Complete this pre-run checklist

Now that you have created a run script for GEOS-Chem Classic, take a moment to make sure that you have completed all required setup steps before running your simulation.

First-time setup

  1. Make sure that your computational environment meets all of the hardware and software requirements for GEOS-Chem Classic.

Each-time setup

  1. Make sure that you have properly configured your login environment (i.e. load necessary software modules after login, etc.)

  2. Create a GEOS-Chem Classic run directory, and make sure that it is correct for the simulation you wish to perform.


    The initial restart file that is included with your run directory does not reflect the actual atmospheric state and should only be used to “spin-up” the model. We recommend a spin-up period of 6 months to 1 year (depending on the type of simulation you are using).

  3. Edit configuration files to specify the runtime behavior of GEOS-Chem Classic..


    Prior to running with GEOS-FP met fields, please be aware of several caveats regarding that data stream. (cf. The GEOS-FP wiki page).

  4. Configure and build the source code into an executable file.

  5. Copy a sample GEOS-Chem Classic run script to your run directory and edit it for the particulars of your simulation and computer system.

  6. Make sure that your run script contains the proper settings for OpenMP parallelization.

  7. Be aware of ways in which you can speed up your GEOS-Chem Classic simulations.