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V. Walfrid Ekman
Vagn Walfrid Ekman (3 May 1874 – 9 March 1954) was a Swedish oceanographer. Born in Stockholm to Fredrik Laurentz Ekman, himself an oceanographer, he became committed to oceanography while studying physics at the University of Uppsala and, in particular, on hearing Vilhelm Bjerknes lecture on fluid dynamics. During the expedition of the ''Fram'', Fridtjof Nansen had observed that icebergs tend to drift not in the direction of the prevailing wind but at an angle of 20°-40° to the right. Bjerknes invited Ekman, still a student, to investigate the problem. Later, in 1905, Ekman published his theory of the Ekman spiral which explains the phenomenon in terms of the balance between frictional effects in the ocean and the Coriolis force, which arises from moving objects in a rotating environment, like planetary rotation. On completing his doctorate in Uppsala in 1902, Ekman joined the International Laboratory for Oceanographic Research, Oslo where he worked for seven years, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stockholm
Stockholm () is the Capital city, capital and List of urban areas in Sweden by population, largest city of Sweden as well as the List of urban areas in the Nordic countries, largest urban area in Scandinavia. Approximately 980,000 people live in the Stockholm Municipality, municipality, with 1.6 million in the Stockholm urban area, urban area, and 2.4 million in the Metropolitan Stockholm, metropolitan area. The city stretches across fourteen islands where Mälaren, Lake Mälaren flows into the Baltic Sea. Outside the city to the east, and along the coast, is the island chain of the Stockholm archipelago. The area has been settled since the Stone Age, in the 6th millennium BC, and was founded as a city in 1252 by Swedish statesman Birger Jarl. It is also the county seat of Stockholm County. For several hundred years, Stockholm was the capital of Finland as well (), which then was a part of Sweden. The population of the municipality of Stockholm is expected to reach o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vilhelm Bjerknes
Vilhelm Friman Koren Bjerknes ( , ; 14 March 1862 – 9 April 1951) was a Norwegian physicist and meteorologist who did much to found the modern practice of weather forecasting. He formulated the primitive equations that are still in use in numerical weather prediction and climate modeling, and he developed the so-called Bergen School of Meteorology, which was successful in advancing weather prediction and meteorology in the early 20th century. Life and career Born in Christiania (later renamed Oslo), Bjerknes enjoyed an early exposure to fluid dynamics, as assistant to his father, Carl Anton Bjerknes, who had discovered by mathematical analysis the apparent actions at a distance between pulsating and oscillating bodies in a fluid, and their analogy with the electric and magnetic actions at a distance. Apparently no attempt had been made to demonstrate experimentally the theories arrived at by the older professor until Vilhelm Bjerknes, then about 17 or 18 years of age, tur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscosity
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's axis than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the strength of the compensating force is proportional to the fluid's viscosity. In general, viscosity depends on a fluid's state, such as its temperature, pressure, and rate of deformation. However, the dependence on some of these properties is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind
Wind is the natural movement of air or other gases relative to a planet's surface. Winds occur on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few hours, to global winds resulting from the difference in absorption of solar energy between the climate zones on Earth. The two main causes of large-scale atmospheric circulation are the differential heating between the equator and the poles, and the rotation of the planet (Coriolis effect). Within the tropics and subtropics, thermal low circulations over terrain and high plateaus can drive monsoon circulations. In coastal areas the sea breeze/land breeze cycle can define local winds; in areas that have variable terrain, mountain and valley breezes can prevail. Winds are commonly classified by their spatial scale, their speed and direction, the forces that cause them, the regions in which they occur, and their effect. Winds have various asp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceberg
An iceberg is a piece of freshwater ice more than 15 m long that has broken off a glacier or an ice shelf and is floating freely in open (salt) water. Smaller chunks of floating glacially-derived ice are called "growlers" or "bergy bits". The sinking of the ''Titanic'' in 1912 led to the formation of the International Ice Patrol in 1914. Much of an iceberg is below the surface, which led to the expression "tip of the iceberg" to illustrate a small part of a larger unseen issue. Icebergs are considered a serious maritime hazard. Icebergs vary considerably in size and shape. Icebergs that calve from glaciers in Greenland are often irregularly shaped while Antarctic ice shelves often produce large tabular (table top) icebergs. The largest iceberg in recent history (2000), named B-15, measured nearly 300 km × 40 km. The largest iceberg on record was an Antarctic tabular iceberg of over [] sighted west of Scott Island, in the South Pacific Ocean, by the USS Glacier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fridtjof Nansen
