<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">The best known tornado simulation has a small anti-cyclone on the side. The narrator describes it as “a rarely see anit-cyclone.” Having asked many time whether it ever has been seen, the answer seems to be “not yet.” Clearly the one in the visualization is an artifact from an imperfect model.<div class=""><br class=""></div><div class="">One other comment. It used to be the case that in computer graphics if something looked OK that was sufficient. That’s no longer true. With the present computer power in GPUs, pretty every special effect you see in a movie is a physically-based simulation. Recent game engines come pretty close to that too.</div><div class=""><br class=""></div><div class="">Ed<br class=""><div class="">
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div class="">_______________________</div><div class=""><br class="Apple-interchange-newline">Ed Angel<br class=""><br class=""></div><div class="">Founding Director, Art, Research, Technology and Science Laboratory (ARTS Lab)<br class="">Professor Emeritus of Computer Science, University of New Mexico<br class=""><br class="">1017 Sierra Pinon</div><div class="">Santa Fe, NM 87501<br class="">505-984-0136 (home)<span class="Apple-tab-span" style="white-space: pre; "> </span> <span class="Apple-tab-span" style="white-space: pre; "> </span><a href="mailto:angel@cs.unm.edu" class="">angel@cs.unm.edu</a></div><div class="">505-453-4944 (cell) <span class="Apple-tab-span" style="white-space: pre; "> </span><span class="Apple-tab-span" style="white-space: pre; "> </span><a href="http://www.cs.unm.edu/~angel" class="">http://www.cs.unm.edu/~angel</a><br class=""></div></span></span>
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<div><br class=""><blockquote type="cite" class=""><div class="">On May 13, 2020, at 9:44 PM, <<a href="mailto:thompnickson2@gmail.com" class="">thompnickson2@gmail.com</a>> <<a href="mailto:thompnickson2@gmail.com" class="">thompnickson2@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html; charset=utf-8" class=""><meta name="Generator" content="Microsoft Word 15 (filtered medium)" class=""><style class=""><!--
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</o:shapelayout></xml><![endif]--><div lang="EN-US" link="blue" vlink="purple" class=""><div class="WordSection1"><div class="MsoNormal">Frank, <o:p class=""></o:p></div><div class="MsoNormal">I think that was the one that depicted tornadoes as arising from a horizontal barrel roll being bulged upward in the middle and ultimately split into two vortexes, one clockwise one, counter. This idea does explain why sometimes a weak anti-cyclonic tornado often appear next to a main cyclonic one. But the idea did seem kind of rinky-dink to me. You are right, of course, I had no way to visit the math and evaluate it <o:p class=""></o:p></div><div class="MsoNormal"><o:p class=""> </o:p></div><div class="MsoNormal">Nick <o:p class=""></o:p></div><div class="MsoNormal"><o:p class=""> </o:p></div><div class="MsoNormal">Nicholas Thompson<o:p class=""></o:p></div><div class="MsoNormal">Emeritus Professor of Ethology and Psychology<o:p class=""></o:p></div><div class="MsoNormal">Clark University<o:p class=""></o:p></div><div class="MsoNormal"><a href="mailto:ThompNickSon2@gmail.com" class=""><span style="color:#0563C1" class="">ThompNickSon2@gmail.com</span></a><o:p class=""></o:p></div><div class="MsoNormal"><a href="https://wordpress.clarku.edu/nthompson/" class=""><span style="color:#0563C1" class="">https://wordpress.clarku.edu/nthompson/</span></a><o:p class=""></o:p></div><div class="MsoNormal"> <o:p class=""></o:p></div><div class="MsoNormal"><o:p class=""> </o:p></div><div class="MsoNormal"><o:p class=""> </o:p></div><div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in" class=""><div class="MsoNormal"><b class="">From:</b> Friam <<a