Lightning during a Thunderstorm in Edmonton, Alberta, Canada

Lightning over Oradea in Romania

Lightning over Ryman town. Edmonton (ˈɛdmɨntɨn is the capital of the Canadian province of Alberta. Alberta (ælˈbɝtə is one of Canada's prairie provinces. It became a province on September 1 1905 Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page Oradea (pronunciation in Romanian:, Hungarian: Nagyvárad, colloquially also Várad, German: Großwardein, former Romania ( dated: Rumania, Roumania Northern Poland. Poland (Polska officially the Republic of Poland

Lightning cloud-to-sea over Miramare di Rimini, Italy

Lightning is an atmospheric discharge of electricity, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. Rimini is a city in the Emilia-Romagna region of Italy and capital city of the Province of Rimini. Italy (Italia officially the Italian Republic, (Repubblica Italiana is located on the Italian Peninsula in Southern Europe, and on the two largest Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Plate tectonics and hotspots Divergent plate boundaries At the ^[1] In the atmospheric electrical discharge, a leader of a bolt of lightning can travel at speeds of 60,000 m/s, and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse soil or sand into glass channels. Atmospheric electricity is the regular diurnal variations of the Earth 's atmospheric electromagnetic network (or more broadly any Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 Fulgurites (from the Latin fulgur meaning thunderbolt are natural hollow Carrot -shaped Glass tubes formed in quartzose Sand or soil ^[2][3] There are over 16 million lightning storms every year. ^[1]

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. Plate tectonics and hotspots Divergent plate boundaries At the A wildfire, also known as a wildland fire, forest fire, brush fire, vegetation fire, grass fire, Peat fire, Electric charge is a fundamental conserved property of some Subatomic particles which determines their Electromagnetic interaction. ^[1][4]

How lightning initially forms is still a matter of debate:^[5] 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. Wind is the flow of Air or other Gases that compose an Atmosphere (including but not limited to the Earth's) Humidity is the amount of water vapor in the air In daily language the term "humidity" is normally taken to mean Relative humidity. The solar wind is a Stream of charged particles&mdasha plasma &mdashthat are ejected from the upper atmosphere of the Sun. ^[6] 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. Ice is a Solid phase, usually crystalline, of a Non-metalic substance that is liquid or gas at Room temperature, such as Ammonia In Physics, a charge carrier denotes a free (mobile unbound particle carrying an Electric charge. ^[6]

Historical scientific research

Lightning strikes the Eiffel Tower in 1902. The Eiffel Tower (Tour Eiffel /tuʀ ɛfɛl/ is an Iron Tower built

Benjamin Franklin (1706-1790) endeavored to test the theory that sparks shared some similarity with lightning using a spire which was being erected in Philadelphia. Benjamin Franklin ( April 17 1790 was one of the Founding Fathers of the United States of America. Philadelphia (ˌfɪləˈdɛlfiə While waiting for completion of the spire, he got the idea of instead using a flying object, such as a kite. A kite is a flying tethered object that depends upon the tension of a tethering system During the next thunderstorm, which was in June 1752, it was reported that he raised a kite, accompanied by his son as an assistant. On his end of the string he attached a key, and he tied it to a post with a silk thread. Silk is a natural Protein Fiber, some forms of which can be woven into Textiles The best-known type of silk is obtained from cocoons As time passed, Franklin noticed the loose fibers on the string stretching out; he then brought his hand close to the key and a spark jumped the gap. The rain which had fallen during the storm had soaked the line and made it conductive.

Franklin was not the first to perform the kite experiment. Thomas-François Dalibard and De Lors conducted it at Marly-la-Ville in France a few weeks before Franklin's experiment. Thomas-François Dalibard was born in Crannes-en-Champagne, France in 1709 and died in 1799 This article is about the country For a topic outline on this subject see List of basic France topics. ^[7][8] In his autobiography (written 1771-1788, first published 1790), Franklin clearly states that he performed this experiment after those in France, which occurred weeks before his own experiment, without his prior knowledge as of 1752. ^[9]

As news of the experiment and its particulars spread, people attempted to replicate it. However, experiments involving lightning are always risky and frequently fatal. One of the most well-known deaths during the spate of Franklin imitators was that of Professor George Richmann of Saint Petersburg, Russia. Georg Wilhelm Richmann (Russian Георг Вильгельм Рихман (July 22 1711 ( old style: July 11 1711 &ndash August 6 1753 (old style July 26 1753 Saint Petersburg ( tr: Sankt-Peterburg,) is a city and a federal subject of Russia located on the Neva River Russia (Россия Rossiya) or the Russian Federation ( Rossiyskaya Federatsiya) is a transcontinental Country extending He created a set-up similar to Franklin's, and was attending a meeting of the Academy of Sciences when he heard thunder. Thunder is the sound made by Lightning. Depending on the nature of the lightning and distance of the listener it can range from a sharp He ran home with his engraver to capture the event for posterity. According to reports, while the experiment was under way, ball lightning appeared and collided with Richmann's head, killing him. Ball lightning is an atmospheric electrical phenomenon the physical nature of which is still Controversial. ^[10][11]

Although experiments from the past time of Benjamin Franklin showed that lightning was a discharge of static electricity, there was little improvement in theoretical understanding of lightning (in particular how it was generated) for more than 150 years. Electrostatics is the branch of Science that deals with the Phenomena arising from what seems to be stationary Electric charges Since Classical The impetus for new research came from the field of power engineering: as power transmission lines came into service, engineers needed to know much more about lightning in order to adequately protect lines and equipment. Power engineering, also called power systems engineering, is a subfield of Electrical engineering that deals with the generation, transmission Electric power transmission, a process in the delivery of Electricity to consumers is the bulk transfer of electrical power

Properties of lightning

World map showing frequency of lightning strikes, in flashes per km² per year (equal-area projection). Lightning strikes most frequently in the Democratic Republic of the Congo. The Democratic Republic of the Congo (République démocratique du Congo often referred to as DR Congo, DRC or RDC, and formerly known or referred to Combined 1995–2003 data from the Optical Transient Detector and 1998–2003 data from the Lightning Imaging Sensor.

An average bolt of lightning carries an electric current of 40 kiloamperes (kA) (although some bolts can be up to 120 kA), and transfers a charge of five coulombs and 500 MJ. The ampere, in practice often shortened to amp, (symbol A is a unit of Electric current, or amount of Electric charge per second The coulomb (symbol C) is the SI unit of Electric charge. It is named after Charles-Augustin de Coulomb. The joule (written in lower case ˈdʒuːl or /ˈdʒaʊl/ (symbol J) is the SI unit of Energy measuring heat, Electricity The voltage depends on the length of the bolt, with the dielectric breakdown of air being three million volts per meter; this works out to approximately one gigavolt (one billion volts) for a 300 m (1000 ft) lightning bolt. The term electrical breakdown has several similar but distinctly different meanings The volt (symbol V) is the SI derived unit of electric Potential difference or Electromotive force. The volt (symbol V) is the SI derived unit of electric Potential difference or Electromotive force. With an electric current of 100 kA, this gives a power of 100 terawatts. The watt (symbol W) is the SI derived unit of power, equal to one Joule of energy per Second. However, lightning leader development is not a simple matter of dielectric breakdown, and the ambient electric fields required for lightning leader propagation can be a few orders of magnitude less than dielectric breakdown strength. Further, the potential gradient inside a well-developed return-stroke channel is on the order of hundreds of volts per meter or less due to intense channel ionization, resulting in a true power output on the order of megawatts per meter for a vigorous return-stroke current of 100 kA ^[12].

