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Global Forecast System
The Global Forecast System (GFS) is a global numerical weather prediction system containing a global computer model and variational analysis run by the United States' National Weather Service (NWS). Operation The mathematical model is run four times a day, and produces forecasts for up to 16 days in advance, but with decreased spatial resolution after 10 days. The forecast skill generally decreases with time (as with any numerical weather prediction model) and for longer term forecasts, only the larger scales retain significant accuracy. It is one of the predominant synoptic scale medium-range models in general use. Principles The GFS model is a FV3 model with an approximate horizontal resolution of 13 km for the days 0-16 days. In the vertical, the model is divided into 127 layers and extends to the mesopause (roughly ~80 km), and temporally, it produces forecast output every hour for the first 120 hours, three hourly through day 10 and 12 hourly through day 16. The outp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GFS 850 MB
GFS may refer to: Computing * GFS2 (Global File System 2), in Linux * Global Forecast System, US weather prediction system * Google File System Education * Garrison Forest School, in Owing Mills, Maryland, US * Germantown Friends School, in Philadelphia, Pennsylvania, US * Griffith Film School, in Brisbane, Australia Other uses * Genome-based peptide fingerprint scanning * GFS Projects (Geoff's Flying Saucer), a British aerospace company * Girls' Friendly Society * GlobalFoundries (Nasdaq: GFS), an American semiconductor manufacturing company * Glucose-fructose syrup, another name for high-fructose corn syrup * Government Flying Service, Hong Kong * Gordon Food Service, North America * Greek Font Society * Grounds For Sculpture, sculpture park and museum located in Hamilton, New Jersey, United States * Groupe Feministe Socialiste, a defunct French feminist group *George Floyd Square, a memorial in Minneapolis, Minnesota, United States See also * GF (other) {{ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Centre For Medium-Range Weather Forecasts
The European Centre for Medium-Range Weather Forecasts (ECMWF) is an independent intergovernmental organisation supported by most of the nations of Europe. It is based at three sites: Shinfield Park, Reading, United Kingdom; Bologna, Italy; and Bonn, Germany. It operates one of the largest supercomputer complexes in Europe and the world's largest archive of numerical weather prediction data. History ECMWF was established in 1975, in recognition of the need to pool the scientific and technical resources of Europe's meteorological services and institutions for the production of weather forecasts for medium-range timescales (up to approximately two weeks) and of the economic and social benefits expected from it. The Centre employs about 350 staff, mostly appointed from across the member states and co-operating states. In 2017, the centre's member states accepted an offer from the Italian Government to move ECMWF's data centre to Bologna, Italy. The new site, a former tobacco f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ensemble Forecasting
Ensemble forecasting is a method used in or within numerical weather prediction. Instead of making a single forecast of the most likely weather, a set (or ensemble) of forecasts is produced. This set of forecasts aims to give an indication of the range of possible future states of the atmosphere. Ensemble forecasting is a form of Monte Carlo method, Monte Carlo analysis. The multiple simulations are conducted to account for the two usual sources of uncertainty in forecast models: (1) the errors introduced by the use of imperfect initial conditions, amplified by the Chaos theory, chaotic nature of the evolution equations of the atmosphere, which is often referred to as sensitive dependence on initial conditions; and (2) errors introduced because of imperfections in the model formulation, such as the approximate mathematical methods to solve the equations. Ideally, the verified future atmospheric state should fall within the predicted ensemble Standard deviation, spread, and the amou ... [...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 and air quality forecasts; however, atmospheric models perform poorly at handling processes that occur in a relatively const ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integrated Forecast System
The Integrated Forecasting System (IFS) is a global numerical weather prediction system jointly developed and maintained by the European Centre for Medium-Range Weather Forecasts (ECMWF) based in Reading, England, and Météo-France based in Toulouse. The version of the IFS run at ECMWF is often referred to as the "ECMWF" or the "European model" in North America, to distinguish it from the American GFS. Mechanism It comprises a spectral atmospheric model with a terrain-following vertical coordinate system coupled to a 4D-Var data assimilation system. In 1997 the IFS became the first operational forecasting system to use 4D-Var. Both ECMWF and Météo-France use the IFS to make operational weather forecasts, but using a different configuration and resolution (the Météo-France configuration is referred to as ARPEGE). It is one of the predominant global medium-range models in general use worldwide; its most prominent rivals in the 6–10 day medium range include the American Glob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unified Forecast System (UFS)
