Naked Science Forum
On the Lighter Side => New Theories => Topic started by: mad aetherist on 17/12/2018 02:19:06
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Hello! First, are tornados and whirlwinds the same? Also, how are they created? What is the frequency per year in an area or around the globe? Thanks!
The creation of tornadoes is not well described on www. What u will find-read is mostly krapp. The natural tendency for a body of air to spin & spiral as it rises is virtually ignored & aint well known (there is some good stuff on swirl-ratio, little else). Primarily air enjoys solar heating when at-near ground level making it less dense, & it rises. Likewise wind at ground level evaporates water from grass etc making the air less dense, & it rises. At a tornado u have both.
Air flows in to replace the rising air. On a breezy day the upflow moves along, & the inflow tends to chase the upflow & tends to curve around the back of the receding upflow. The anticlockwise inflow might overpower the clockwise inflow, in which case the whirlwind or tornado will be ACW. The upflow itself will usually tend to include a CW or ACW movement, & this will usually end up colluding with the CW or ACW inflow. When the CW or ACW motion of the updraft becomes strong then it will create a partial vacuum at center, & the air will become less dense, adding to the updraft. When the CW or ACW motion becomes very powerfull the humid air will fog, & fogging will decrease the bulk volume of the air in the funnel, causing the funnel to tighten & spin faster & draw more air in & up. Fogging also increases the temperature of the air, hencely less density, hencely more updraft (i think that we are up to six causes now). As the wind gets more violent it might pick up some dirt & dust which becomes a seed for more fogging. The presence of the ground allows a very strong vacuum to be established near ground level, assisting the whole process. Low level air is sucked in from a very large radius, all of it relatively warm from solar heating. Now we come to the tornado's main trick. The strongly spinning main core of the updraft causes the adjacent outer layers of air to be accelerated due to friction-viscosity. This spin-up acts well out. The spun-up outer layers of inflow hencely have a stronger spin which manifests as a stronger spin in the main core, which by friction & viscous drag spins-up the outer layers even moreso, which etc etc etc, & u have a tornado.
However most tornadoes are said to start high up below a cloud & are said to expand downwards & then touchdown. I think that this is mostly overstated.
The explanation that really stinks is the one where they say that there is horizontal rotation which ends up turning to the vertical. What a load of krapp.
And the krapp explanation about low level cold continental air from xys meeting warm gulf air from pqr etc etc.
And the krapp explanation re jetstreams etc.
But i have never seen a tornado.
20dec2018: So basically a tornado is kind of heat engine running on a kind of partial steam cycle -- the evaporation & fogging cycle makes it different & more powerful to-than a (dry) dust devil.
Firenadoes surprisingly also involve that-there partial steam cycle, despite the flames.
The fogging cycle in larger tornadoes sets up a violent reverberation-pulsation process that also contributes to noise.
Large tornadoes usually include say 3 or more small funnels so close together that they cant be seen (& possibly many very small funnels). I aint sure whether the 3 rotate CW or ACW together. The very small funnels probly spin the opposite way to the 3.
Tornadoes never by-pass a good trailer park.