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Bergen School Of Meteorology
__NOTOC__ The "Bergen School of Meteorology" is a school of thought which is the basis for much of modern weather forecasting. Founded by the meteorologist Prof. Vilhelm Bjerknes and his younger colleagues in 1917, the Bergen School attempts to define the motion of the atmosphere by means of the mathematics of interactions between hydro- and thermodynamics, some of which had originally been discovered or explained by Bjerknes himself, thus making mathematical predictions regarding the weather possible by systematic data analysis. Much of the work was done at the Geophysical Institute, University of Bergen, in Bergen, Norway. The Bergen School was crucial in the early development and operationalization of numerical weather forecasting in the 1940s and 1950s, which was largely a cooperation between Scandinavian and US researchers. In this development, extant meteorological theories were synthesized. Due to the vast amount of calculations necessary for producing viable forecasts, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather Forecasting
Weather forecasting is the application of science and technology forecasting, to predict the conditions of the Earth's atmosphere, atmosphere for a given location and time. People have attempted to predict the weather informally for millennia and formally since the 19th century. Weather forecasts are made by collecting quantitative data about the current state of the atmosphere, land, and ocean and using meteorology to project how the atmosphere will change at a given place. Once calculated manually based mainly upon changes in atmospheric pressure, barometric pressure, current weather conditions, and sky condition or cloud cover, weather forecasting now relies on numerical weather prediction, computer-based models that take many atmospheric factors into account. Human input is still required to pick the best possible forecast model to base the forecast upon, which involves pattern recognition skills, teleconnections, knowledge of model performance, and knowledge of model biases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl-Gustaf Rossby
Carl-Gustaf Arvid Rossby ( 28 December 1898 – 19 August 1957) was a Swedish-born American meteorologist who first explained the large-scale motions of the atmosphere in terms of fluid mechanics. He identified and characterized both the jet stream and the long waves in the westerlies that were later named Rossby waves. Biography Carl-Gustaf Rossby was born in Stockholm, Sweden. He was the first of five children born to Arvid and Alma Charlotta (Marelius) Rossby. He attended Stockholm University, where he developed his first interest in mathematical physics. Rossby came into meteorology and oceanography while studying geophysics under Vilhelm Bjerknes at the Geophysical Institute, University of Bergen in Bergen, Norway, during 1919, where Bjerknes' group was developing the groundbreaking concepts that became known as the Bergen School of Meteorology, including theory of the polar front. He also studied at the University of Leipzig and at the Lindenberg Observatory (''Meteoro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arnt Eliassen
Arnt Eliassen (9 September 1915 – 22 April 2000) was a Norwegian meteorologist who was a pioneer in the use of numerical analysis and computers for weather forecasting. Career The early pioneer work was done at the Institute for Advanced Study in Princeton, New Jersey, together with John von Neumann. His areas of research included free and thermally driven circulations, frontogenesis, and shear and gravitational–acoustic wave propagation in stratified media. Eliassen received the Carl-Gustaf Rossby Research Medal in 1964 for his many important contributions to dynamical meteorology. He received the Balzan Prize in 1996 "For his fundamental contributions to dynamic meteorology that have influenced and stimulated progress in this science during the past fifty years". Two years later, he was awarded the Vilhelm Bjerknes Medal for "his outstanding fundamental contributions to dynamical meteorology". Personal Eliassen was a brother of architect Trond Eliassen. He is the fa ... [...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] |
Surface Weather Analysis
Surface weather analysis is a special type of weather map that provides a view of weather elements over a geographical area at a specified time based on information from ground-based weather stations. Weather maps are created by plotting or tracing the values of relevant quantities such as sea level pressure, temperature, and cloud cover onto a geographical map to help find synoptic scale features such as weather fronts. The first weather maps in the 19th century were drawn well after the fact to help devise a theory on storm systems.Eric R. MillerAmerican Pioneers in Meteorology.Retrieved on 2007-04-18. After the advent of the telegraph, simultaneous surface weather observations became possible for the first time, and beginning in the late 1840s, the Smithsonian Institution became the first organization to draw real-time surface analyses. Use of surface analyses began first in the United States, spreading worldwide during the 1870s. Use of the Norwegian cyclone model for fronta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclogenesis
