<div dir="ltr">Good morning, <div><br></div><div>Thank you very much. There is only one doubt left unanswered: the <b>advect_function </b>requires a <u>Gaussian, regular o fixed grid</u>, but not <u>rectilinear</u>. Is there any relation between them?</div><div><br></div><div>Regards, </div><div>Lara</div></div><div class="gmail_extra"><br><div class="gmail_quote">2018-05-21 19:21 GMT+02:00 Dennis Shea <span dir="ltr"><<a href="mailto:shea@ucar.edu" target="_blank">shea@ucar.edu</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>ESMF 37 was <br>(a) interpolating u and v onto a rectilinear grid; <br>(b) calculating divergence using uv2dv_cfd which requires u and v to be on a rectilinear grid; <br>(c) interpolating the derived divergence on a rectilinear grid back onto the original WRF grid<br><br>---<br></div>In your case:<br><div><br>[1] Interpolate the WRF u, v and relative vorticity to a rectilinear grid with as fine [or finer] resoultion as the WRF grid<br></div><div>[2] Use 'advect_variable' on the rectilinear grid<br>[3] interpolate the advected quantity on the rectilinear grid back onto the original WRF grid<br><br>---<br></div><div>Caveat: Technically, on a sphere, u and v must be interpolated together using the 'rotation' angle.<br></div><div>Why? because the new location has a 'slightly' different orientation relative to the pole(s) <br></div><div><br> unew = u*cos(rot) - v*sin(rot) <br> vnew = u*sin(rot) + v*cos(rot)<br><br></div><div>The above approach, independently interpolating u and v ignores the rotation. It is assumed to be very small.<br><br> <br></div><div><br></div></div><div class="HOEnZb"><div class="h5"><div class="gmail_extra"><br><div class="gmail_quote">On Mon, May 21, 2018 at 3:45 AM, Lara Quitián Hernández <span dir="ltr"><<a href="mailto:laraquitianhernandez@gmail.com" target="_blank">laraquitianhernandez@gmail.<wbr>com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>Good morning,</div><div><br></div>Thank you so much. Unfortunately, I have some doubts. <div><br></div><div>1.- I have read the information for Example 37 but I do not understand the need of computing the divergence ("uv2dv_cfd"). I just need my variables on a Gaussian, regular o fixed grid in order to apply the <b>advect_variable</b> function</div><div>2.- I need to convert my curvilinear WRF grid to a Gaussian, regular o fixed grid. However, in both Examples (29a and 37) a regrid from a WRF grid to a rectilinear grid is carried out. Are those grids (Gaussian, regular o fixed grid) also rectilinear grids?</div><div>3.-Do I need to regrid back to the WRF curvilinear grid as it is done in both examples?</div><span><div><br></div><div>Thanks in advance. </div><div><br></div><div>Regards, </div><div>Lara</div><div><br></div><div><br></div></span></div><div class="m_3603104038903624767HOEnZb"><div class="m_3603104038903624767h5"><div class="gmail_extra"><br><div class="gmail_quote">2018-05-20 1:10 GMT+02:00 Dennis Shea <span dir="ltr"><<a href="mailto:shea@ucar.edu" target="_blank">shea@ucar.edu</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div><div><div><div><div>NCL has no builtin function to advect a field (eg: vorticity) on a curvilinear grid (eg: your WRF Grid)..<br></div>Maybe ask wrfhelp?<br><br>===<br></div>That said<br><br><a href="https://www.ncl.ucar.edu/Applications/ESMF.shtml" target="_blank">https://www.ncl.ucar.edu/Appli<wbr>cations/ESMF.shtml</a><br></div>Example 29a<br></div><div>or, maybe better,<br></div><div>Example 37<br></div><div><br></div>outlines a method that might be used for your needs.<br><br></div>===<br></div>Good luck<br><div><br></div></div><div class="m_3603104038903624767m_-1059488269469768275HOEnZb"><div class="m_3603104038903624767m_-1059488269469768275h5"><div class="gmail_extra"><br><div class="gmail_quote">On Wed, May 16, 2018 at 7:40 AM, Lara Quitián Hernández <span dir="ltr"><<a href="mailto:laraquitianhernandez@gmail.com" target="_blank">laraquitianhernandez@gmail.co<wbr>m</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Hello, <div><br></div><div>Thank you. In the case of calculating the horizontal advection for <b>vorticity</b>, it would be better to use the direct WRF variable ( vo = wrf_user_getvar(a,"<b class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329m_-4307035958762947733gmail-">avo</b>",-1)) or define it via different functions: <a href="https://www.ncl.ucar.edu/Applications/vort.shtml" target="_blank">https://www.ncl.uca<wbr>r.edu/Applications/vort.shtml</a></div><div><br></div><div>The only example in the link defines the Vorticity like this:</div><div><pre style="color:rgb(0,0,0);font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;word-spacing:0px;text-decoration-style:initial;text-decoration-color:initial;word-wrap:break-word;white-space:pre-wrap">;*****************************<wbr>*******************
