Apr 20, 2006
The Electric Hurricanes of 2005
Another mystery for meteorologists: As a rule, hurricanes display
little if any lightning. But during the record-setting hurricane
season of 2005 three of the most powerful storms—Rita, Katrina, and
Emily—provoked an astonishing abundance of lightning.
Richard Blakeslee of the Global Hydrology and Climate Center (GHCC)
in Huntsville, Alabama, was one of a team of scientists who explored
Hurricane Emily using NASA's ER-2 aircraft, a research version of
the famous U-2 spy plane. Flying high above the storm, they noted frequent
lightning
in the cylindrical wall of clouds surrounding the hurricane's eye. Both
cloud-to-cloud and cloud-to-ground lightning were present, "a few
flashes per minute", says Blakeslee. "Generally there's not a lot of
lightning in the eye-wall region", Blakeslee says.
In fact, the electric fields above Emily
were among the strongest ever measured by the aircraft’s sensors
over any storm. "We observed steady fields in excess of 8 kilovolts
per meter. That is huge--comparable to the strongest fields we would
expect to find over a large land-based 'mesoscale' thunderstorm”.
According to Blakeslee, the reason for the usual absence of
lightning in hurricanes is understood. “They’re missing vertical
winds” … “A hurricane's winds are mostly
horizontal, not vertical. So the vertical churning that leads to
lightning doesn't normally happen”.
But why did lightning occur in the recent hurricanes? “We still have
a lot to learn about hurricanes”, Blakeslee observes.
Indeed. And we still have a lot to learn about lightning too.
The distinguished expert on lightning, Dr. Martin Uman, has admitted
that the separation of charges in a thunderstorm remains a mystery.
So in truth, the absence of lightning in tornadoes and hurricanes is
not understood.
But the answer becomes both simple and undeniable once the electrical
nature of the solar system is admitted. An electric solar system
could hardly exclude an
electric Earth.
And once we see electrical phenomena on Earth in relation to the
larger circuitry, our planet's atmosphere can be compared to the
leaky dielectric in a “self-repairing
capacitor”:
the charge is already waiting in the ionosphere to be unleashed in
storms in the atmosphere. We have seen the electrical connection of
thunderstorms to the ionosphere in the appearance of
giant
lightning bursts to space. These electrical displays have been named
“red sprites” and “blue
jets”.
From an electrical viewpoint, the vertical winds are not the cause of
charge separation because charge separation already exists; the
winds are driven by electrical discharge activity. But in a
tornado or hurricane the discharge takes on a familiar circular
motion, whereupon powerful electromagnetic forces constrain the
discharge to what has been called a "charge
sheath vortex." Here,
the energy of the discharge goes into driving the vortex, imparting
to it a devastating power, though visible arcing (lightning) may be
minimal.
But it seems that in the most powerful manifestations of the charge sheath
vortex, charge separation in the wall of the vortex itself can
manifest lightning. And if so, meteorologists would be well advised
to expand their investigations of lightning, hurricanes, and
tornadoes into the realm of plasma physics.