CMAQ is distributed with a dataset that can be used to benchmark the CMAQ installation. In the CMAQ distribution, output data from CMAQ is bundled with the input data (including emissions and meteorology) that can be used to reproduce the reference results.

After completing the CMAQ benchmark case, the CCTM output files can be compared with the reference datasets provided in the distribution. If the benchmark case is run on a system similar to that used to create the reference data (Red Hat Linux with the Portland Group FORTRAN compiler), the results should differ by no more than 0.01% for every model species. Changing the optimization of the compiler or compiling on other operating systems with different compilers can lead to larger differences between the benchmark results and the reference datasets. The CCTM benchmark targets for operating systems/compilers other than the Red Hat Linux/Portland Group combination are differences less than 1% for every model species.