1 / 15

Design and Development of MAQM, an Air Quality Model Architecture with Process-Level Modularity

Design and Development of MAQM, an Air Quality Model Architecture with Process-Level Modularity. Weimin Jiang, Helmut Roth, Qiangliang Li, Steven C. Smyth, Fuquan Yang. Outline. Why is process-level (PL) modularity crucial for AQ models ?

trisha
Download Presentation

Design and Development of MAQM, an Air Quality Model Architecture with Process-Level Modularity

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Design and Development of MAQM, an Air Quality Model Architecturewith Process-Level Modularity Weimin Jiang, Helmut Roth, Qiangliang Li, Steven C. Smyth, Fuquan Yang

  2. Outline • Why is process-level (PL) modularity crucial for AQ models ? • What did we do in initiating a new generation of AQ model with PL modularity? • The conceptual MAQM architecture and its implementation in FORTRAN • The MAQM/CMAQ model • Possible future work • Acknowledgements CMAS Conference, Chapel Hill

  3. Why PL modularity ? Complicated atmos. processes & rapidly evolving AQ science Air quality model with process-level modularity Simple & transparent structure; Transferable code; Well structured model science & algorithms; Localised errors & bugs; Flexible process analysis capability. Broad community participation in model development and improvement Complete and robust model science CMAS Conference, Chapel Hill

  4. What did we do ? • MAQM: a new software architecture for air quality models • MAQM = Modular Air Quality Model; • Treats processes as individual blocks; • Blocks can be added, removed, replaced, modified, reorganized. • MAQM/CMAQ: a 3-D air quality model based on the MAQM architecture and mostly on the CMAQ science • Developed new pre-processors, MAQM data modules, the MAQM driver, and some MAQM process modules; • Extracted CMAQ algorithms/code and converted them into MAQM process modules; • Integrated all the pre-processors, MAQM data modules and MAQM process modules into a complete model. CMAS Conference, Chapel Hill

  5. The conceptual MAQM architecture

  6. MAQM components & design principles • 2 types of structural components: • Status; • Process. • 6 design principals: • Uniqueness of shared status information: global status data repository; • Self-contained process modules; • Structural separation of process modules; • Structural separation and linkages of status and processes; • Simple MAQM driver and its interface with process modules; • Minimized usage of hardcoding and repetitive code. CMAS Conference, Chapel Hill

  7. MAQM implementation in FORTRAN • MAQM global status data repository a set of FORTRAN data modules • MAQM process modules FORTRAN modules, sets of self-contained FORTRAN subroutines and/or functions • Process modules access data module components via the USE statements and the ONLY option at any levels • Simple MAQM driver calls to process modules: one way passing of time stamp and time step only • Example: software structure of MAQM/CMAQ  next slide CMAS Conference, Chapel Hill

  8. ... ... ...

  9. Emission Meteorology Gas_chem Advection ...... ... ... ... ...

  10. Emission Meteorology Gas_chem Advection ...... ... ... ... ...

  11. MAQM/CMAQ: details (1) • saprc99_ae4_aq_SVOC mechanism: • Modified from saprac99_ae4_aq; • Processed through PROCCHEM chemical mechanism processor. • Generalized CMAQ modal PM approach; • 5 global data modules: grid, gas, aero, met, const • 20 process modules: optional and replaceable • grid init_met int_gas init_aero • BConc_gas BConc_aero emission gas_chem • nucleation condensation inor_aero SOA • coagulation advection diffusion cloud • ddep_gas ddep_part meteorology output

  12. MAQM/CMAQ: details (2) • Inputs: optional depending on the process modules used. • IC and BC: ASCII files allowing different concentrations in different grid cells; • Meteorology, emissions, photolysis: same as CMAQ. • Outputs: • Three output files in I/O API format for each day: • GasConc_[yyyyddd]: gas concentrations; • Aero_Conc_[yyyyddd]: modal aero quantities (conc, Dg, sg) • PMx_[yyyyddd]: total and speciated PM0.01, PM0.1, PM1, PM2.5, PM5, PM10; • size cut-offs can be changed by users. • Conventional or SI units: user selected.

  13. Possible future work • Almost endless possibilities by the community, e.g. • New/restructured models using the MAQM architecture • Module-by-module science investigation and improvement • New and alternative process modules • Revised meteorology and emission modules to use input files from alternative sources • On-line meteorology and/or emission modules: • Possibilities: air quality meteorology • emission • Time- and location-varying boundary conditions • Process impact/sensitivity analysis

  14. Acknowledgements • US EPA: • The CMAQ model; • Early ideas of AQM modularity; • Community modelling concept. • All the organizations that contributed to the CMAQ code that we adapted/adopted. • CMAS: • Distributing and supporting CMAQ and other relevant modelling tools; • Organizing and facilitating community-wide discussions. • Dr. Jack Chen of our group: comments and suggestions. CMAS Conference, Chapel Hill

  15. CMAS Conference, Chapel Hill

More Related