[MITgcm-support] seaice anomalous advection in doubly periodic domain

[Jean Mensa]

Hello list,
I am trying to setup an idealized ocean simulation with sea ice using the
SEAICE package. The domain is a doubly periodic box (400km by 200km) which
I force with a semi-idealized ECMWF forcing. Forcing is periodic in time
(and space) and seems to generate the expected seasonal cycle of ice
thickness and concentration. Nevertheless there seems to be something wrong
with the ice advection.

1 - ice velocities follow wind forcing for a while, and then, as ice starts
growing (not sure if that is a coincidence), they stop being affected by
wind forcing and transition to steady state as if purely driven by ice
inertia. Ice moves at a reasonable speed, it just goes to steady state. I
am not sure whether this is a numerical/physical problem or an consequence
of the doubly periodic setup.

2 - ice growth shows anomalous growth at the boundaries of the partitioning
tiles. This results in a distinguishable thickness anomaly. Currently I use
the same advection scheme than for tracers, a 3-rd order flux-limiter (33),
and the problem persists when switching to a smaller stencil.

I am not sure whether the two problems are linked or not. The second one
looks like a numerical issue but the first one could be due to my
particular setup.
Any idea on what's going on?
Thanks!

It follows my data and data.seaice files,

############# DATA

# Model parameters
# Continuous equation parameters
 &PARM01
 no_slip_bottom=.FALSE.,
 eosType='JMD95P',
 diffKhT=0,
 diffKzT=0,
 rotationPeriod=86400.,
 beta=0,
 f0=1.4e-4,
 gravity=9.81,
 rigidLid=.FALSE.,
 implicitFreeSurface=.TRUE.,
 implicitViscosity = .TRUE.,
 implicitDiffusion = .TRUE.,
 tempAdvScheme=33,
 saltAdvScheme=33,
 viscC2Leith=1.0,
 staggerTimeStep=.TRUE.,
 nonHydrostatic=.FALSE.,
 readBinaryPrec=64,
 &
# Elliptic solver parameters
 &PARM02
 cg2dMaxIters=1000,
 cg2dTargetResidual=1.E-7,
 &
# Time stepping parameters
 &PARM03
 endTime=189216000,
 deltaTmom=240.0,
 deltaTtracer=240.0,
 abEps=0.1,
 pChkptFreq=8640000.0,
 chkptFreq=1728000.0,
 dumpFreq=86400.,
 monitorFreq=864000.,
 forcing_In_AB = .FALSE.,
 pickupStrictlyMatch = .TRUE.,
 &

# Gridding parameters
 &PARM04
 usingCartesianGrid=.TRUE.,
 usingSphericalPolarGrid=.FALSE.,
 delX=400*1000,
 delY=200*1000,
 delZ=2, 2, 2, 2, 2, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 10, 10, 10,
10, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 30, 50, 50,
50, 50, 50,
 &

# Input datasets
 &PARM05
 bathyFile='topo.bin',
 hydrogThetaFile='theta_100_DP.bin',
 checkIniTemp=.FALSE.,
 hydrogSaltFile='salinity_100_DP.bin',
 uVelInitFile='u_100_DP.bin',
 vVelInitFile='v_100_DP.bin',
 &


############# DATA.SEAICE

 &SEAICE_PARM01
  SEAICEwriteState   = .TRUE.,
  SEAICEuseFlooding  = .TRUE.,
  SEAICE_EPS         = 1.E-8,
  SEAICE_area_floor  = 1.E-5,
  SEAICE_area_reg    = 0.15,
  SEAICE_hice_reg    = 0.10,
  IMAX_TICE = 6,
  SEAICE_availHeatFrac = 0.8,
  SEAICEuseDYNAMICS  = .TRUE.,
  HeffFile = 'ice_thick_S.bin',
  AreaFile = 'ice_fract_S.bin',
  SEAICEadvScheme    = 33,
  useHB87StressCoupling=.TRUE.,
 &

 &SEAICE_PARM03
 &
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mitgcm.org/pipermail/mitgcm-support/attachments/20151029/6523f5cb/attachment.htm>