Due to electrostatic induction, the buildings and trees under
the clouds, it often has the opposite charge. As the charge
accumulates, the voltage of thunderclouds will gradually increase.
When the thunderclouds with the different charge and the earth’s
protuberances approach each other to a certain extent, especially
when the electric field between them exceeds 25 - 30 KV/cm,
intense discharge will occur with a strong flash of light.
As the temperature reaches 2,000 degrees at the time of discharge,
the air expands rapidly by heat, and consequently the explosion
roar occurs. This is lightning and thunder.
The size and amount of lightning, as well as its activity,
are related to the topography, meteorological conditions and
latitude of each region. In general, there are more lightning
in the mountains than in the plains, and the more buildings
there are, the more chances to be struck by lightning.
When Does Lightning Hit
Just when you are reading this article, there are probably
1,800 thunderbolts happening all over the world.
They release 600 times of lightening every second, while 100 of them
hit the earth. Lightening can turn a portion of nitrogen in the air
into nitrogenous compounds, which are washed down by the rain.
Each year, every hectare of land on the earth get blessed
by the free fertilizer from the upper air.
Canberra, the capital of Uganda, and Java Island in Indonesia are places
that are most easily hit by lightening. According to the statics,
lightening strikes had once visited Java Island 300 days in a year.
Moreover, the most violent lightening is the one that hit a cottage
near a village in Zimbabwe in 1975, killing 21 people at that time.