Lightning heats nearby air to about 10,000 °C (18,000 °F) nearly instantly, which is almost twice the temperature of the Sun’s surface. The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The heating creates a shock wave that is heard as thunder. ^[13]

The return stroke of a lightning bolt follows a charge channel only about a centimeter (0. 4-in) wide — no wider than a pencil. Most lightning bolts are about 1. 6 kilometers (1 mi) long. The longest recorded length was 190 kilometers (118 mi), sighted near Dallas, Texas. ^[14]

Different locations have different potentials (voltages) and currents for an average lightning strike. For example, Florida, with the United States' largest number of recorded strikes in a given period during the summer season, has very sandy ground in some areas and conductive saturated mucky soil in others. As much of Florida lies on a peninsula, it is bordered by the ocean on three sides. The result is the daily development of sea and lake breeze boundaries that collide and produce thunderstorms. Arizona, which has very dry, sandy soil and a very dry air, has cloud bases as high as 1800-2100 m (6,000-7,000 ft) above ground level, and gets very long and thin purplish discharges which crackle; while Oklahoma, with cloud bases about 450-600 m (1,500-2,000 ft) above ground level and fairly soft, clay-rich soil, has big, blue-white explosive lightning strikes that are very hot (high current) and cause sudden, explosive noise when the discharge comes. The difference in each case may consist of differences in voltage levels between clouds and ground. Research on this is still ongoing.

NASA scientists have found the radio waves created by lightning clear a safe zone in the radiation belt surrounding the earth. This zone, known as the Van Allen Belt slot, can potentially be a safe haven for satellites, offering them protection from the Sun's radiation. The Van Allen radiation belt is a Torus of energetic Charged particles ( plasma) around Earth, held in place by Earth's Magnetic ^[15][16][17]

Formation

Note

Positive lightning (a rarer form of lightning that originates from positively charged regions of the thundercloud) does not generally fit the following pattern. Lightning is an atmospheric discharge of Electricity, which typically occurs during Thunderstorms and sometimes during volcanic eruptions or

Charge separation

The first process in the generation of lightning is charge separation.

Polarization mechanism hypothesis

The mechanism by which charge separation happens is still the subject of research, but one hypothesis is the polarization mechanism, which has two components:^[18]

1. Falling droplets of ice and rain become electrically polarized as they fall through the atmosphere's natural electric field;
2. Colliding ice particles become charged by electrostatic induction. Electrostatic induction is a redistribution of Electrical charge in an object caused by the influence of nearby charges

Ice and supercooled water are the keys to the process. Violent winds buffet tiny hailstones as they form, causing them to collide. When the hailstones hit ice crystals, some negative ions transfer from one particle to another. The smaller particles lose negative ions and become positive and the larger more massive particles gain negative ions and become negative. ^[19]

Electrostatic induction hypothesis

Another hypothesis is that opposite charges are driven apart by the above mechanism and energy is stored in the electric field between them. Cloud electrification appears to require strong updrafts which carry water droplets upward, supercooling them to between -10 and -20 °C. These collide with ice crystals to form a soft ice-water mixture called graupel. Graupel (also called snow pellets) refers to precipitation that forms when supercooled Droplets of Water condense on a Snowflake forming The collisions result in a slight positive charge being transferred to ice crystals, and a slight negative charge to the graupel. Updrafts drive lighter ice crystals upwards, causing the cloud top to accumulate increasing positive charge. The heavier negatively charged graupel falls towards the middle and lower portions of the cloud, building up an increasing negative charge. Charge separation and accumulation continue until the electrical potential becomes sufficient to initiate lightning discharges, which occurs when the gathering of positive and negative charges forms a sufficiently strong electric field. At a point in space the electric potential is the Potential energy per unit of charge that is associated with a static (time-invariant Electric field

There are several additional hypotheses for the origin of charge separation. ^[20]

Leader formation

As a thundercloud moves over the Earth's surface, an equal but opposite charge is induced in the Earth below, and the induced ground charge follows the movement of the cloud. Cumulonimbus (Cb is a type of Cloud that is tall dense and involved in Thunderstorms and other intense Weather.

An initial bipolar discharge, or path of ionized air, starts from a negatively charged mixed water and ice region in the thundercloud. Ionization is the physical process of converting an Atom or Molecule into an Ion by adding or removing charged particles such as Electrons Cumulonimbus (Cb is a type of Cloud that is tall dense and involved in Thunderstorms and other intense Weather. The discharge ionized channels are called leaders. The negative charged leaders, called a "stepped leader", proceed generally downward in a number of quick jumps, each up to 50 meters long. A stepped leader (possibly also referred to as a step leader) is a path of ionized air which extends downward from a Thundercloud during the initial stages Along the way, the stepped leader may branch into a number of paths as it continues to descend. The progression of stepped leaders takes a comparatively long time (hundreds of milliseconds) to approach the ground. A millisecond (from Milli- and Second; abbreviation ms is one thousandth of a Second. This initial phase involves a relatively small electric current (tens or hundreds of amperes), and the leader is almost invisible compared to the subsequent lightning channel. Electric current is the flow (movement of Electric charge. The SI unit of electric current is the Ampere. The ampere, in practice often shortened to amp, (symbol A is a unit of Electric current, or amount of Electric charge per second

When a stepped leader approaches the ground, the presence of opposite charges on the ground enhances the electric field. A stepped leader (possibly also referred to as a step leader) is a path of ionized air which extends downward from a Thundercloud during the initial stages The electric field is highest on trees and tall buildings. If the electric field is strong enough, a conductive discharge (called a positive streamer) can develop from these points. A positive streamer is the bit of a Lightning bolt that rises from the ground before the lightning strikes often determining the path of the cloud-to-ground lightning This was first theorized by Heinz Kasemir. As the field increases, the positive streamer may evolve into a hotter, higher current leader which eventually connects to the descending stepped leader from the cloud. It is also possible for many streamers to develop from many different objects simultaneously, with only one connecting with the leader and forming the main discharge path. Photographs have been taken on which non-connected streamers are clearly visible. When the two leaders meet, the electric current greatly increases. The region of high current propagates back up the positive stepped leader into the cloud with a "return stroke" that is the most luminous part of the lightning discharge. In photometry, luminous intensity is a measure of the wavelength-weighted power emitted by a Light source in a particular direction per unit Solid

Discharge

Lightning sequence (Duration: 0. 32 seconds)

When the electric field becomes strong enough, an electrical discharge (the bolt of lightning) occurs within clouds or between clouds and the ground. Electrostatic discharge ( ESD) is the sudden and momentary Electric current that flows between two objects at different Electrical potentials The term is During the strike, successive portions of air become a conductive discharge channel as the electrons and positive ions of air molecules are pulled away from each other and forced to flow in opposite directions.

