Evidence for short sulfur di oxide lifetimes in the atmosphere an in situ measurement of atmospheric sulfur di oxide lifetime using cosmic ray produced sulfur 38
Junkermann, W.; Roedel, W.
Atmospheric Environment 17(12): 2549-2554
ISSN/ISBN: 0004-6981 Accession: 005409567
A method for the determination of the in-situ lifetime of atmospheric SO2 was developed, using cosmic ray produced radioactive 38S. The 38S production rate by cosmic rays and the 38SO2 radioactivity of atmospheric samples were measured. The lifetimes of SO2 were obtained by comparison of the 38SO2 concentrations actually measured and modelled concentrations; the modelling took into account vertical mixing, dry deposition and radioactive decay, but not in-situ conversion into particulate S (horizontal mixing was neglected in the model). The apparent lifetimes determined by the 38S-method, ranging between 1/2 h and a few h in most cases, were shorter than lifetimes previously reported. Lifetimes seemed to be strongly influenced by solar radiation. Simple S balance considerations gave further evidence for short SO2 lifetimes in the atmosphere.