A lightning strike or lightning bolt is an electric discharge between the atmosphere and the ground. Most originate in a cumulonimbus cloud and terminate on the ground, called cloud-to-ground (CG) lightning. A less common type of strike, ground-to-cloud (GC) lightning, is upward-propagating lightning initiated from a tall grounded object and reaching into the clouds. About 69% of all lightning events worldwide are strikes between the atmosphere and earth-bound objects. Most are intracloud (IC) lightning and cloud-to-cloud (CC), where discharges only occur high in the atmosphere.[1][2] Lightning strikes the average commercial aircraft at least once a year, but modern engineering and design means this is rarely a problem. The movement of aircraft through clouds can even cause lightning strikes.[3]
A single lightning event is a "flash", which is a complex, multistage process, some parts of which are not fully understood. Most CG flashes only "strike" one physical location, referred to as a "termination". The primary conducting channel, the bright, coursing light that may be seen and is called a "strike", is only about one inch in diameter, but because of its extreme brilliance, it often looks much larger to the human eye and in photographs. Lightning discharges are typically miles long, but certain types of horizontal discharges can be upwards of tens of miles in length. The entire flash lasts only a fraction of a second.
Chaff and silver iodide crystal concepts were devised to deal directly with the cloud cells, and were dispensed directly into the clouds from an overflying aircraft.
- Fulgurites are a CG lightning discharge event that can produce "petrified lightning", demonstrating the enormous, albeit brief, amount of energy transferred by lightning column. They can visually demonstrate how energy may internally or externally diffuse from one or several central nodes of the termination, and differences between the diameters of these channels, which range from only a few mm to several cm. The possible range of forms and compositions of fulgurites vary dramatically, reflecting the complex electrical, chemical, and physical properties of a target sediment, rock, or biological mass.
- Geomagnetically induced currents are phenomena related to space radiation, causing transients and electrical irregularities that impact electrical and data-transmission systems on a broad scale. Flash EMPs and ground currents operate in the same manner, but they are more frequent and have much more localized effects on technology.
- Keraunopathy is the medical study of lightning casualties and associated treatment.
https://en.wikipedia.org/wiki/Lightning_strike
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