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Atmospheric Profiling
Atmospheric sounding or atmospheric profiling is a measurement of vertical distribution of physical properties of the atmosphere, atmospheric column such as atmospheric pressure, pressure, temperature, wind speed and wind direction (thus deriving wind shear), liquid water content, ozone concentration, pollution, and other properties. Such measurements are performed in a variety of ways including remote sensing and in situ#Earth and atmospheric sciences, in situ observations. The most common in situ sounding is a radiosonde, which usually is a weather balloon, but can also be a rocketsonde. Remote sensing soundings generally use passive infrared and microwave radiometers: * airborne instruments * surface stations * Earth-observing satellite instruments such as Atmospheric Infrared Sounder, AIRS and Advanced Microwave Sounding Unit, AMSU * observation of atmospheres on different planets, such as the Mars climate sounder on the Mars Reconnaissance Orbiter Direct methods Sensors that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertical Distribution
Vertical position or vertical location is a position (mathematics), position along a vertical direction (the plumb line direction) above or below a given vertical datum (a reference level surface, such as mean sea level). Vertical distance or vertical separation is the distance between two vertical positions. Many vertical coordinates exist for expressing vertical position: depth, height, altitude, elevation, etc. Points lying on an equigeopotential surface are said to be on the same vertical level, as in a water level (device), water level. A function (mathematics), function with domain (mathematics), domain along the vertical line is called a ''vertical distribution'' or ''vertical profile''. Definitions The International Organization for Standardization (ISO), more specifically Spatial reference system, ISO 19111, offers the following two definitions: * ''depth'': "distance of a point from a chosen reference surface measured downward along a line perpendicular to that surface." ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Climate Sounder
The ''Mars Reconnaissance Orbiter'' (''MRO'') is a spacecraft designed to search for the existence of water on Mars and provide support for missions to Mars, as part of NASA's Mars Exploration Program. It was launched from Cape Canaveral on August 12, 2005, at 11:43 UTC and reached Mars on March 10, 2006, at 21:24 UTC. In November 2006, after six months of aerobraking, it entered its final science orbit and began its primary science phase. Mission objectives include observing the climate of Mars, investigating geologic forces, providing reconnaissance of future landing sites, and relaying data from surface missions back to Earth. To support these objectives, the ''MRO'' carries different scientific instruments, including three cameras, two spectrometers and a subsurface radar. As of July 29, 2023, the ''MRO'' has returned over 450 terabits of data, helped choose safe landing sites for NASA's Mars landers, discovered pure water ice in new craters and further evidence that wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SCIAMACHY
SCIAMACHY (SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY; Greek: σκιαμαχεί: analogously: "Fighting shadows") was one of ten instruments aboard of ESA's ENVIronmental SATellite, ENVISAT. It was a satellite spectrometer designed to measure sunlight, transmitted, reflected and scattered by the Earth's atmosphere or surface in the ultraviolet, visible and near infrared wavelength region (240 nm - 2380 nm) at moderate spectral resolution (0.2 nm - 1.5 nm). SCIAMACHY was built by Netherlands and Germany at TNO/TPD, SRON and Dutch Space. Launch and termination SCIAMACHY, aboard the ENVISAT satellite, was launched by ESA (European Space Agency) from Kourou, French Guiana, in March 2002. ENVISAT's mission was ended in May 2012, after loss of contact one month earlier. Operation The absorption, reflection and scattering characteristics of the atmosphere were determined by measuring the extraterrestrial solar irradiance and the upwe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nadir
The nadir is the direction pointing directly ''below'' a particular location; that is, it is one of two vertical directions at a specified location, orthogonal to a horizontal flat surface. The direction opposite of the nadir is the zenith. Etymology Although it entered English via other European languages, the word “nadir” is ultimately an Arabic loanword. It comes from the Arabic word “nazir”, meaning “opposite to”. More specifically, it originated from the Arabic phrase “nazir as-samt”, meaning “ heopposite direction”. Hebrew (whether ancient or modern) is a related language to Arabic, as they are both Semitic languages. Hebrew also has a word “nadir” (נדיר), but with a somewhat different meaning: it is an adjective meaning “rare”. However, the same word also has a specialized usage to match its meaning in other languages like English. Definitions Space science Since the concept of ''being below'' is itself somewhat vague, scientists define ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occultation
An occultation is an event that occurs when one object is hidden from the observer by another object that passes between them. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks from view (occults) an object in the background. In this general sense, occultation applies to the visual scene observed from low-flying aircraft (or computer-generated imagery) when foreground objects obscure distant objects dynamically, as the scene changes over time. If the closer body does not entirely conceal the farther one, the event is called a '' transit''. Both transit and occultation may be referred to generally as ''occlusion''; and if a shadow is cast onto the observer, it is called an eclipse. The symbol for an occultation, and especially a solar eclipse, is 🝵 (U+1F775 🝵). Occultations by the Moon The term occultation is most frequently used to describe lunar occultations, those relatively frequent occasions wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EUMETSAT