The electrical discharge rapidly superheats the discharge channel, causing the air to expand rapidly and produce a shock wave heard as thunder. See Superheater for the device used in Steam engines In Physics, superheating (sometimes referred to as boiling retardation For the music album by Converter see Shock Front For the 1977 horror film see Shock Waves A shock wave (also called The rolling and gradually dissipating rumble of thunder is caused by the time delay of sound coming from different portions of a long stroke. ^[21]

Gurevich's runaway breakdown theory

Main article: Runaway breakdown

A theory of lightning initiation, known as the "runaway breakdown theory", proposed by Aleksandr Gurevich of the Lebedev Physical Institute in 1992 suggests that lightning strikes are triggered by cosmic rays which ionize atoms, releasing electrons that are accelerated by the electric fields, ionizing other air molecules and making the air conductive by a runaway breakdown, then "seeding" a lightning strike. Runaway breakdown is a theory of Lightning initiation proposed by Alex Gurevich in 1992. Aleksandr Viktorovich Gurevich (Александр Викторович Гуревич (b The Lebedev Physics Institute of the Russian Academy of Sciences, situated in Moscow, is one of the leading Russian research institutes specializing in Physics For the 1962 Bruce Conner film see Cosmic Ray (film Cosmic rays are energetic particles originating from space that impinge on ^[22][23][24]

Gamma rays and the runaway breakdown theory

Double lightning

It has been discovered in the past 15 years that among the processes of lightning is some mechanism capable of generating gamma rays, which escape the atmosphere and are observed by orbiting spacecraft. Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions Brought to light by NASA's Gerald Fishman in 1994 in an article in Nature, these so-called Terrestrial Gamma-Ray Flashes (TGFs) were observed by accident, while he was documenting instances of extraterrestrial gamma ray bursts observed by the Compton Gamma Ray Observatory (CGRO). The National Aeronautics and Space Administration ( NASA, ˈnæsə is an agency of the United States government, responsible for the nation's public space program Nature is a prominent Scientific journal, first published on 4 November 1869 Terrestrial gamma-ray flashes (TGFs are bursts of Gamma rays in the earth's atmosphere TGFs are much shorter in duration, however, lasting only ~1 ms.

Professor Umran Inan of Stanford University linked a TGF to an individual lightning stroke occurring within 1. Leland Stanford Junior University, commonly known as Stanford University or simply Stanford, is a private Research university located in 5 ms of the TGF event,^[25] proving for the first time that the TGF was of atmospheric origin and associated with lightning strikes.

CGRO recorded only about 77 events in 10 years; however, more recently the RHESSI spacecraft, as reported by David Smith of UC Santa Cruz, has been observing TGFs at a much higher rate, indicating that these occur ~50 times per day globally (still a very small fraction of the total lightning on the planet). Reuven Ramaty High Energy Solar Spectroscopic Imager ( RHESSI, or more rarely Explorer 81) is the sixth mission in the line of NASA Small Explorer The energy levels recorded exceed 20 MeV.

Scientists from Duke University have also been studying the link between certain lightning events and the mysterious gamma ray emissions that emanate from the Earth's own atmosphere, in light of newer observations of TGFs made by RHESSI. Duke University is a private Research University located in Durham, North Carolina, United States. Their study suggests that this gamma radiation fountains upward from starting points at surprisingly low altitudes in thunderclouds.

Steven Cummer, from Duke University's Pratt School of Engineering, said, "These are higher energy gamma rays than come from the sun. And yet here they are coming from the kind of terrestrial thunderstorm that we see here all the time. "

Early hypotheses of this pointed to lightning generating high electric fields at altitudes well above the cloud, where the thin atmosphere allows gamma rays to easily escape into space, known as "relativistic runaway breakdown", similar to the way sprites are generated. Upper-atmospheric lightning is an obsolete term that is no longer used by researchers to refer to a family of electrical breakdown phenomena that occurs well above the altitudes of normal Subsequent evidence has cast doubt, though, and suggested instead that TGFs may be produced at the tops of high thunderclouds. Though hindered by atmospheric absorption of the escaping gamma rays, these theories do not require the exceptionally high electric fields that high altitude theories of TGF generation rely on.

The role of TGFs and their relationship to lightning remains a subject of ongoing scientific study.

Re-strike

Lightning is a highly visible form of energy transfer. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός

High speed videos (examined frame-by frame) show that most lightning strikes are made up of multiple individual strokes. A typical strike is made of 3 to 4 strokes. There may be more. ^[21]

Each re-strike is separated by a relatively large amount of time, typically 40 to 50 milliseconds. Re-strikes can cause a noticeable "strobe light" effect. ^[21]

Each successive stroke is preceded by intermediate dart leader strokes again to, but weaker than, the initial stepped leader. A dart leader (also known as a continuous leader; may have been referred to by Feynman as a dark leader) is the Cloud -to-ground movement of Electrons The stroke usually re-uses the discharge channel taken by the previous stroke. ^[21]

The variations in successive discharges are the result of smaller regions of charge within the cloud being depleted by successive strokes.

The sound of thunder from a lightning strike is prolonged by successive strokes. Thunder is the sound made by Lightning. Depending on the nature of the lightning and distance of the listener it can range from a sharp

Types of lightning

Cloud-to-cloud lightning, Steinenbronn, Germany

Some lightning strikes take on particular characteristics; scientists and the public have given names to these various types of lightning. Steinenbronn is a town in the district of Böblingen in Baden-Württemberg in Germany. Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. Most lightning is streak lightning. This is nothing more than the return stroke, the visible part of the lightning stroke. Because most of these strokes occur inside a cloud, we do not see many of the individual return strokes in a thunderstorm.

The return stroke of a lightning bolt, which is the visible bolt itself, follows a charge channel only about a half-inch (1. 3 cm) wide. Most lightning bolts are about a mile (1. 6 km) long. ^[26]

Positive lightning

See also: High_voltage#Lightning

Positive lightning, also known colloquially as a "bolt from the blue" makes up less than 5% of all lightning. The term high voltage characterizes electrical circuits in which the voltage used is the cause of particular safety concerns and insulation requirements For the athlete referred to by the same name see Usain Bolt A bolt from the blue is a form of Lightning that strikes out of an apparently ^[27] It occurs when the leader forms at the positively charged cloud tops, with the consequence that a negatively charged streamer issues from the ground. The overall effect is a discharge of positive charges to the ground. Research carried out after the discovery of positive lightning in the 1970s showed that positive lightning bolts are typically six to ten times more powerful than negative bolts, last around ten times longer, and can strike tens of kilometres/miles from the clouds. The kilometre ( American spelling: kilometer) symbol km is a unit of Length in the Metric system, equal to one thousand ^[28] The voltage difference for positive lightning must be considerably higher, due to the tens of thousands of additional metres/feet the strike must travel. The metre or meter is a unit of Length. It is the basic unit of Length in the Metric system and in the International During a positive lightning strike, huge quantities of ELF and VLF radio waves are generated. Extremely low frequency (ELF is the band of Radio frequencies from 3 to 30 Hz. Very low frequency or VLF refers to radio frequencies (RF in the range of 3 KHz to 30 KHz. Radio waves are electromagnetic waves occurring on the Radio frequency portion of the Electromagnetic spectrum. ^[29]

As a result of their greater power, positive lightning strikes are considerably more dangerous. At the present time, aircraft are not designed to withstand such strikes, since their existence was unknown at the time standards were set, and the dangers unappreciated until the destruction of a glider in 1999. Terminology A "glider" is an unpowered Aircraft. The most common types of glider are today used for sporting purposes ^[30]

Positive lightning is also now believed to have been responsible for the 1963 in-flight explosion and subsequent crash of Pan Am Flight 214, a Boeing 707. Pan Am Flight 214, a Boeing 707-121 registered as, was a domestic scheduled passenger flight from Baltimore to Philadelphia, which crashed on WikipediaWikiProject Aircraft. Please see WikipediaWikiProject Aircraft/page content for recommended layout Subsequently, aircraft operating in U. S. airspace have been required to have lightning discharge wicks to reduce the chances of a similar occurrence.

