Vagn Walfrid Ekman
Encyclopedia
Vagn Walfrid Ekman 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 iceberg
s 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 and, 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 planet
ary rotation
.
On completing his doctorate in Uppsala in 1902, Ekman joined the International Laboratory for Oceanographic Research, Oslo
where he worked for seven years, not only extending his theoretical work but also developing experimental techniques and instruments such as the Ekman current meter
and Ekman water bottle
.
From 1910 to 1939 he continued his theoretical and experimental work at the University of Lund, where he was professor of mechanics and mathematical physics. He was elected a member of the Royal Swedish Academy of Sciences
in 1935.
A gifted amateur bass
singer, pianist
, and composer
, he continued working right up to his death in Gostad, near Stockaryd
, Sweden
.
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
oceanographer
Oceanography
Oceanography , also called oceanology or marine science, is the branch of Earth science that studies the ocean...
.
Born in Stockholm
Stockholm
Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...
to Fredrik Laurentz Ekman, himself an oceanographer, he became committed to oceanography
Oceanography
Oceanography , also called oceanology or marine science, is the branch of Earth science that studies the ocean...
while studying physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
at the University of Uppsala and, in particular, on hearing Vilhelm Bjerknes lecture on fluid dynamics
Fluid dynamics
In physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow—the natural science of fluids in motion. It has several subdisciplines itself, including aerodynamics and hydrodynamics...
.
During the expedition of the Fram
Nansen's Fram expedition
Nansen's Fram expedition, 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...
, Fridtjof Nansen
Fridtjof Nansen
Fridtjof Wedel-Jarlsberg Nansen was a Norwegian explorer, scientist, diplomat, humanitarian and Nobel Peace Prize laureate. In his youth a champion skier and ice skater, he led the team that made the first crossing of the Greenland interior in 1888, and won international fame after reaching a...
had observed that iceberg
Iceberg
An iceberg is a large piece of ice from freshwater that has broken off from a snow-formed glacier or ice shelf and is floating in open water. It may subsequently become frozen into pack ice...
s tend to drift not in the direction of the prevailing wind
Wind
Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space...
but at an angle of 20°-40° to the right. Bjerknes invited Ekman, still a student, to investigate the problem and, in 1905, Ekman published his theory of the Ekman spiral
Ekman spiral
The Ekman spiral refers to a structure of currents or winds near a horizontal boundary in which the flow direction rotates as one moves away from the boundary. It derives its name from the Swedish oceanographer Vagn Walfrid Ekman...
which explains the phenomenon in terms of the balance between frictional
Viscosity
Viscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...
effects in the ocean
Ocean
An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...
and the Coriolis force, which arises from planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
ary rotation
Rotation
A rotation is a circular movement of an object around a center of rotation. A three-dimensional object rotates always around an imaginary line called a rotation axis. If the axis is within the body, and passes through its center of mass the body is said to rotate upon itself, or spin. A rotation...
.
On completing his doctorate in Uppsala in 1902, Ekman joined the International Laboratory for Oceanographic Research, Oslo
Oslo
Oslo is a municipality, as well as the capital and most populous city in Norway. As a municipality , it was established on 1 January 1838. Founded around 1048 by King Harald III of Norway, the city was largely destroyed by fire in 1624. The city was moved under the reign of Denmark–Norway's King...
where he worked for seven years, not only extending his theoretical work but also developing experimental techniques and instruments such as the Ekman current meter
Ekman current meter
The Ekman current meter is a mechanical flowmeter invented by Vagn Walfrid Ekman a Swedish oceanographer, in 1903. It comprises a propeller with a mechanism to record the number of revolutions, a compass and a recorder with which to record the direction, and a vane that orients the instrument so...
and Ekman water bottle
Ekman water bottle
The Ekman water bottle is a sea water temperature sample device. The cylinder is dropped at the desired depth, the trap door below is opened to let the water enter and then closed tightly. This can be repeated at different depths as each sample goes to a different chamber of the insulated bottle.It...
.
From 1910 to 1939 he continued his theoretical and experimental work at the University of Lund, where he was professor of mechanics and mathematical physics. He was elected a member of the Royal Swedish Academy of Sciences
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...
in 1935.
A gifted amateur bass
Bass (voice type)
A bass is a type of male singing voice and possesses the lowest vocal range of all voice types. According to The New Grove Dictionary of Opera, a bass is typically classified as having a range extending from around the second E below middle C to the E above middle C...
singer, pianist
Pianist
A pianist is a musician who plays the piano. A professional pianist can perform solo pieces, play with an ensemble or orchestra, or accompany one or more singers, solo instrumentalists, or other performers.-Choice of genres:...
, and composer
Composer
A composer is a person who creates music, either by musical notation or oral tradition, for interpretation and performance, or through direct manipulation of sonic material through electronic media...
, he continued working right up to his death in Gostad, near Stockaryd
Stockaryd
Stockaryd is a locality situated in Sävsjö Municipality, Jönköping County, Sweden with 1,003 inhabitants in 2005....
, Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
.
See also
- Ekman spiralEkman spiralThe Ekman spiral refers to a structure of currents or winds near a horizontal boundary in which the flow direction rotates as one moves away from the boundary. It derives its name from the Swedish oceanographer Vagn Walfrid Ekman...
- Ekman numberEkman numberThe Ekman number is a dimensionless number used in describing geophysical phenomena in the oceans and atmosphere. It characterises the ratio of viscous forces in a fluid to the fictitious forces arising from planetary rotation...
- Ekman pumping
- Ekman layer
- Ekman transportEkman transportEkman transport, part of Ekman motion theory first investigated in 1902 by Vagn Walfrid Ekman , is the term given for the 90 degree net transport of the surface layer due to wind forcings...
- Dead waterDead waterDead water is the nautical term for a strange phenomenon which can occur when a layer of fresh or brackish water rests on top of denser salt water, without the two layers mixing. A ship powered by direct thrust under the waterline , traveling in such conditions may be hard to maneuver or can even...