1Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
2Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia 23529, USA
Received: 05 Dec 2012 – Discussion started: 04 Feb 2013
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.
Revised: 21 Jun 2013 – Accepted: 24 Jun 2013 – Published: 02 Aug 2013
Harrison, J. J. and Bernath, P. F.: ACE-FTS observations of acetonitrile in the lower stratosphere, Atmos. Chem. Phys., 13, 7405-7413, doi:10.5194/acp-13-7405-2013, 2013.