1. Institute for Chemical Process and Environmental Technology Weimin Jiang and Helmut Roth Development of a Modularised Aerosol Module in CMAQ National Research Council of Canada Ottawa, Canada

2. Institute for Chemical Process and Environmental Technology Introduction Structure of the new aerosol module Current status of the module Future work

3. Institute for Chemical Process and Environmental Technology Introduction Need for modularity at aerosol process level:Need for modularity at aerosol process level: add, modify, remove and/or replace science and code for individual aerosol processes Two phasesTwo phases Phase 1: - detailed review and analysis of science, algorithms, and code in AERO2 - restructure and recode to modularise AERO2 Phase 2: science improvement + new process submodules

4. Institute for Chemical Process and Environmental Technology Structure of the New Aerosol Module : modularity at aerosol process level

5. Institute for Chemical Process and Environmental Technology Structure of the New Aerosol Module : Separation of data and executable code

6. Institute for Chemical Process and Environmental Technology Structure of the New Aerosol Module : code flexibility and generality Flexibility to add and change data elements incl. species and size names as well as propertiesFlexibility to add and change data elements incl. species and size names as well as properties Applying same executable code to different data elements within same data objectsApplying same executable code to different data elements within same data objects Loop-based code operating on arrays instead of repetitive code blocks based on species and mode namesLoop-based code operating on arrays instead of repetitive code blocks based on species and mode names

7. Institute for Chemical Process and Environmental Technology Current Status of the Module

9. Institute for Chemical Process and Environmental Technology Future work Complete testing and debugging of the new CMAQ built with various combinations of submodules of the new aerosol moduleComplete testing and debugging of the new CMAQ built with various combinations of submodules of the new aerosol module Change and/or add new aerosol process submodules:Change and/or add new aerosol process submodules: - Use NRC Canada code - Analyse and use new science code in the CMAQ releases, e.g., AERO3 - Collaborate with the community to develop new aerosol process submodules Focus on SOA and primary PM in the near futureFocus on SOA and primary PM in the near future

10. Institute for Chemical Process and Environmental Technology Acknowledgements Models-3 team of U.S. EPA: AERO2 module Environment Canada: emissions and meteorological data used for model testing Program of Energy Research and Development (PERD) in Canada: funding support Mr. Éric Giroux of our group at NRC Canada: technical support

11. Institute for Chemical Process and Environmental Technology Thank you !