The Structure of the Tornado
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The Structure of the Tornado There are many conventional theories that seek to explain the development of a tornado. Without exception they cannot explain the complex internal structure and energy flows in a simple and logical manner. All the points made can be demonstrated by clips from video of real storms. This shows avery clear difference between the core and surrounding region Good views of the structure as it developes This is a very small tornado that passes over a car - but watch what it does to a tree immediately after. This demonstrates the speed gradient in the core of even a tiny tornado. This video is particularly interesting - look out for the small vortices snaking out horizontally from the main vortex several times. and another with horizontal satellite vortices From http://www.iphc.org/drusa/tornado/vidclip2.html Rotating storm that produced a tornado http://www.uni-stuttgart.de/Wetter/specials/movies/tornado1.mpg Or tornado1.mpg from cache http://www.uni-stuttgart.de/Wetter/specials/movies/tornado2.mpg Or from cache From http://www.kwtv.com/wx/wxcenter.htm is tornado1.mov(857K) Or from cache ... Click this link to see larger image interesting. Not only can we see the charged sheath vortex within the turbulence vortex, but the charged vortex sheath appears to kink and then violently fly apart at 05 to 06. The kink demonstrates that there is no major vertical airflow within the charged sheath vortex. Debris continues to fly up vigorously from the ground, even when the core is not visible This rising airflow rises faster than it rotates. From http://www.kwtv.com/wx/wxcenter.htm is tornado2.mov(389K) Or from cache See the end of sequence A huge tornado, but most of what we can see are hanging plumes of ejected material, in a gently rising and gently rotating air stream. The violence of the charged sheath at the core is not visible. From http://www.kwtv.com/wx/wxcenter.htm is tornado3.mov(933K) Or from cache Another very large tornado with a rising and rotating turbulencevortex. The turbulant nature of the flow is clearly visble in this example. Notice the secondary eddies to the left around 10-11 Notice some heavy debris being thrown up and out Note that even from a huge tornado like this, there is no downflow, or outflow at ground level. From http://redrock.ncsa.uiuc.edu/~jewett/Obs/May1598.html is Overview Or from cache This is a good sequence starting with charged sheath vortex touching down, clearly visible as a thin tube. An ejection cloud starts to build up and an outer turbulence vortex starts to form, but is then blown away - ahead of the vortex - by the surfacewind. The outer turbulence vortex then reforms, and by the time it crosses the road is extremely well defined. At around 16 seconds part of the turbulence vortex is again breaking up in a large curl, again blown out by a wind moving faster than the vortex is travelling http://redrock.ncsa.uiuc.edu/~jewett/Obs/May1598/tornadoSW.mpg Or from cache Is taken from the same original video as above, but shows more detail, up to just before it crosses the road. http://redrock.ncsa.uiuc.edu/~jewett/Obs/May1598/tornadoW.mpg Or from cache Next part of sequence, crossing the road http://redrock.ncsa.uiuc.edu/~jewett/Obs/May1598/tornadoNW.mpg Or from cache Final part of sequence with the outer turbulence vortex losing its upwards momentum. http://www.iphc.org/drusa/tornado/vidclip5.html One of a sequence of the same storm as the rotating storm clip. Notice the outer turbulence vortex is not showing much vertical movement, and no inflow visible at ground level. Notice large debris being ejected up and out and then falling down from the right. http://www.iphc.org/drusa/tornado/vidclip6.html The same storm. Notice the rotation of the cloud base continues as a horizontal rotation without any vertical component . http://www.iphc.org/drusa/tornado/vidclip7.html A good view of the outer turbulence vortex. Notice that the rotation nearest the grounder is faster than the rotation above. http://www.iphc.org/drusa/tornado/vidclip8.html Within the circulation of the turbulence vortex! http://www.stormvideo.com/real/19.rm Shows a charged vortex sheath decaying from the ground upwards.
©Peter Thomson 1999/2004
The important points I want you to observe from watching real tornadoes are the following:
This is particularly