Positive lightning has also been shown to trigger the occurrence of upper atmosphere lightning. It tends to occur more frequently in winter storms and at the end of a thunderstorm. A winter storm is an event in which the dominant varieties of precipitation are forms that only occur at cold Temperatures such as Snow or ^[31]

An average bolt of positive lightning carries a current of up to 300 kA (kiloamperes) (about ten times as much current as a bolt of negative lightning), transfers a charge of up to 300 coulombs, has a potential difference up to 1 gigavolt (one billion volts), and lasts for hundreds of milliseconds, with a discharge energy of up to 300 GJ (gigajoules) (a billion joules). The ampere, in practice often shortened to amp, (symbol A is a unit of Electric current, or amount of Electric charge per second The coulomb (symbol C) is the SI unit of Electric charge. It is named after Charles-Augustin de Coulomb. The volt (symbol V) is the SI derived unit of electric Potential difference or Electromotive force. The joule (written in lower case ˈdʒuːl or /ˈdʒaʊl/ (symbol J) is the SI unit of Energy measuring heat, Electricity

Anvil-to-ground

One special type of cloud-to-ground lightning is anvil-to-ground lightning. It is a form of positive lightning, since it emanates from the anvil top of a cumulonimbus cloud where the ice crystals are positively charged. Cumulonimbus (Cb is a type of Cloud that is tall dense and involved in Thunderstorms and other intense Weather. The leader stroke issues forth in a nearly horizontal direction until it veers toward the ground. These usually occur kilometers/miles from (often ahead) of the main storm and will sometimes strike without warning on a sunny day. An anvil-to-ground lightning bolt is a sign of an approaching storm, and if one occurs in a largely clear sky, it is known colloquially as a "Bolt from the blue. For the athlete referred to by the same name see Usain Bolt A bolt from the blue is a form of Lightning that strikes out of an apparently "^[32]

Cloud-to-cloud

Multiple paths of cloud-to-cloud lightning, Swifts Creek, Australia

Lightning discharges may occur between areas of cloud having different potentials without contacting the ground. Swifts Creek is a rural community located between Omeo and Ensay on the Great Alpine Road in East Gippsland, Victoria, Australia For a topic outline on this subject see List of basic Australia topics. These are most common between the anvil and lower reaches of a given thunderstorm. This lightning can sometimes be observed at great distances at night as so-called "heat lightning". In such instances, the observer may see only a flash of light without thunder. The "heat" portion of the term is a folk association between locally-experienced warmth and the distant lightning flashes.

Another terminology used for cloud-cloud or cloud-cloud-ground lightning is "Anvil Crawler", due to the habit of the charge typically originating from beneath or within the anvil and scrambling through the upper cloud layers of a thunderstorm, normally generating multiple branch strokes which are dramatic to witness. These are usually seen as a thunderstorm passes over you or begins to decay. The most vivid crawler behavior occurs in well developed thunderstorms that feature extensive rear anvil shearing.

Dry lightning

Dry lightning is a term in the United States for thunderstorms which produce no precipitation at the surface. Dry lightning is a term which is used to refer to lightning strikes occurring without precipitation This type of lightning is the most common natural cause of wildfires. Dry lightning may also be referred to as heat lightning.

Rocket lightning

It is a form of cloud discharge, generally horizontal and at cloud base, with a luminous channel appearing to advance through the air with visually resolvable speed, often intermittently. In Astronomy, Geography, Geometry and related sciences and contexts a plane is said to be horizontal at a given point if it is locally ^[33]

The movement has been compared to that of a skyrocket, hence its name. A skyrocket is a type of Firework that uses a Solid rocket motor to rise quickly into the sky It is also one of the rarest of cloud discharges. A cloud is a visible mass of droplets or frozen crystals floating in the atmosphere above the surface of the Earth or another Planetary body ^[34]

Cloud-to-ground

Cloud-to-ground lightning is a great lightning discharge between a cumulonimbus cloud and the ground initiated by the downward-moving leader stroke. This is the second most common type of lightning, and poses the greatest threat to life and property of all known types.

Bead lightning

Bead lightning is a type of cloud-to-ground lightning which appears to break up into a string of short, bright sections, which last longer than the usual discharge channel. It is fairly rare. Several theories have been proposed to explain it; one is that the observer sees portions of the lightning channel end on, and that these portions appear especially bright. Another is that, in bead lightning, the width of the lightning channel varies; as the lightning channel cools and fades, the wider sections cool more slowly and remain visible longer, appearing as a string of beads. ^[35][36]

Ribbon lightning

Ribbon lightning occurs in thunderstorms with high cross winds and multiple return strokes. The wind will blow each successive return stroke slightly to one side of the previous return stroke, causing a ribbon effect.

Staccato lightning

Staccato lightning is nothing more than a leader stroke with only one return stroke.

Ground-to-cloud lightning

Ground-to-cloud lightning is a lightning discharge between the ground and a cumulonimbus cloud from an upward-moving leader stroke.

Ball lightning

Main article: Ball lightning

Ball lightning is described as a floating, illuminated ball that occurs during thunderstorms. Ball lightning is an atmospheric electrical phenomenon the physical nature of which is still Controversial. They can be fast moving, slow moving or nearly stationary. Some make hissing or crackling noises or no noise at all. Some have been known to pass through windows and even dissipate with a bang. Ball lightning has been described by eyewitnesses but rarely recorded by meteorologists. Meteorology (from Greek grc μετέωρος metéōros, "high in the sky" and grc -λογία -logia) is the Interdisciplinary ^[37]

The engineer Nikola Tesla wrote, "I have succeeded in determining the mode of their formation and producing them artificially". There have already been discussions about Tesla's ethnicity on the talk page ^[38] There is some speculation that electrical breakdown and arcing of cotton and gutta-percha wire insulation used by Tesla may have been a contributing factor, since some theories of ball lightning require the involvement of carbonaceous materials. The term electrical breakdown has several similar but distinctly different meanings An electric arc is an Electrical breakdown of a gas which produces an ongoing plasma discharge, resulting from a current flowing through normally nonconductive Cotton is a soft staple Fibre that grows around the seeds of the cotton plant ( Gossypium sp Gutta-percha ( Palaquium) is a genus of tropical Trees native to Southeast Asia and northern Australasia, from Taiwan south to Some later experimenters have been able to briefly produce small luminous balls by igniting carbon-containing materials atop sparking Tesla Coils. A Tesla coil is a type of resonant transformer circuit invented by Serbian-American scientist Nikola Tesla around 1891

Several theories have been advanced to describe ball lightning, with none being universally accepted. Any complete theory of ball lightning must be able to describe the wide range of reported properties, such as those described in Singer's book "The Nature of Ball Lightning" and also more contemporary research. Japanese research shows that several instances have been reported of ball lightning without any connection to stormy weather or lightning.

Ball lightning is typically 20 – 30 cm (8-12 inches) in diameter, but ball lightning several meters in diameter has been reported. ^[39] Ball lightning has been seen in tornadoes, and has also been seen to split apart into two or more separate balls and recombine, and vertically-linked fireballs have been reported. A tornado is a violent rotating column of air which is in contact with both the surface of the earth and a Cumulonimbus cloud or in rare cases the base of a Cumulus Ball lightning has carved trenches in the peat swamps in Ireland. Peat is an accumulation of partially Decayed Vegetation matter. A swamp is a Wetland featuring temporary or permanent inundation of large areas of land by shallow bodies of water Ireland (pronounced /ˈaɾlənd/ Éire) is the third largest island in Europe, and the twentieth-largest island in the world Because of its strange behavior, ball lightning has been mistaken for a UFO by many witnesses. One theory that may account for this wider spectrum of observational evidence is the idea of combustion inside the low-velocity region of axisymmetric (spherical) vortex breakdown of a natural vortex (e. Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of V erification of the O rigins of R otation in T ornadoes Ex periment or VORTEX, is a field project that seeks to understand how a g. , the 'Hill's spherical vortex'). A vortex ring, also called a toroidal vortex, is a region of rotating Fluid moving through the same or different fluid where the flow pattern takes on a ^[40]

Ball lightning apparently is created when lightning strikes silicon in soil, and has been created in a lab in this manner. ^[41]

Upper-atmospheric

Main article: Upper-atmospheric lightning

Reports by scientists of strange lightning phenomena above storms date back to at least 1886. Upper-atmospheric lightning is an obsolete term that is no longer used by researchers to refer to a family of electrical breakdown phenomena that occurs well above the altitudes of normal However, it is only in recent years that fuller investigations have been made. This has sometimes been called megalightning. ^[42][43]

Sprites

Sprites are now well-documented electrical discharges that occur high above some types of thunderstorms. They appear as luminous reddish-orange or greenish-blue, plasma-like flashes, last longer than normal lower stratospheric discharges (typically around 17 milliseconds), and are triggered by the discharges of positive lightning between the thundercloud and the ground. In Physics and Chemistry, plasma is an Ionized Gas, in which a certain proportion of Electrons are free rather than being bound ^[29] Sprites often occur in clusters of two or more, and typically span the distance from 50 miles (80 km) to 90 miles (145 km) above the earth, with what appear to be tendrils hanging below, and branches reaching above. A 2007 paper reports that the apparent tendrils and branches of sprites are actually formed by bright streamer heads of less than 140 m diameter moving up or down at 1 to 10 percent of the speed of light. ^[44] The abstract is publicly accessible. ^[45][46][43]

Sprites may be horizontally displaced by up to 30 miles (48 km) from the location of the underlying lightning strike, with a time delay following the lightning that is typically a few milliseconds, but on rare occasions may be up to 100 milliseconds. Sprites are sometimes, but not always, preceded by a sprite halo, a broad, pancake-like region of transient optical emission centered at an altitude of about 47 miles (76 km) above lightning. ^[42] Sprite halos are produced by weak ionization from transient electric fields of the same type that causes sprites, but which are insufficiently intense to exceed the threshold needed for sprites. Sprites were first photographed on July 6, 1989 by scientists from the University of Minnesota. The University of Minnesota Twin Cities ( U of M or The U) is the oldest and largest part of the University of Minnesota system. Several years after their discovery they were named after the mischievous sprite (air spirit) Puck in Shakespeare's Midsummer Night's Dream. William Shakespeare ( baptised A Midsummer Night's Dream is a romantic comedy by William Shakespeare, suggested by " The Knight's Tale " from

Recent research carried out at the University of Houston in 2002 indicates that some normal (negative) lightning discharges produce a sprite halo, the precursor of a sprite, and that every lightning bolt between cloud and ground attempts to produce a sprite or a sprite halo. The University of Houston (often referred to as " U of H," " UH," or " Houston " is a public doctoral/research Research in 2004 by scientists from Tohoku University found that very low frequency emissions occur at the same time as the sprite, indicating that a discharge within the cloud may generate the sprites. abbreviated to, located in the city of Sendai, Miyagi Prefecture in the Tōhoku Region, Japan, is one of Japan's most prestigious national universities Very low frequency or VLF refers to radio frequencies (RF in the range of 3 KHz to 30 KHz. ^[45]

Blue jets

Blue jets differ from sprites in that they project from the top of the cumulonimbus above a thunderstorm, typically in a narrow cone, to the lowest levels of the ionosphere 25 miles (40 km) to 30 miles (48 km) above the earth. The ionosphere is the uppermost part of the atmosphere, distinguished because it is Ionized by solar radiation They are also brighter than sprites and, as implied by their name, are blue in color. They were first recorded on October 21, 1989, on a video taken from the space shuttle as it passed over Australia, and subsequently extensively documented in 1994 during aircraft research flights by the University of Alaska. Events 1512 - Martin Luther joins the theological faculty of the University of Wittenberg. Year 1989 ( MCMLXXXIX) was a Common year starting on Sunday (link displays 1989 Gregorian calendar) NASA 's Space Shuttle, officially called the Space Transportation System ( STS) is the Spacecraft currently used by the United States ^[47][48][43]

On September 14, 2001, scientists at the Arecibo Observatory photographed a huge jet double the height of those previously observed, reaching around 50 miles (80 km) into the atmosphere. Events 81 - Domitian becomes Emperor of the Roman Empire upon the death of his brother Titus. Year 2001 ( MMI) was a Common year starting on Monday according to the Gregorian calendar. The Arecibo Observatory is a very sensitive Radio telescope located approximately south-southwest from the town of Arecibo in Puerto Rico. The jet was located above a thunderstorm over the ocean, and lasted under a second. Lightning was initially observed traveling up at around 50,000 m/s in a similar way to a typical blue jet, but then divided in two and sped at 250,000 m/s to the ionosphere, where they spread out in a bright burst of light. ^[49] On July 22, 2002, five gigantic jets between 60 and 70 km (35 to 45 miles) in length were observed over the South China Sea from Taiwan, reported in Nature. Events 1099 - First Crusade: Godfrey of Bouillon is elected the first Defender of the Holy Sepulchre of The Kingdom of See also 2002 (disambiguation Year 2002 ( MMII) was a Common year starting on Tuesday of the Gregorian calendar. The South China Sea is a Marginal sea south of China. It is a part of the Pacific Ocean, encompassing an area from Singapore to the Taiwan ( Taiwanese: Tâi-oân/Tāi-oân (historically 大灣/台員/大員/台圓/大圓/台窩灣 is an Island in East Asia. ^[47] The jets lasted under a second, with shapes likened by the researchers to giant trees and carrots.

