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Researchers Unravel Mystery of Lightning Diversity
coondoggie writes to tell us that researchers from Penn State and New Mexico Tech have unraveled the mystery of lightning diversity. A new "Lightning Mapping Array" has been able to show detailed models on how lightning acts. "About 90% of lightning occurs inside clouds and is not visible to the casual observer, researchers said. The researchers wondered if lightning that appears within clouds and the lightning that escapes upward or downward shared the same development mechanisms, researchers said. Lightning forms in clouds when different areas of the cloud become either positively or negatively charged. Once the electric field near a charged area exceeds a certain propagation level, lightning occurs. The type of lightning depends on where the charge builds and where the imbalance in charge exists in the clouds. The mechanism behind different types of lightning is what the new model shows, researchers said."
Water molecules evaporating from the trees, vegetation, lakes and oceans carry an ionic charge up to the clouds with them. Turbulence within the clouds also help charge build up.
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Presumably because noone knows wtf ball lightning even is. The hypothesised explanations include such stuff as it being essentially a ball of burning silica, and a few other things which aren't even, strictly speaking, lightning. As in, an electrical discharge.
So basically we don't _have_ a model for that one at all, and that's a bit mandatory for a simulation.
To make things worse, ball lightning is (compared to regular one) a very rare and unpredictable phenomenon. You can pretty much rely on the next thunderstorm to provide you with a bunch of regular lightning to study. (Fly your kite in it, like Franklin, for example.) Ball lightning is harder to track down and study. You don't know when or where it will happen.
A polar bear is a cartesian bear after a coordinate transform.
It has been reproduced in submarine battery switches on demand, occasionally during shorts in electrical equipment, and of course in Tesla's big coil. He considered it a big nuisance. AFAIK, no one has ever duplicated Tesla's production of Ball Lightning.
There are all sorts of theories. One is that plasma is held in place by the presence of RF radiation somehow induced by lightning. Another theory is that is chemically based upon NO2, so its not electrical at all- other than that the lightning produces the NO2.
None of the theories currently address the eyewitness accounts of the balls going through walls, or just suddenly popping out of nowhere in peoples' houses.
There is an entire book called "Ball Lightning: An Unsolved Problem in Atmospheric Physics" by Mark Stenhoff. Available from Amazon by special order or used copies are available. Its really pricey $160, so I would go for a used copy that is $40 or so.
Physics 101 (skip if this is boring).
Power != energy. Power is the rate of change of energy. Energy is the total needed to do something. This means that if you have a very small amount of energy, but use it fantastically fast, the power is very large. The U of MI laser and a lightning bolt are similar in that the energy is not all that large compared to the power they develop (relative to everyday objects) - due to thier acting over a very short time period. In reality a lignting bolt probably has a few orders of magnitude more energy than a U of MI laser discharge while the laser has an order or two more magnitude more power.
According to wikipedia http://en.wikipedia.org/wiki/Lightning a typical lightning bolt has only 500MJ of energy, or the amount to power a 100 watt bulb for 57.9 days. Given that a Joule can be thought of as a watt second, a typical larger coal plant can produce 1000MW of energy or the same as two average lighting strokes per second. Even smaller power plants weigh in at 10-50MW. It is not feasible to capture lightning even 0.0001% of the time, not to mention storing and converting the power efficently. Therefore it is impractical to even try because there really isn't that much energy to gather.