Jump to main content.

Contact Us

CMAQ 4.5.1 Release Notes

The Model Development Team is pleased to announce that CMAQ version 4.5.1 has been delivered to CMAS for public release. You can access the model from the CMAS. Exit EPA Disclaimer.

Below is a list of updates since the version 4.5 release:

  1. Mercury
    • Added mercury modeling capability (see MERCURY_NOTES)
  2. Chemistry
    • Beta-version of CB05 (see CB05_NOTES)
    • Updates to the SAPRC99/air toxics chemistry and associated EBI solver
  3. Aerosols
    • Recomputed tabulated binary activity coefficients in ISORROPIA
  4. PBL modeling
    • Eliminate surrogate JACOBF, since now in mcip output
    • Code change to accommodate more ways to specify mol/s for emissions units, assumes mass units no longer used
    • Cap the application of the kzmin algorithm at 500 m above surface
  5. Clouds
    • Floor-value set for Aitken-mode mass in getalpha.f to avoid possible NANs
    • Aqueous Chemistry:
    • Integration timestep calculation bug fix
    • Discontinued aerosol species lumping: separate elemental carbon from primary aerosol; split organic aerosols into primary, secondary biogenic, and secondary anthropogenic
    • The AE_A2AQ.EXT file for all chemical mechanisms was updated to reflect the new species treatment in the cloud model
    • Fixed 3rd moment calc to include EC and primary organics (not secondary)
    • Re-arranged logic for setting Cl & Na ending conc
    • Added pointers/indirect addressing for arrays WETDEP and LIQUID
  6. Advection
    • Bug fixes: Fortran 90 code interface for ASTEP and CFL number check
  7. Parallel I/O library
    • More robust allocation error checking and ensuring that I/O processor can't access non-existing memory
    • Add worker and I/O processors partition scheme
  8. Process Analysis
    • Add correct methods to access mass-conserving advection process
    • Changed the names of some of the operators to be 4 chars in length to help insure unique compound variable names
    • Change NPROCS in PA_CMN.EXT to NPRCS to avoid name conflict with CCTM multiprocessing variable
    • Bug fixes: gas species family flag array index, N_IPR_SPC value for no integrated process rates option, remove blank character in 'Air density' species name


    • Fix erroneous operation in parallel CCTM for Process Analysis subdomains that are windowed from model domain
    • Move code dealing with process analysis from Fortran 90 module HGRD_DEFN to module PAGRD_DEFN and modify PAGRD_DEFN to handle subdomains that are windowed from model domain


    • Move barrier in wr_aconc.F to avoid race condition (Michael Bane's suggestion)

Contact the Atmospheric Modeling and Analysis Web editor to ask a question, provide feedback, or report a problem

Jump to main content.