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<p>Hi all,<br>
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<p>I am trying to setup a case of neutral boundary layer driven by a desired geostrophic wind. When I check the<span style="font-size:12pt"> </span><span style="font-size:12pt"><em>/test/em_les/Readme.les
</em>I find the following instruction</span><span style="font-size:12pt">:</span></p>
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<div><em>"To simulate a CBL with a mean wind, change the initial wind </em><span style="font-size:12pt"><em>profile in the input sounding. </em></span><span style="font-size:12pt"><em>When pert_coriolis= true is set in the namelist,
<strong>there is no </strong></em></span><span style="font-size:12pt"><em><strong>need to </strong></em></span><span style="font-size:12pt"><em><strong>include the geostrophic wind terms</strong> in the right-hand sides of </em></span><span style="font-size:12pt"><em>the
u and v equati</em></span><span style="font-size:12pt"><em>ons for LESs with non-zero geostrophic wind."</em></span><span style="font-size:12pt"> </span></div>
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<p>I fail to understand why the geostrophic term is not needed to be added here. From my understanding (and trial) <em style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:16px; background-color:rgb(255,255,255)">pert_coriolis= true</em> just turned <span style="font-size: 12pt;">on
the</span><span style="font-size: 12pt;"> Coriolis effect </span><span style="font-size: 12pt;">in the </span>simulation<span style="font-size: 12pt;">. But since the geostrophic forcing term should take the form of <em>Du/Dt =</em> <em>f(v-v_g), <em style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);">Dv/Dt
=</em><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);"> </span><em style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);">f(u-u_g)</em>
</em>in the momentum equation<em>, </em>I don't quite understand why this case <span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);">could</span> simulate a non-zero geostrophic wind without
adding any new term? What geostrophic wind speed did it specified here then?</span></p>
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<p>Thank you very much for your help.<br>
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<p>Regards,<br>
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<p>Mou Lin <br>
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