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 expansion of the air in the path of a lightning bolt. In turn, this expansion of air creates a 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.
A tornado is a violently rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the word cyclone is used in meteorology to name a weather system with a low-pressure area in the center around which, from an observer looking down toward the surface of the Earth, winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern.
In electromagnetism, an electric discharge is the release and transmission of electricity in an applied electric field through a medium such as a gas (ie., an outgoing flow of electric current through a non-metal medium). The properties and effects of electric discharges are useful over a wide range of magnitudes. Tiny pulses of current are used to detect ionizing radiation in a Geiger–Müller tube. A low steady current can be used to illustrate the spectrum of gases in a gas-filled tube.
Perkūnas (Perkūnas, Pērkons, Old Prussian: Perkūns, Perkunos, Yotvingian: Parkuns, Latgalian: Pārkiuņs) was the common Baltic god of thunder, and the second most important deity in the Baltic pantheon after Dievas. In both Lithuanian and Latvian mythology, he is documented as the god of sky, thunder, lightning, storms, rain, fire, war, law, order, fertility, mountains, and oak trees. Perkwunos The name continues PIE *, cognate to *, a word for "oak", "fir" or "wooded mountain".
A lightning rod or lightning conductor (British English) is a metal rod mounted on a structure and intended to protect the structure from a lightning strike. If lightning hits the structure, it will preferentially strike the rod and be conducted to ground through a wire, instead of passing through the structure, where it could start a fire or cause electrocution. Lightning rods are also called finials, air terminals, or strike termination devices. In a lightning protection system, a lightning rod is a single component of the system.
Extremely low frequency (ELF) is the ITU designation for electromagnetic radiation (radio waves) with frequencies from 3 to 30 Hz, and corresponding wavelengths of 100,000 to 10,000 kilometers, respectively. In atmospheric science, an alternative definition is usually given, from 3 Hz to 3 kHz. In the related magnetosphere science, the lower frequency electromagnetic oscillations (pulsations occurring below ~3 Hz) are considered to lie in the ULF range, which is thus also defined differently from the ITU radio bands.
Ukko (ˈukːo), Äijä ˈæi̯jæ or Äijö ˈæi̯jø (Finnish for 'male grandparent', 'grandfather', 'old man'), parallel to Uku in Estonian mythology, is the god of the sky, weather, harvest, and thunder in Finnish mythology. Ukkonen, the Finnish word for thunder, is the diminutive form of the name Ukko. Unto Salo believes that Ilmari, another Finnic sky god, is the origin of Ukko, but that as Ukko Ilmari experienced very significant, although far from total, influence from the Indo-European sky god especially in the form of Thor.
A thunderbolt or lightning bolt is a symbolic representation of lightning when accompanied by a loud thunderclap. In Indo-European mythology, the thunderbolt was identified with the 'Sky Father'; this association is also found in later Hellenic representations of Zeus and Vedic descriptions of the vajra wielded by the god Indra. It may have been a symbol of cosmic order, as expressed in the fragment from Heraclitus describing "the Thunderbolt that steers the course of all things".
In meteorology, an updraft is a small-scale current of rising air, often within a cloud. Localized regions of warm or cool air will exhibit vertical movement. A mass of warm air will typically be less dense than the surrounding region, and so will rise until it reaches air that is either warmer or less dense than itself. The converse will occur for a mass of cool air, and is known as subsidence. This movement of large volumes of air, especially when regions of hot, wet air rise, can create large clouds, and is the central source of thunderstorms.
Space charge is an interpretation of a collection of electric charges in which excess electric charge is treated as a continuum of charge distributed over a region of space (either a volume or an area) rather than distinct point-like charges. This model typically applies when charge carriers have been emitted from some region of a solid—the cloud of emitted carriers can form a space charge region if they are sufficiently spread out, or the charged atoms or molecules left behind in the solid can form a space charge region.
