Surface Component Confusion

[whannah]

I'm confused as to what the surface component options meant when building the standalone CAM or SCAM.

The options in the CAM4 users guide are listed as
docn
socn
dom
none

But the options listed in the CCSM4 user guide are
pop
docn
xocn
socn

But the CAM user guide doesn't provide any description. So then if docn is the same in both lists, what is dom? is socn in the CAM documentation stand for "stub" or "slab"?

I've done a bunch of looking around but I must be looking in the wrong place, any help is appreciated.

 

[eaton]

When building standalone CAM4 the default data ocean component is "dom". This is a CAM specific data ocean model, meaning that it uses the same data structures as CAM and actually "use associates" some CAM modules, so it is not an independent component. It is the same data ocean code that was used in older CAM models (e.g., CAM3 and CAM2), but it has been refactored to have the component interfaces necessary to plug it into the CCSM coupler.

The "docn" data ocean model is completely independent of CAM and doesn't have to run on CAM's grid. Although "docn" is listed as a possible ocean component in the CAM4 user's guide, the option is not fully functional. It will be fully functional in the CAM version which will be part of the upcoming CESM-1.0 release. When running a "standalone CAM" configuration via a CCSM F compset, the data ocean model used is "docn".

socn is "stub ocean". This is used in standalone CAM for configurations where there are no surface interactions, such as when running with the adiabatic or ideal physics options.

A slab ocean is available, but only when running via the CCSM scripts using an E compset. This is implemented using docn as the data ocean component and cice in a fully active mode (rather than in a "thermodynamic only" mode which is how CAM standalone uses cice).

 

[whannah]

Thanks, that helps. But when I try to compile the CAM (in SCAM mode) the output of make command looks as if its expecting this directory:

.../ccsm4_working_copy/models/ocn/dom

but this directory doesnt seem to show up in the subversion repository, so what am I missing here?

 

[eaton]

CAM's Makefile gets the list of directories that it looks in for the source files from the file called Filepath which is generated when you run configure. If I run configure as follows (CAM_ROOT indicates the root directory of the source tree):

% $CAM_ROOT/models/atm/cam/bld/configure -dyn eul -hgrid 8x16 -scam -nospmd -nosmp

Then the Filepath file contains

$CAM_ROOT/models/atm/cam/src/utils/cam_dom

This is the current location of the CAM's dom code. The location you mentioned (../models/ocn/dom) was valid for many of the ccsm4 development versions, but is not correct for the release code. That directory will be found in the developer's repository, but not in the public release repository.

 

[whannah]

Sweet, I was able to get that code and modify the configure file to point to that directory.

Thanks for the help!