Right now about 20,000 storms are taking place in the world, throwing about a hundred lightning bolts per second . On average, between 16 and 17 million storms occur each year, about 44,000 a day. This means that 8 million lightning bolts fall a day, capable of releasing energy comparable to 2 million tons of dynamite .
Each lightning bolt is estimated to be about 5 kilometers long by only 1 centimeter wide, and discharges between 1 and 10 billion joules of energy , with a current of up to 200,000 amps and 100 million volts. The surrounding air can reach temperatures of 20,000 ºC , more than three times that of the surface of the Sun, which is around 6,000 ºC. This is why lightning is so deadly.
The process of lightning formation in the atmosphere is complex. It is a colossal electrical discharge that occurs when the upward and downward movement of the air within a cumulonimbus – the storm cloud – creates two zones of opposite electrical potential: positively charged particles accumulate at the top of the cloud and in the lower part, the negatives. When the separation between one and the other is very large, the lightning occurs inside the cloud, between different clouds or between the cloud and the earth. Most of the electrical discharges that are generated in a storm do not reach the earth's surface.
Image: US National Oceanic and Atmospheric Administration
