Aerosol-Mediated Partitioning of Stratospheric Cly and NOy at Temperatures Above 200 K

• Published in: Geophysical research letters Vol. 26; no. 3; pp. 299 - 302
• Main Authors: Michelsen, H. A., Spivakovsky, C. M., Wofsy, S. C.
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 01-02-1999; American Geophysical Union
• Subjects: Atmospheric composition. Chemical and photochemical reactions; Earth, ocean, space; Exact sciences and technology; External geophysics; Physics of the high neutral atmosphere; Nitrogen oxide; Chlorine Nitrates; Temperature dependence; Hydrogen Chlorides; Production rate; Chemical reaction; Stratosphere; Models; Stratospheric aerosol; Photochemistry
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/1998GL900281

Rates of aerosol‐mediated reactions involving inorganic halogen species are small but non‐negligible for moderate aerosol abundances at temperatures of 200–210 K. We have used a photochemical model to demonstrate that at these temperatures such reactions provide a significant sink for HCl. Gas‐phase production rates are slower for HCl than for ClNO3. The net result is preferential partitioning of Cly into [ClNO3] to compensate for the accelerated loss of [HCl]. Under such conditions, [HNO3] decreases in response to enhanced partitioning of NOy into [ClNO3]. The results indicate a high sensitivity and synergistic response of HCl, ClNO3, and HNO3 distributions to aerosol content and temperature.