1. AMMA-UK/EU Centre for Atmospheric Science University of Cambridge, UK Prof. John Pyle Glenn Carver Neil Harris James Levine Andrew Robinson Nicola Warwick Xin Yang Centre for Atmospheric Science University of Cambridge

2. Chemical Modelling Aims  Model studies in support of measurements. How best to do this?  Understanding the TTL and role in transporting chemical species between troposphere and stratosphere. Relative role of transport and chemistry in determining TTL composition.  Regional budget calculations. Global transport studies of local emissions and impact on tropospheric and lower stratospheric ozone.

3. Modelling tools  Trajectory studies of short lived species; simple box model calculations to study transport of SLS to UTLS region (collaboration with J. Methven)  Chemical transport model (e.g. p-TOMCAT); long range transport (possibly high resolution), budget studies  UM mesoscale model  Developments in chemistry schemes to suit measurements

4. Chemical modelling issues  Emission databases; AMMA-EU highlighted this as important.  Impact of convective systems on SLS; transport, scavenging.  Validation of NOx lightning emission in models.  Validation of new chemical schemes  Wide range of models covering various scales.

5. Modelling strategy  Links between dynamical and chemical modellers  Integration with AMMA-EU modelling activities; access to AMMA-EU model results; intercomparisons  Propose an AMMA-UK modelling subgroup meeting  Cover dynamical and chemical modelling issues related to AMMA  Discuss coordination of model integrations; dry run cases  Invite AMMA-EU model groups.