<div dir="ltr">Dear NCL/NCARg Community,<div>I have sigma level temperature, specific humidity, and zonal and meridional wind components along with surface pressure. I wish to interpolate this data on prescribed pressure (standard 17) levels. I am using NCL's vinth2p function as</div><div><br></div><div> uap = vinth2p(ua_01,hyam,hybm,plevs,ps_01,1,1000,1,True)</div><div><br></div><div>where uap = Zonal wind at pressure level </div><div> ua_01 = Zonal wind at sigma level</div><div> ps_01 = Surface pressure in hPa</div><div> plevs = (/10,20, 30, 50, 70, 100, 150, 200 \</div><div> , 250, 300, 400, 500, 600, 700, 850, 925, 1000/)*1.0</div><div> hyam = fspan(0.,0.,18)<br></div><div> hybm = sigma<br></div><div><br></div><div>My results look fine over most parts of ocean, however, over land values are too high for 1000hPa zonal winds, especially over the mountaineous regions with low surface pressure, which is expected but How can I get that fixed while interpolating, I have used last argument of vinth2p function TRUE and FALSE both, but no improvement. </div><div>I am attaching two picture files one showing surface pressure and other depicting zonal wind at 1000 hPa interpolated using above function. </div><div>Any help/suggestion is greatly appreciated. </div><div>Many Thanks</div><div>Best</div><div><br clear="all"><div><div class="gmail_signature">Akhilesh <br>Center for Ocean-Atmospheric Prediction Studies<br>The Florida State University<br>2000 Levy Av, Building A, Room 252<br>Tallahassee FL 32310<br>Phone: (850) 645-0665<br>Fax: (850) 644-4841<br><a href="http://coaps.fsu.edu/akhilesh-mishra" target="_blank">http://coaps.fsu.edu/akhilesh-mishra</a> <<a href="http://coaps.fsu.edu/akhilesh-mishra" target="_blank">http://coaps.fsu.edu/akhilesh-mishra</a>><br><br></div></div>
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