; calculate vorticity on a Gaussian Grid
; scale for visual convenience
;*****************************<wbr>*******************
scale = 1.e05
vrt = u ; retain coordinates
vrt = uv2vrG_Wrap(u,v) * scale
vrt@long_name = "vorticity"
vrt@units = "scaled"</pre></div><div><br></div><div>However, my simulations are generated on a Lambert Conformal grid projection, not Gaussian one. Does this change the procedure to calculate it?</div><div><br></div><div>Regards, </div><span class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329HOEnZb"><font color="#888888"><div>Lara</div></font></span></div><div class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329HOEnZb"><div class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329h5"><div class="gmail_extra"><br><div class="gmail_quote">2018-05-16 14:28 GMT+02:00 Dennis Shea <span dir="ltr"><<a href="mailto:shea@ucar.edu" target="_blank">shea@ucar.edu</a>></span>:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div>Maybe:<br><br><a href="https://www.ncl.ucar.edu/Document/Functions/Contributed/advect_variable.shtml" target="_blank">https://www.ncl.ucar.edu/Docum<wbr>ent/Functions/Contributed/adve<wbr>ct_variable.shtml</a><br><br></div>'x' would be vorticity<br><br></div>Good Luck<br></div><div class="gmail_extra"><br><div class="gmail_quote"><div><div class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329m_-4307035958762947733h5">On Wed, May 16, 2018 at 4:01 AM, Lara Quitián Hernández <span dir="ltr"><<a href="mailto:laraquitianhernandez@gmail.com" target="_blank">laraquitianhernandez@gmail.co<wbr>m</a>></span> wrote:<br></div></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329m_-4307035958762947733h5"><div dir="ltr">Good morning, <div><br></div><div>I would like to know if there is a possibility of calculating the Vorticity Advection with NCL.</div><div><br></div><div>Thanks in advance.</div><div><br></div><div>Regards, </div><span class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329m_-4307035958762947733m_2745945185124896099HOEnZb"><font color="#888888"><div>Lara</div><div><br clear="all"><div><br></div>-- <br><div class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329m_-4307035958762947733m_2745945185124896099m_-1448946543173881759gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><img src="https://docs.google.com/uc?export=download&id=0B5glieJcogGocjdGWHA3NWIwdmc&revid=0B5glieJcogGocU45NUpENzV4UWhCWk9tb1ZGdXB5MEtGYjJjPQ"><br><div><font color="#000000"><br></font></div><div><b><font color="#000000"><span style="font-size:12.8px">Lara Quitián Hernández, </span></font><span style="color:rgb(0,0,0);font-size:12.8px">PhD Student</span></b><font color="#000000"><b><br style="font-size:12.8px"></b><span style="font-size:12.8px">Departamento de Física de la Tierra, Astronomía y Astrofísica</span><br style="font-size:12.8px"><span style="font-size:12.8px">Facultad de Ciencias Físicas</span><br style="font-size:12.8px"><span style="font-size:13px"><a href="https://maps.google.com/?q=Ciudad+Universitaria,+Plaza+Ciencias,+1+28040+Madrid.+Spain&entry=gmail&source=g" target="_blank">Ciudad Universitaria, Plaza Ciencias, 1</a></span></font></div><div><font color="#000000"><span style="font-size:12.8px"><a href="https://maps.google.com/?q=Ciudad+Universitaria,+Plaza+Ciencias,+1+28040+Madrid.+Spain&entry=gmail&source=g" target="_blank">28040 Madrid. Spain</a></span><br style="font-size:12.8px"><span style="font-size:12.8px">Email: </span><a href="mailto:mlunar@aemet.es" style="font-size:12.8px" target="_blank">lquitian@ucm.es</a><br style="font-size:12.8px"></font><br></div></div></div></div></div>
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</blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="m_3603104038903624767m_-1059488269469768275m_-4196797236910994329m_-4307035958762947733gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><img src="https://docs.google.com/uc?export=download&id=0B5glieJcogGocjdGWHA3NWIwdmc&revid=0B5glieJcogGocU45NUpENzV4UWhCWk9tb1ZGdXB5MEtGYjJjPQ"><br><div><font color="#000000"><br></font></div><div><b><font color="#000000"><span style="font-size:12.8px">Lara Quitián Hernández, </span></font><span style="color:rgb(0,0,0);font-size:12.8px">PhD Student</span></b><font color="#000000"><b><br style="font-size:12.8px"></b><span style="font-size:12.8px">Departamento de Física de la Tierra, Astronomía y Astrofísica</span><br style="font-size:12.8px"><span style="font-size:12.8px">Facultad de Ciencias Físicas</span><br style="font-size:12.8px"><span style="font-size:13px"><a href="https://maps.google.com/?q=Ciudad+Universitaria,+Plaza+Ciencias,+1+28040+Madrid.+Spain&entry=gmail&source=g" target="_blank">Ciudad Universitaria, Plaza Ciencias, 1</a></span></font></div><div><font color="#000000"><span style="font-size:12.8px"><a href="https://maps.google.com/?q=Ciudad+Universitaria,+Plaza+Ciencias,+1+28040+Madrid.+Spain&entry=gmail&source=g" target="_blank">28040 Madrid. Spain</a></span><br style="font-size:12.8px"><span style="font-size:12.8px">Email: </span><a href="mailto:mlunar@aemet.es" style="font-size:12.8px" target="_blank">lquitian@ucm.es</a><br style="font-size:12.8px"></font><br></div></div></div></div></div>
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</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="m_3603104038903624767m_-1059488269469768275gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><img src="https://docs.google.com/uc?export=download&id=0B5glieJcogGocjdGWHA3NWIwdmc&revid=0B5glieJcogGocU45NUpENzV4UWhCWk9tb1ZGdXB5MEtGYjJjPQ"><br><div><font color="#000000"><br></font></div><div><b><font color="#000000"><span style="font-size:12.8px">Lara Quitián Hernández, </span></font><span style="color:rgb(0,0,0);font-size:12.8px">PhD Student</span></b><font color="#000000"><b><br style="font-size:12.8px"></b><span style="font-size:12.8px">Departamento de Física de la Tierra, Astronomía y Astrofísica</span><br style="font-size:12.8px"><span style="font-size:12.8px">Facultad de Ciencias Físicas</span><br style="font-size:12.8px"><span style="font-size:13px">Ciudad Universitaria, <a href="https://maps.google.com/?q=Plaza+Ciencias,+1+28040+Madrid.+Spain&entry=gmail&source=g" target="_blank">Plaza Ciencias, 1</a></span></font></div><div><font color="#000000"><span style="font-size:12.8px"><a href="https://maps.google.com/?q=Plaza+Ciencias,+1+28040+Madrid.+Spain&entry=gmail&source=g" target="_blank">28040 Madrid. Spain</a></span><br style="font-size:12.8px"><span style="font-size:12.8px">Email: </span><a href="mailto:mlunar@aemet.es" style="font-size:12.8px" target="_blank">lquitian@ucm.es</a><br style="font-size:12.8px"></font><br></div></div></div></div></div>
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</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><img src="https://docs.google.com/uc?export=download&id=0B5glieJcogGocjdGWHA3NWIwdmc&revid=0B5glieJcogGocU45NUpENzV4UWhCWk9tb1ZGdXB5MEtGYjJjPQ"><br><div><font color="#000000"><br></font></div><div><b><font color="#000000"><span style="font-size:12.8px">Lara Quitián Hernández, </span></font><span style="color:rgb(0,0,0);font-size:12.8px">PhD Student</span></b><font color="#000000"><b><br style="font-size:12.8px"></b><span style="font-size:12.8px">Departamento de Física de la Tierra, Astronomía y Astrofísica</span><br style="font-size:12.8px"><span style="font-size:12.8px">Facultad de Ciencias Físicas</span><br style="font-size:12.8px"><span style="font-size:13px">Ciudad Universitaria, Plaza Ciencias, 1</span></font></div><div><font color="#000000"><span style="font-size:12.8px">28040 Madrid. Spain</span><br style="font-size:12.8px"><span style="font-size:12.8px">Email: </span><a href="mailto:mlunar@aemet.es" style="font-size:12.8px" target="_blank">lquitian@ucm.es</a><br style="font-size:12.8px"></font><br></div></div></div></div></div>
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