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33-530: The size of New Zealand, it re-occurred each winter between 1974 and 1976. These were the first three austral winters observed by the Nimbus 5 Electrically Scanning Microwave Radiometer (ESMR). From 1976 to 2015, this polynya was rarely observed. The polynya reoccurred in 2016, and has since appeared in 2017. The 2010s occurrence has been smaller than the 1970s occurrence, being about the size of Maine in 2017, or roughly 80,000 km (31,000 sq mi). Since

66-435: A correct description of the source of stratospheric ozone and its ability to generate heat within the stratosphere; he also wrote that ozone may be destroyed by reacting with atomic oxygen, making two molecules of molecular oxygen. We now know that there are additional ozone loss mechanisms and that these mechanisms are catalytic, meaning that a small amount of the catalyst can destroy a great number of ozone molecules. The first

99-601: A magnetic tape so they could be transmitted later. ESMR was used for mapping the microwave radiation from Earth's surface. This information was used to measure the water content of clouds, and to observe sea ice. It was also used to test the use of microwaves to measure soil moisture. The antenna system was deployed after launch, and controlled by an onboard computer. For measuring the thermal emission characteristics of Earth's surface and sea temperatures. A scanning mirror rotated ten times per second to sense sections 800 km wide. SCMR malfunctioned soon after launch. THIR

132-484: A phenomenon called Rossby-wave pumping. An interesting feature of stratospheric circulation is the quasi-biennial oscillation (QBO) in the tropical latitudes, which is driven by gravity waves that are convectively generated in the troposphere . The QBO induces a secondary circulation that is important for the global stratospheric transport of tracers, such as ozone or water vapor . Another large-scale feature that significantly influences stratospheric circulation

165-529: A resolution of 32 km . The SCR had three objectives: to observe the global atmospheric temperature structure, to observe the distribution of water vapor, and to measure the density of ice crystals in cirrus clouds . Its sensing resolution was about 25 km . NEMS was used to demonstrate the use of microwave sensors for measuring tropospheric temperature profiles, water content in clouds, and surface temperature. The instrument monitored five selected frequencies continuously. The data were recorded on

198-401: Is caused by variations in the jet stream and other local wind shears, although areas of significant convective activity ( thunderstorms ) in the troposphere below may produce turbulence as a result of convective overshoot . On October 24, 2014, Alan Eustace became the record holder for reaching the altitude record for a manned balloon at 135,890 ft (41,419 m). Eustace also broke

231-521: Is due to the reaction of hydroxyl radicals (•OH) with ozone. •OH is formed by the reaction of electrically excited oxygen atoms produced by ozone photolysis, with water vapor. While the stratosphere is dry, additional water vapor is produced in situ by the photochemical oxidation of methane (CH 4 ). The HO 2 radical produced by the reaction of OH with O 3 is recycled to OH by reaction with oxygen atoms or ozone. In addition, solar proton events can significantly affect ozone levels via radiolysis with

264-487: Is the breaking planetary waves resulting in intense quasi-horizontal mixing in the midlatitudes. This breaking is much more pronounced in the winter hemisphere where this region is called the surf zone. This breaking is caused due to a highly non-linear interaction between the vertically propagating planetary waves and the isolated high potential vorticity region known as the polar vortex . The resultant breaking causes large-scale mixing of air and other trace gases throughout

297-466: 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

330-550: Is therefore important for the survival of the Cape Royds penguin colony. 75°S 45°W  /  75°S 45°W  / -75; -45 This Antarctica -related article is a stub . You can help Misplaced Pages by expanding it . This oceanography article is a stub . You can help Misplaced Pages by expanding it . This glaciology article is a stub . You can help Misplaced Pages by expanding it . Nimbus 5 Nimbus 5 (also called Nimbus E or Nimbus V )

363-494: The Earth once every 107 minutes, at an inclination of 99°. Its perigee was 1,089 kilometers (677 mi) and its apogee was 1,101 kilometers (684 mi). There were six science instruments aboard Nimbus 5. The satellite also included Sun sensors , and horizon scanners for navigation. The ITPR was designed to obtain vertical profiles of temperature and moisture in the atmosphere. A 3-dimensional map could then be created with

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396-458: 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 ,

