National Aeronautics and Space Administration

The accompanying animation shows the growth of the GEOS atmospheric model source code, compiled by accessing the time history of the model code using Gource. The striking aspects of the animation include the early configuration as a “traditional” atmospheric general circulation model (AGCM) with modules for “dynamics,” “atmospheric physics,” and “land surface” followed by the sporadic “explosive” expansions of the modeling capabilities, especially as the packages of aerosol and chemistry grid components are added. Read more. [PDF]