CMAQ 5.3.2 Release (October 2020)

Announcing the release of CMAQ version 5.3.2 (October 2020)

The U.S. EPA Office of Research and Development and the Community Modeling and Analysis System Center are pleased to announce the release of CMAQ version 5.3.2.

CMAQv5.3.2 includes significant updates to the CMAQ Integrated Source Apportionment Method (ISAM) and multiple minor fixes to address issues identified in CMAQv5.3.1. The new CMAQ-ISAM version includes substantial updates to the gas-phase chemistry apportionment algorithms that improves both physical and numerical aspects of the method. Users of ISAM are strongly encouraged to update to CMAQv5.3.2.

Download the source code and scripts, and access all documentation for this release from the USEPA GitHub repository,

Two-day test data for CMAQ version 5.3.2 are available from the CMAS Data Warehouse.

Please report any bugs or problems with this release to the CMAS User Forum,

Additional user support, including training courses and other CMAS-supported products is available through the CMAS Center website: