<div dir="ltr"><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div>Dear NCL-experts,</div><div><br></div><div>I saw this function/tutorial for calculating the Potential vorticity from the NCL webpage.</div><div><br></div><div><a href="https://www.ncl.ucar.edu/Applications/pot_vort.shtml#:~:text=There%20are%20two%20potential%20vorticity,static%20stability%20and%20potential%20temperature">https://www.ncl.ucar.edu/Applications/pot_vort.shtml#:~:text=There%20are%20two%20potential%20vorticity,static%20stability%20and%20potential%20temperature</a>.<br></div><div><br></div><div>I would like to compute for the Potential Vorticity Tendency (PVT) on an isobaric level and global rectilinear grid reanalysis.</div><div><br></div><div>According to the attached file, PVT can be decomposed into </div><div>PVT= B* [ horizontal Advection + vertical advection + diabatic heating + friction ]</div><div><br></div><div>I can compute for the horizontal advection using this: <a href="https://www.ncl.ucar.edu/Document/Functions/Contributed/advect_variable.shtml">https://www.ncl.ucar.edu/Document/Functions/Contributed/advect_variable.shtml</a></div><div><br></div><div>My problem is how to calculate the diabatic heating here. Any suggestions on how I can do this in NCL?</div><div><br></div><div>-Lyndz</div><div><br></div><div><br></div></div></div></div></div></div></div></div></div></div></div>