Charge that is positive Positive charge accumulates on the ground underneath the cloud, drawn by the negative charge at the cloud's base. The positive charge of the earth accumulates around everything that stands up-trees, lightning conductors, and even humans! This is because all objects have a small amount of negative charge embedded in their structure. The closer an object is to the ground, the more negative charge it has, so most objects when standing alone don't cause problems for clouds or raindrops.
When this positive charge reaches the cloud, some of it jumps from the object it's attached to (usually a tree) to another object with a negative charge (usually another tree). The charge-carrier trees are now equal in strength and they fall over in love. This is called "discharge" and it happens very quickly, usually within seconds. Fall colors in nature are caused by discharge events happening frequently enough to lighten different parts of the tree differently.
The remaining charge stays with the tree and travels through the branchs and leaves until it reaches the ground. When it does, it causes new growth to be positive like its parent. This is how trees always grow upward toward the light.
Discharges also happen when water drops hit the ground, but they don't affect the landscape visually unless you have a lot of them.
Negative charges accumulate at the cloud's base, whereas positive charges accumulate at the cloud's apex. This causes electric fields to build and expand between the cloud and the ground, as well as within the cloud itself—all of which are required for lightning to strike.
The strength of these electric fields increases with altitude because there are more negative charges available to distribute among Earth's surface area from higher clouds. High-level clouds contain fewer molecules per cubic meter than low-level clouds, so they offer up their electrons more freely. The maximum charge on a cloud may be limited by physical factors such as conductivity or by environmental conditions such as wind speed or humidity. Clouds above thunderstorms can have much greater charge concentrations than those below them.
When the charge differences become large enough, an electrical discharge occurs. A fraction of the energy from the solar radiation falling on the cloud is released in the form of electromagnetic waves that travel through space to reach the ground. This is how most clouds emit light: from their surfaces where incident sunlight creates electron-hole pairs that are separated by the electric field within the cloud; from their interiors where thermal energy is radiated into space; and finally, from any lower layers of gas that have condensed out onto grains of dust or other particles.
Lightning is the rapid release of electrical energy due to the separation of charge.
The charges in the clouds have an effect on the charges on the earth. The ground normally has a small negative charge.
Lightning frequently happens between clouds or between clouds. The strong negative charge in the cloud pulls positive charges on the ground as the storm sweeps over it. Positive charges accumulate in the highest things, such as trees, telephone poles, and houses. These accumulated charges can be very dangerous if they reach a high enough voltage.
The lightening conductor is a tree or other tall object that takes the charge from the cloud and passes it on to lower objects. Without these conductors, most buildings would be destroyed by the charge that builds up during a storm. The conductor's job is made easier because there are many more negative particles in the cloud than positive ones. Thus, it tends to discharge itself before any damage is done.
Buildup of charge occurs when two objects with different charges interact. In this case, one object (the tree) has a lot of negative electrons while the other object (the house) has few positive ions. When these objects touch, the electrons from the tree will move into the house and the tree will become positively charged. Once this happens, it no longer has an effect on future storms because its negative charge is used up.
The house was not damaged because the charge moved into it but rather because the contact between the tree and house caused them to spark.
Lightning Water droplets smash with dust particles, ionising radiation, and each other in storm clouds. Electrons are knocked off the particles and collect in the cloud as a result of these collisions. The negative charges that build at the cloud's base cause positive charges to accumulate on the ground. This is why you often find high concentrations of charge carriers in the soil near trees: They attract electrons from the clouds.
The presence of lightning in a cloud means that it can release its load of water as rain or snow. However, not all clouds with lightning have enough force behind their winds to actually discharge into precipitation. Some remain "balloon" clouds until they collapse under their own weight or are blown apart by stronger winds.
Clouds may also discharge if they are very old or sickly looking. A low-pressure area inside the cloud may not be able to drain away quickly enough and so becomes more and more charged. When this charge reaches 1,000 volts or more, it can trigger an arc between two objects with different charges, causing them both to discharge at the same time.
Finally, clouds may discharge if something triggers them to emit electromagnetic radiation. This could be due to changes in temperature or concentration of certain molecules within the cloud that cause electrons to move around more freely or fall out of the cloud entirely.
As positive and negative charges begin to segregate inside the cloud, an electric field forms between the cloud's top and bottom. The electric field is strengthened when these charges are further separated into pools of positive and negative areas. When this happens, there are more high-energy particles (i.e., electrons) near the top of the cloud than near the bottom. This creates a net force that pushes upward on the cloud's top layer.
Here's how one scientist explains it: "Imagine standing next to a lake with both your feet in the water. If you pull your feet out of the water, they will float up." That's what happens to the charge in a cloud as well. As positive and negative charges separate from each other, they become less likely to join together again, so they stay floating apart instead. This means that even if clouds aren't being touched by any other objects, they still would be able to rise up because of the energy that's trapped within them.
You can think of charges as balls with opposite colors stuck to each other. If you were to pull them away from each other, they would fly off into the air. The same thing happens to charges in clouds; they rise up because they want to be free from their neighbors.
Charges also like to remain separate from other objects with which they are not naturally paired.
Furthermore, a little positive charge forms towards the bottom of the thunderstorm cloud. The negative charge in the centre of a thunderstorm cloud charges the earth underneath it, while the positively charged anvil charges the ground beneath it. This is why you can get lightnings near or even inside buildings; because they will find a path back to ground level through the human body.
The charge on the ground increases the closer you are to the storm. The positive charge from the anvil can be as much as 50,000 volts across. The negative charge from the cloud can be equal to 5,500 volts.
People need to understand that when lightning strikes, both electricity and radio waves are released at the same time. So, even though they may hear only one sound, a loud one, they are actually hearing both. Also, since people have different levels of sensitivity to radio waves and sounds, this could explain some cases where someone claims to have heard something when no one else did.