Gridded output files from version 5 of the Goddard Earth Observing System Data Assimilation System (GEOS-5 DAS), Version 5.1 (for 01/2004 - 08/2008) and Version 5.2 (for 09/2008- present day) on the CESM model grid: 0.5x0.6 degrees horizontal resolution. Variables are stored on a finite volume A-grid with a 0.5x0.6 degrees horizontal resolution and on a hybrid (pressure and sigma) vertical model grid. The data set is designed for the use of specified dynamics CESM or MOZART model runs.