The contralysian winds are constant winds located in the upper part of the atmosphere -troposphere-, which move above and in the opposite direction to the trade winds.
These winds blow to the northeast in the northern hemisphere and to the southeast in the southern hemisphere, between 30 and 60 degrees latitude.
Together with these winds and the circumpolar winds they form the planetary winds, responsible for the transport in large masses of the thermal energy from the infrared rays of the sun.
They originate thanks to the ascent of great masses of warm air from the equator by convergence law.
What is the function of the contralysian winds?
The function of the contralisios is the transport of thermal energy through the different cells that make up the Earth's atmospheric circulation system.
After large masses of warm air rise from near the equator, they move eastward horizontally due to the centrifugal motion of the Earth.
The winds are directed towards the poles, above the earth's surface at about 10-15 km altitude.
When these air masses reach 30 degrees north or south latitude (respectively), they descend to the surface, blowing into the subtropics.
Then these winds flow towards the low pressure belt that forms on the surface of the intertropical zone due to the law of convergence, where the cold and dry air found in the temperate zones replaces the warm and humid air that rises from the proximity to the equator.
These winds change their direction thanks to the Coriolis effect and become trade winds, heading towards the west and moving horizontally towards the equator.
When approaching the equator, the trade winds from the northern hemisphere converge with the trade winds from the southern hemisphere, forming the so-called Intertropical Convergence Zone (ZGIT), which forms an upward current of warm and humid air.
These currents form large air masses that become counter-winds, closing the cycle.
This process is known as the Atmospheric Circulation System or Hadley Cell.
Behavior and characteristics
Contralisios are warm winds that blow constantly towards the north and south poles, respectively, always with an eastward direction. This is thanks to the centrifugal movement of the Earth that causes a Coriolis effect in its atmosphere.
These winds are opposite to the trade winds and blow over them in an atmospheric circulation system known as the Hadley Cell, displacing clouds known as cirrus.
During the year, the contralysios vary in strength in proportion to the polar cyclones. When cyclones reach their maximum intensity during winter, the contralisios blow with greater intensity over temperate zones.
When cyclones reach their lowest intensity during the summer, the contralisions weaken.
They are particularly strong in the mid-latitudes of the southern hemisphere because there is so little soil to cause friction and slow these winds.
They drive ocean currents located on subtropical ridges and are known as The roaring forties by English sailors, due to the force with which they displace large amounts of water between 40 and 50 degrees latitude in both hemispheres.
References
- Bjerknes, Jacob. 1935. The atmospheric circulation in the sous-tropical latitudes. Scientia. 57. p. 114-123.
- Retrieved on: October 11, 2017, from Vocabulary: vocabulary.com
- Retrieved on: October 11, 2017, from Wikipedia: wikipedia.org
- Hadley Cell. Retrieved on: October 11, 2017, from Wikipedia: wikipedia.org
- Hadley cell. Retrieved on: October 11, 2017, from Windows2Universe: windows2universe.org
- George Cramoisi 2009. Air Crash Investigations. 2.2 Storm activity in the ITCZ.