The scripts for running CSIM coupled are documented in the CCSM3 User's Guide:
There are several configurations that may be of interest to ice modelers. The B configuration is the fully coupled model with active atmosphere, ice, land and ocean components communicating through the flux coupler. This configuration will result in the most realistic ice simulations.
The D configuration consists of CSIM, coupled to the
data atmosphere (datm6),
data ocean (docn6),
and data land (dlnd6),
components. This configuration runs quickly and is used for testing the software engineering aspects of the model. This configuration will not result in the best sea ice simulation, since docn6 does not allow ice growth in open ocean regions or leads, and the data read in by datm6 is from previous atmospheric model simulations.
The M configuration will result more realistic sea ice simulations than the D configuration. This setup replaces datm6 in the D congifuration with the latm6, data atmosphere model and the ocean mixed layer model within the ice model. The ocean mixed layer is a simple slab model which computes an ocean surface temperature and allows for ice formation due to ocean supercooling. More information on the formulation of this model can be found in the Scientific Document. latm6 runs on the T62 grid, and one year of NCEP forcing is included with this release.