Intercomparaison du CO mesur

1
Intercomparaison du CO mesuré par MOPITT en visée
au nadir et par ACE en occultation solaire
complémentarités pour létude du transport de la
pollution Solène Turquety, Cathy Clerbaux, Kathy
Law, Juliette Hadji-Lazaro Service d'Aéronomie,
IPSL, Paris, France. Pierre-François Coheur,
Daniel Hurtmans, Catherine Wespes, Ariane Razavi,
Service de Chimie Quantique et Photophysique,
Université Libre de Bruxelles. Didier
Hauglustaine, Anne Cozic, Laboratoire des
Sciences du Climat et de lEnvironnement, IPSL,
Gif-sur-Yvette, France Christopher D. Boone,
Peter F. Bernath Department of Chemistry,
University of Waterloo, Waterloo, Canada
2
Importance of the long-range transport of
pollution from Asia
East central China Hong Kong
Heald et al., JGR, 2006
Clerbaux et al., 2006
Richter et al., Nature, 2005

• IPCC CO emissions 3 for East Asia and India
  between 2000 and 2100 (scenario A2p)
• NOx emissions 4
• Long-range transport has important implication
  for air quality in downwind regions
• Reaches a maximum in spring due to active
  anticyclone and strong westerly winds
• Transport mainly in the middle troposphere
• Trans-Pacific transport of pollution in 5-10 days

Is there information on Asian pollution in the
ACE solar occultation measurements in the middle
and upper troposphere?
3
ACE Atmospheric Chemistry Experiment

• ACE-SCISAT-1 is a Canadian mission launched on
  August 13th, 2003
• Primary instrument ACE-FTS, high resolution IR
  spectrometer
• Solar occultation measurement of atmospheric
  profiles of temperature, pressure and a series of
  trace gases during sunrise and sunset
• Modified global fit (Levenberg-Marquardt) Boone
  et al., 2005
• Retrieval of key species for tropospheric
  studies
• O3, H2O, H2O2, CO, CH4, C2H6, C2H2, HCN, CH3Cl,
  SF6, OCS, HNO3, PAN,
• Vertical resolution 4km in the middle and upper
  troposphere

http//www.ace.uwaterloo.ca/mission.htm
4
Exploiting the complementarities for the study of
long range transport

• Focus on March-April 2005, a time period with ACE
  observations at mid-latitudes
• Intercomparison of CO observations
• MOZAIC (in situ), MOPITT (nadir), ACE (solar
  occultation)
• Study transport event in March-April 2005 with
  the global model LMDz-INCA

5
ACE solar occultation measurements vs. MOZAIC in
situ data
Comparisons for March-April-May 2004 /- 2.5 ,
/- 1 day
20050506 (48N, 15E)
20050504 (46N, 72W)
ACE
ACE
MOZAIC
MOZAIC
250
200
6
Intercomparison of remote sensing CO measurements
Intercomparison of Level 2 retrievals from
different instruments Need to account for
characteristics of the retrievals.
Rodgers and Connor, 2003 Apply retrieval
characteristics of lower resolution measurement
(e.g. MOPITT) to higher resolution measurement
(e.g. in situ data, model simulations)
7
MOPITT nadir vs. ACE occultation measurements
ACE occultations - - ss8848.asc
Intercomparison /- 1 , same day MOPITT MOPITT
a priori profile ACE high resolution ACE/MOPITT
(smoothed)

• Good agreement ? 18
• MOPITT tends to give larger mixing ratios in the
  upper troposphere
• ACE observations allows complementary
  measurement of plume vertical structure

8
DOFs0.7
DOFs 2 information haute troposphère dans
MOPITT DOFs 1 biais ACE / MOPITT dans la
haute troposphère, liée à la contribution de la
basse troposphère dans MOPITT
9
LMDz-INCA global model simulation

• Global GCM LMDz (Laboratoire de meteorologie
  Dynamique, zoom), version 4 (http//www.lmd.jussie
  u.fr/lmdz)
• Chemistry module INCA (Interaction of Chemistry
  and Aerosols) NMHC version 2
• 85 chemical species over 300 reactions
  (Hauglustaine et al., 2005, http//www-lsceinca.ce
  a.fr/)
• Simulation using the nudged version, driven by
  ECMWF meteorological fields
• Resolution 3.75 longitude x 2.5 latitude, 19
  vertical levels (surface 3hPa)
• Anthropogenic emissions from EDGAR v.2 biogenic
  emissions from GEIA
• Biomass burning emissions (1st approximation)
  Climatology (average 1995-2003 from Van der Werf
  et al.) redistributed according to MODIS fire
  detection for 2005 (monthly emissions)

MOPITT CO _at_ 700hPa April 2005
SCIAMACHY tropospheric NO2 (KNMI) April 2005
INCA tropospheric NO2
INCA x MOPITT AK
Underestimate anthropogenic emissions (Asia)
Need more accurate biomass burning
10
Long-range transport from Asia in March-April 2005
11
Comparison of CO from ACE and the LMDz-INCA model
INCA _at_ 400 hPa 20050327-20050404
Average INCA distribution for the days of ACE
comparisons
12
Comparison of CO from ACE and the LMDz-INCA model
13
Comparison of CO from ACE and the LMDz-INCA model
14
Comparison of O3 from ACE and the LMDz-INCA model
INCA _at_ 400 hPa 20050327-20050404
Average INCA distribution for the days of ACE
comparisons
15
Comparison of O3 from ACE and the LMDz-INCA model
ACE occultation
16
CO
NOx
ACE occultation
O3 net production
Stratospheric intrusion?
Fraction of stratospheric O3
17
CO
NOx
O3 net production
Stratospheric intrusion?
Fraction of stratospheric O3
18
Conclusions

• ACE occultation measurements provide information
  on a series of trace gases with good vertical
  resolution in the upper troposphere
• CO measurements consistent with MOZAIC in situ
  and MOPITT satellite measurements
• Combined analysis with nadir measurements
  (better spatio-temporal resolution, lower
  vertical resolution) and global model provides
  information on the global context and transport
  pathways
• ACE gives detailed information on the chemical
  composition of air masses in the upper
  troposphere
• Interesting tool for the study of the long range
  transport

• Future work
• Comparisons to TES/Aura observations
• Improve emissions in the LMDz-INCA simulation
• using results from inverse modeling analyses
• Analysis of ozone production during the long
• range transport
• Assimilation complementary constraint from
• different observation geometry?
• Vertical resolution vs. number of observations
  intergrated?