[MITgcm-support] Thermal wind in ocean cause too large velocity?

[Chun-Yan Zhou]

Based on
The temperature difference in horizontal direction can cause large velocity because of thermal wind.
And I did a test where the initial temperature field changed form 20-13 degree along the X direction, no other forces are applied.
 Large velocity is expected, but the maximum velocity is 4m/s, and the minimum is -4m/s, most of  the velocity is around 1.5m/s. Is the velocity should be so large?
 Any suggestion is appreciated.
chunyan

# ====================
# | Model parameters |
# ====================
#
# Continuous equation parameters
 &PARM01
 tRef=20*20.,
 sRef=20*35.,
 viscAh=4.E-2,
 viscAz=4.E-2,
 no_slip_sides=.FALSE.,
 no_slip_bottom=.FALSE.,
 diffKhT=4.E-2,
 diffKzT=4.E-2,
 f0=0.E-4,
 beta=0.E-11,
 tAlpha=2.0E-4,
 sBeta =0.,
 tempAdvScheme=77,
 gravity=10.,
 rhoConst=1000.,
 rhoNil=1000.,
 heatCapacity_Cp=4000.,
#rigidLid=.TRUE.,
 implicitFreeSurface=.TRUE.,
#exactConserv=.TRUE.,
 eosType='LINEAR',
 nonHydrostatic=.TRUE.,
 saltStepping=.FALSE.,
 staggerTimeStep=.TRUE.,
 &

# Elliptic solver parameters
 &PARM02
 cg2dMaxIters=1000,
 cg2dTargetResidual=1.E-9,
 cg3dMaxIters=1000,
 cg3dTargetResidual=1.E-9,
 &

# Time stepping parameters
 &PARM03
 nIter0=0,
#endTime=43200.,
 nTimeSteps=21600,
 deltaT=10.,
 abEps=0.1,
 pChkptFreq=43200.,
 chkptFreq=7200.,
 dumpFreq=1800.,
 monitorFreq=600.,
 monitorSelect=1,
 monitorFreq=1.,
 &

# Gridding parameters
 &PARM04
 usingCartesianGrid=.TRUE.,
 dXspacing=100.,
 dYspacing=100.,
 delZ=50*20.,
 &

# Input datasets
 &PARM05
 hydrogThetaFile='T.bin',
 &
%%%%%%%%%%%gendata.m
var=zeros(100,100,50);
for i=1:100
    var(i,:,:)=20-0.07*(i-1);
end
fid=fopen('T.bin','w','b'); fwrite(fid,var,'real*4'); fclose(fid);



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