The European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) is an intergovernmental organisation created through an international convention agreed by a current total of 30 European Member States. EUMETSAT's primary objective is to establish, maintain and exploit European systems of operational meteorological satellites. EUMETSAT is responsible for the launch and operation of the satellites and for delivering satellite data to end-users as well as contributing to the operational monitoring of climate and the detection of global climate changes. The activities of EUMETSAT contribute to a global meteorological satellite observing system coordinated with other space-faring states. Satellite observations are an essential input to numerical weather prediction systems and also assist the human forecaster in the diagnosis of potentially hazardous weather developments. Of growing importance is the capacity of weather satellites to gather long-term measure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NOAA
The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with forecasting weather, monitoring oceanic and atmospheric conditions, charting the seas, conducting deep-sea exploration, and managing fishing and protection of marine mammals and endangered species in the US exclusive economic zone. The agency is part of the United States Department of Commerce and is headquartered in Silver Spring, Maryland. History NOAA traces its history back to multiple agencies, some of which are among the earliest in the federal government: * United States Coast and Geodetic Survey, formed in 1807 * Weather Bureau of the United States, formed in 1870 * Bureau of Commercial Fisheries, formed in 1871 (research fleet only) * Coast and Geodetic Survey Corps, formed in 1917 The most direct predecessor of NOAA was the Environmental Science Services Administration (ESSA), into which several existing scientific agencies such as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodar
Sodar, an acronym of sonic detection and ranging, is a meteorological instrument used as a wind profiler based on the Wave scattering, scattering of sound waves by atmospheric turbulence. Sodar equipment is used to measure wind speed at various heights above the ground, and the thermodynamic structure of the lower layer of the atmosphere. Sodar systems are in fact nothing more than sonar systems used in the air rather than in water. More specifically, since they operate using the Doppler effect with a multi-beam configuration to determine wind speed, they are the exact in-air equivalent to a subclass of sonar systems known as ''acoustic Doppler current profilers'' (ADCP). Other names used for sodar systems include sounder, echosounder and acoustic radar. Doppler sodar Commercial sodars operated to collect upper-air wind measurements consist of antennas that transmit and receive acoustics, acoustic signals. A mono-static system uses the same antenna for transmitting and receivi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceilometer
A ceilometer is a device that uses a laser or other light source to determine the height of a cloud ceiling or cloud base. Ceilometers can also be used to measure the aerosol concentration within the atmosphere. A ceilometer that uses laser light is a type of atmospheric lidar (light detection and ranging) instrument. Optical drum ceilometer An optical drum ceilometer uses triangulation to determine the height of a spot of light projected onto the base of the cloud. It consists essentially of a rotating projector, a detector, and a recorder. The projector emits an intense beam of light above into the sky at an angle that varies with the rotation. The detector, which is located at a fixed distance from the projector, uses a photodetector pointing vertically. When it detects the projected light return from the cloud base, the instrument notes the angle and the calculation gives the height of clouds. Laser ceilometer A laser ceilometer consists of a vertically pointing laser and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lidar
Lidar (, also LIDAR, an acronym of "light detection and ranging" or "laser imaging, detection, and ranging") is a method for determining ranging, ranges by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. Lidar may operate in a fixed direction (e.g., vertical) or it may scan multiple directions, in a special combination of 3-D scanning and laser scanning. Lidar has terrestrial, airborne, and mobile applications. It is commonly used to make high-resolution maps, with applications in surveying, geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, atmospheric physics, laser guidance, airborne laser swathe mapping (ALSM), and Mars Orbiter Laser Altimeter, laser altimetry. It is used to make digital 3D modeling, 3-D representations of areas on the Earth's surface and ocean bottom of the intertidal and near coastal zone by varying the wavelength of light. It has also been in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain. The term ''RADAR'' was coined in 1940 by the United States Navy as an acronym for "radio detection and ranging". The term ''radar'' has since entered English and other languages as an anacronym, a common noun, losing all capitalization. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiometers
A radiometer or roentgenometer is a device for measuring the radiant flux (power) of electromagnetic radiation. Generally, a radiometer is an infrared radiation detector or an ultraviolet detector. Microwave radiometers operate in the microwave wavelengths. While the term ''radiometer'' can refer to any device that measures electromagnetic radiation (e.g. light), the term is often used to refer specifically to a Crookes radiometer ("light-mill"), a device invented in 1873 in which a rotor (having vanes which are dark on one side, and light on the other) in a partial vacuum spins when exposed to light. A common misbelief (one originally held even by Crookes) is that the momentum of the absorbed light on the black faces makes the radiometer operate. If this were true, however, the radiometer would spin away from the non-black faces, since the photons bouncing off those faces impart more momentum than the photons absorbed on the black faces. Photons do exert radiation pressure on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
