<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Dear Kai,<div class="">I already noticed that “problem”, since I worked many times both with the skewt function and the wf_cape_3d function using both model and radiosonde data. The simple answer is YES, depending on the interpolation that you choose you will likely have different results. I think this is related to the fact that, depending on how many points you have in the vertical, the routine that search LCL and LFC will compute a point maybe 300 or 500 m lower/higher and thus you will have a different value of CAPE since it is integrated in the whole column on a different moist adiabatic.. I suggest you to work with the number of interpolation points that give you the same answer that you get also with other software, that’s how I did…</div><div class=""><br class=""><div class="">
<div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><br class="Apple-interchange-newline">Guido Cioni</div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><a href="http://guidocioni.altervista.org" class="">http://guidocioni.altervista.org</a> </div>
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<br class=""><div><blockquote type="cite" class=""><div class="">On 24 Mar 2016, at 06:08, 姚凯 <<a href="mailto:ken3yao@126.com" class="">ken3yao@126.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div style="line-height: 1.7; font-size: 14px; font-family: Arial;" class=""><div style="line-height: 23.8px;" class=""><span lang="EN-US" class=""> </span><br class="webkit-block-placeholder"></div><p class="MsoNormal" style="line-height: 17.85pt;"><a name="_olk_signature" style="color: rgb(19, 129, 68);" class=""><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class="">Dear all:<o:p class=""></o:p></span></a></p><p class="MsoNormal" style="line-height: 17.85pt;"><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class=""> I’m Kai Yao, a graduate from Nanjing University. Recently, I’m doing some work about convection weather. Your ncl scripts are really helpful, and thanks for everything you have done.<o:p class=""></o:p></span></p><p class="MsoNormal" style="line-height: 17.85pt;"><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class=""> Now, I’m confused about the script that plots the Skew_T and the Cape index it calculates. I have a data containing pressure, height, temperature, </span><span lang="EN-US" style="font-size: 10pt; font-family: Arial, sans-serif; color: rgb(51, 51, 51); background-image: initial; background-attachment: initial; background-size: initial; background-origin: initial; background-clip: initial; background-position: initial; background-repeat: initial;" class="">dew point temperature</span>, wind speed and wind direction<span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class=""> of 28 levels from 1000hpa to 100hpa in TXT format. The plot shows that the cape index is about 2000, but when after the interpolation, I get the data of 901 levels from 1000hpa to 100hpa, then I redrew the plot, and it shows the cape index is about 800 which is much closer to the calculation from the micaps software.<o:p class=""></o:p></span></p><p class="MsoNormal" style="line-height: 17.85pt;"><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class=""> </span><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class="">I would like to know whether it is the vertical resolution that causes the difference. If so, what is the supposed vertical resolution and the best interpolation method when I want to know the real cape index?<o:p class=""></o:p></span></p><p class="MsoNormal" style="line-height: 17.85pt;"><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class=""> Looking forward to your reply<o:p class=""></o:p></span></p><p class="MsoNormal" style="line-height: 17.85pt;"><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class="">Best<o:p class=""></o:p></span></p><p class="MsoNormal" style="line-height: 17.85pt;"><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class="">Yours<o:p class=""></o:p></span></p><p class="MsoNormal" style="line-height: 17.85pt;"><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class="">Kai Yao <o:p class=""></o:p></span></p><div class=""><span lang="EN-US" style="font-size: 10.5pt; font-family: Arial, sans-serif;" class=""><br class=""></span></div></div><br class=""><br class=""><span title="neteasefooter" class=""><div class=""> <br class="webkit-block-placeholder"></div></span>_______________________________________________<br class="">ncl-talk mailing list<br class=""><a href="mailto:ncl-talk@ucar.edu" class="">ncl-talk@ucar.edu</a><br class="">List instructions, subscriber options, unsubscribe:<br class="">http://mailman.ucar.edu/mailman/listinfo/ncl-talk<br class=""></div></blockquote></div><br class=""></div></body></html>