GEOS–Chem is a global 3-D chemical transport model (CTM) for atmospheric composition. It principally uses meteorological input from the Goddard Earth Observing System (GEOS) of the NASA Global Modeling and Assimilation Office, but can use other meteorological inputs as well. 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. Central management of the model is provided by the Atmospheric Chemistry Modeling Group at Harvard University.

The GEOS–Chem community welcomes new members interested in working with the model. GEOS–Chem is a grass-roots cooperative model owned by its user community, and ownership means some responsibilities as listed in our welcome page for new users. Please contact Model Scientist Daniel J. Jacob to join the user community and access the code.

Please proceed to Model Overview for further information and links.