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<p class="MsoNormal"><span lang="EN-US">Dear MITgcm community,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I am running MITgcm in a rectangular basin with a single-hemisphere setup. However, I am encountering irregularities in both vertical and horizontal velocity fields near the basin boundaries (see attached figure).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Initially, I suspected insufficient horizontal viscosity. While increasing it to unrealistically high values reduced the issue, it did not resolve it entirely.
</span>I have also tested the following:<o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<ul style="margin-top:0cm" type="disc">
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Decreasing time-step,<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Using different advection schemes,<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Increasing horizontal diffusion,<o:p></o:p></span></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1"><span lang="EN-US">Increasing vertical viscosity.<o:p></o:p></span></li></ul>
<p class="MsoListParagraph"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">None of these approaches have fully addressed the problem. I have also reviewed studies using similar setups, but they do not report encountering this issue. Does anyone have insights into what might be causing this or
 suggestions for a fix? I have attached my data file and SIZE.h for reference.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Any help would be greatly appreciated.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Best regards,<br>
Elian<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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