
March 09
shrubs
trees
August 08
shrubs
shrubs
October 08
grass

18. Conclusions
 First global observations of HCOOH and CH3OH
(still at a qualitative level)
Sources
Transport
 Preliminary comparison with model IMAGESv2 shows
some correlations.
 Additional observation from IASI show:
 Not seen biogenic emissions above tropical forests
 Biogenic emissions above shrublands
 Anthropogenic emissions over the US and India
Outlook
 Optimization of the background filtering
 Optimization in the assignation of anthropogenic
and HCOOH/CH3OH biogenic emissions