Sprites,%20Blue%20Jets,%20and%20Elves

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Sprites, Blue Jets, and Elves

• Whats On the Other Side of the Storm

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What Are They?

• Sprites, Blue Jets and Elves are
  upper-atmospheric lightning recently discovered
  in 1995.
• They are formed when the electric field of
  thunderstorms generates ambient electrons,
  causing them to impact one another and create
  optical emissions only visible from 100s of miles
  away.

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Where They Form
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Sprites

• These form at 70km altitude and move both
  upward and downward from their origination point.
  
• Sprites usually occur during the dying stages of
  a thunderstorm, and are frequent with large
  cloud-to-ground lightning strikes.
• Although Sprites have a weak electromagnetic
  emission, they can reach up to 100km tall,
  sometimes breaking the ozone barrier.

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Blue Jets

• Blue Jets do not occur because of cloud-to-ground
  lightning, but interestingly are frequent during
  hail storms.
• They reach 35km altitude with an upward velocity
  of 112km/s (Geophysical Institute, Heavener,
  Moudry, Sentman and Wescott).
• It is argued that because of its intense
  velocity, blue jets emanate from the center of
  thunderstorms, but this claim is widely disputed
  (Science and Technology News).

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Larger View of Blue Jet
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Elves

• E.l.v.e.s stands for Emissions of Light and VLF
  perturbations due to EMP Sources (Fukunishi et
  al., 1995).
• These generally occur above thunderstorms, both
  in conjunction with sprites and alone.
• At an altitude of 75-95km, they are located
  higher than sprites, and can span horizontally as
  much as 530km (Heavener, Matthew 2000)

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Whats the Big Deal?

• I had two main questions
• How much electromagnetic energy do these forms of
  lightning put out?
• Does the electromagnetic energy have any effect
  on the ozone layer, and if so, what does that
  mean for global warming?

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Sprite, Blue Jet and Elves Electromagnetic
Emissions

• On the whole,red spectral observations (sprites)
  showed an emission of 550-850 nm.
• Blue Jets were stronger, emitting anywhere from
  700-1000 nm, showing a higher energy process was
  at stake.
• (Heavener, Matthew 2000)

• Circular Elves are so short lived that they are
  deemed less important energetically that sprites
  and jets (aww).

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So, What About Global Warming and the Ozone?
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Whaa, wha, whaaaaaa!

• Actually, the technical explanation gets into
  some atmospheric chemistry models, none of which
  I am familiar with
• But, I can say that the amount of electromagnetic
  energy put out by these 3 millisecond bursts are
  not enough to battle the sun once it comes up.
• However, since this is a new field of study for
  chemists and meteorologists alike, these tiny
  changes in the climate systems initial
  conditions might add up to a problem in the long
  run, especially if global warming increases the
  incidences of strong electrical storms, thus
  create more sprites, blue jets, and elves.

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My Conclusion

• They ROCK!

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Sources

• Amato, Ivan. Sprites Trigger Sky-High
  Chemistry.Chemical and Engineering News. 20
  Mar, 2006. Vol 84.
• Barrington-Leigh, C.P., Bell, T.F.,Cummer, S.A.,
  Inan, U.S. Elf Radiation Produced by
  Electrical Currents in Sprites.Space,
  Telecommunications and Radioscience Laboratory,
  Stanford University. Stanford, CA. Geophysical
  Research Letters,15 Apr 1998. Vol 25, No. 8
• Heavener, Matthew J., Moudry, Dana R., Sentman,
  Davis D., Wescott, Eugene M. Sprites, Blue
  Jets, and Elves Optical Evidence of Energy
  Transport Across the Stratopause. Geophysical
  Institute, University of Alaska Fairbanks. 19
  Sept, 1999. Vol 5.