Robinson, N. H. and Hamilton, J. F. and Allan, J. D. and Langford, Ben and Oram, D. E. and Chen, Q. and Docherty, K. and Farmer, D. K. and Jimenez, J. L. and Ward, M. W. and Hewitt, C. N. and Barley, M. H. and Jenkin, M. E. and Rickard, A. R. and Martin, S. T. and McFiggans, G. and Coe, H. (2011) Evidence for a significant proportion of Secondary Organic Aerosol from isoprene above a maritime tropical forest. Atmospheric Chemistry and Physics, 11 (3). pp. 1039-1050. ISSN 1680-7316
Full text not available from this repository.Abstract
Isoprene is the most abundant non-methane biogenic volatile organic compound (BVOC), but the processes governing secondary organic aerosol (SOA) formation from isoprene oxidation are only beginning to become understood and selective quantification of the atmospheric particulate burden remains difficult. Organic aerosol above a tropical rainforest located in Danum Valley, Borneo, Malaysia, a high isoprene emission region, was studied during Summer 2008 using Aerosol Mass Spectrometry and offline detailed characterisation using comprehensive two dimensional gas chromatography. Observations indicate that a substantial fraction (up to 15% by mass) of atmospheric sub-micron organic aerosol was observed as rnethylfuran (MF) after thermal desorption. This observation was associated with the simultaneous measurements of established gas-phase isoprene oxidation products methylvinylketone (MVK) and methacrolein (MACR). Observations of MF were also made during experimental chamber oxidation of isoprene. Positive matrix factorisation of the AMS organic mass spectral time series produced a robust factor which accounts for an average of 23% (0.18 mu g m(-3)), reaching as much as 53% (0.50 mu g m(-3)) of the total oraganic loading, identified by (and highly correlated with) a strong MF signal. Assuming that this factor is generally representative of isoprene SOA, isoprene derived aerosol plays a significant role in the region. Comparisons with measurements from other studies suggest this type of isoprene SOA plays a role in other isoprene dominated environments, albeit with varying significance.