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List of Abstracts 163P-Observations 2.1 ID:4399 10:30The effect of tropical islands on the chemical mixing of biogenics from the surface layer to the lowerstratosphereKaren Hornsby 1 , Paul Monks 1 , Nicola Warwick 2 , Glenn Carver 21 University of Leicester2 University of CambridgeContact: keh25@le.ac.ukIn recent years much interest has been shown in the composition of the tropical atmosphere from the surfaceto the tropopause. During June 2008 an extensive measurement campaign (OP3) was conducted from theground level in the canopy of the tropical rainforest of Borneo concurrently with aircraft flights over coastalareas, a mixture of virgin rainforest and palm plantations on the island. The aim of this campaign was to gaina better understanding of the chemical processes governing the tropical boundary layer and emissions fromchanging vegetation types. Tropical islands present a set of meteorological conditions that have the potentialto loft surface emissions into the upper troposphere/lower stratosphere. Presented here is a discussion of theimpact of introducing surface emissions to this region of the atmosphere on the chemical processingthroughout the entire air column, with reference to high resolution model data and measurements from theOP3 campaign. The data show the lifting lifetimes and the effect these tropical chimneys have on thedistribution of a range of biogenics and NOx, which in light of changing land usage have implications for theoxidative impact of the tropical region on global oxidative capacity.P-Observations 2.2 ID:4579 10:30Observations of Stratosphere-Troposphere Exchange Using Radar Windprofilers and Balloon-BorneOzonesondesDavid Tarasick 1 , Trevor Carey-Smith 2 , Wayne Hocking 3 , Huixia He 3 , Mohammed Osman 3 , StephenArgall 31 Environment Canada2 National Institute of Water and Atmospheric Research, New Zealand3 University of Western OntarioContact: david.tarasick@ec.gc.caTwice-daily ozonesondes have been launched during a number of short campaigns, incorporating nearbyradar windprofiler measurements, in Ontario and Quebec between 2005 and 2009. This novel combination ofobservations has demonstrated the existence of a strong relationship between apparent rapid changes intropopause height and stratosphere-troposphere exchange (STE). In general, stratospheric intrusions appearto follow the passage of upper level cyclones which temporarily force the mid-latitude jet stream south of theobserving locations. Since total ozone variations at extratropical latitudes are well-correlated with synopticscale meteorological disturbances, particularly tropopause height, this suggests that it may be possible torelate rapid changes in total ozone to the occurrence of ozone intrusions. Further examination shows thatwhere the radar- determined tropopause differs from the WMO thermal tropopause, the radar is typicallyresponding to the sharp gradients of potential temperature and humidity at the lower edge of a stratosphericintrusion. Radar appears to be a particularly good intrusion detector. In addition to explaining the radar’ssuccess at finding STE events, this fact can potentially be used to study the descent of layers of stratosphericorigin in the troposphere.iCACGP-IGAC 2010 14 July, 2010