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. The windstorm 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. Tornadoes come in many shapes and sizes, and they are often visible in the form of a condensation funnel originating from the base of a cumulonimbus cloud, with a cloud of rotating debris and dust beneath it. Most tornadoes have wind speeds less than 110 miles per hour (180 km/h), are about 250 feet (80 m) across, and travel a few miles (several kilometers) before dissipating. The most extreme tornadoes can attain wind speeds of more than 300 miles per hour (480 km/h), are more than two miles (3 km) in diameter, and stay on the ground for dozens of miles (more than 100 km).Various types of tornadoes include the multiple vortex tornado, landspout, and waterspout. Waterspouts are characterized by a spiraling funnel-shaped wind current, connecting to a large cumulus or cumulonimbus cloud. They are generally classified as non-supercellular tornadoes that develop over bodies of water, but there is disagreement over whether to classify them as true tornadoes. These spiraling columns of air frequently develop in tropical areas close to the equator and are less common at high latitudes. Other tornado-like phenomena that exist in nature include the gustnado, dust devil, fire whirl, and steam devil.
Tornadoes occur most frequently in North America (particularly in central and southeastern regions of the United States colloquially known as tornado alley; the USA and Canada have by far the most tornadoes of any countries in the world), South Africa, much of Europe (except Spain, most of the Alps, Balkans, and northern Scandinavia), western and eastern Australia, New Zealand, Bangladesh and adjacent eastern India, Japan, Philippines, and southeastern South America (Uruguay and Argentina). Tornadoes can be detected before or as they occur through the use of Pulse-Doppler radar by recognizing patterns in velocity and reflectivity data, such as hook echoes or debris balls, as well as through the efforts of storm spotters.
Contribution may refer to:
Contribution (album), by Mica Paris (1990)
"Contribution" (song), title song from the album
Contribution (law), an agreement between defendants in a suit to apportion liability
Contributions, a vital goal of fundraising
Contribution, a 1976 album by Shawn PhillipsEnglish usually refers to:
English language
English peopleEnglish may also refer to:A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically officially authorized and maintained by a sovereign state, with its members identifiable by their distinct military uniform. It may consist of one or more military branches such as an army, navy, air force, space force, marines, or coast guard. The main task of the military is usually defined as defence of the state and its interests against external armed threats.
In broad usage, the terms armed forces and military are often treated as synonymous, although in technical usage a distinction is sometimes made in which a country's armed forces may include both its military and other paramilitary forces. There are various forms of irregular military forces, not belonging to a recognized state; though they share many attributes with regular military forces, they are less often referred to as simply military.
A nation's military may function as a discrete social subculture, with dedicated infrastructure such as military housing, schools, utilities, logistics, hospitals, legal services, food production, finance, and banking services. Beyond warfare, the military may be employed in additional sanctioned and non-sanctioned functions within the state, including internal security threats, population control, the promotion of a political agenda, emergency services and reconstruction, protecting corporate economic interests, social ceremonies and national honour guards.The profession of soldiering as part of a military is older than recorded history itself. Some of the most enduring images of classical antiquity portray the power and feats of its military leaders. The Battle of Kadesh in 1274 BC was one of the defining points of Pharaoh Ramses II's reign, and his monuments commemorate it in bas-relief. A thousand years later, the first emperor of unified China, Qin Shi Huang, was so determined to impress the gods with his military might that he had himself buried with an army of terracotta soldiers.
The Romans paid considerable attention to military matters, leaving to posterity many treatises and writings on the subject, as well as many lavishly carved triumphal arches and victory columns.Dominance may refer to: