Cause of Lightning: What is the Real Explanation?

[Utter Novice]

First apologies for asking what is in all probability a misconceived question, but here goes.

The accounts of the cause of lightning seems to explain it in terms of turbulence in high clouds causing ice particles to become electrically charged by bumping into each other.

But this seems incorrect to me; there can surely be no charge created by substances of the same type colliding with one another.

Have I missed the point? If so (or indeed if not), how are charges in clouds created?

 

[schip666!]

I think the usual explanation is that molecules "rub against" one another and electrons are pulled off. This is the same as running a comb through your hair or shuffling your feet on a carpet. The electrons "stick" to one of the objects and accumulate until you touch a doorknob or your friend.

 

[Utter Novice]

Thanks schip666. But my confusion is still in place. My understanding was that a charge can only be created if a substance rubs against another substance with a different triboelectric characteristic, hence there is a net transfer of electrons. But if particles of ice collide in the turbulence of a cloud, there can be no such net transfer because (definitionally) ice has the same triboelectric characteristics as itself.

I am sure I have something wrong here, but I don't know what!

 

[ZapperZ]

You might want to read this article:

http://physicsworld.com/cws/article/news/39381

Zz.

 

[sardar]

Thank you for your question. I can assure you that your question is not misconceived. In fact, it is a very valid and important question when it comes to understanding the cause of lightning.

The explanation you mentioned, of turbulence in high clouds causing ice particles to become electrically charged, is just one aspect of the overall process. While it is true that particles of the same type colliding with each other cannot create a charge, lightning is actually a result of a complex series of events that involve different types of particles and interactions.

Firstly, it is important to understand that the Earth's atmosphere is not a homogenous mixture of gases. It contains different layers with varying temperatures, densities, and compositions. These differences create an electrically charged atmosphere, with the upper layers being positively charged and the lower layers being negatively charged.

When water droplets and ice particles form in clouds, they carry a small electric charge. As these particles collide and move within the cloud, the charge gets separated, with the positively charged particles moving towards the top of the cloud and the negatively charged particles moving towards the bottom.

At the same time, the Earth's surface also carries a negative charge. This creates an electrical potential difference between the cloud and the ground, with the cloud being positively charged and the ground being negatively charged.

When the difference in electrical potential becomes too great, it creates a discharge of electricity in the form of lightning. This discharge can occur within the cloud itself, between two clouds, or between the cloud and the ground.

In summary, the cause of lightning is a result of the separation of charges within a cloud and the difference in electrical potential between the cloud and the ground. The process of turbulence and collisions within the cloud is just one part of the overall mechanism. I hope this helps to clarify any misconceptions and provides a better understanding of the real explanation behind lightning.