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Researchers Unravel Mystery of Lightning Diversity

Posted by ScuttleMonkey on from the shocking-research dept.

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."

5 of 65 comments (clear)

  1. Ball Lightening by eldavojohn · · Score: 4, Interesting

    I'm shocked there's no mention here of ball lightening and I wonder if they can time the discharge of 60 MHz RF radiation from each lightening strike. If they can, I would be interested in seeing the outliers that last longer than a fraction of a second. Ball lightening is often reported to last several seconds and I think this would be easy to spot if they wanted to try to verify that it actually occurs in nature.

    --
    My work here is dung.
  2. I got hit by lightning in 1998 by Anonymous Coward · · Score: 4, Interesting

    It hurt.

  3. Power Source? by JohnSearle · · Score: 4, Interesting

    I'm curious as to when they're going to be able to harness this energy as an alternative power source. It would be very cool to see blimps as power stations siphoning off energy from the clouds. I assume this isn't feasible (yet at least), considering I haven't heard anything about it...

    Can any explain the major defects this type of energy gathering?

    - John

    1. Re:Power Source? by JohnSearle · · Score: 2, Interesting

      I didn't specify that it be a necessity that it depend on blimps, it could very well be ground based... According to Wikipedia the CN Tower gets struck 40-50 times per year by lightening. I would figure it would be possible to greatly increase that number if you tried.

      I'm sure you understood the point of my question, which was: why hasn't the clouds been harnessed as a source of energy? No need for belittlement.

      - John

  4. Re:Charging Mechanism? by Mathinker · · Score: 2, Interesting

    > Water molecules evaporating from the trees, vegetation, lakes and oceans carry an ionic charge up to the clouds with them.

    What kind of ionic charge (positive or negative)? What is the mechanism involved?

    > Turbulence within the clouds also help charge build up.

    How?

    Your turbulence explanation sounds like the "when clouds collide they rub against each other and generate massive static electricity" explanation-for-children I remember from (old) books of my tender youth.

    How clouds accumulate the charge separation necessary for lightning is not well understood, as far as I know. There is still a lot of research trying to pin this down. I remember seeing an article which claimed that when a water droplet freezes it causes a charge imbalance to be generated along some axis of the ice crystal, and this in addition to a lot of hypothesizing as to how the charges could get separated was proposed as one mechanism which might enable clouds to accumulate the charges necessary for lightning.