Рис. spirale f d ́Ekman s espiral f de Ekman g Ekman-Spirale f El Niño; southern oscillation The abnormal warming of ocean water off the west coast of. Vagn Walfrid Ekman Category:Ekman spiral cawiki Espiral d’Ekman; dewiki Korkenzieherströmung; enwiki Ekman spiral; eswiki Espiral de Ekman; etwiki. elbow EHT~; – rectffier u TV válvula rectificadora de MAT/; – supply n rv spiral n OCEAN espiral de Ekman m elaeolite n MINERAL eleolita / nefelma.
|Published (Last):||8 April 2017|
|PDF File Size:||3.83 Mb|
|ePub File Size:||18.47 Mb|
|Price:||Free* [*Free Regsitration Required]|
Modelling the mixed layer response”. Walfrid Ekman who first described the spiral in The depth to which the Ekman spiral penetrates is determined by how far turbulent mixing can penetrate over the course of a pendulum day.
The effect is a consequence of the Coriolis effect which subjects moving objects to an apparent force to the right of their direction of motion in the northern hemisphere and to the left in the Southern Hemisphere. The example shown above is for the Northern Hemisphere.
Skip to main content. It was moving consistently to the right of the wind direction. You are here Home. This image is a work of a sailor or employee of the U. Surface winds in the Northern Hemisphere tend to blow to the left of winds aloft.
Eventually, the current will reach a esplral speed when the force of the wind, of the Coriolis effect, and the resistant drag of espirl subsurface water balance, and the current will flow at a constant speed and direction as long as the wind persists. Wind-induced water movements in a Benguela kelp bed. File File history File usage No higher resolution available.
From Wikipedia, the free encyclopedia. It derives its name from ekkman Swedish oceanographer Vagn Walfrid Ekman. An Ekman spiral A is a rotating column of water espirao forms when water moves at an angle to the wind direction due to the Coriolis Effect. Views Read Edit View history. Wikimedia Commons has media related to Ekman spiral. The Ekman spiral is a structure of currents or winds near a horizontal boundary in which the flow direction rotates as one moves away from the boundary.
No pages on the English Wikipedia link to this file. Views Read Edit View history.
This page was last edited on 25 Augustat The first documented observations of an oceanic Ekman spiral were made in the Arctic Ocean from a drifting ice floe in Ocean water at the surface moves at an angle to the wind, and the water under the surface water turns a bit more, and the water below that turns even more. From Wikipedia, the free encyclopedia. Thus, when a persistent wind blows over an extended area of the ocean surface in the northern hemisphere, it causes a surface current which accelerates in that direction, which then experiences a Coriolis force and acceleration to the right of the wind: This is due both to the fact that the turbulent mixing in the surface layer of the ocean has a strong diurnal cycle and to the fact that surface waves can destabilize the Ekman spiral.
Espiral d’Ekman – Viquipèdia, l’enciclopèdia lliure
If this media is not useful, please propose it for deletion or list it at files for discussion. Journal of Physical Oceanography. If the file lacks a description you can check edits the uploader made just after uploading this file with this tool.
Journal of Geophysical Research.
The average direction of all this turning water is about a right angle from the wind direction. Because the Earth rotates, surface water moves to the right of the wind direction in the Northern Hemisphere and to the left of the wind direction in the Southern Hemisphere due to the Coriolis effect. As the flow is now somewhat right of the wind, the Coriolis force perpendicular to the espjral motion is now partly directed against the wind.
This media file is either in ek,an public domain or published under a free licenseand contains no inbound file links. The force from above is in red beginning with the wind blowing over the water surfacethe Coriolis force which is shown at right angles to the force from above when it should in fact be at right angles to the actual water flow is in dark yellow, and the net resultant water movement is in pink, which then becomes the force from above for the layer below it, accounting for the gradual clockwise spiral motion as you esprial down.
This surface eekman drags on the water layer below it, applying a force in its own direction of motion to that layer, repeating the process whereby that layer eventually becomes a steady current even further to the right of the wind, and so on for deeper layers of water, resulting in a continuous rotation or ekmwn of current direction with changing depth.
Moving files to Commons for details. The Ekman spiral and Ekman transport are named for Swedish scientist V. He thought that trapped in sea ice, which moves with ocean currents, he would get to the North Pole eventually.
How Seawater Moves: Ekman Transport | UCAR Center for Science Education
The diagram above attempts to show the forces associated with the Ekman spiral as applied to the Northern hemisphere. If this file has problems with attributioncopyrightor is otherwise ineligible for Commons, then remove this tag and DO NOT transfer it; repeat violators may be blocked from editing.
As depth increases, the force transmitted from the driving wind declines and thus the speed of the resultant steady current decreases, hence the tapered spiral representation in the accompanying diagram. On the influence of the Earth’s rotation on ocean currents.
Camada de Ekman
The deflection of surface currents was first noticed by the Norwegian oceanographer Fridtjof Nansen during the Fram expedition — and the effect was first physically explained by Vagn Walfrid Ekman.