Atmospheric Chemistry and Physics (May 2008)

CO measurements from the ACE-FTS satellite instrument: data analysis and validation using ground-based, airborne and spaceborne observations

  • C. Clerbaux,
  • M. George,
  • S. Turquety,
  • K. A. Walker,
  • B. Barret,
  • P. Bernath,
  • C. Boone,
  • T. Borsdorff,
  • J. P. Cammas,
  • V. Catoire,
  • M. Coffey,
  • P.-F. Coheur,
  • M. Deeter,
  • M. De Mazière,
  • J. Drummond,
  • P. Duchatelet,
  • E. Dupuy,
  • R. de Zafra,
  • F. Eddounia,
  • D. P. Edwards,
  • L. Emmons,
  • B. Funke,
  • J. Gille,
  • D. W. T. Griffith,
  • J. Hannigan,
  • F. Hase,
  • M. Höpfner,
  • N. Jones,
  • A. Kagawa,
  • Y. Kasai,
  • I. Kramer,
  • E. Le Flochmoën,
  • N. J. Livesey,
  • M. López-Puertas,
  • M. Luo,
  • E. Mahieu,
  • D. Murtagh,
  • P. Nédélec,
  • A. Pazmino,
  • H. Pumphrey,
  • P. Ricaud,
  • C. P. Rinsland,
  • C. Robert,
  • M. Schneider,
  • C. Senten,
  • G. Stiller,
  • A. Strandberg,
  • K. Strong,
  • R. Sussmann,
  • V. Thouret,
  • J. Urban,
  • A. Wiacek

Journal volume & issue
Vol. 8, no. 9
pp. 2569 – 2594

Abstract

Read online

The Atmospheric Chemistry Experiment (ACE) mission was launched in August 2003 to sound the atmosphere by solar occultation. Carbon monoxide (CO), a good tracer of pollution plumes and atmospheric dynamics, is one of the key species provided by the primary instrument, the ACE-Fourier Transform Spectrometer (ACE-FTS). This instrument performs measurements in both the CO 1-0 and 2-0 ro-vibrational bands, from which vertically resolved CO concentration profiles are retrieved, from the mid-troposphere to the thermosphere. This paper presents an updated description of the ACE-FTS version 2.2 CO data product, along with a comprehensive validation of these profiles using available observations (February 2004 to December 2006). We have compared the CO partial columns with ground-based measurements using Fourier transform infrared spectroscopy and millimeter wave radiometry, and the volume mixing ratio profiles with airborne (both high-altitude balloon flight and airplane) observations. CO satellite observations provided by nadir-looking instruments (MOPITT and TES) as well as limb-viewing remote sensors (MIPAS, SMR and MLS) were also compared with the ACE-FTS CO products. We show that the ACE-FTS measurements provide CO profiles with small retrieval errors (better than 5% from the upper troposphere to 40 km, and better than 10% above). These observations agree well with the correlative measurements, considering the rather loose coincidence criteria in some cases. Based on the validation exercise we assess the following uncertainties to the ACE-FTS measurement data: better than 15% in the upper troposphere (8–12 km), than 30% in the lower stratosphere (12–30 km), and than 25% from 30 to 100 km.