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Megacryometeor
A megacryometeor is a very large chunk of ice which, despite sharing many textural, hydro-chemical, and isotopic features found in large hailstones, is formed under unusual atmospheric conditions which clearly differ from those of the cumulonimbus cloud scenario (i.e. clear-sky conditions). They are sometimes called huge hailstones, but do not need to form under thunderstorm conditions unlike hailstorms. Jesús Martínez-Frías, a planetary geologist and astrobiologist at Institute of Geosciences (, IGEO) in the Spanish National Research Council (, CSIC) in Madrid, pioneered research into megacryometeors. Mass and size More than 50 megacryometeors have been recorded since the year 2000. They vary in mass between to several tens of kilograms. One in Brazil weighed in at more than . Chunks about in size also fell in Scotland on 13 August 1849. Formation The process that creates megacryometeors is not completely understood yet, mainly with respect to the atmospheric dynamics neces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hail
Hail is a form of solid Precipitation (meteorology), precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailstone. Ice pellets generally fall in cold weather, while hail growth is greatly inhibited during low surface temperatures. Unlike other forms of ice, water ice precipitation, such as graupel (which is made of rime ice), ice pellets (which are smaller and Transparency and translucency, translucent), and snow (which consists of tiny, delicately crystalline flakes or needles), hailstones usually measure between and in diameter. The METAR reporting code for hail or greater is GR, while smaller hailstones and graupel are coded GS. Hail is possible during most thunderstorms (as it is produced by cumulonimbus), as well as within of the parent storm. Hail formation requires environments of strong, upward motion of air within the parent thunderst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmosphere
An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere is the outer region of a star, which includes the layers above the opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules. The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and trace gases. Most organisms use oxygen for respiration; lightning and bacteria perform nitrogen fixation which produces ammonia that is used to make nucleotides and amino acids; plants, algae, and cyanobacteria use carbon dioxide for photosynthesis. The layered composition of the atmosphere minimises the harmful effects of sunlight, ultraviolet radiation, solar wind, and cosmic rays and thus protects the organisms from genetic damage. The curr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impact Crater
An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Impact craters are typically circular, though they can be elliptical in shape or even irregular due to events such as landslides. Impact craters range in size from microscopic craters seen on lunar rocks returned by the Apollo Program to simple bowl-shaped depressions and vast, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth. Impact craters are the dominant geographic features on many solid Solar System objects including the Moon, Mercury (planet), Mercury, Callisto (moon), Callisto, Ganymede (moon), Ganymede, and most small moons and asteroids. On other planet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteor
A meteor, known colloquially as a shooting star, is a glowing streak of a small body (usually meteoroid) going through Earth's atmosphere, after being heated to incandescence by collisions with air molecules in the upper atmosphere, creating a streak of light via its rapid motion and sometimes also by shedding glowing material in its wake. Although a meteor may seem to be a few thousand feet from the Earth, meteors typically occur in the mesosphere at altitudes from . The root word ''meteor'' comes from the Ancient Greek, Greek ''meteōros'', meaning "high in the air". Millions of meteors occur in Earth's atmosphere daily. Most meteoroids that cause meteors are about the size of a grain of sand, i.e. they are usually millimeter-sized or smaller. Meteoroid sizes can be calculated from their mass and density which, in turn, can be estimated from the observed meteor trajectory in the upper atmosphere. Meteors may occur in meteor shower, showers, which arise when Earth passes throu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratosphere
The stratosphere () is the second-lowest layer of the atmosphere of Earth, located above the troposphere and below the mesosphere. The stratosphere is composed of stratified temperature zones, with the warmer layers of air located higher (closer to outer space) and the cooler layers lower (closer to the planetary surface of the Earth). The increase of temperature with altitude is a result of the absorption of the Sun's ultraviolet (UV) radiation by the ozone layer, where ozone is exothermically photolyzed into oxygen in a cyclical fashion. This temperature inversion is in contrast to the troposphere, where temperature decreases with altitude, and between the troposphere and stratosphere is the tropopause border that demarcates the beginning of the temperature inversion. Near the equator, the lower edge of the stratosphere is as high as , at mid-latitudes around , and at the poles about . Temperatures range from an average of near the tropopause to an average of ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropopause
