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<p>Hi Martin,</p>
<p><br>
</p>
<p>The verification expt you mentioned did not help me much.</p>
<p>Instead, I went to /pkg/mom_common,</p>
<p>1) I am currently using viscC2smag and a quick read on mom_calc_visc.F seems to suggest only the horizontal smag is implemented but not the vertical?</p>
<p>2) If I use smag3d, I find mom_w_smag_3d.F, so the vertical smag is implemented if smag3d is turned on?</p>
<p>3) What is the recommended value for smag3d? I cannot find much info on how to use smag3d. Any chance the manual may be updated with the code?</p>
<p><br>
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<p>Thanks</p>
<p><br>
</p>
<p>Yangxin<br>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> MITgcm-support <mitgcm-support-bounces@mitgcm.org> on behalf of Martin Losch <Martin.Losch@awi.de><br>
<b>Sent:</b> Monday, May 13, 2019 3:59:33 AM<br>
<b>To:</b> MITgcm Support<br>
<b>Subject:</b> Re: [MITgcm-support] vertical smagorinsky viscosity</font>
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<div class="PlainText">Hi Yangxin,<br>
<br>
1) I think that the manual is a little behind. It’s always a good idea to check model/inc/PARAMS.h to see, what parameter are actually available, because there recent changes are more like documented that in the documentation. I find this:<br>
C useSmag3D :: Use isotropic 3-D Smagorinsky<br>
C smag3D_coeff :: Isotropic 3-D Smagorinsky coefficient (-)<br>
and when I grep for smag3D_coeff in the verification experiment I find this:<br>
tutorial_deep_convection/input.smag3d<br>
so maybe you can start there and see how it works.<br>
<br>
2) viscosity and diffusivity are independent and viscC?Smag only affects the viscosity. Unless you set the diffusivity explicitly, it is zero.<br>
<br>
Martin<br>
> On 10. May 2019, at 17:39, Yangxin He <y67he@uwaterloo.ca> wrote:<br>
> <br>
> Hi there,<br>
> <br>
> 1) The manual says the vertical smag viscosity is not implemented, I wanna confirm if this is still the case? If MITgcm has the vertical smag set up now, is there a way to turn it off?<br>
> 2) When I only use the smag harmonic viscosity, i.e. viscC2Smag, does it do anything to the diffusivity? is the diffusivity 0?<br>
> <br>
> thanks.<br>
> <br>
> Yangxin<br>
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