SOS : kuroshio in east china sea

[zhang_1988]

Dear everyone
recently, i am working on simulating kuroshio
below is my setting


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Physical Parameters, Grid: 01
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6.0000E+01 nl_tnu2(01) NLM Horizontal, harmonic mixing coefficient(m2/s) for tracer 01: temp
6.0000E+01 nl_tnu2(02) NLM Horizontal, harmonic mixing coefficient(m2/s) for tracer 02: salt
6.0000E+01 nl_visc2 NLM Horizontal, harmonic mixing coefficient(m2/s) for momentum.
F LuvSponge Turning OFF sponge on horizontal momentum.
F LtracerSponge(01) Turning OFF sponge on tracer 01: temp
F LtracerSponge(02) Turning OFF sponge on tracer 02: salt
1.0000E-06 Akt_bak(01) Background vertical mixing coefficient (m2/s)for tracer 01: temp
1.0000E-06 Akt_bak(02) Background vertical mixing coefficient (m2/s)for tracer 02: salt
1.0000E-05 Akv_bak Background vertical mixing coefficient (m2/s)for momentum.
5.0000E-06 Akk_bak Background vertical mixing coefficient (m2/s)for turbulent energy.
5.0000E-06 Akp_bak Background vertical mixing coefficient (m2/s)for turbulent generic statistical field.
3.000 gls_p GLS stability exponent.
1.500 gls_m GLS turbulent kinetic energy exponent.
-1.000 gls_n GLS turbulent length scale exponent.
7.6000E-06 gls_Kmin GLS minimum value of turbulent kinetic energy.
1.0000E-12 gls_Pmin GLS minimum value of dissipation.
5.4770E-01 gls_cmu0 GLS stability coefficient.
1.4400E+00 gls_c1 GLS shear production coefficient.
1.9200E+00 gls_c2 GLS dissipation coefficient.
-4.0000E-01 gls_c3m GLS stable buoyancy production coefficient.
1.0000E+00 gls_c3p GLS unstable buoyancy production coefficient.
1.0000E+00 gls_sigk GLS constant Schmidt number for TKE.
1.3000E+00 gls_sigp GLS constant Schmidt number for PSI.
1400.000 charnok_alpha Charnok factor for Zos calculation.
0.500 zos_hsig_alpha Factor for Zos calculation using Hsig(Awave).
0.250 sz_alpha Factor for Wave dissipation surface tke flux .
100.000 crgban_cw Factor for Craig/Banner surface tke flux.
3.0000E-04 rdrg Linear bottom drag coefficient (m/s).
3.0000E-03 rdrg2 Quadratic bottom drag coefficient.
2.0000E-02 Zob Bottom roughness (m).
2.0000E-02 Zos Surface roughness (m).
2 Vtransform S-coordinate transformation equation.
4 Vstretching S-coordinate stretching function.
2.0000E+00 theta_s S-coordinate surface control parameter.
1.0000E-01 theta_b S-coordinate bottom control parameter.
10.000 Tcline S-coordinate surface/bottom layer width (m) usedin vertical coordinate stretching.
3.0000E+01 Tnudg(01) Nudging/relaxation time scale (days)for tracer 01: temp
3.0000E+01 Tnudg(02) Nudging/relaxation time scale (days)for tracer 02: salt
3.0000E+01 Znudg Nudging/relaxation time scale (days)for free-surface.
3.0000E+01 M2nudg Nudging/relaxation time scale (days)for 2D momentum.
3.0000E+01 M3nudg Nudging/relaxation time scale (days)for 3D momentum.
0.0000E+00 obcfac Factor between passive and activeopen boundary conditions.
F VolCons(1) NLM western edge boundary volume conservation.
F VolCons(2) NLM southern edge boundary volume conservation.
F VolCons(3) NLM eastern edge boundary volume conservation.
F VolCons(4) NLM northern edge boundary volume conservation.
14.000 T0 Background potential temperature (C) constant.
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my simulate area :

simulate area

simulate area.png (14.8 KiB) Viewed 2773 times

grid size is 5'*5'
Lateral Boundary Condition Type
LBC(isFsur) == Cha Cha Cha Cha ! free-surface
LBC(isUbar) == Fla Fla Fla Fla ! 2D U-momentum
LBC(isVbar) == Fla Fla Fla Fla ! 2D V-momentum
LBC(isUvel) == RadNud RadNud RadNud RadNud ! 3D U-momentum
LBC(isVvel) == RadNud RadNud RadNud RadNud ! 3D V-momentum
LBC(isMtke) == Rad Rad Rad Rad ! mixing TKE
LBC(isTvar) == RadNud RadNud RadNud RadNud ! temperature
RadNud RadNud RadNud RadNud ! salinity
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Useing HYCOM reanalysis data to make initial conditions and bounday conditions

Wind force comes from NCEP

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Here comes focus ; simulate for two years ;The outcome is some kind driving me crazy

the surface flow :

surfrce.rar

surface flow

(25.89 MiB) Downloaded 342 times

flow at 200m level :

flow-200m.rar

flow at 200m level

(17.59 MiB) Downloaded 244 times

from all the graphs in the .rar, there are two annoying eddies sucking all the waters which i want them to flow through Okinawa trough out the trough .
And , i am trapped in this situation .

sos

SOS.jpg (7.76 KiB) Viewed 2773 times

Any advice would be appreciated sincerely
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[kate]

I am not familiar with the .rar file format. Your .png and your .jpg show up nicely, though.

0.0000E+00 obcfac Factor between passive and active open boundary conditions.

What does this mean? Your Tnudg and friends are set to 30 days for the outgoing timescale. I have my incoming timescale set to 3 days, so you'd need to set obcfac to 10 to get that (if that's what you want). Anyway, obcfac is meant to be larger than one, so that the nudging is stronger on inflow than outflow.

[zhang_1988]

Thanks kate .i will make a try with reducing the Tnudg and other nudge parameter.
In addition, May i have your opinion about the other parameters like nl_tnu1,nl_tnu2 and nl_visc2 setting to be 60 60 60 .

[kate]

For horizontal smoothing, the "right" values depend on grid spacing. All I know about it is here.

[xwbin]

I have a question about your theta_s,theta_b and Tcline.My model area is South China Sea,and I set the theta_s=7,theta_b=1 like the example in romswiki.I also set the Tcline=300 which in your model is 10.I couldn't tell whether my parameter setting is right or not.You and me have the same area like the western Pacific and Kuroshio.Can you give me some advise on these three parameters?
Looking forward to your reply.