In cumulonimbusice crytals
and water droplets are jostled by the intense vertical air.
These elements collide and cause a separation of charge. Smaller
particles are positively charged, back up to the top of the
cloud while the heavier nuclei and the negative charges down.
The soil is then negatively charged by the water droplets
and ice balls. The cloud is gradually charged with energy.
When the accumulation of energy becomes too large and
especially when there is direct opposition between these charges
then produces an electrical discharge, the lightning.
The main discharge from
the cloud to the ground or another cloud creates an ionized
channel (under the effect of electric charges, the air mass
becomes slightly conductive) invisible called stepped leader.
It branches before touching the ground or another cloud after
1/100 second while moving to about 0,12 miles per second (200
Then by successive leaps,
lightning pilot, kind of filled core of electrons, goes to
ground or the other cloud of positive charge by browsing the
most intensive charge. At the end of last decametres of path,
a discharge from a point of the cloud or the ground (other
similar core) positive charge goes to meet it. When the link
between the two nuclei takes place, the main discharge occurs
(visible), a current from the ground or to the positive source
to the cloud with negative charges.
This positive charge spreads extremely quickly. The heat,
is 5 times the temperature of the Sun and up to 100 million
volts, excites air molecules that emit light by releasing
this energy surplus. There
can be several return discharges into a ligtning, an average
of 3 or 4 with 40 and 80 milliseconds between each discharge.
Lightning strokes can bridge distances of 0,06 to at least
12,42 miles (100 m to at least 20 km) in the case of the sinuous
lightning with a thickness of only 1-2 inches (3 cm) approximately.
They can spread at a speed of 24.854,85
miles pers second (40.000 km/s).
Lightning can also be caused by the friction
of the particles found in the ash cloud during volcanic eruptions.
They can also be created during heavy snow fall for the same
reason but this is quite rare.
As can be seen all the lightnings haven't the same appearance.
There are 3 types of lightnings depending on their shape.
or branched lightning :
It is divided
it is bent
Sinuous lightning :
It has many features and conspicuous segmentsts
But it is said that there is a lightning-shaped ball rare
and little known :
Ball lightning is a luminous sphere of a diameter of about
20 to 40 cm which appears during thunderstorms and which disappears,
or quietly or violently. Witness have even said it would enter
in houses or airplanes for a few seconds. Ball lightning is
a color ranging from yellow to orange from green to blue see
and temperature could reach 17.565,93°F
(9.726,85°C) from the reports
of burns caused by ball lightning. According to research ball
lightning is a highly ionized plasma. Smirnov has been hypothesized
that the fireball could contain sodium-rich particles and
or potassium which would be heated by the chemical reaction,
would emit photons corresponding to certain transitions. So
that would explain why it has been observed balls of various
colors : they correspond to chemical compositions and different
la single photograph in the world of ball lightning
taken in Japan, Nagano, the 07/25/1987 by a student
We can also distinguish lightning depending on where they
are occured :
Intra-cloud lightning (IC) : electric
shock occurs within the same cloud where there are opposite
charges. They represent 75% of the lightning during a thunderstorm
The spider : a browsing discharge below
the anvil thunderstorms, much branched and star or spider
shaped (hence the name) with branches start from a single
point by flash ;
Inter-cloud lightning (CC) : he discharge
of which the channel is visible occurs between two clouds
which can be distant several tens of kilometres between
Lightning between a cloud and the ground
(CG) : but this represents only 10% of the thundery activity
and only 25% of lightning strike the ground :
- Negative lightning fractured and ramified ;
- Positive lightning less fractured, rather sinuous
- Superbolt : a lightning whose intensity is much higher
than the usual values and which is often positive. The flash
is very dazzling with a violent blast of sound ;
- Ascending lightning between the ground and cloud : a lightning
strike from soil and goes back to the cloud with branches
pointing upwards ;
can inform us of the composition of the ambient air of the
lightning will tell us the rain in the air ;
lightning the presence of hail ;
lightning is a sign of a significant amount of dust
in the atmosphere ;
lightning means that the air is very dry.
Régnier helped me correct mistakes, please you
to visit her
Im not english speaker, some improprieties can
appear to english masters.
Could you help me reporting by mail any fault you read.
Thank you for all.