Tropospheric OH formation by ozonolysis of terpenes

The formation of hydroxyl radicals in the reaction of ozone with a number o f monoterpenes has been searched for under true atmospheric conditions. In all cases OH is produced showing efficiencies in some cases approaching uni ty, that is for each ozone molecule that reacts about one OH molecule is de tected. This observation makes the ozonolysis of the monoterpenes a signifi cant source of OH in the troposphere, which competes under favourable condi tions with the radiation-based production via ozone photolysis in the prese nce of water vapor. Another product formed in this reaction which has been observed simultaneously with OH is formaldehyde. (C) 1998 Elsevier Science B.V. All rights reserved.