[MITgcm-support] Strips on the surface

[Kateryna Terletska]

Dear MITgcm users,

I run MIT model to investigate 3D internal seiches in elongated lakes. I
run parallel version of MIT on 32 nodes.
But I obtain some strange  strips on the surface (picture is in the
attachment). Increasing of viscosity and decreasing of dt didn't worked.
Also some vertical strips occur when seiches undergoes strong interaction
with the bottom topography (it looks like instability). Picture of
temperature in vertical cross section is also attached.
Can you give some ideas to overcome this problem?

Thanks
Kateryna.


My data file is

# ====================
# | Model parameters |
# ====================
#
# Continuous equation parameters
 &PARM01
 tRef=100*20.,
 sRef=100*0.,
 viscAh=8.E-4,
 viscAz=8.E-4,
 bottomDragLinear=0.E-4,
 no_slip_sides=.FALSE.,
 no_slip_bottom=.FALSE.,
 diffKhT=8.E-4,
 diffKzT=8.E-4,
 diffKhS=8.E-4,
 diffKzS=8.E-4,
 f0=0.e-4,
 beta=0.E-11,
 eosType='LINEAR',
 rigidLid=.FALSE.,
 implicitFreeSurface=.TRUE.,
 gravity =9.81,
 nonHydrostatic=.TRUE.,
 readBinaryPrec=64,
 staggerTimeStep=.TRUE.,
 hFacMin= 0.001,
#- not safe to use globalFiles in multi-processors runs
 useSingleCpuIO =.TRUE.,
 tempAdvScheme=77,
 &

# Elliptic solver parameters
 &PARM02
 cg2dMaxIters=300,
 cg2dTargetResidual=1.E-13,
 cg3dMaxIters=20,
 cg3dTargetResidual=1.E-8,
 &

# Time stepping parameters
 &PARM03
 nIter0=0,
 nTimeSteps=900000,
 deltaT=0.005
 abEps=0.1,
 pChkptFreq=50.,
 chkptFreq=0.0,
 dumpFreq=20.,
 monitorSelect=2,
 monitorFreq=1.,
 &

# Gridding parameters
 &PARM04
 usingCartesianGrid=.TRUE.,
 delX=1000*5.0,
 delY=200*5.0,
# dYspacing=5,
 delZ=100*0.3,
 &

# Input datasets
 &PARM05
 bathyFile='topog.lake',
 hydrogThetaFile='Temp.init',
 &
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