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Lightning
Lightning is a natural phenomenon consisting of electrostatic discharges occurring through the atmosphere between two electrically charged regions. One or both regions are within the atmosphere, with the second region sometimes occurring on the land, ground. Following the lightning, the regions become partially or wholly electrically neutralized. Lightning involves a near-instantaneous release of energy on a scale averaging between 200 megajoules and 7 gigajoules. The air around the lightning flash rapidly heats to temperatures of about . There is an emission of electromagnetic radiation across a wide range of wavelengths, some visible as a bright flash. Lightning also causes thunder, a sound from the shock wave which develops as heated gases in the vicinity of the discharge experience a sudden increase in pressure. The most common occurrence of a lightning event is known as a thunderstorm, though they can also commonly occur in other types of energetic weather systems, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Lightning Strike
A lightning strike or lightning bolt is a lightning event in which an electric discharge takes place 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 25% 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.Cooray, Vernon. (2014). Lightning Flash (2nd Edition) - 1. Charge Structure and Geographical Variation of Thunderclouds. Page 4. Institution of Engineering and Technology. 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 lightn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Ball Lightning
Ball lightning is a rare and unexplained phenomenon described as Luminosity, luminescent, spherical objects that vary from pea-sized to several meters in diameter. Though usually associated with thunderstorms, the observed phenomenon is reported to last considerably longer than the split-second flash of a lightning strike, lightning bolt, and is a phenomenon distinct from St. Elmo's fire and will-o'-the-wisp. Some 19th-century reports describe balls that eventually explode and leave behind an odor of sulfur. Descriptions of ball lightning appear in a variety of accounts over the centuries and have received attention from scientists. An optical spectrum of what appears to have been a ball lightning event was published in January 2014 and included a video at high frame rate. Nevertheless, scientific data on ball lightning remain scarce. Although laboratory experiments have produced effects that are visually similar to reports of ball lightning, how these relate to the supposed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Volcano Lightning
Volcanic lightning is an electrical discharge caused by a volcanic eruption rather than from an ordinary thunderstorm. Volcanic lightning arises from colliding, fragmenting particles of volcanic ash (and sometimes ice), which generate static electricity within the volcanic plume, leading to the name dirty thunderstorm. Moist convection currents and ice formation also drive the eruption plume dynamics and can trigger volcanic lightning. Unlike ordinary thunderstorms, volcanic lightning can also occur when there are no ice crystals in the ash cloud. The earliest recorded observations of volcanic lightning are from Pliny the Younger, describing the eruption of Mount Vesuvius in 79 AD, "There was a most intense darkness rendered more appalling by the fitful gleam of torches at intervals obscured by the transient blaze of lightning." The first studies of volcanic lightning were also conducted at Mount Vesuvius by Luigi Palmieri who observed the eruptions of 1858, 1861, 1868, and 18 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Thunderstorm
A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustics, acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are sometimes called thundershowers. Thunderstorms occur in cumulonimbus clouds. They are usually accompanied by strong winds and often produce Heavy rain (meteorology), heavy rain and sometimes Thundersnow, snow, Ice pellets, sleet, or hail, but some thunderstorms can produce little or Dry thunderstorm, no precipitation at all. Thunderstorms may thunderstorm training, line up in a series or become a rainband, known as a squall line. Strong or #Severe thunderstorms, severe thunderstorms include some of the most dangerous weather phenomena, including large hail, strong winds, and tornadoes. Some of the most persistent severe thunderstorms, known as supercells, rotate as do cyclones. While most thunderstorms move with the mean wind flow thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Thunder
Thunder is the sound caused by lightning. Depending upon the distance from and nature of the lightning, it can range from a long, low rumble to a sudden, loud crack. The sudden increase in temperature and hence pressure caused by the lightning produces rapid Thermal expansion, expansion of the air in the path of a Lightning strike, lightning bolt. In turn, this expansion of air creates a Shock wave, sonic shock wave, often referred to as a "thunderclap" or "peal of thunder". The scientific study of thunder is known as ''brontology'' and the irrational fear (phobia) of thunder is called ''brontophobia''. Etymology The ''d'' in Modern English ''thunder'' (from earlier Old English ''þunor'') is epenthetic, and is now found as well in Modern Dutch ''donder'' (cf. Middle Dutch ''donre''; also Old Norse ''þorr'', Old Frisian ''þuner'', Old High German ''donar'', all ultimately descended from Proto-Germanic *''þunraz''). In Latin the term was ''tonare'' "to thunder". The name of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Heat Lightning