In 2001, the Arecibo scientists modeled the blue-jet phenomenon to better understand how it works. It is like an electron avalanche that can flood up toward the ionosphere or slide earthward, depending on the electric field direction. The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J In Physics, the space surrounding an Electric charge or in the presence of a time-varying Magnetic field has a property called an electric field (that can Intense hail may trigger the avalanche. The field accelerates the electrons and slams them into air molecules. The molecules break down into ions and free electrons and emit light. An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J The newly generated electrons also accelerate. ^[48]

Elves

Elves often appear as dim, flattened, expanding glows around 250 miles (402 km) in diameter that last for, typically, just one millisecond. ^[50] They occur in the ionosphere 60 miles (97 km) above the ground over thunderstorms. Their color was a puzzle for some time, but is now believed to be a red hue. Elves were first recorded on another shuttle mission, this time recorded off French Guiana on October 7, 1990. French Guiana (Guyane française officially fr ''Guyane'' is an Overseas department (French département d'outre-mer, or DOM) of France Events 3761 BC - The epoch (origin of the modern Hebrew calendar ( Proleptic Julian calendar) Year 1990 ( MCMXC) was a Common year starting on Monday (link displays the 1990 Gregorian calendar) Elves is a frivolous acronym for Emissions of Light and Very Low Frequency Perturbations From Electromagnetic Pulse Sources. An elf is a creature of Norse mythology. The elves were originally imagined as a race of minor nature and fertility gods, who are often pictured as youthful-seeming Acronyms, initialisms, and alphabetisms are Abbreviations that are formed using the initial components in a phrase or name This refers to the process by which the light is generated; the excitation of nitrogen molecules due to electron collisions (the electrons possibly having been energized by the electromagnetic pulse caused by a discharge from the Ionosphere). Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J ^[43]

Triggered lightning

Rocket-triggered

Volcanic material thrust high into the atmosphere can trigger lightning.

Lightning has been triggered directly by human activity in several instances. Lightning struck the Apollo 12 soon after takeoff, and has struck soon after thermonuclear explosions. In Physics and Nuclear chemistry, nuclear fusion is the process by which multiple- like charged atomic nuclei join together to form a heavier nucleus ^[51] It has also been triggered by launching lightning rockets carrying spools of wire into thunderstorms. A lightning rocket consists of a Rocket launcher that is in communication with a detection device that measures the presence of Electrostatic and Ionic change The wire unwinds as the rocket ascends, providing a path for lightning. These bolts are typically very straight due to the path created by the wire. ^[52]

Flying aircraft can trigger lightning. ^[53]

Volcanically-triggered

Extremely large volcanic eruptions, which eject gases and material high into the atmosphere, can trigger lightning. This phenomenon was documented by Pliny The Elder during the AD79 eruption of Vesuvius, in which he perished. Gaius or Caius Plinius Secundus, ( AD 23 – August 25, AD 79 better known as Pliny the Elder, was an ancient Author Mount Vesuvius (in Italian Monte Vesuvio and in Latin Mons Vesuvius) is an active Stratovolcano east of Naples ^[54]

Laser-triggered

Since at least the 1970s, researchers have attempted to trigger lightning strikes by means of ultra-violet lasers, which create a channel of ionized gas through which the lightning would be conducted to ground. Such triggered lightning is intended to protect rocket launching pads, electric power facilities, and other sensitive targets. ^{[55][56][57][58][59][60]}

In New Mexico, U. S. , scientists tested a new terawatt laser which provoked lightning. The watt (symbol W) is the SI derived unit of power, equal to one Joule of energy per Second. Scientists fired ultra-fast pulses from an extremely powerful laser thus sending several terawatts into the clouds to call down electrical discharges in storm clouds over the region.

The beams sent from the laser make channels of ionized molecules known as "filaments". Before the lighting strikes earth, the filaments lead electricity through the clouds, playing the role of lightning rods.

Researchers generated filaments that lived too short a period to trigger a real lightning strike. Nevertheless, a boost in electrical activity within the clouds was registered. According to the French and German scientists, who ran the experiment, the fast pulses sent from the laser will be able to provoke lightning strikes on demand. ^[61]

Extraterrestrial lightning

Lightning requires the electrical breakdown of a gas, so it cannot exist in a visual form in the vacuum of space. This vacuum means "absence of matter" or "an empty area or space" for the cleaning appliance see Vacuum cleaner. However, lightning has been observed within the atmospheres of other planets, such as Venus, Jupiter and Saturn. An atmosphere (from Greek ατμός - atmos, " Vapor " + σφαίρα - sphaira, " Sphere " A planet, as defined by the International Astronomical Union (IAU is a celestial body Orbiting a Star or stellar remnant that is The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University Lightning on Venus is still a controversial subject after decades of study. During the Soviet Venera and U. The Venera (Венера series of probes was developed by the USSR between 1961 and 1984 to gather data from Venus. S. Pioneer missions of the 1970s and '80s, signals suggesting lightning may be present in the upper atmosphere were detected. The US Pioneer program of Unmanned space missions was designed for planetary exploration ^[62] However, recently the Cassini-Huygens mission fly-by of Venus detected no signs of lightning at all. Cassini–Huygens is a joint NASA / ESA / ASI Robotic spacecraft mission currently studying the planet Saturn and its Despite this, in 2007, radio pulses recorded by the spacecraft Venus Express confirmed lightning on Venus. (S&T, Mar. 2008)

Trees and lightning

Lightning damage to tree in Maplewood, NJ

Eucalyptus tree that was blown apart by a lightning strike

Trees are frequent conductors of lightning to the ground. Eucalyptus (From Greek ευκάλυπτος meaning "well covered" is a diverse Genus of Trees (and a few shrubs the members of which A tree is a perennial Woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or In Science and engineering, a conductor is a material which contains movable Electric charges. ^[63] Since sap is a poor conductor, its electrical resistance causes it to be heated explosively into steam, which blows off the bark outside the lightning's path. Electrical resistance is a ratio of the degree to which an object opposes an Electric current through it measured in Ohms Its reciprocal quantity is A steam Explosion (also called a Littoral explosion, or fuel-coolant interaction, FCI) is a violent Uses A Steam engine uses the expansion of steam in order to drive a Piston or Turbine to perform Mechanical work. Bark, also known as periderm is the outermost layer of stems and Roots of Woody plants such as Trees It overlays the Wood and consists In following seasons trees overgrow the damaged area and may cover it completely, leaving only a vertical scar. If the damage is severe, the tree may not be able to recover, and decay sets in, eventually killing the tree. Decomposition (or spoilage) refers to the break down of tissue of a formerly living Organism into simpler forms of matter It is commonly thought that a tree standing alone is more frequently struck, though in some forested areas, lightning scars can be seen on almost every tree. A forest is an area with a high density of Trees There are many definitions of a forest based on various criteria

Three eucalyptus trees that were struck by lightning, Walcha, NSW

After the two most frequently struck tree types, the Oak and the Elm,^[64] the Pine tree is also quite often hit by lightning. The term oak can be used as part of the common name of any of about 400 species of Trees and Shrubs in the Genus Quercus (from Latin Elms are Deciduous and Semi-deciduous Trees comprising the genus Ulmus, family Ulmaceae, found This article is about the tree For other uses of the term "pine" see Pine (disambiguation. Unlike the Oak, which has a relatively shallow root structure, pine trees have a deep central root system that goes down into the water table. ROOT is an object-oriented program and library developed by CERN. ^[65] Pine trees usually stand taller than other species, which also makes them a likely target. Factors which lead to its being targeted are a high resin content, loftiness, and its needles which lend themselves to a high electrical discharge during a thunderstorm.

