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Advanced Technology Microwave Sounder
The Advanced Technology Microwave Sounder (ATMS) is a 22-channel scanning microwave radiometer for observation of the Earth's atmosphere and surface. It is the successor to the Advanced Microwave Sounding Unit (AMSU) on NOAA weather satellites. ATMS units have been flown on the Suomi NPP and on the Joint Polar Satellite System. Applications ATMS measurements are assimilated into numerical weather prediction models and atmospheric profiles retrieved by the combination of ATMS and the Cross-track Infrared Sounder on the same satellites are useful for synoptic scale meteorology. Also, ATMS continues the record from its predecessor instruments MSU and AMSU of measurements in the 5-mm band of oxygen for monitoring of atmospheric temperature trends. Instrument characteristics All of the channels are contained within one unit, unlike the AMSU which comprises two instruments (AMSU-A and AMSU-B). The radiometer's antenna scans underneath the satellite through nadir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NOAA
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditions, charts the seas, conducts deep sea exploration, and manages fishing and protection of marine mammals and endangered species in the U.S. exclusive economic zone. Purpose and function NOAA's specific roles include: * ''Supplying Environmental Information Products''. NOAA supplies to its customers and partners information pertaining to the state of the oceans and the atmosphere, such as weather warnings and forecasts via the National Weather Service. NOAA's information services extend as well to climate, ecosystems, and commerce. * ''Providing Environmental Stewardship Services''. NOAA is a steward of U.S. coastal and marine environments. In coordination with federal, state, local, tribal and international authorities, NOAA manages the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suomi NPP
The Suomi National Polar-orbiting Partnership (Suomi NPP), previously known as the National Polar-orbiting Operational Environmental Satellite System Preparatory Project (NPP) and NPP-Bridge, is a weather satellite operated by the United States National Oceanic and Atmospheric Administration (NOAA). It was launched in 2011 and continues to operate in June 2022. Suomi NPP was originally intended as a pathfinder for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) program, which was to have replaced NOAA's Polar Operational Environmental Satellites (POES) and the U.S. Air Force's Defense Meteorological Satellite Program (DMSP). Suomi NPP was launched in 2011 after the cancellation of NPOESS to serve as a stop-gap between the POES satellites and the Joint Polar Satellite System (JPSS) which will replace them. Its instruments provide climate measurements that continue prior observations by NASA's Earth Observing System (EOS). Name The satellite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joint Polar Satellite System
The Joint Polar Satellite System (JPSS) is the latest generation of U.S. polar-orbiting, non-geosynchronous, environmental satellites. JPSS will provide the global environmental data used in numerical weather prediction models for forecasts, and scientific data used for climate monitoring. JPSS will aid in fulfilling the mission of the U.S. National Oceanic and Atmospheric Administration (NOAA), an agency of the Department of Commerce. Data and imagery obtained from the JPSS will increase timeliness and accuracy of public warnings and forecasts of climate and weather events, thus reducing the potential loss of human life and property and advancing the national economy. The JPSS is developed by the National Aeronautics and Space Administration (NASA) for the National Oceanic and Atmospheric Administration (NOAA), who is responsible for operation of JPSS. Three to five satellites are planned for the JPSS constellation of satellites. JPSS satellites will be flown, and the scientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Numerical Weather Prediction
Numerical weather prediction (NWP) uses mathematical models of the atmosphere and oceans to predict the weather based on current weather conditions. Though first attempted in the 1920s, it was not until the advent of computer simulation in the 1950s that numerical weather predictions produced realistic results. A number of global and regional forecast models are run in different countries worldwide, using current weather observations relayed from radiosondes, weather satellites and other observing systems as inputs. Mathematical models based on the same physical principles can be used to generate either short-term weather forecasts or longer-term climate predictions; the latter are widely applied for understanding and projecting climate change. The improvements made to regional models have allowed for significant improvements in Tropical cyclone track forecasting, tropical cyclone track and air quality forecasts; however, atmospheric models perform poorly at handling process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmospheric Sounding
