MOPITT Validation by groundbased grating spectrometer measurements: The importance of the apriori pr

1
CO TOTAL COLUMN MEASUREMENTS IN THE NORTHERN
HEMISPHERE FROM THE GROUND AND FROM SPACE
EFFECTS OF FOREST FIRES IN 2002 AND 2003
(IGAC-2004, Christchurch, New Zealand)
Leonid Yurganov (1) P. Duchatelet (2) A.
Dzhola (3) D. Edwards (4) F. Hase (5) I.
Kramer (5) E. Mahieu (2) J. Mellqvist (6)
J. Notholt (7) P. Novelli (8) A. Rockman (9)
H. Scheel (9) M. Schneider (5) A. Strandberg
(6) R. Sussman (9) H. Tanimoto (10) V.
Velazco (7) J. Gille (4)
(1) Frontier Research Center for Global Change,
JAMSTEC, Yokohama, Japan (2) Institute of
Astrophysics and Geophysics, University of Liège,
, Liège, Belgium (3) Obukhov Institute of
Atmospheric Physics, , Moscow, Russia (4)
National Center for Atmospheric Research, ,
Boulder, United States (5) IMK-ISF,
Forschungszentrum Karlsruhe, , Karlsruhe,
Germany (6) Chalmers University of Technology, ,
Göteborg, Sweden (7) University of Bremen, ,
Bremen, Germany (8) NOAA, Climate Monitoring and
Diagnostic Laboratory, Boulder, United States (9)
IMK-IFU, Forschungszentrum Karlsruhe, ,
Garmisch-Partenkirchen, Germany (10) National
Institute for Environmental Studies, , Tsukuba,
Japan
BB emissions perturbed CO in High NH in periods
of strong fires (e.g., in 1998, 2002-03)
A B S T R A C T Carbon monoxide total column
amounts in the atmosphere were measured between
January 1996 and December 2003 in the High
Northern Hemisphere (30º-90º N, HNH) using
infrared spectrometers of high and moderate
resolution. They are compared to mixing ratios
measured in the surface layer and to total column
amounts measured from space by the Terra/MOPITT
instrument. All the data reveal increased CO
abundances in summer-autumn time in 2002 and 2003
in comparison to the preceding period. Maximum
anomalies of the HNH tropospheric burden compared
to the period 2000 - 2001 were observed in
September 2002 and August 2003. CO emission
anomalies between January 1996 and December 2003
were retrieved using a simple two-box model.
Annual emission anomalies in 2002 and 2003 were
98 and 142 Tg/year, respectively, and were close
to those in 1996 and 1998. It is most likely
that strong boreal forest fires in the HNH
induced the increased CO burdens. Available
ratios of CH4 and CO2 to CO were employed for
assessments of the BB impact on methane and
carbon dioxide.
M e a s u r e m e n t s
Monthly mean CO total column amounts in
molecules/cm2. Blue line is reference CO,
averaged over 2000 2001.
M E T H O D S CO total column amounts were
derived from infrared solar observations with
Fourier transform spectrometers (FTIR) operated
at seven stations located in the Arctic,
Scandinavia, Asia, the European Alps, and the
subtropical Atlantic. The high resolution spectra
(better than 0.005 cm-1) were fitted with
calculated spectra, and CO vertical profiles were
retrieved only total column amounts have been
used in this report. Near Moscow, Russia, total
column amounts of CO were derived from the
spectra of a grating spectrometer with a
resolution of 0.2 cm-1. The random and systematic
errors of a single total column measurement of CO
were estimated as 2-3 and 5, respectively.
The satellite-borne MOPITT (Measurements Of
Pollution In The Troposphere) instrument is a
thermal IR nadir-viewing gas correlation
radiometer. MOPITT uses a cross-track scan, which
allows for almost complete coverage of the
Earths surface in about 3 days, with individual
pixels of 22 km 22 km horizontal
resolution. The data were compared to local
CO concentrations in air samples collected in the
surface atmospheric layer by the NOAA/CMDL
Cooperative Air Sampling Network and by other
programs. Most of these measurements were made by
gas chromatography/HgO reduction detection using
instruments from Trace Analytical, Inc. At some
stations, CO mixing ratios were measured
continuously using non-dispersive gas correlation
IR instruments.
A case of peat fires.
The data for two ground sites and MOPITT averaged
within 200 km radius around. Normally CO columns
over Moscow exceed Zvenigorod values up to 50
due to the urban pollution. However, during
several days in summer-autumn CO columns over
Zvenigorod were triple as large comparing to
normal ones, and exceeded typical columns over
the Moscow center. MOPITT detected much lower
increase in CO column, because of its low
sensitivity to the boundary layer.
All the observation stations detected anomalously
high CO abundance, comparing to 2000-2001, in
1996, 1998, 2002 and 2003 (as well as MOPITT in
2002-2003). The anomaly of CO column over
Zvenigorod in some days of July and September,
2003 was considered as regional effect these
days were omitted.
C O e m i s s i o n
C O b u r d e n
M o d e l
BLFT refers to burdens calculated from
surface-based mixing ratios (for BL) merged with
in-situ and total column measurements at mountain
sites (for FT). TC, FTIR is based on
spectroscopic measurements at low-altitude sites.
Fire counts are from ATSR data.
Two-box model was used for calculation of CO
emission in HNH. MLNH was adopted from
surface-based CMDL measurements (Novelli et al.,
2003).
Note a different behavior of CO in the FT (blue)
and in the BL (red) in 1998 and in 2002. Also
note an influence of Indonesian fires (after
October, 1997) and Mexican fires (April, 1998) on
CO in mid latitudes of NH. All other spikes are
caused by the mid-latitude fires.
TOMS aerosol. Note red spots in NH multitudes
Seasonal patterns
Whether a repeatability of strong forest fires
increases? What may be their impact on CO2 and
CH4 burdens?
CO emission anomalies were multiplied by CH4/CO
and CO2/CO ratios Andreae Merlet, 2001
CH4/CO 1/3.8 (molar)
Box Model
Inter-annual variability
CH4/CO 1/40 (molar)
TAU(CH4) is for CH4OH reaction (OH by
Spivakovsky et al.) TAU(CO2) 190 years TAUTRANS
was the same as previously
If the boreal forest fires similar to those
observed in 2002-2003 would happen every year,
then carbon dioxide growth rate would increase by
30-50 and methane growth rate would be as high
as it has been in 1983 1988 (11 ppb/yr).