All pages on this website are written by myself, (C) Peter Thomson. I am a real person, not AI.
The Structure of the Tornado
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The Structure of the Tornado
The Structure of the TornadoThe Structure of the Tornado
The Structure of the Tornado
©Peter Thomson 1999/2004
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.
The important points I want you to observe from watching real tornadoes are the following:
- There is a distinct difference in character between the central vortex tube and the outer turbulence vortex.
- The inner tube has smooth edges and spins with little verticalflow.
- The outer vortex rises rapidly from the ground at the base of the inner vortex.
- Condensing vapour appears as the outer vortex rises
- The outer vortex initially rises faster than it spins.
- Debris is thrown violently upwards and outwards.
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.
Many of these are available on the Internet.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
- Note the rising airflow round the tornado.
- Outer turbulence vortex shows visibility due to condensation of water vapour through expansion rather than dust. You can see this condensation forming as it rises. It is not dust sucked up from the ground.
- An inward tangential air inflow is lifting surface dust.
- Notice that this air inflow rises before reaching the core of the vortex. It does not form part of the core.
http://www.uni-stuttgart.de/Wetter/specials/movies/tornado2.mpg Or from cache
- Note again the rising airflow round the tornado.
- From time 00.03 to 00.06 note the small tubular charged sheath vortex is visible inside the larger turbulence vortex .
- Note the difference in appearance betwen the smooth sided core tube and the ragged edged outer tube.
- Even the large tornado in the final sequence is gently rising.
From http://www.kwtv.com/wx/wxcenter.htm is tornado1.mov(857K) Or from cache
This is particularly
- 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.
- 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!
- Shows a charged vortex sheath decaying from the ground upwards.