Atmospheric sounding or atmospheric profiling is a measurement of vertical distribution of physical properties of the atmospheric column such as 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 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 AIRS and AMSU * observation of atmospheres on different planets, such as the Mars climate sounder on the Mars Reconnaissance Orbiter Direct methods Sensors that measure atmospheric constituents directly, such as thermometers, barometers, and humidity sensors, can be sent aloft on balloons, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synoptic Scale Meteorology
The synoptic scale in meteorology (also known as large scale or cyclonic scale) is a horizontal length scale of the order of 1000 kilometers (about 620 miles) or more. This corresponds to a horizontal scale typical of mid-latitude depressions (e.g., extratropical cyclones). Most high- and low-pressure areas seen on weather maps (such as surface weather analyses) are synoptic-scale systems, driven by the location of Rossby waves in their respective hemisphere. Low-pressure areas and their related frontal zones occur on the leading edge of a trough within the Rossby wave pattern, while high-pressure areas form on the back edge of the trough. Most precipitation areas occur near frontal zones. The word ''synoptic'' is derived from the Greek word ('), meaning ''seen together''. The Navier–Stokes equations applied to atmospheric motion can be simplified by scale analysis in the synoptic scale. It can be shown that the main terms in horizontal equations are Coriolis force and p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microwave Sounding Unit
The microwave sounding unit (MSU) was the predecessor to the Advanced Microwave Sounding Unit (AMSU). The MSU was first launched aboard the TIROS-N satellite in late 1978 and provided global coverage (from Pole to Pole). It carries a 4-channel microwave radiometer, operating between 50 and 60 Hertz, GHz. Spatial resolution on the ground was 2.5 deg in longitude and latitude (about 250 km circle). There were 9 different MSUs launched; the most recent one on NOAA-14. They provided measurements of the temperature of the troposphere and lower stratosphere until 1998, when the first AMSU was deployed. AMSU provides many more channels and finer resolution (about 50 km). Table 1 lists some characteristics of the MSU. The radiometer's antenna scans underneath the satellite through nadir, and its polarization vector rotates with the scan angle. In the table, "vertical polarization near nadir" means that the E-vector is parallel to the scan direction at nadir, and "horizon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nadir
The nadir (, ; ar, نظير, naẓīr, counterpart) 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. Definitions Space science Since the concept of ''being below'' is itself somewhat vague, scientists define the nadir in more rigorous terms. Specifically, in astronomy, geophysics and related sciences (e.g., meteorology), the nadir at a given point is the local vertical direction pointing in the direction of the force of gravity at that location. The term can also be used to represent the lowest point that a celestial object reaches along its apparent daily path around a given point of observation (i.e. the object's ''lower culmination''). This can be used to describe the position of the Sun, but it is only technically accurate for one latitude at a time and only possible at the low latitudes. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nyquist–Shannon Sampling Theorem
The Nyquist–Shannon sampling theorem is a theorem in the field of signal processing which serves as a fundamental bridge between continuous-time signals and discrete-time signals. It establishes a sufficient condition for a sample rate that permits a discrete sequence of ''samples'' to capture all the information from a continuous-time signal of finite bandwidth. Strictly speaking, the theorem only applies to a class of mathematical functions having a Fourier transform that is zero outside of a finite region of frequencies. Intuitively we expect that when one reduces a continuous function to a discrete sequence and interpolates back to a continuous function, the fidelity of the result depends on the density (or sample rate) of the original samples. The sampling theorem introduces the concept of a sample rate that is sufficient for perfect fidelity for the class of functions that are band-limited to a given bandwidth, such that no actual information is lost in the sampling proc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noise-equivalent Temperature
Noise-equivalent temperature (NET) is a measure of the sensitivity of a detector of thermal radiation in the infrared, terahertz or microwave portions of the electromagnetic spectrum. It is the amount of incident signal temperature that would be needed to match the internal noise of the detector such that the signal-to-noise ratio is equal to one. Often the spectrum of the NET is reported as a temperature ''per root bandwidth''. A detector that measures power is often interested in the analogous noise-equivalent power (NEP). If a relation between intensity and temperature is well defined over the passband, as in the case of a blackbody, then the NET simply scales with the NEP. If a detector is limited by either shot noise or Johnson noise then the NET can be decreased by using an increased integration time. The NET of flicker noise limited detectors can not be reduced by increased integration time. Typically uncooled bolometric detectors have NET figures of 30-200 mK. Cooled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
