Advanced configuration of NorESM2

Creating a compset

The essential file to edit is

~/noresm/scripts/ccsm_utils/Case.template/config_compsets.xml ==

This examples shows how to simply add a to the “F_AMIP_CAM5” compset:

Under “”, add

<COMPSET sname="F_AMIP_CAM5-OSLO" alias="FAMIPOSLO" >AMIP_CAM5%OSLO_CLM40%SP_CICE%PRES_DOCN%DOM_RTM_SGLC_SWAV</COMPSET>

The “CAM5%OSLO” options have to be defined, so a line like this is needed:

<CAM_CONFIG_OPTS compset="_CAM5%OSLO" >-phys cam5 -cam_oslo aerlife</CAM_CONFIG_OPTS>

The compset needs a description, we also need the line

<desc compset="_CAM5%OSLO">cam 5 physcs and oslo aerosols</desc>

We could also define a specific use-case (namelist) for our compset. This would need a line like:

<CAM_NML_USE_CASE compset="_CAM5%OSLO" >my_namelist</CAM_NML_USE_CASE>

This would only work if the file my_namelist.xml exists as

noresm/models/atm/cam/bld/namelist_files/use_cases/my_namelist.xml

Setting up a case with the new compset and building the model

It should now be possible to create a new case directory, which we here name FAMIPOSLOtst and configure with 1 degree horizontal atmospheric resolution;

./create_newcase -case ../cases/FAMIPOSLOtst -compset FAMIPOSLO -mach hexagon -res f09_f09

and finally set up and compile the model:

cd ../cases/FAMIPOSLOtst ./cesm_setup ./FAMIPOSLOtst.build

Why does it work to change config_compsets.xml ?

In NorESM there are 3 new config-options for CAM:

-cam-oslo aerlife (turns on transport of oslo tracers)

-cam-oslo dirind (turns on interaction with radiation)

-cam-oslo warmclouds (turns on interaction with warm clouds)

They change number of tracers and turn on different preprocessor flags in in a script

models/atm/cam/bld/configure

To understand the implementation do:

svn diff -r 202 models/atm/cam/bld/configure

The options also need to be defined, see

models/atm/cam/bld/config_files/definition.xml

To see how the options were added, do:

svn diff -r 202 models/atm/cam/bld/config_files/definition.xml