NORMAL-ALKANE STUDIES IN THE TROPOSPHERE .1. GAS AND PARTICULATE CONCENTRATIONS IN NORTH-ATLANTIC AIR

Simultaneous measurements of gas phase and paniculate concentrations of C9-C28 n-alkanes in clean air at the west coast of Ireland are reported. All n-alkanes were regularly present with gas phase concentrations between about 10 and 20 × 10-9 g m-3 STP, showing no systematic decrease above C13. Continental air showed higher concentrations. The fraction of alkanes attached to aerosol particles increases from less than 1% at low C-numbers to several per cent at high C-numbers. The carbon preference index is generally close to 1.0; seawater samples from that area exhibit similar distributions of n-alkanes as the gas phase. © 1979.