429-604: The UV-C region, at wavelengths shorter than about 240 nm. Radicals produced from the homolytically split oxygen molecules combine with molecular oxygen to form ozone. Ozone in turn is photolysed much more rapidly than molecular oxygen as it has a stronger absorption that occurs at longer wavelengths, where the solar emission is more intense. Ozone (O 3 ) photolysis produces O and O 2 . The oxygen atom product combines with atmospheric molecular oxygen to reform O 3 , releasing heat. The rapid photolysis and reformation of ozone heat

462-550: The 1970s, the polar Southern Ocean south of the Antarctic Circumpolar Current has freshened and stratified, likely a result of anthropogenic climate change . Such stratification may be responsible for suppressing the return of the Weddell Sea polynya. More recently, it was found that intense cyclones occurring over the ice pack, far south from the ice edge, were at the origin of the reoccurrence of

495-894: The Weddell or Maud Rise Polynya in austral winter 2017. In certain winter months, the general atmospheric circulation around Antarctica exhibits a strong zonal wave 3 pattern, which favors the development of polar cyclones closer to the coast, that is, over preconditioned oceanographic areas for polynya formation, such as the Weddell Polynya in the Lazarev Sea and the Cosmonaut polynya in the Cosmonaut Sea around Antarctica. The presence of polynyas in McMurdo Sound provides an ice-free area where penguins can feed, and

528-402: The altitudes of normal lightning and storm clouds. Upper-atmospheric lightning is believed to be electrically induced forms of luminous plasma . Lightning extending above the troposphere into the stratosphere is referred to as blue jet , and that reaching into the mesosphere as red sprite . Bacterial life survives in the stratosphere, making it a part of the biosphere . In 2001, dust

561-489: The cold European winters of the 1960s. Stratospheric warming of the polar vortex results in its weakening. When the vortex is strong, it keeps the cold, high-pressure air masses contained in the Arctic ; when the vortex weakens, air masses move equatorward, and results in rapid changes of weather in the mid latitudes. Upper-atmospheric lightning is a family of short-lived electrical-breakdown phenomena that occur well above

594-533: The discovery of an isothermal layer at around 11–14 km (6.8-8.7 mi), which is the base of the lower stratosphere. This was based on temperature profiles from mostly unmanned and a few manned instrumented balloons. The mechanism describing the formation of the ozone layer was described by British mathematician and geophysicist Sydney Chapman in 1930, and is known as the Chapman cycle or ozone–oxygen cycle . Molecular oxygen absorbs high energy sunlight in

627-566: The lift by the lift-to-drag ratio .) It also allows the airplane to stay above the turbulent weather of the troposphere. The Concorde aircraft cruised at Mach 2 at about 60,000 ft (18 km), and the SR-71 cruised at Mach 3 at 85,000 ft (26 km), all within the stratosphere. Because the temperature in the tropopause and lower stratosphere is largely constant with increasing altitude, very little convection and its resultant turbulence occurs there. Most turbulence at this altitude

660-440: The lower edge of the stratosphere is as high as 20 km (66,000 ft; 12 mi), at mid-latitudes around 10 km (33,000 ft; 6.2 mi), and at the poles about 7 km (23,000 ft; 4.3 mi). Temperatures range from an average of −51 °C (−60 °F; 220 K) near the tropopause to an average of −15 °C (5.0 °F; 260 K) near the mesosphere. Stratospheric temperatures also vary within

693-406: The lower reaches of the stratosphere in temperate latitudes. This optimizes fuel efficiency , mostly due to the low temperatures encountered near the tropopause and low air density, reducing parasitic drag on the airframe . Stated another way, it allows the airliner to fly faster while maintaining lift equal to the weight of the plane. (The fuel consumption depends on the drag, which is related to

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726-492: The midlatitude surf zone. The timescale of this rapid mixing is much smaller than the much slower timescales of upwelling in the tropics and downwelling in the extratropics. During northern hemispheric winters, sudden stratospheric warmings , caused by the absorption of Rossby waves in the stratosphere, can be observed in approximately half of winters when easterly winds develop in the stratosphere. These events often precede unusual winter weather and may even be responsible for

