The chemistry of atmospheric bromine

Abstract

Bromine may act as a catalyst for recombination of ozone and could be more efficient than either nitric oxide or chlorine. The lower atmosphere contains small concentrations of gaseous bromine produced in part by marine activity, in part by volatilization of particulate material released during the combustion of leaded gasoline, with an additional contribution due to the use of methyl bromide as an agricultural fumigant. Observations by Lazrus et. al. (1975) indicate small concentrations of bromine, ∼ 10 −11 (v/v) in the contemporary stratosphere and appear to imply a reduction of approximately 0.3% in the global budget of O 3 . Estimates are given for future reductions in O 3 which might occur if the use of CH 3 Br as an agricultural fumigant were to continue to grow at present rates.