Articles | Volume 13, issue 15
Atmos. Chem. Phys., 13, 7405–7413, 2013
Atmos. Chem. Phys., 13, 7405–7413, 2013

Research article 02 Aug 2013

Research article | 02 Aug 2013

ACE-FTS observations of acetonitrile in the lower stratosphere

J. J. Harrison1 and P. F. Bernath1,2 J. J. Harrison and P. F. Bernath
  • 1Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
  • 2Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia 23529, USA

Abstract. This work reports the first infrared satellite remote-sensing measurements of acetonitrile (CH3CN) in the Earth's atmosphere using solar occultation measurements made by the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) between 2004 and 2011. The retrieval scheme uses new quantitative laboratory spectroscopic measurements of acetonitrile (Harrison and Bernath, 2012). Although individual ACE-FTS profile measurements are dominated by measurement noise, median profiles in 10° latitude bins show a steady decline in volume mixing ratio from ~150 ppt (parts per trillion) at 11.5 km to < 40 ppt at 25.5–29.5 km. These new measurements agree well with the scant available air- and balloon-borne data in the lower stratosphere. An acetonitrile stratospheric lifetime of 73 ± 20 yr has been determined.

Final-revised paper