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List of Abstracts 213addition to the homogeneous gas phase chemistry of SO 2 . Validation of our experimental data with a global3D chemical transport model, GEOS-Chem, is being investigated.Keywords: Gas-to-particle conversion, S-ratio, Sulphate, SO 2 , homogeneous and heterogeneous oxidation ofSO 2P-Observations 2.92 ID:4536 10:30Column measurements of atmospheric carbonyl sulfide at Wollongong, AustraliaNicholas Deutscher, Nicholas Jones, David Griffith, Clare Paton-Walsh, Christopher Chan-MillerUniversity of WollongongContact: ndeutsch@uow.edu.auCarbonyl sulfide is the most abundant atmospheric sulfur-containing species, and responsible for aconsiderable amount of the stratospheric aerosol layer during non-volcanic periods. COS has an oceanicsource and is taken up be soils and vegetation. Recently, considerable interest has centred on the possibilityof the vegetative uptake of COS provided a valuable constraint on the photosynthetic fraction of NPP.Here we present a 13 year time series of carbonyl sulfide column measurements obtained from solarabsorption Fourier transform infrared measurements at Wollongong, Australia. Wollongong is located on theeastern coast of Australia, ideally situated to observe the effects of both ocean and vegetation on atmosphericcarbonyl sulfide amounts.P-Observations 2.93 ID:4412 10:30High frequency continuous observations of Carbonyl SulfideRoisin Commane 1 , Greg Santoni 1 , David D. Nelson 2 , J. Barry McManus 2 , Mark S. Zahniser 2 , Steven C.Wofsy 11 Harvard University, Cambridge, MA, USA2 Aerodyne Research Inc., Billerica, MA, USAContact: rcommane@seas.harvard.eduCarbonyl sulfide (COS) is the most abundant sulfur containing gas in the atmosphere. COS is a surrogate forCO 2 uptake by plants during photosynthesis, but, unlike CO 2 , is not emitted by plants during respiration.Recent studies have suggested that COS may provide unique constraints on carbon assimilation by thebiosphere that are independent of the influence of respiration. While the loss of COS is dominated byvegetative uptake, COS is also subject to loss through uptake by oceans and soils, the magnitudes of whichare not known. Globally, COS mixing ratios have been found to vary from 350 to 550 pptv (parts pertrillion).Present measurement methods for measuring COS rely on canister sampling followed by laboratory analysisusing gas chromotography. While accurate and precise, this method is highly labour intensive, with limitedsampling sites and global coverage. We have developed a method for the direct, continuous, measurement ofCOS using an infrared laser absorption technique with a measurement precision (3 std deviation) of less than10 ppt in 30 s. The instrument uses a continuous wave quantum cascade laser operated at near roomtemperature, allowing for long term unattended operation. We present continuous data observed at a 1second sampling rate obtained from a suburban Boston sampling site during spring 2010.iCACGP-IGAC 2010 14 July, 2010