Articles | Volume 8, issue 13
Atmos. Chem. Phys., 8, 3529–3562, 2008

Special issue: Validation results for the Atmospheric Chemistry Experiment...

Atmos. Chem. Phys., 8, 3529–3562, 2008

  07 Jul 2008

07 Jul 2008

Validation of HNO3, ClONO2, and N2O5 from the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS)

M. A. Wolff1, T. Kerzenmacher1, K. Strong1, K. A. Walker1,2, M. Toohey1, E. Dupuy2, P. F. Bernath2,3, C. D. Boone2, S. Brohede4, V. Catoire5, T. von Clarmann6, M. Coffey7, W. H. Daffer8, M. De Mazière9, P. Duchatelet10, N. Glatthor6, D. W. T. Griffith11, J. Hannigan7, F. Hase6, M. Höpfner6, N. Huret5, N. Jones11, K. Jucks12, A. Kagawa13,14, Y. Kasai14, I. Kramer6, H. Küllmann15, J. Kuttippurath15,*, E. Mahieu10, G. Manney16,17, C. T. McElroy18, C. McLinden18, Y. Mébarki5, S. Mikuteit6, D. Murtagh4, C. Piccolo19, P. Raspollini20, M. Ridolfi21, R. Ruhnke6, M. Santee16, C. Senten9, D. Smale22, C. Tétard23, J. Urban4, and S. Wood22 M. A. Wolff et al.
  • 1Department of Physics, University of Toronto, Toronto, Ontario, Canada
  • 2Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada
  • 3Department of Chemistry, University of York, York, UK
  • 4Department of Radio and Space Science, Chalmers University of Technology, Gothenburg, Sweden
  • 5Laboratoire de Physique et Chimie de L'Environment CNRS – Université d'Orléans, Orléans, France
  • 6Forschungzentrum Karlsruhe and Univ. of Karlsruhe, Institute for Meteorology and Climate Research, Karlsruhe, Germany
  • 7National Center for Atmospheric Research (NCAR), Boulder, CO, USA
  • 8Columbus Technologies Inc., Pasadena, CA, USA
  • 9Belgian Institute for Space Aeronomy, Brussels, Belgium
  • 10Institute of Astrophysics and Geophysics, University of Liège, Liège, Belgium
  • 11School of Chemistry, University of Wollongong, Wollongong, Australia
  • 12Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA
  • 13Fujitsu FIP Corporation, Tokyo, Japan
  • 14Environmental Sensing and Network Group, National Institute of Information and Communications Technology (NICT), Tokyo, Japan
  • 15Institute of Environmental Physics, University of Bremen, Bremen, Germany
  • 16Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
  • 17New Mexico Institute of Mining and Technology, Socorro, NM, USA
  • 18Environment Canada, Toronto, Ontario, Canada
  • 19Atmospheric, Oceanic and Planetary Physics, University of Oxford, Oxford, UK
  • 20Institute of Applied Physics "Nello Carrara", National Research Center (CNR), Firenze, Italy
  • 21Dipartimento di Chimica Fisica e Inorganica, Università di Bologna, Bologna, Italy
  • 22National Institute of Water and Atmospheric Research Ltd., Central Otago, New Zealand
  • 23Laboratoire d'Optique Atmosphérique, Université des Sciences et Technologies de Lille, Villeneuve d'Ascq, France
  • *now at: LMD/CNRS Ecole polytechnique, Palaiseau Cedex, France

Abstract. The Atmospheric Chemistry Experiment (ACE) satellite was launched on 12 August 2003. Its two instruments measure vertical profiles of over 30 atmospheric trace gases by analyzing solar occultation spectra in the ultraviolet/visible and infrared wavelength regions. The reservoir gases HNO3, ClONO2, and N2O5 are three of the key species provided by the primary instrument, the ACE Fourier Transform Spectrometer (ACE-FTS). This paper describes the ACE-FTS version 2.2 data products, including the N2O5 update, for the three species and presents validation comparisons with available observations. We have compared volume mixing ratio (VMR) profiles of HNO3, ClONO2, and N2O5 with measurements by other satellite instruments (SMR, MLS, MIPAS), aircraft measurements (ASUR), and single balloon-flights (SPIRALE, FIRS-2). Partial columns of HNO3 and ClONO2 were also compared with measurements by ground-based Fourier Transform Infrared (FTIR) spectrometers. Overall the quality of the ACE-FTS v2.2 HNO3 VMR profiles is good from 18 to 35 km. For the statistical satellite comparisons, the mean absolute differences are generally within ±1 ppbv ±20%) from 18 to 35 km. For MIPAS and MLS comparisons only, mean relative differences lie within±10% between 10 and 36 km. ACE-FTS HNO3 partial columns (~15–30 km) show a slight negative bias of −1.3% relative to the ground-based FTIRs at latitudes ranging from 77.8° S–76.5° N. Good agreement between ACE-FTS ClONO2 and MIPAS, using the Institut für Meteorologie und Klimaforschung and Instituto de Astrofísica de Andalucía (IMK-IAA) data processor is seen. Mean absolute differences are typically within ±0.01 ppbv between 16 and 27 km and less than +0.09 ppbv between 27 and 34 km. The ClONO2 partial column comparisons show varying degrees of agreement, depending on the location and the quality of the FTIR measurements. Good agreement was found for the comparisons with the midlatitude Jungfraujoch partial columns for which the mean relative difference is 4.7%. ACE-FTS N2O5 has a low bias relative to MIPAS IMK-IAA, reaching −0.25 ppbv at the altitude of the N2O5 maximum (around 30 km). Mean absolute differences at lower altitudes (16–27 km) are typically −0.05 ppbv for MIPAS nighttime and ±0.02 ppbv for MIPAS daytime measurements.

Final-revised paper