[MITgcm-support] What is the demand for bathyFile ?

[Martin Losch]

brainf,

remember the cfl-criterium: velocity*timestep/gridspacing
When you decrease the grid spacing you have to decrease your time  
step. Also, if you expect (or observe) large velocities, you need to  
decrease your time step.
the monitor package also spits out advcfl_uvel_max etc. which is the  
above cfl-number.

btw, you can use deltaT=1200. for synchronous time stepping and  
comment out  deltaTtracer/clock/mom in your data.

more thing to try:
try turning off tauCD/useCDscheme

your hFacMin=.05 may be too small (not sure)

do you use useGMredi=.true. in data.pkg? if not you need some  
horizontal diffusion (diffKzT/S)

check your forcing (if you have any).

Martin

On 1 Nov 2006, at 03:03, Brainf wrote:

> Dear mitgcm,
>     I want to simulate my 0.25*0.25 degree (100x80x24 grid) example  
> base on Global Ocean Simulation at 4 Resolution, but something  
> wrong happend.  Does some demand for the bathyFile ? Example the  
> bathyfile must smooth enjoyably or some other demand?
>    I generate my bathy file from ETOP5, and the corresponding  
> hydrogThetaFile ,hydrogSaltFile from Levitus.
>     Of course ,I edit  the SIZE.h file and compiled it successed
> ...............//my size.h//.........
>      PARAMETER (
>      &           sNx =  50,
>      &           sNy =  40,
>      &           OLx =   2,
>      &           OLy =   2,
>      &           nSx =   2,
>      &           nSy =   1,
>      &           nPx =   1,
>      &           nPy =   1,
>      &           Nx  = sNx*nSx*nPx,
>      &           Ny  = sNy*nSy*nPy,
>      &           Nr  =  24)
> .....///...............................
>
> But I run it when "%MON time_tsnumber = 3", it say errors:
>    SOLUTION IS HEADING OUT OF BOUNDS: tMin,tMax=  -1.900E+00    
> 1.558E+04
> MON_SOLUTION: STOPPING CALCULATION
>  S/R EEDIE: Only     0 threads have completed,     1 are expected  
> for this confi
> guration!
>
>  Possibly you have different setenv PARALLEL and nThreads?
> STOP MON_SOLUTION: STOPPED DUE TO EXTREME VALUES OF SOLUTION  
> statement executed
>
> ///////////// and my data file//////////////
> # ====================
> # | Model parameters |
> # ====================
> #
> # Continuous equation parameters
>  &PARM01
>  tRef = 24*20.,
>  sRef = 24*35.,
>  viscAr=1.E-3,
>  viscAh=5.E5,
>  diffKhT=0.0,
>  diffKrT=3.E-5,
>  diffKhS=0.0,
>  diffKrS=3.E-5,
>  rhonil=1035.,
>  gravity=9.81,
>  eosType = 'JMD95Z',
>  ivdc_kappa=100.,
>  implicitDiffusion=.TRUE.,
>  useOldFreezing=.TRUE.,
>  useRealFreshWaterFlux=.TRUE.,
>  useCDscheme=.TRUE.,
>  useNHMTerms=.TRUE.,
> # turn on looped cells
>  hFacMin=.05,
>  hFacMindr=50.,
> # set precision of data files
>  readBinaryPrec=32,
>  &
>
> # Elliptic solver parameters
>  &PARM02
>  cg2dMaxIters=500,
>  cg2dTargetResidual=1.E-13,
>  &
>
> # Time stepping parameters
>  &PARM03
>  nIter0 =      0,
>  nTimeSteps = 1000,
> # 100 years of integration will yield a reasonable flow field
> # startTime  =          0.,
> # endTime    = 3110400000.,
>  deltaTmom = 1200.0,
>  tauCD =     321428.,
>  deltaTtracer= 1200.0,
>  deltaTClock = 1200.0,
> # if you are using a version later than checkpoint45d on the main  
> branch
> # you can uncomment the following line and increase the time step
> # deltaTtracer and deltaTClock to 172800.0 as well to speed up the
> # asynchronous time stepping
> # deltaTfreesurf = 172800.0,
>  abEps = 0.1,
>  pChkptFreq= 311040000.,
> # dumpFreq=   311040000.,
> # dumpFreq=   86400.,
>  dumpFreq=   43200.,
>  taveFreq=   311040000.,
>  taveFreq=   864000.,
> #monitorFreq=31104000.,
>  monitorFreq=1.,
> # 2 months restoring timescale for temperature
>  tauThetaClimRelax =  5184000.0,
> # 6 months restoring timescale for salinity
>  tauSaltClimRelax = 15552000.0,
>  periodicExternalForcing=.TRUE.,
>  externForcingPeriod=2592000.,
>  externForcingCycle=31104000.,
>  &
>
> # Gridding parameters
>  &PARM04
>  usingCartesianGrid=.FALSE.,
>  usingSphericalPolarGrid=.TRUE.,
>  delR= 10., 10., 10., 20., 25.,
>        25., 25., 25., 50., 50.,
>        50., 100., 100., 100., 100.,
>        100., 100., 100., 100., 100.,
>        100., 100., 150., 250.,
>  phiMin=5.,
>  thetaMin=105.,
>  dySpacing=0.25,
>  dxSpacing=0.25,
>  &
>
> # Input datasets
>  &PARM05
>  bathyFile=      'fc_dixing100x80x24.bin',
>  hydrogThetaFile='fc_t_100x80x24.bin',
>  hydrogSaltFile= 'fc_s_100x80x24.bin',
>  &
>  ////////////////////////////end///////////
>
> I will upload my  bathyFile at next mail if you want test it.
>
> Best regards.
>
> Brainf
> brainf at 163.com
> 2006-11-01
>
>
> _______________________________________________
> MITgcm-support mailing list
> MITgcm-support at mitgcm.org
> http://mitgcm.org/mailman/listinfo/mitgcm-support