Trees are natural lightning conductors, and are known to provide protection against lightning damages to the nearby buildings. Tall trees with high biomass for the root system provide good lightning protection. An example is the teak tree (Tectona grandis), which grows to a height of 45 metres (147. Teak ( Tectona) is a genus of tropical Hardwood Trees in the family Verbenaceae, native to the south and southeast of Asia 6 ft). It has a spread root system with a spread of 5 m and a biomass of 4 times that of the trunk; its penetration into the soil is 1. 25 metres (4. 10 ft) and has no tap root. When planted near a building, its height helps in catching the oncoming lightning leader, and the high biomass of the root system helps in dissipation of the lightning charges. ^[66]

Lightning currents have a very fast risetime, on the order of 40 kA per microsecond. In Electronics, when describing a Voltage or current Step function, rise time (also risetime) refers to the time required for a signal Hence, conductors of such currents exhibit marked skin effect, causing most of the currents to flow through the conductor skin. The skin effect is the tendency of an alternating electric current (AC to distribute itself within a conductor so that the current density near the surface of the ^[67] The effective resistance of the conductor is consequently very high and therefore, the conductor skin gets heated up much more than the conductor core. When a tree acts as a natural lightning conductor, due to skin effect most of the lightning currents flow through the skin of the tree and the sap wood. As a result, the skin gets burnt and may even peel off. The moisture in the skin and the sap wood evaporates instantaneously and may get split. If the tree struck by lightning is a teak tree (single stemmed with branches) it may not be completely destroyed since only the tree skin and a branch may be affected; the major parts of the tree may be saved from complete destruction due to lightning currents. But if the tree involved is a coconut tree it may be completely destroyed by the lightning currents. The Coconut Palm ( Cocos nucifera) is a member of the Family Arecaceae (palm family

Lightning-induced magnetism

Lightning induced remanent magnetization (LIRM) mapped during a magnetic field gradient survey of an archaeological site located in Wyoming (USA)

The movement of electrical charges produces a magnetic field (see Electromagnetism). Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of The intense currents of a lightning discharge create a fleeting but very strong magnetic field. Where the lightning current path passes through rock, soil, or metal these materials can become permanently magnetized. This effect is known as lightning-induced remanent magnetism, or LIRM. These currents follow the least resistive path, often horizontally near the surface^[68] but sometimes vertically, where faults, ore bodies, or ground water offers a less resistive path. ^[69] Lightning-induced Magnetic anomalies can be mapped in the ground,^[70][71] and analysis of magnetized materials can confirm lightning was the source of the magnetization^[72] and provide an estimate of the peak current of the lightning discharge. ^[73]

Records and locations

On average, lightning flashes occur on earth about 100 times every second. 80% of these flashes are in-cloud and 20% are cloud-to-ground. For most landmasses, lightning strikes most often during the summer, limiting the strike numbers. The spot with the most lightning lies deep in the mountains of eastern Democratic Republic of the Congo, near the small village of Kifuka which has an elevation of 3,200 feet (975 m). The Democratic Republic of the Congo (République démocratique du Congo often referred to as DR Congo, DRC or RDC, and formerly known or referred to Thunderbolts pelt this land, and each year on average, 158 bolts occur over each square kilometer (equivalent to 10 city-blocks square). ^[74] Singapore has one of the highest rates of lightning activity in the world. Singapore ^[75] The city of Teresina in northern Brazil has the third-highest rate of occurrences of lightning strikes in the world. Teresina is the capital and largest city of the Brazilian state of Piauí and the only inland capital in the northeastern region of the |utc_offset = -2 to -4 |time_zone_DST = BRST |utc_offset_DST = -2 to -5 |cctld The surrounding region is referred to as the Chapada do Corisco ("Flash Lightning Flatlands"). ^[76] In the US, Central Florida sees more lightning than any other area. Florida ( is a state located in the southeastern region of the United States, bordering Alabama to the northwest and Georgia to the For example, in what is called "Lightning Alley", an area from Tampa, to Orlando, there are as many as 50 strikes per square mile (about 20 per km²) per year. Orlando is a major City in central Florida, USA and is the County seat of Orange County Florida. ^[77][78] The Empire State Building is struck by lightning on average 23 times each year, and was once struck 8 times in 24 minutes. The Empire State Building is a 102-story Art Deco Skyscraper in New York City at the intersection of Fifth Avenue and West 34th Street ^[79]

Roy Sullivan held a Guinness World Record after surviving 7 different lightning strikes across 35 years. Roy Cleveland Sullivan ( February 7, 1912 &ndash September 28, 1983) was a U Guinness World Records, known until 2000 as The Guinness Book of Records (and in previous U ^[80]

In July 2007, lightning killed up to 30 people when it struck a remote mountain village Ushari Dara in northwestern Pakistan. Pakistan () officially the Islamic Republic of Pakistan, is a country located in South Asia, Southwest Asia, Middle East and ^[81]

Lightning can also strike indoor pools, directed into the pump by electrical circuits from outdoor power poles. Such strikes could potentially kill people who are swimming or walking on wet floors around a pool. In 2000, lightning killed two boys in an outdoor pool in Florida. ^[82]

A single lightning strike can have a potential of a billion volts and deliver 100,000 amperes of current. If a bolt directly hits a marine animal swimming on the surface, it will undoubtedly hurt or kill the animal. Lightning strikes have killed or injured people on the surface more than 30 yards away. ^[83]

On 31 October 2005, sixty-eight dairy cows, all in full milk, died on a farm at Fernbrook on the Waterfall Way near Dorrigo, New South Wales after being struck by lightning. The Waterfall Way is a road and State Highway 78 in New South Wales, Australia. Dorrigo is a small town located on the Waterfall Way in northern New South Wales, Australia. Three others were paralysed for several hours but they later made a full recovery. The cows were sheltering under a tree when it was struck by lightning and the electricity spread onto the surrounding soil killing the animals. ^[84]

Lightning rarely strikes the open ocean, although some sea regions are lightning "hot spots. " Winter storms passing off the east coast of the United States often erupt with electrical activity when they cross the warm waters of the Gulf Stream. ^[85]The Gulf Stream, for example, has roughly as many lightning strikes as the southern plains of the USA.

