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Community Multiscale Air Quality Modeling System (CMAQ)

CMAQ Developers Guide

EPA welcomes submissions of new code to the CMAQ system from the user community. To facilitate the integration of new code into a future CMAQ public release, our team created the CMAQ Developers Guide. The Developers Guide describes general development practices within the CMAQ system and step-by-step instructions on how to contribute source code to the EPA CMAQ code repository hosted on GitHub. Prospective developers are asked to read the guide prior to starting a project within the CMAQ framework.

General guidelines for new code submissions include:

  • Check that the code is consistent with the current model version.
  • Use consistency in coding practices for any new code.
  • Document all code testing activities including results showing:
    • A benchmark case for the revised code (including documentation of input data, output data and runscripts).
    • Impacts on computational time performance.
    • Viability on different platform-compiler combinations (at least Intel, GNU and Portland Group Fortran).
  • Document or provide references to the peer-reviewed literature supporting new science algorithms.
  • Provide ongoing support and technical guidance for the use of the code updates.

The CMAQ Developers Guide is available through GitHub with the official release of CMAQv5.2.1 (March 19, 2018).