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CAM4 single column mode - GABLS

I am running CAM4 as a standalone model, part of the CCSM4.0, in a single column mode.

I have adapted the available PBS script for a Cray machine, run-cray.csh, to the local CRAYXT4 machine (hexagon), and configured the CAM4 model into a single column mode. The model is running with the available forcing IOP file, arm0795v1.2.nc, and also with a home made IOP file based on SHEBA data.

Now I am trying to set up the theoretical GABLS test (www.gabls.org), where the model is forced with a constant geostrophic wind and a decreasing surface temperature. When I set all advection fields and the vertical velocities to zero in the IOP file (large scale forcing), and initialize with a constant 8 m/s wind at all vertical levels, no boundary layer is developing, i.e. all horizontal velocities are equal to the initialized velocities during a 9 h model time!

a) How do I force the model with a geostrophic wind in the SCM mode?
b) Why doesn't the physics in the model adjust the wind speed in the boundary layer?


Configuration:

/configure -dyn eul -hgrid 48x96 -nlev 30 -scam -nospmd -nosmp -v -test -cam_exe scam


Namelist (where runtype = startup, startymd = 19000101, starttod = 0, stop_n = 3240):

/build-namelist -v -case $case -runtype $runtype -test -ignore_ic_date
-namelist "&camexp start_ymd=$startymd start_tod=$starttod stop_option='nsteps' stop_n=$stop_n
/ &scam scmlat=76 scmlon=194 / &cam_inparm iopfile='/work/bergh/inputdata/gabls_iop_2.nc'
/ &cam_imparm ncdata='/work/bergh/inputdata/cami_0000-09-01_64x128_L30_c031210_gabls_new.nc'
/ &dom_inparm bndtvs='/work/bergh/inputdata/sst_HadOIBl_bc_48x96_clim_c050526.nc'
/ &dom_inparm focndomain='/work/bergh/inputdata/domain.camocn.48x96_gx3v7_100114.nc'
/ &cam_inparm avgflag_pertape = 'A' , 'I'
/ &cam_inparm nhtfrq = 0 , 1
/ &cam_inparm mfilt = 1 , 3240
/ &cam_inparm scm_iop_srf_prop = .true.
/ &cam_inparm dtime = 10
/ &cam_inparm fincl2 = 'PBLH','TAUX','TAUY','U','V','OMEGA','OMEGAT','T','Q','Z3','TKE','TS','PS','LHFLX','SHFLX','DIVU','DIVV','DIVT','DIVQ','USTAR' /"
-config $blddir/config_cache.xml


Please tell me if more information is needed!
Any help would be much appreciated!

Best regards,
Jon
 
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