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Unified may refer to: * The Unified, a wine symposium held in Sacramento, California, USA * ''Unified'', the official student newspaper of Canterbury Christ Church University * UNFD, an Australian record label * ''Unified'' (Sweet & Lynch album), 2017 * ''Unified'' (Super8 & Tab album), 2014 Unify may refer to: * ''Unify'', an album by Electric Universe * Unify Corporation, former name of Daegis Inc. * Unify Gathering, an Australian music festival * Unify GmbH & Co. KG, formerly Siemens Enterprise Communications See also * * * * Unification (other) * United (other) * Unity (other) Unity may refer to: Buildings * Unity Building, Oregon, Illinois, US; a historic building * Unity Building (Chicago), Illinois, US; a skyscraper * Unity Buildings, Liverpool, UK; two buildings in England * Unity Chapel, Wyoming, Wisconsin, US; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectral Method
Spectral methods are a class of techniques used in applied mathematics and scientific computing to numerically solve certain differential equations. The idea is to write the solution of the differential equation as a sum of certain " basis functions" (for example, as a Fourier series which is a sum of sinusoids) and then to choose the coefficients in the sum in order to satisfy the differential equation as well as possible. Spectral methods and finite element methods are closely related and built on the same ideas; the main difference between them is that spectral methods use basis functions that are generally nonzero over the whole domain, while finite element methods use basis functions that are nonzero only on small subdomains (compact support). Consequently, spectral methods connect variables ''globally'' while finite elements do so ''locally''. Partially for this reason, spectral methods have excellent error properties, with the so-called "exponential convergence" being the fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Finite Volume Method
The finite volume method (FVM) is a method for representing and evaluating partial differential equations in the form of algebraic equations. In the finite volume method, volume integrals in a partial differential equation that contain a divergence term are converted to surface integrals, using the divergence theorem. These terms are then evaluated as fluxes at the surfaces of each finite volume. Because the flux entering a given volume is identical to that leaving the adjacent volume, these methods are conservative. Another advantage of the finite volume method is that it is easily formulated to allow for unstructured meshes. The method is used in many computational fluid dynamics packages. "Finite volume" refers to the small volume surrounding each node point on a mesh. Finite volume methods can be compared and contrasted with the finite difference methods, which approximate derivatives using nodal values, or finite element methods, which create local approximations of a soluti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geophysical Fluid Dynamics Laboratory
The Geophysical Fluid Dynamics Laboratory (GFDL) is a laboratory in the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR). The current director is Dr. Venkatachalam Ramaswamy. It is one of seven NOAA Research Laboratories (RLs). GFDL is engaged in comprehensive long lead-time research to expand the scientific understanding of the physical processes that govern the behavior of the atmosphere and the oceans as complex fluid systems. These systems can then be modeled mathematically and their phenomenology can be studied by computer simulation methods. GFDL's accomplishments include the development of the first climate models to study global warming, the first comprehensive ocean prediction codes, and the first dynamical models with significant skill in hurricane track and intensity predictions. Much current research within the laboratory is focused around the development of Earth System Models for assessment of natural and hum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Wave Model
In fluid dynamics, wind wave modeling describes the effort to depict the sea state and predict the evolution of the energy of wind waves using numerical techniques. These simulations consider atmospheric wind forcing, nonlinear wave interactions, and frictional dissipation, and they output statistics describing wave heights, periods, and propagation directions for regional seas or global oceans. Such wave hindcasts and wave forecasts are extremely important for commercial interests on the high seas. For example, the shipping industry requires guidance for operational planning and tactical seakeeping purposes. For the specific case of predicting wind wave statistics on the ocean, the term ocean surface wave model is used. Other applications, in particular coastal engineering, have led to the developments of wind wave models specifically designed for coastal applications. Historical overview Early forecasts of the sea state were created manually based upon empirical relation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WAVEWATCH
In fluid dynamics, wind wave modeling describes the effort to depict the sea state and predict the evolution of the energy of wind waves using numerical techniques. These simulations consider atmospheric wind forcing, nonlinear wave interactions, and frictional dissipation, and they output statistics describing wave heights, periods, and propagation directions for regional seas or global oceans. Such wave hindcasts and wave forecasts are extremely important for commercial interests on the high seas. For example, the shipping industry requires guidance for operational planning and tactical seakeeping purposes. For the specific case of predicting wind wave statistics on the ocean, the term ocean surface wave model is used. Other applications, in particular coastal engineering, have led to the developments of wind wave models specifically designed for coastal applications. Historical overview Early forecasts of the sea state were created manually based upon empirical relation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
