All about lightning
We should be scared of lightning ?
Lightning is an atmospheric discharge of electricity.One of nature's most awesome phenomena, lightning has fascinated and intrigued man since earliest times.. How lightning initially forms is still a matter of debate. Ice inside a cloud bump into each other as they move around in the air. This thought to be a key element in lightning development.
Each re-strike is separated by a relatively large amount of time, typically 40 to 50 milliseconds. Re-strikes can cause a noticeable "strobe light" effect.
The sound of thunder from a lightning strike is prolonged by successive strokes.
Each successive stroke is preceded by intermediate dart leader strokes akin to, but weaker than, the initial stepped leader. The stroke usually re-uses the discharge channel taken by the previous stroke.
Lightning rapidly heats the air in its immediate vicinity to around 20,000 °C (36,000 °F) - about three times the temperature of the surface of the Sun.
An average bolt of negative lightning carries an electric current of 30 kiloamperes (kA), In the atmospheric electrical discharge, a leader of a bolt of lightning can travel at speeds of 60,000 m/s (220,000 km/h), and can reach temperatures approaching 30,000 °C, hot enough to fuse silica sand into glass channels known as fulgurites which are normally hollow and can extend some distance into the ground.Lightning can also occur within the ash clouds from volcanic eruptions, or can be caused by violent forest fires which generate sufficient dust to create a static charge.
The zigzag shape of the thunderbolt and lightning appears because the rarefied air is a better conductor for the electricity than the compressed air.
In the mountain zones, lightnings can reach a maximum length of 100 m (330 ft) while in the plain they can measure even 30 km (19 mi). The average length of lightning is of 2-3 km (1.2-1.9 mi).
Lightning are important in creating the world's weather. There are three main storm areas on Earth: America, Africa and Australia.Concerning the trees, the thunderbolt and lightning have their preferences, the first place being occupied by the oak. At the opposite pole, the most avoided trees are the birch and the laurel. This predilection is directly connected to the profundity of the roots.
Types of lightning :
