Rossby (or planetary) waves are large-scale motions in the ocean or atmosphere whose restoring force is the variation in Coriolis effect with latitude. If Rossby waves were more commonly called planetary waves, it would reduce confusion. The waves were first identified in the atmosphere in the 1939 by Carl-Gustaf Arvid Rossby who went on to explain their motion. Ocean (from Okeanos, a Greek god of sea and water; Greek ωκεανός) covers almost three quarters (71%) of the surface of the Earth, and nearly half of the worlds marine waters are over 3000 m deep. ... Layers of Atmosphere (NOAA) Earths atmosphere is the layer of gases surrounding the planet Earth and retained by the Earths gravity. ... Hurricane Isabel east of the Bahamas on September 15, 2003. ... Latitude, denoted by the Greek letter φ, gives the location of a place on Earth north or south of the Equator. ... Layers of Atmosphere (NOAA) Earths atmosphere is the layer of gases surrounding the planet Earth and retained by the Earths gravity. ... 1939 was a common year starting on Sunday (link will take you to calendar). ... Carl-Gustav Arvid Rossby (December 28, 1898 – August 19, 1957) was a Swedish-US meteorologist who first explained the large_scale motions of the atmosphere in terms of fluid mechanics. ...

Terrestrial waves

The direction of rotation of the Earth entails that such wave crests always travel East to West. However, the energy associated with the waves can propagate in any direction. In general: shorter waves propagate energy to the east; longer waves propagate energy to the west. Rotation is the movement of a body in such a way that the distance between a certain fixed point and any given point of that body remains constant. ... Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third-closest planet to the Sun. ... The group velocity of a wave is the velocity with which the overall shape of the waves amplitude (known as the envelope of the wave) propagates through space. ...

Atmospheric waves

Rossby waves in the atmosphere are easy to observe as large-scale meanders of the jet stream. When these loops become very pronounced, they detach the masses of cold, or warm, air that become cyclones and anticyclones and are responsible for day-to-day weather patterns at mid-latitudes. Jet streams are fast flowing, relatively narrow air currents found in the atmosphere at around 12 km above the surface of the Earth, just under the tropopause. ... In meteorology, a cyclone is the rotation of a volume of air about an area of low atmospheric pressure. ... In meteorology, an anticyclone is a weather phenomenon associated with atmospheric high pressure. ...

The wave speed is given by:

Where c is the wave speed, u is the mean westerly flow, β is the Rossby parameter, and k is the total wavenumber. The Rossby parameter is a nondimensional number used in geophysics and meteorology which arises due to the northward variation of the Coriolis force caused by the spherical shape of the Earth. ...

Oceanic waves

In the oceans, Rossby waves are responsible for the asymmetry of circulatory vortices in which the Western arm of a vortex is narrower and flows more rapidly than the Eastern. This western intensification is the effect that drives the Gulf Stream. It was elucidated by Henry M. Stommel who termed it the beta effect. Vortex created by the passage of an aircraft wing, revealed by coloured smoke A vortex is a spinning turbulent flow (or any spiral whirling motion) with closed streamlines. ... Vortex created by the passage of an aircraft wing, revealed by coloured smoke A vortex is a spinning turbulent flow (or any spiral whirling motion) with closed streamlines. ... For the album by Ocean Colour Scene, see North Atlantic Drift (album) The Gulf Stream is orange and yellow in this representation of water temperatures of the Atlantic. ...

Rossby waves are generated by atmospheric forcing from winds and buoyancy effects from solar heating and are the principal means by which localised climatic effects drive the global response of the ocean. Waves propagate at only a few centimetres per second, have wavelengths of up to hundreds of kilometres and result in only a few centimetres elevation at the sea surface. However, their passage can result in displacements of the thermocline of the order of many meters. Wind is the quasi-horizontal movement of air (as opposed to an air current) caused by a horizontal pressure gradient force. ... your a smelly bum ratIn physics, buoyancy is an upward force on an object immersed in a fluid (i. ... A centimetre (American spelling: centimeter, symbol: cm) is an SI unit of length. ... The second (symbol s) is a unit for time, and one of seven SI base units. ... The wavelength is the distance between repeating units of a wave pattern. ... A kilometre (American spelling: kilometer, symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure). ... The thermocline is a layer within a body of water where the temperature changes rapidly with depth. ...

Bibliography

• Rossby, C-G (1939), Relation between variations in the intensity of the zonal circulation of the atmosphere and the displacements of the semi-permament centers of action, J. Marine Resarch pp38-55
• Platzman, G (1968) The Rossby wave, Quart. J. Roy. Meteorol. Soc. pp94-248
• Dickinson, R E (1978) Rossby waves - long-period oscillations of oceans and atmospheres, Ann. Rev. Fluid Mech. pp10-195

See also

• atmospheric wave

An atmospheric wave is a periodic disturbance in the fields of atmospheric variables (like surface pressure or geopotential height, temperature, or wind velocity) which may either propagate (traveling wave) or not (stationary wave). ...

External Links

Rossby Waves, from the American Meterological Society

An introduction to oceanic Rossby waves and their study with satellite data