CPL Version 7.0
CCSM4
The CCSM4 Version of the Community Climate System Model has some significant changes compared to previous versions. In particular, CCSM4 is NOT run via multiple executables concurrently. There is now a top level driver and components are called via standard init, run, and finalize methods. Components can be run sequentially, concurrently, or in some mixed sequential/concurrent layout. A coupler component that runs on a subset of the total processors still exists in the system, and it carries out mapping (interpolation), merging, diagnostics, and other calculations. The name cpl7 refers to both the driver and coupler functionality in the CCSM4 system.
Documentation
CESM1.0
The version 7 coupler (cpl7) found in CESM1.0 is basically identical to the coupler in CCSM4. The cpl7 version does have some significant changes compared to CCSM3/cpl6 and previous versions. Component models are no longer implemented as multiple executables running concurrently, but rather as a single executable. The coupler's main program is now the main program for the entire coupled model. As before, the coupler main program coordinates the interaction and time evolution of the component models, but now component models appear as subroutines with standard init, run, and finalize methods. The coupler also has new functionality to arrange that component models run sequentially, concurrently, or in some mixed sequential/concurrent layout. Because it contains this type of control functionality, the main program is also called the driver. As before, the coupler also has functionality to carry out flux calculations, mapping (regridding), diagnostics, and other calculations -- this type of functionality can be run on a subset of the total processors. The name cpl7 refers to the driver functionality as well as this other type of functionality.
Documentation
CESM1.2
The CESM1.2 system (like the CESM1.0 system) is a single executable where the coupler main program coordinates the interaction and time evolution of the component models, and component models appear as subroutines with standard init, run, and finalize methods. The coupler also has new functionality to arrange that component models run sequentially, concurrently, or in some mixed sequential/concurrent layout. Because it contains this type of control functionality, the main program is also called the driver. The coupler also has functionality to carry out flux calculations, mapping (regridding), diagnostics, and other calculations -- this type of functionality can be run on a subset of the total processors. The name cpl7 refers to the driver functionality as well as this other type of functionality.