Fridtjof Wedel-Jarlsberg Nansen (; 10 October 186113 May 1930) was a Norwegian polymath and Nobel Peace Prize laureate. He gained prominence at various points in his life as an explorer, scientist, diplomat, and humanitarian. He led the team that made the first crossing of the Greenland interior in 1888, traversing the island on cross-country skis. He won international fame after reaching a record northern latitude of 86°14′ during his ''Fram'' expedition of 1893–1896. Although he retired from exploration after his return to Norway, his techniques of polar travel and his innovations in equipment and clothing influenced a generation of subsequent Arctic and Antarctic expeditions. Nansen studied zoology at the Royal Frederick University in Christiania and later worked as a curator at the University Museum of Bergen where his research on the central nervous system of lower marine creatures earned him a doctorate and helped establish neuron doctrine. Later, neuroscientist Sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nansen's Fram Expedition
Nansen's ''Fram'' expedition of 1893–1896 was an attempt by the Norwegian explorer Fridtjof Nansen to reach the geographical North Pole by harnessing the natural east–west current of the Arctic Ocean. In the face of much discouragement from other polar explorers, Nansen took his ship ''Fram'' to the New Siberian Islands in the eastern Arctic Ocean, froze her into the pack ice, and waited for the drift to carry her towards the pole. Impatient with the slow speed and erratic character of the drift, after 18 months Nansen and a chosen companion, Hjalmar Johansen, left the ship with a team of Samoyed dogs and sledges and made for the pole. They did not reach it, but they achieved a record Farthest North latitude of 86°13.6′N before a long retreat over ice and water to reach safety in Franz Josef Land. Meanwhile, ''Fram'' continued to drift westward, finally emerging in the North Atlantic Ocean. The idea for the expedition had arisen after items from the American vessel ''Je ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluid Dynamics
In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids— liquids and gases. It has several subdisciplines, including ''aerodynamics'' (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation. Fluid dynamics offers a systematic structure—which underlies these practical disciplines—that embraces empirical and semi-empirical laws derived from flow measurement and used to solve practical problems. The solution to a fluid dynamics problem typically involves the calculation of various properties of the fluid, such as flow velocity, pressure, density, and temperature, as functions of space and time. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Uppsala
Uppsala University ( sv, Uppsala universitet) is a public research university in Uppsala, Sweden. Founded in 1477, it is the oldest university in Sweden and the Nordic countries still in operation. The university rose to significance during the rise of Sweden as a great power at the end of the 16th century and was then given a relative financial stability with a large donation from King Gustavus Adolphus in the early 17th century. Uppsala also has an important historical place in Swedish national culture, identity and for the Swedish establishment: in historiography, literature, politics, and music. Many aspects of Swedish academic culture in general, such as the white student cap, originated in Uppsala. It shares some peculiarities, such as the student nation system, with Lund University and the University of Helsinki. Uppsala belongs to the Coimbra Group of European universities and to the Guild of European Research-Intensive Universities. It has ranked among the world' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physics
Physics is the natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events." Physics is one of the most fundamental scientific disciplines, with its main goal being to understand how the universe behaves. "Physics is one of the most fundamental of the sciences. Scientists of all disciplines use the ideas of physics, including chemists who study the structure of molecules, paleontologists who try to reconstruct how dinosaurs walked, and climatologists who study how human activities affect the atmosphere and oceans. Physics is also the foundation of all engineering and technology. No engineer could design a flat-screen TV, an interplanetary spacecraft, or even a better mousetrap without first understanding the basic laws of physic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanography
Oceanography (), also known as oceanology and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics; plate tectonics and the geology of the sea floor; and fluxes of various chemical substances and physical properties within the ocean and across its boundaries. These diverse topics reflect multiple disciplines that oceanographers utilize to glean further knowledge of the world ocean, including astronomy, biology, chemistry, climatology, geography, geology, hydrology, meteorology and physics. Paleoceanography studies the history of the oceans in the geologic past. An oceanographer is a person who studies many matters concerned with oceans, including marine geology, physics, chemistry and biology. History Early history Humans first acquired knowledge of the waves and currents of the seas and oceans in pre-historic times. Observations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fredrik Laurentz Ekman
Fredrik is a masculine Germanic given name derived from the German name '' Friedrich'' or Friederich, from the Old High German ''fridu'' meaning "peace" and ''rîhhi'' meaning "ruler" or "power". It is the common form of Frederick in Norway, Finland and Sweden. The name means "peaceful ruler" The most common variant spelling of this name is Frederik which is used in Denmark, although the English spelling Frederick is more common than either. Fredrik replaced the Anglo-Saxon name Freodheric, and has been a rare first name in England since this time. In Sweden, Fredrik first fell into usage in the 14th century, and became increasingly common after the 18th century. It is the 19th most popular male name in Sweden and the 41st most popular in Norway. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