759-438: The ozone layer allows life to exist on the surface of the planet outside of the ocean. All air entering the stratosphere must pass through the tropopause , the temperature minimum that divides the troposphere and stratosphere. The rising air is literally freeze dried; the stratosphere is a very dry place. The top of the stratosphere is called the stratopause , above which the temperature decreases with height. Sydney Chapman gave

792-499: The stratosphere as the seasons change, reaching particularly low temperatures in the polar night (winter). Winds in the stratosphere can far exceed those in the troposphere, reaching near 60 m/s (220 km/h; 130 mph) in the Southern polar vortex . In 1902, Léon Teisserenc de Bort from France and Richard Assmann from Germany, in separate but coordinated publications and following years of observations, published

825-432: The stratosphere dynamically stable: there is no regular convection and associated turbulence in this part of the atmosphere. However, exceptionally energetic convection processes, such as volcanic eruption columns and overshooting tops in severe supercell thunderstorms , may carry convection into the stratosphere on a very local and temporary basis. Overall, the attenuation of solar UV at wavelengths that damage DNA by

858-432: The stratosphere is termed as Brewer-Dobson circulation , which is a single-celled circulation, spanning from the tropics up to the poles, consisting of the tropical upwelling of air from the tropical troposphere and the extra-tropical downwelling of air. Stratospheric circulation is a predominantly wave-driven circulation in that the tropical upwelling is induced by the wave force by the westward propagating Rossby waves , in

891-470: The stratosphere, resulting in a temperature inversion. This increase of temperature with altitude is characteristic of the stratosphere; its resistance to vertical mixing means that it is stratified. Within the stratosphere temperatures increase with altitude (see temperature inversion ) ; the top of the stratosphere has a temperature of about 270 K (−3 °C or 26.6 °F ). This vertical stratification , with warmer layers above and cooler layers below, makes

924-424: The subsequent formation of OH. Nitrous oxide (N 2 O) is produced by biological activity at the surface and is oxidised to NO in the stratosphere; the so-called NO x radical cycles also deplete stratospheric ozone. Finally, chlorofluorocarbon molecules are photolysed in the stratosphere releasing chlorine atoms that react with ozone giving ClO and O 2 . The chlorine atoms are recycled when ClO reacts with O in

957-573: The upper stratosphere, or when ClO reacts with itself in the chemistry of the Antarctic ozone hole. Paul J. Crutzen, Mario J. Molina and F. Sherwood Rowland were awarded the Nobel Prize in Chemistry in 1995 for their work describing the formation and decomposition of stratospheric ozone. Commercial airliners typically cruise at altitudes of 9–12 km (30,000–39,000 ft) which is in

990-456: The world records for vertical speed skydiving, reached with a peak velocity of 1,321 km/h (822 mph) and total freefall distance of 123,414 ft (37,617 m) – lasting four minutes and 27 seconds. The stratosphere is a region of intense interactions among radiative, dynamical , and chemical processes, in which the horizontal mixing of gaseous components proceeds much more rapidly than does vertical mixing. The overall circulation of

1023-441: Was a meteorological satellite for the research and development of sensing technology. It was the fifth successful launch in a series of the Nimbus program . The objective of Nimbus 5 was to test and evaluate advanced sensing technology, and to provide improved photographs of cloud formations. Nimbus 5 was launched on December 11, 1972, by a Delta rocket from Vandenberg Air Force Base , California , USA. The satellite orbited

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1056-550: Was collected at a height of 41 kilometres in a high-altitude balloon experiment and was found to contain bacterial material when examined later in the laboratory. Some bird species have been reported to fly at the upper levels of the troposphere. On November 29, 1973, a Rüppell's vulture ( Gyps rueppelli ) was ingested into a jet engine 11,278 m (37,000 ft) above the Ivory Coast . Bar-headed geese ( Anser indicus ) sometimes migrate over Mount Everest , whose summit

1089-425: Was used for measuring cloud top temperatures and water vapor content in the stratosphere . It could measure cloud temperatures in the day and at night. The sensing unit was a bolometer made from germanium . This spacecraft or satellite related article is a stub . You can help Misplaced Pages by expanding it . Stratosphere The stratosphere ( / ˈ s t r æ t ə ˌ s f ɪər , - t oʊ -/ )

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