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This repository contains the GEOS-Chem science codebase. Included in this repository are:

  • The source code for GEOS-Chem science routines;
  • Scripts to create GEOS-Chem run directories;
  • Template configuration files that specify run-time options;
  • Scripts to run GEOS-Chem tests;
  • Driver routines (e.g. main.F90) that enable GEOS-Chem to be run in several different implementations (as GEOS-Chem "Classic", as GCHP, etc.)

Version 12.9.3 and prior

GEOS-Chem 12.9.3 was the last version in which this "Science Codebase" repository was used in a standalone manner. For this reason, the latest release is frozen at 12.9.3.

Version 13.0.0 and later

GEOS-Chem 13.0.0 and later versions use this "Science Codebase" repository as a submodule within the GCClassic and GCHP repositories.

Releases for GEOS-Chem 13.0.0 and later versions will be issued at the GCClassic and GCHP Github repositories.

User Manuals

Each implementation of GEOS-Chem has its own manual page. For more information, please see:

About GEOS-Chem

GEOS-Chem is a global 3-D model of atmospheric chemistry driven by meteorological input from the Goddard Earth Observing System (GEOS) of the NASA Global Modeling and Assimilation Office. It is applied by research groups around the world to a wide range of atmospheric composition problems. Scientific direction of the model is provided by the international GEOS-Chem Steering Committee and by User Working Groups. The model is managed by the GEOS-Chem Support Team, based at Harvard University and Washington University with support from the US NASA Earth Science Division, the Canadian National and Engineering Research Council, and the Nanjing University of Information Sciences and Technology.

GEOS-Chem is a grass-roots open-access model owned by its users, and ownership implies some responsibilities as listed in our welcome page for new users. If you are interested in using GEOS-Chem, please contact the GEOS-Chem Support Team who will send you instructions for joining the user community and accessing the code.


Source code repository for the GEOS-Chem model of atmospheric chemistry and composition.







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