What EXACTLY is lightning?

Question

I know it's electrical, that it is created when clouds collide etc, but what (in scientific terms) is it? How does is occur?
All answers appreciated! :)

Answer 1

Lightning in a thunderstorm occurs because the freezing process that takes place at upper levels of the storm separates positive and negative charges. The action of rising and descending air in the updrafts and downdrafts of the storm separates these charged particles further, and allows broad areas of negative and positive charge to develop within a thunderstorm. Lightning results from the build-up and discharge of electrical energy between positively and negatively charged areas of the storm, and between charged portions of the storm and the ground.

Answer 2

What lighting IS - what you see - is plasma - a partially or totally ionised gas. It is air which has become ionized - some of the electrons in the gas molecules have been detached leaving ions behind. These free electrons allow it to conduct electricity. The current which flows - between clouds or to earth - then rapidly heats the plasma causing it to emit light - lots of it - and also freeing up more electrons. When the charge on the clouds has been dissipated, the current stops, the plasma cools rapidly, the electrons are soaked up by the ions and the plasma reverts to normal air.

What causes the initial ionization event ? A sufficiently high voltage can cause ionisation to occur spontaneously - the gas is said to "break down". Alternatively, something like a high energy cosmic ray particle can cause an ionisation event - a free electron is produced. The voltage generated by the charge on the cloud accelerates this electron so that it get enough energy to ionise other molecules and a chain reaction builds up. This chain reaction manifests as "leaders" - forked lines of relatively faint plasma through the atmosphere carrying little current because they have not yet reached earh (or another cloud) and made a circuit. Once a leader reaches the ground, a large current can flow and the lightning flash occurs.

All this, of course, happens extremely rapidly. The rapid heating and cooling of the air causes a supersonic shock wave - thunder.

Answer 3

Lightning is produced when ice particles in a cloud rub past each other causing them to become either positively or negatively charged (with electricity). The charges build up until there is an excess and there has to be a discharge (the lightning). If the lightning goes from the bottom of the cloud (- charged) to the top of the cloud (+ charged) we get 'sheet' lightning. If it goes to the ground (+ charged) we get 'forked' lightning. Hope this helps

Answer 4

A lightning is a large scale example of an electric spark.A spark or discharge occurs when the electrical potential difference between two points separated by air reaches a high value which is called breakdown potential.This value depends on the conductivity of the air and the distance between the points.So, lightning occurs when the electrical potential difference between the cloud and the ground,or between two clouds,or between parts of cloud exceeds the breakdown potential .Electrical potential differences develop in clouds when positive and negative electrical charges which are produced in clouds are separated from one another.

Answer 5

Lightning
From Wikipedia, the free encyclopedia


Lightning is an atmospheric discharge of electricity, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. A bolt of lightning can travel at a speed of 220,000 km/h (136,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse soil or sand into glass channels. There are over 16 million lightning storms every year.

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.

How lightning initially forms is still a matter of debate: Scientists have studied root causes ranging from atmospheric perturbations (wind, humidity, and atmospheric pressure) to the impact of solar wind and accumulation of charged solar particles. Ice inside a cloud is thought to be a key element in lightning development, and may cause a forcible separation of positive and negative charges within the cloud, thus assisting in the formation of lightning.

Answer 6

Electricity.

Answer 7

Discharge from cloud to cloud (sheet lightning)

or cloud to earth ( fork lightning)

Answer 8

positive and negative charged electrons get created when clouds "rub" together, the friction generates static (positive) and the flash, you see is this phenomenal ammount of energy being discharged to ground (negative)

Answer 9

It's static electricity earthing

Answer 10

me on my push bike