Heat lightning (not to be confused with dry thunderstorms, which are also often called dry lightning) is a misnomer used for the faint flashes of lightning on the horizon or other clouds from distant thunderstorm A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustics, acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorm ...s that do not appear to have accompanying sounds of thunder. The actual phenomenon that is sometimes called heat lightning is simply cloud-to-ground lightning that occurs very far away, with thunder that dissipates before it reaches the observer. At night, it is possible to see the flashes of lightning from very far distances, up to , but the sound does not carry that far. In the United States, lightning is especially common in Florida, which is considered the deadliest state for lightning strikes in the country. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Dry Lightning
A dry thunderstorm is a thunderstorm that produces thunder and lightning, but where all or most of its precipitation evaporates before reaching the ground. Dry lightning refers to lightning strikes occurring in this situation. Both are so common in the American West that they are sometimes used interchangeably. Dry thunderstorms occur essentially in dry conditions, and their lightning is a major cause of wildfires. Because of that, the United States National Weather Service, and other agencies around the world, issue forecasts for its likelihood over large areas. Where dry thunderstorms occur Dry thunderstorms generally occur in deserts or places where the lower layers of the atmosphere usually contain little water vapor. Any precipitation that falls from elevated thunderstorms can be entirely evaporated as it falls through the lower dry layers. They are common during the summer months across much of western North America and other arid areas. The shaft of precipitation that ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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National Severe Storms Laboratory
The National Severe Storms Laboratory (NSSL) is a National Oceanic and Atmospheric Administration (NOAA) weather research laboratory under the Office of Oceanic and Atmospheric Research. It is one of seven NOAA Research Laboratories (RLs). NSSL studies weather radar, tornadoes, flash floods, lightning, damaging winds, hail, and winter weather out of Norman, Oklahoma, using various techniques and tools in their HWT, or Hazardous Weather Testbed. NSSL meteorologists developed the first doppler radar for the purpose of meteorological observation, and contributed to the development of the NEXRAD (WSR-88D). NSSL has a partnership with the Cooperative Institute for Severe and High-Impact Weather Research and Operations (CIWRO) at the University of Oklahoma that enables collaboration and participation by students and visiting scientists in performing research. The Lab also works closely with the Storm Prediction Center (SPC) and the National Weather Service Norman, Oklahoma, National ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Cumulonimbus Cloud
Cumulonimbus () is a dense, towering, vertical cloud, typically forming from water vapor condensing in the lower troposphere that builds upward carried by powerful buoyant air currents. Above the lower portions of the cumulonimbus the water vapor becomes ice crystals, such as snow and graupel, the interaction of which can lead to hail and to lightning formation, respectively. When causing thunderstorms, these clouds may be called thunderheads. Cumulonimbus can form alone, in clusters, or along squall lines. These clouds are capable of producing lightning and other dangerous severe weather, such as tornadoes, hazardous winds, and large hailstones. Cumulonimbus progress from overdeveloped cumulus congestus clouds and may further develop as part of a supercell. Cumulonimbus is abbreviated as Cb. Description Towering cumulonimbus clouds are typically accompanied by smaller cumulus clouds. The cumulonimbus base may extend several kilometres (miles) across, or be a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Global Atmospheric Electrical Circuit
A global atmospheric electrical circuit is the continuous movement of atmospheric charge carriers, such as ions, between an upper conductive layer (often an ionosphere) and surface. The global circuit concept is closely related to atmospheric electricity, but not all atmospheres necessarily have a global electric circuit. The basic concept of a global circuit is that through the balance of thunderstorms and fair weather, the atmosphere is subject to a continual and substantial electrical current. Principally, thunderstorms throughout the world carry ''negative'' charges to the ground, which is then discharged gradually through the air away from the storms, in conditions that are referred to as "fair weather". This atmospheric circuit is central to the study of atmospheric physics and meteorology. The global electrical circuit is also relevant to the study of human health and air pollution, due to the interaction of ions and aerosols. The effects of climate change and temperature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Electrostatic Discharge
Electrostatic discharge (ESD) is a sudden and momentary flow of electric current between two differently-charged objects when brought close together or when the dielectric between them breaks down, often creating a visible electric spark, spark associated with the static electricity between the objects. ESD can create spectacular electric sparks (lightning, with the accompanying sound of thunder, is an example of a large-scale ESD event), but also less dramatic forms, which may be neither seen nor heard, yet still be large enough to cause damage to sensitive electronic devices. Electric sparks require a field strength above approximately 4 million V/m in air, as notably occurs in lightning strikes. Other forms of ESD include corona discharge from sharp electrodes, brush discharge from blunt electrodes, etc. ESD can cause harmful effects of importance in industry, including explosions in gas, fuel vapor and coal dust, as well as failure of solid state electronics components such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |