Lightning Strikes From The Ground Upwards
This type of lightning can be triggered by a preceding lightning flash or it may initiate entirely on its own.
Lightning strikes from the ground upwards. From discovery channel s amazing raging planet series. The electric field change caused by the preceding flash causes an upward positive leader to initiate from a tall object such as a building tower or wind turbine. First the base of a cloud sends down a little electric discharge called a stepped leader. Upward lightning or ground to cloud lightning is a lightning flash which originates from the top of a grounded object and propagates upward from this point.
A less common type of strike called ground to cloud lightning is upward propagating lightning initiated from a tall grounded object and reaching into the clouds. When these two streamers or ion groups meet visible lightning is created. A typical cloud to ground lightning bolt begins when a step like series of negative charges called a stepped leader races downward from the bottom of a storm cloud toward the earth along a. Negative charges from a thunderstorm slowly lower to the ground while positive charges rise from the ground or an object toward the sky.
A lightning bolt is created from the ground up and also down from the sky. About 25 of all lightning events worldwide are strikes between the atmosphere and earth bound objects. The most important finding about upward lightning is that it primarily occurs when there is a nearby positive cloud to ground flash. A lightning strike or lightning bolt is an electric discharge between the atmosphere and the ground.
For a negative cloud to ground discharge the most common type of lightning striking the ground the stepped leader the channel of ionized air begins in the lower section of a thunderstorm cloud and propagates downward. They mostly originate in a cumulonimbus cloud and terminate on the ground called cloud to ground lightning. Positive lightening travels in reverse by going from the ground up into clouds. This phenomenon occurs because of a difference in charge between a storm cloud and the ground.
The two opposide moving leaders meet in midair usually at a point about 300 feet or less above ground. It descends to the ground in steps each about 50 yards about 46 meters in length. When the tip of the stepped leader approaches the ground one or more upward moving leaders initiate from the ground. Taller objects are more likely than shorter objects to produce the upward channel.