href="mailto:friam-bounces@redfish.com" class="">friam-bounces@redfish.com</a>> <b class="">On Behalf Of </b>Frank Wimberly<br class=""><b class="">Sent:</b> Wednesday, May 13, 2020 9:31 PM<br class=""><b class="">To:</b> The Friday Morning Applied Complexity Coffee Group <<a href="mailto:friam@redfish.com" class="">friam@redfish.com</a>><br class=""><b class="">Subject:</b> Re: [FRIAM] PSC Tornado Visualization (2008) [720p] - YouTube<o:p class=""></o:p></div></div><div class="MsoNormal"><o:p class=""> </o:p></div><div class=""><div class="MsoNormal">The fluid dynamics model used for that visualization is based on first principles. Many years ago Nick was trying to figure out how tornadoes develop. I told him I thought this was pretty well understood and I asked Droegemeier for a paper. He sent one which I forwarded to Nick. It was full of advanced math. <o:p class=""></o:p></div><div class=""><div class="MsoNormal"><o:p class=""> </o:p></div></div><div class=""><div class="MsoNormal">Frank<o:p class=""></o:p></div><div class=""><div class="MsoNormal"><o:p class=""> </o:p></div><div class=""><div class="MsoNormal">---<br class="">Frank C. Wimberly<br class="">140 Calle Ojo Feliz, <br class="">Santa Fe, NM 87505<br class=""><br class="">505 670-9918<br class="">Santa Fe, NM<o:p class=""></o:p></div></div></div></div></div><div class="MsoNormal"><o:p class=""> </o:p></div><div class=""><div class=""><div class="MsoNormal">On Wed, May 13, 2020, 9:23 PM Marcus Daniels <<a href="mailto:marcus@snoutfarm.com" class="">marcus@snoutfarm.com</a>> wrote:<o:p class=""></o:p></div></div><blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in" class="" type="cite"><div class=""><div class=""><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Nick writes:<o:p class=""></o:p></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p class=""></o:p></p><p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">“The result looks so much like iconic tornado vids that we wannabee tornado chasers idolize that one suspects that the video was back constructed from that film, rather than developing organically from the physics.”<o:p class=""></o:p></p><div class="">Suppose the equations were extracted, or the behavior re-generated, from a deep neural net (or whatever automated machine learning thing), but nonetheless were predictive of other tornados. One might reasonably ask, “Who cares?”<o:p class=""></o:p></div><div class="">Marcus<o:p class=""></o:p></div></div></div><div class="MsoNormal">.-. .- -. -.. --- -- -..-. -.. --- - ... -..-. .- -. -.. -..-. -.. .- ... .... . ...<br class="">FRIAM Applied Complexity Group listserv<br class="">Zoom Fridays 9:30a-12p Mtn GMT-6 <a href="http://bit.ly/virtualfriam" target="_blank" class="">bit.ly/virtualfriam</a><br class="">unsubscribe <a href="http://redfish.com/mailman/listinfo/friam_redfish.com" target="_blank" class="">http://redfish.com/mailman/listinfo/friam_redfish.com</a><br class="">archives: <a href="http://friam.471366.n2.nabble.com/" target="_blank" class="">http://friam.471366.n2.nabble.com/</a><br class="">FRIAM-COMIC <a href="http://friam-comic.blogspot.com/" target="_blank" class="">http://friam-comic.blogspot.com/</a> <o:p class=""></o:p></div></blockquote></div></div></div>.-. .- -. -.. --- -- -..-. -.. --- - ... -..-. .- -. -.. -..-. -.. .- ... .... . ...<br class="">FRIAM Applied Complexity Group listserv<br class="">Zoom Fridays 9:30a-12p Mtn GMT-6 <a href="http://bit.ly/virtualfriam" class="">bit.ly/virtualfriam</a><br class="">unsubscribe <a href="http://redfish.com/mailman/listinfo/friam_redfish.com" class="">http://redfish.com/mailman/listinfo/friam_redfish.com</a><br class="">archives: <a href="http://friam.471366.n2.nabble.com/" class="">http://friam.471366.n2.nabble.com/</a><br class="">FRIAM-COMIC <a href="http://friam-comic.blogspot.com/" class="">http://friam-comic.blogspot.com/</a> <br class=""></div></blockquote></div><br class=""></div></body></html>