Perturbation Growth Test, cam3_1_9, FV, 1.9x2.5

Legend

perturbation: IBM(P4)          - growth of a perturbation on bluesky

difference: SGI(O3800)-IBM(P4) - growth of the difference between runs on
                                 tempest and bluesky

difference: IBM(AMD64)-IBM(P4) - growth of the difference between runs on
                                 lightning and bluesky

Results

This test validates that running cam3_1_9 on tempest (SGI Origin 3800) and lightning (IBM cluster of 2 processor Opteron nodes) introduces only roundoff level differences relative to a run on bluesky (IBM Power 4).

Test details

Source tag: cam3_1_9

Configuration:

On IBM and SGI
% configure -dyn fv -res 1.9x2.5 -pergro -spmd -smp

On AMD64 cluster
% configure -dyn fv -res 1.9x2.5 -pergro -spmd -nosmp

Namelist for the control runs:

% build-namelist \
  -namelist "&camexp nsrest=0 nelapse=-2 mss_irt=0 nrefrq=0 \
     nhtfrq=1 ndens=1 mfilt=145 hfilename_spec='h%t.nc' \
     empty_htapes=.true. fincl1='T:I','PS:I' aqua_planet=.true. /"

For the run that adds a perturbation to the initial temperature field
add the namelist variable "pertlim=1.e-14" to the above namelist.