On the capability of IASI measurements to inform about CO surface emissions A. Fortems-Cheiney1, F. Chevallier1, I. Pison1, P. Bousquet1, C. Carouge1,*, C. Clerbaux2, P.-F. Coheur3, M. George2, D. Hurtmans3, and S. Szopa1 1Laboratoire des Sciences du Climat et de l'Environnement, CEA-CNRS-UVSQ, Gif-sur-Yvette, France 2UPMC Univ Paris 06, CNRS UMR8190, LATMOS/IPSL, Paris, France 3Spectroscopie de l'atmosphère, Chimie Quantique et Photophysique, Université Libre de Bruxelles, Brussels, Belgium *now at: Division of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, USA
Abstract. Between July and November 2008, simultaneous observations were conducted by several
orbiting instruments that monitor carbon monoxide in the atmosphere, among them the
Infrared Atmospheric Sounding Instrument (IASI) and Measurements Of Pollution In
The Troposphere (MOPITT). In this paper, the concentration retrievals at about 700 hPa
from these two instruments are successively used in a variational Bayesian system
to infer the global distribution of CO emissions. Starting from a global emission
budget of 479 Tg for the considered period, the posterior estimate of CO emissions
using IASI retrievals gives a total of 643 Tg, which is in close agreement with
the budget calculated with version 3 of the MOPITT data (649 Tg). The regional
totals are also broadly consistent between the two inversions. Even though our
theoretical error budget indicates that IASI constrains the emissions slightly
less than MOPITT, because of lesser sensitivity in the lower troposphere,
these first results indicate that IASI may play a major role in the quantification of the emissions of CO.
Citation: Fortems-Cheiney, A., Chevallier, F., Pison, I., Bousquet, P., Carouge, C., Clerbaux, C., Coheur, P.-F., George, M., Hurtmans, D., and Szopa, S.: On the capability of IASI measurements to inform about CO surface emissions, Atmos. Chem. Phys., 9, 8735-8743, doi:10.5194/acp-9-8735-2009, 2009.