Atmospheric Chemistry and Physics OH and HO2 chemistry in clean marine air during SOAPEX-2

• Main Authors: R. Sommariva, A. -l. Haggerstone, L. J. Carpenter, N. Carslaw, D. J. Creasey, D. E. Heard, J. D. Lee, A. C. Lewis, M. J. Pilling, J. Zádor
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2004
• Subjects: Austral; Grim; Southern Ocean
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.405.2071; http://hal.archives-ouvertes.fr/docs/00/29/54/46/PDF/acp-4-839-2004.pdf

Abstract. Model-measurement comparisons of HOx in extremely clean air ([NO]<3 ppt) are reported. Measurements were made during the second Southern Ocean Photochemistry Experiment (SOAPEX-2), held in austral summer 1999 at the Cape Grim Baseline Air Pollution Station in northwestern Tasmania, Australia. The free-radical chemistry was studied using a zerodimensional box-model based upon the Master Chemical Mechanism (MCM). Two versions of the model were used, with different levels of chemical complexity, to explore the role of hydrocarbons upon free-radical budgets under very clean conditions. The “detailed ” model was constrained to measurements of CO, CH4 and 17 NMHCs, while the “simple” model contained only the CO and CH4 oxidation mechanisms, together with inorganic chemistry. The OH and HO2