HR: 0800h
AN: A21C-0888    [Abstracts]
TI: Production Rate of Hydroxyl Radicals in First-Year sea ice: A Modelling and Measurement Study.
AU: * France, J L
EM: j.france@gl.rhul.ac.uk
AF: Department of Geology, Royal Holloway University of London, Egham Hill TW20 0EX UK, Egham, TW20 0EX United Kingdom
AU: King, M D
EM: m.king@gl.rhul.ac.uk
AF: Department of Geology, Royal Holloway University of London, Egham Hill TW20 0EX UK, Egham, TW20 0EX United Kingdom
AU: Fisher, F N
EM: f.fisher@gl.rhul.ac.uk
AF: Department of Chemistry, Kings College, University of London, The Strand, London, WC2R 2LS United Kingdom
AU: Beine, H J
EM: harry@iia.cnr.it
AF: C.N.R. - IIA, Via Salaria, Km 29,3, 00016 Monterotondo Scalo, Rome, Italy
AB: Sea ice may be an oxidising medium, initiated by the production of hydroxyl radicals from the photolysis of nitrate and hydrogen peroxide. The depth integrated photolysis rate for hydroxyl radical production from both nitrate anions and hydrogen peroxide was calculated using derived scattering and absorption co-efficients for first-year sea ice at Terra Nova Bay, Antarctica as part of the CESIP campaign. The scattering and absorption cross-sections were derived with the radiation transfer model TUV-snow, using measured albedo and light penetration of the sea ice. The depth integrated photolysis rates illustrate that the photoproduction of hydroxyl radicals is an order of magnitude more efficient from hydrogen peroxide photolysis compared with nitrate photolysis. However, the rate of production of hydroxyl radicals is greater from the photolysis of nitrate due to the higher relative concentration of nitrate anions compared with hydrogen peroxide.
DE: 0750 Sea ice (4540)
DE: 0798 Modeling
DE: 4540 Ice mechanics and air/sea/ice exchange processes (0700, 0750, 0752, 0754)
DE: 4852 Photochemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005