Lightning detection

Lightning discharges generate a wide range of electromagnetic radiations, including radio-frequency pulses. The times at which a pulse from a given lightning discharge arrive at several receivers can be used to locate the source of the discharge. The United States federal government has constructed a nation-wide grid of such lightning detectors, allowing lightning discharges to be tracked in real time throughout the continental U. S. ^[86][87]

In addition to ground-based lightning detection, several instruments aboard satellites have been constructed to observe lightning distribution. These include the Optical Transient Detector (OTD), aboard OrbView-1 satellite launched on April 3, 1995, and the subsequent Lightning Imaging Sensor (LIS) aboard TRMM launched on November 28, 1997. The Tropical Rainfall Measuring Mission ( TRMM) is a joint Space mission between NASA and the Japan Aerospace Exploration Agency (JAXA designed ^[88][89][90]

Most spectacular lightning strike incidences

Several spectacular lightning incidences have occurred, either with people killed or great damage caused. The following incomplete list shows some cases:

• 1902: A lightning strike damaged the upper section of the Eiffel Tower, requiring the reconstruction of its top^[91]
• December 8th, 1963: Pan Am Flight 214 crashed as result of a lightning strike, and 81 people were killed. The Eiffel Tower (Tour Eiffel /tuʀ ɛfɛl/ is an Iron Tower built Pan Am Flight 214, a Boeing 707-121 registered as, was a domestic scheduled passenger flight from Baltimore to Philadelphia, which crashed on
• July 1970, the central mast of the Orlunda radio transmitter collapsed after a lightning strike destroyed its basement insulator. The Longwave transmitter Orlunda was a broadcast transmission facility for Longwave at Orlunda, Sweden near Motala, which
• December 24th, 1971: LANSA Flight 508 crashed as a result of lightning in Peru, with 91 people killed. LANSA Flight 508 was a Lockheed Electra L-188A Turboprop, registered OB-R-941 operated as a scheduled domestic passenger flight by Lineas Aéreas Nacionales

In culture

As expressions and symbols

The expression "Lightning never strikes twice [in the same place]" is similar to "Opportunity never knocks twice" in the vein of a "once in a lifetime" opportunity, i. e. , something that is generally considered improbable. Lightning occurs frequently and more so in specific areas. Lightning is an atmospheric discharge of Electricity, which typically occurs during Thunderstorms and sometimes during volcanic eruptions or Lightning is an atmospheric discharge of Electricity, which typically occurs during Thunderstorms and sometimes during volcanic eruptions or Since various factors alter the probability of strikes at any given location, repeat lightning strikes have a very low probability (but are not impossible). Lightning is an atmospheric discharge of Electricity, which typically occurs during Thunderstorms and sometimes during volcanic eruptions or Probability is the likelihood or chance that something is the case or will happen ^[79][92] Similarly, "A bolt from the blue" refers to something totally unexpected.

In French and Italian, the expression for "Love at first sight" is Coup de foudre and Colpo di fulmine, respectively, which literally translated means "Bolt of lightning". French ( français,) is a Romance language spoken around the world by 118 million people as a native language and by about 180 to 260 million people Italian ( or lingua italiana) is a Romance language spoken by about 63 million people as a First language, primarily in Italy. Some European languages have a separate word for lightning which strikes the ground (as opposed to lightning in general); often it is a cognate of the English word "rays". Cognates in Linguistics are words that have a common origin They may occur within a language such as shirt and skirt as two English words descended from The name of New Zealand's most celebrated thoroughbred horse, Phar Lap, derives from the shared Zhuang and Thai word for lightning. New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island The Thoroughbred is a horse breed For the Computer software, see Phar Lap (company. Phar Lap, a giant chestnut Thoroughbred Gelding, is considered Thai (th ภาษาไทย, transcription: phasa thai, transliteration:; pʰāːsǎːtʰāj is the national and

The bolt of lightning in heraldry is called a thunderbolt and in Sanskrit is called Vajra and is shown as a zigzag with non-pointed ends. Heraldry in its most general sense encompasses all matters relating to the duties and responsibilities of officers of arms. A thunderbolt is a traditional expression for a discharge of Lightning or a symbolic representation thereof Sanskrit (sa संस्कृता वाक् saṃskṛtā vāk, for short sa संस्कृतम् saṃskṛtam) is a historical Vajra ( Devanagari: वज्र Tibetan: dorje ( is a Sanskrit word meaning both Thunderbolt and Diamond This symbol usually represents power and speed; and thus has been used to represent the Hindu god Indra, as well as many advertisements which use such symbol to describe their product. Hindu mythology is the large body of Mythology related to Hinduism, notably as contained in Sanskrit literature, such as the Sanskrit epics and Indra ( Sanskrit: इन्द्र or इंद्र Indra, Malay: Indera, Thai: พระอินทร์ Phra-Intra It is also distinguished from the "fork of lightning".

The lightning bolt shape was a symbol of male humans among the Native Americans such as the Apache in the American Old West. The musical instrument is spelled Cymbal. A symbol is something --- such as an object, Picture, written word a sound a piece Native Americans in the United States are the indigenous peoples from the regions of North America now encompassed by the continental United States

See also

References

Sources

External links

• How to survive in a lightning storm A guide for children and youth
• How Lightning Works at HowStuffWorks
• "1.21 Gigawatts!" Lightning safety and first-aid in the backcountry
• dmoz: Thunderstorms and Lightning
• Lightning Safety Page - National Weather Service Pueblo Colorado Citat: ". . . This is known as a "side flash". Many people who are "struck" by lightning are not hit directly by the main lightning channel, but are affected by the side flash. . . "
• Colorado Lightning Resource Center
• Webarchive: April 25, 1997 Sandia-led research may zap old beliefs about lightning protection at critical facilities; Triggered lightning tests leading to safer storage bunkers
• 2003-11-06, ScienceDaily: Thunderstorm Research Shocks Conventional Theories; Florida Tech Physicist Throws Open Debate On Lightning's Cause
• Austrian Lightning Detection and Information System
• European Cooperation for Lightning Detection
• United States Precision Lightning Network - Live lightning data map
• NASA Finds Lightning Clears Safe Zone in Earth's Radiation Belt
• NOAA: What is Lightning?
• National Geographic Lightning Simulator
• Live storm data and sferics for southern England generated by data recorded by a weather station at Newport, Isle of Wight, UK [2]
• Lightning strikes governed by moving cloud layers - the first theory to fully explain lightning formation and dynamics, New Scientist, 23 March 2008
• Social & Economic Costs of Lightning from "NOAA Socioeconomics" website initiative

Jets, sprites & elves

• Homepage of the Eurosprite campaign, itself part of the CAL (Coupled Atmospheric Layers) research group
• March 2, 1999, University of Houston: UH Physicists Pursue Lightning-Like Mysteries Quote: ". . . Red sprites and blue jets are brief but powerful lightning-like flashes that appear at altitudes of 40-100 km (25-60 miles) above thunderstorms. . . "
• Ground and Balloon-Borne Observations of Sprites and Jets
• Barrington-Leigh, C. P. , "Elves : Ionospheric Heating By the Electromagnetic Pulses from Lightning (A primer)". Space Science Lab, Berkeley.
• "Darwin Sprites '97". Space Physics Group, University of Otago.
• Barrington-Leigh, Christopher, "VLF Research at Palmer Station".
• Sprites, jets and TLE pictures and articles
• Juha's and Aleksi's research of the late 90s