The tropopause is the atmospheric boundary that demarcates the lowest two layers of the atmosphere of Earth – the troposphere and stratosphere – which occurs approximately above the equatorial regions, and approximately above the polar regions. Definition Rising from the planetary surface of the Earth, the tropopause is the atmospheric level where the air ceases to become cool with increased altitude and becomes dry, devoid of water vapor. The tropopause is the boundary that demarcates the troposphere below from the stratosphere above, and is part of the atmosphere where there occurs an abrupt change in the environmental lapse rate (ELR) of temperature, from a positive rate (of decrease) in the troposphere to a negative rate in the stratosphere. The tropopause is defined as the lowest level at which the lapse rate decreases to 2°C/km or less, provided that the average lapse-rate, between that level and all other higher levels within 2.0 km does not exceed 2°C/km. The trop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Ice (aviation)
In aviation, blue ice is frozen sewage material that has leaked mid-flight from commercial aircraft lavatory waste systems. It is a mixture of human biowaste and liquid disinfectant that freezes at high altitude. The name comes from the blue color of the disinfectant. Airlines are not allowed to dump their waste tanks mid-flight, and pilots have no mechanism by which to do so; however, leaks sometimes do occur from a plane's septic tank. Danger of ground impact There were at least 27 documented incidents of blue ice impacts in the United States between 1979 and 2003. These incidents typically happen under airport landing paths as the mass warms sufficiently to detach from the plane during its descent. A rare incident of falling blue ice causing damage to the roof of a home was reported on October 20, 2006, in Chino, California. A similar incident was reported in Leicester, UK, in 2007. Other documented incidents include: * In 1971, a chunk of ice from an aircraft tore a large hol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disinfectant
A disinfectant is a chemical substance or compound used to inactivate or destroy microorganisms on inert surfaces. Disinfection does not necessarily kill all microorganisms, especially resistant bacterial spores; it is less effective than sterilization, which is an extreme physical or chemical process that kills all types of life. Disinfectants are generally distinguished from other antimicrobial agents such as antibiotics, which destroy microorganisms within the body, and antiseptics, which destroy microorganisms on living tissue. Disinfectants are also different from biocides—the latter are intended to destroy all forms of life, not just microorganisms. Disinfectants work by destroying the cell wall of microbes or interfering with their metabolism. It is also a form of decontamination, and can be defined as the process whereby physical or chemical methods are used to reduce the amount of pathogenic microorganisms on a surface. Disinfectants can also be used to dest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rain
Rain is a form of precipitation where water drop (liquid), droplets that have condensation, condensed from Water vapor#In Earth's atmosphere, atmospheric water vapor fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. It provides water for hydroelectricity, hydroelectric power plants, crop irrigation, and suitable conditions for many types of ecosystems. The major cause of rain production is moisture moving along three-dimensional zones of temperature and moisture contrasts known as weather fronts. If enough moisture and upward motion is present, precipitation falls from convection, convective clouds (those with strong upward vertical motion) such as cumulonimbus (thunder clouds) which can organize into narrow rainbands. In mountainous areas, heavy precipitation is possible where upslope flow is maximized within windward sides of the terrain at elevation which forces moist air to condense and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Brazil
Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population, seventh-largest by population, with over 212 million people. The country is a federation composed of 26 Federative units of Brazil, states and a Federal District (Brazil), Federal District, which hosts the capital, Brasília. List of cities in Brazil by population, Its most populous city is São Paulo, followed by Rio de Janeiro. Brazil has the most Portuguese-speaking countries, Portuguese speakers in the world and is the only country in the Americas where Portuguese language, Portuguese is an Portuguese-speaking world, official language. Bounded by the Atlantic Ocean on the east, Brazil has a Coastline of Brazil, coastline of . Covering roughly half of South America's land area, it Borders of Brazil, borders all other countries and ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madrid
Madrid ( ; ) is the capital and List of largest cities in Spain, most populous municipality of Spain. It has almost 3.5 million inhabitants and a Madrid metropolitan area, metropolitan area population of approximately 7 million. It is the Largest cities of the European Union by population within city limits, second-largest city in the European Union (EU), and its wikt:monocentric, monocentric Madrid metropolitan area, metropolitan area is the List of metropolitan areas in Europe by population, second-largest in the EU.United Nations Department of Economic and Social AffairWorld Urbanization Prospects (2007 revision), (United Nations, 2008), Table A.12. Data for 2007. The municipality covers geographical area. Madrid lies on the Manzanares (river), River Manzanares in the central part of the Iberian Peninsula at about above mean sea level. The capital city of both Spain and the surrounding Community of Madrid, autonomous community of Madrid (since 1983), it is also th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
