EMISSION OF METHYL-BROMIDE FROM BIOMASS BURNING

Bromine is, per atom, far more efficient than chlorine in destroying s tratospheric ozone, and methyl bromide is the single largest source of stratospheric bromine. The two main previously known sources of this compound are emissions from the ocean and from the compound's use as a n agricultural pesticide. Laboratory biomass combustion experiments sh owed that methyl bromide was emitted in the smoke from various fuels t ested. Methyl bromide was also found in smoke plumes from wildfires in savannas, chaparral, and boreal forest. Global emissions of methyl br omide from biomass burning are estimated to be in the range of 10 to 5 0 gigagrams per year, which is comparable to the amount produced by oc ean emission and pesticide use and represents a major contribution (ap proximate to 30 percent) to the stratospheric bromine budget.