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Hi Jiatong,<br>
<br>
You mentioned <br>
The white area is the NAN value output from Mitgcm.<br>
<br>
What values are these? T/U/V? Why are they NaN but not 0?<br>
<br>
Yangxin
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> MITgcm-support <mitgcm-support-bounces@mitgcm.org> on behalf of JIATONG <jiatong@radi.ac.cn><br>
<b>Sent:</b> Friday, December 27, 2019 1:50:30 AM<br>
<b>To:</b> mitgcm-support<br>
<b>Subject:</b> Re: [MITgcm-support] noise near the bottom</font>
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<div><span></span>Hi Yangxin,</div>
<div>Thank you very much. I agree that the<span style="color: rgb(0, 0, 0); font-size: 10.5pt; line-height: 1.5; background-color: rgba(0, 0, 0, 0);"> noise could be a combination of the turbulence and the grid scale noise. Because when I change</span><span style="color: rgb(0, 0, 0); font-size: 10.5pt; line-height: 1.5; background-color: rgba(0, 0, 0, 0);"> the resolution,
some noises are removed while others are still there.</span></div>
<div><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;">The red line in the picture below is the actual topography that I put into the model. The dz is set to 5m. The white area is the NAN value output from Mitgcm. </span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;">I
think that the </span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;">topograohy</span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;"> is not rough.</span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;"> </span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;">I
have checked the MITgcm manul, it means when </span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;">hFacMin is set to 0.1, the actual thickness of the bottom cell
</span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;">can cover a range of discrete values 0.5m apart from 0.5m to 5m depending on the </span><span style="font-size: 10.5pt; line-height: 1.5; background-color: transparent;">value
of the bottom depth (in bathyFile).So in the MITGCM calculation, the </span><span style="color: rgb(0, 0, 0); font-size: 10.5pt; line-height: 1.5; background-color: rgba(0, 0, 0, 0);">accuracy of the </span><span style="color: rgb(0, 0, 0); font-size: 10.5pt; line-height: 1.5; background-color: rgba(0, 0, 0, 0);">bathymetry
in my model is up to 0.5m. Am I right? </span></div>
<div><img border="0" width="676.5" height="368" src="cid:_Foxmail.1@f548e940-2bb7-862d-3ebf-f6b5ddcfeb3d"></div>
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<div>JIATONG</div>
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