Cyclogenesis is the development or strengthening of cyclonic circulation in the atmosphere (a low-pressure area). Cyclogenesis is an umbrella term for at least three different processes, all of which result in the development of some sort of cyclone, and at any size from the microscale to the synoptic scale. * Tropical cyclones form due to latent heat driven by significant thunderstorm activity, developing a warm core. * Extratropical cyclones form as waves along weather fronts before occluding later in their life cycle as cold core cyclones. * Mesocyclones form as warm core cyclones over land, and can lead to tornado formation. Waterspouts can also form from mesocyclones, but more often develop from environments of high instability and low vertical wind shear. The process in which an extratropical cyclone undergoes a rapid drop in atmospheric pressure (24 millibars or more) in a 24-hour period is referred to as explosive cyclogenesis, and is usually present during the formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norwegian Cyclone Model
The older of the models of extratropical cyclone development is known as the Norwegian cyclone model, developed during and shortly after World War I within the Bergen School of Meteorology. In this theory, cyclones develop as they move up and along a frontal boundary, eventually occluding and reaching a barotropically cold environment.Shaye JohnsonThe Norwegian Cyclone Model. Retrieved on 2006-10-11. It was developed completely from surface-based weather observations, including descriptions of clouds found near frontal boundaries. Developed from this model was the concept of the warm conveyor belt, which transports warm and moist air just ahead of the cold front above the surface warm front. Development of the theory Polar front theory is attributed to Jacob Bjerknes, derived from a coastal network of observation sites in Norway during World War I. This theory proposed that the main inflow into a cyclone was concentrated along two lines of convergence, one ahead of the low and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johan Sandström
Johan Wilhelm Sandström (6 June 1874, Degerfors, Västerbotten County – 12 January 1947, Bromma, Stockholm County), usually cited as J. W. Sandström, was a Swedish oceanographer and meteorologist. He is most famously known for conducting a series of classical experiments at Bornö Marine Research Station in Sweden published in 1908. His experiments concerned themselves with the causes of ocean currents, particularly those found in fjords. Biography Sandström is the son of carpenter Jonas Anton Sandström and Greta Magdalena Sjögren. He went to Degerfors Elementary School but upon the death of his father, his mother moved the family to Sundsvall, where Sandström worked in a sawmill while being tutored. Thanks to local benefactors, he entered a Stockholm technical school, and although he never received an official diploma, he excelled in mathematics and frequented scientific circles. In 1899, Sandström joined the national meteorological service where he met Vilhelm Bje ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Ludvig Godske
Carl Ludvig Schreiner Godske (20 May 1906 – 3 July 1970) was a Norwegian mathematician and meteorologist. He was born in Bindal. He was a member of the Bergen School of Meteorology, working as meteorologist in Bergen from 1938, and appointed professor at the University of Bergen from 1946. Among his publications is ''Dynamic Meteorology and Weather Forecasting'' from 1957. He was also a pioneer in the application of electronic computers in Norway. He chaired the Norwegian Geophysical Society from 1956 to 1957 and was a fellow of the Norwegian Academy of Science and Letters The Norwegian Academy of Science and Letters ( no, Det Norske Videnskaps-Akademi, DNVA) is a learned society based in Oslo, Norway. Its purpose is to support the advancement of science and scholarship in Norway. History The Royal Frederick Unive ... from 1937. He was decorated Knight, First Class of the Order of St. Olav in 1967. References 1906 births 1970 deaths People from Bindal Norwegia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Svein Rosseland
Svein Rosseland (March 31, 1894, in Kvam, Hardanger – January 19, 1985, in Bærum) was a Norwegian astrophysicist and a pioneer in the field of theoretical astrophysics. Biography Svein Rosseland was born in Kvam, in Hardanger, Norway. Rosseland grew up the youngest of nine siblings. He went to his final exams in Haugesund in 1917 and then went to the University of Oslo. After only three semesters at the University he left in 1919 to work as an assistant professor with the meteorologist Vilhelm Bjerknes at the Bergen School of Meteorology. In 1920 he went to the Institute of Physics (now the Niels Bohr Institute) in Copenhagen, where he met Niels Bohr and other prominent physicists, and where he wrote two seminal papers. He spent 1924–1926 as a Rockefeller Fellow at the Mount Wilson Observatory in Pasadena, California. In 1927, Rosseland earned a PhD. from the University of Oslo. As a professor at the University of Oslo from 1928 to 1964, he built up and headed academics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erik Björkdal
Erik Anton Björkdal was a Swedish meteorologist who studied at the Bergen School of Meteorology where the theory of fronts was developed. His contribution was mainly in the field of dynamic meteorology. Among his works, mention must be made of the correlation between the tropopause geopotential and the troposphere temperature. Biography Björkdal was born on 21 February 1899 in Vimmerby, Sweden.. After high school, he was admitted to the University of Uppsala and graduated in 1920. However, in 1919 he was employed by Vilhelm Bjerknes as an assistant at the Bergen School of Meteorology. After graduation, he was transferred to the Norwegian Meteorological Institute in Oslo where he became Division Chief in 1937. During the Second World War, he replaced the director of the institute, Dr. Th. Hesselberg, who was absent for a period of time because of health problems. He eventually became head of meteorology at the Swedish Meteorological and Hydrological Institute in Stockholm in 1949 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
