Zonda wind
Encyclopedia
Zonda wind is a regional term for the foehn wind
that often occurs on the eastern slope of the Andes
, in Argentina
. The Zonda is a dry wind (often carrying dust) which comes from the polar
maritime
air, warmed by descent from the crest, which is some 6,000 m (18,000 ft) above sea level
. It may exceed a velocity of 40 km/h (25 mph).
While this type of föhn wind may occur over most central parts of western Argentina, its effects are more impressive in La Rioja
, San Juan
, and northern Mendoza
provinces, where the mountain barrier (the Andes) is higher, while to the north the Puna plateau
dissipates these winds.
The Zonda wind is basically produced by the northeastward movement of polar fronts, and although is hot and dry at the low-lands, it is the main mechanism for snow
precipitation at the high altitude chains, where it looks as viento blanco, reaching speeds sometimes over 200 km/h. Thus, instead of being a snow-eater, this wind is particularly important for this arid
region, as it is connected to the buildup of the winter snow cover and accumulation over the scarce local glacier
s.
According to studies (conducted over the period 1967–1976), the Zonda wind most commonly starts during the afternoon (between 12 and 6 PM), and tends to last between 1 and 12 hours, though it may present itself intermittently for as long as 2 or 3 days. It is countered usually by the entrance of cold air masses moving northwestward (viento sur). In 90% of the cases, the phenomenon takes place between May and November.
. This wind is also called the sondo.
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...
that often occurs on the eastern slope of the Andes
Andes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
, in Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
. The Zonda is a dry wind (often carrying dust) which comes from the polar
South Pole
The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole...
maritime
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
air, warmed by descent from the crest, which is some 6,000 m (18,000 ft) above sea level
Sea level
Mean sea level is a measure of the average height of the ocean's surface ; used as a standard in reckoning land elevation...
. It may exceed a velocity of 40 km/h (25 mph).
While this type of föhn wind may occur over most central parts of western Argentina, its effects are more impressive in La Rioja
La Rioja Province (Argentina)
La Rioja is a one of the provinces of Argentina and is located in the west of the country. Neighboring provinces are from the north clockwise Catamarca, Córdoba, San Luis and San Juan.-History:...
, San Juan
San Juan Province (Argentina)
San Juan is a province of Argentina, located in the western part of the country. Neighbouring provinces are, moving clockwise from the north, La Rioja, San Luis and Mendoza. It borders with Chile at the west....
, and northern Mendoza
Mendoza Province
The Province of Mendoza is a province of Argentina, located in the western central part of the country in the Cuyo region. It borders to the north with San Juan, the south with La Pampa and Neuquén, the east with San Luis, and to the west with the republic of Chile; the international limit is...
provinces, where the mountain barrier (the Andes) is higher, while to the north the Puna plateau
Altiplano
The Altiplano , in west-central South America, where the Andes are at their widest, is the most extensive area of high plateau on Earth outside of Tibet...
dissipates these winds.
The Zonda wind is basically produced by the northeastward movement of polar fronts, and although is hot and dry at the low-lands, it is the main mechanism for snow
Snow
Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by...
precipitation at the high altitude chains, where it looks as viento blanco, reaching speeds sometimes over 200 km/h. Thus, instead of being a snow-eater, this wind is particularly important for this arid
Arid
A region is said to be arid when it is characterized by a severe lack of available water, to the extent of hindering or even preventing the growth and development of plant and animal life...
region, as it is connected to the buildup of the winter snow cover and accumulation over the scarce local glacier
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
s.
According to studies (conducted over the period 1967–1976), the Zonda wind most commonly starts during the afternoon (between 12 and 6 PM), and tends to last between 1 and 12 hours, though it may present itself intermittently for as long as 2 or 3 days. It is countered usually by the entrance of cold air masses moving northwestward (viento sur). In 90% of the cases, the phenomenon takes place between May and November.
Alternative usage
The term zonda also describes a hot, humid north wind in the Pampas, in advance of a depression moving eastwards, and preceding the pamperoPampero
Pampero may refer to:* The Pampero Winds* Industrias Pampero, C.A., rum distillery in Venezuela...
. This wind is also called the sondo.
See also
- Zonda DepartmentZonda Department'Zonda is a department of the province of San Juan . It is located in the center south of the province, which stressed a landscape of hills and little vegetation...
, a department of the province of San Juan, Argentina. - Pagani ZondaPagani ZondaThe Pagani Zonda is a sports car built by the Italian manufacturer Pagani. It debuted in 1999, and production ended in 2011. As of June 2009, 206 Zondas had been built, including test mules. Both 2-seat coupe and convertible versions have been produced. Construction is mainly of carbon...
, a sports carSports carA sports car is a small, usually two seat, two door automobile designed for high speed driving and maneuverability....
which takes its name from the wind. - Puelche windPuelche (wind)A Puelche wind is a dry foehn-like eastern wind that occurs in south-central Chile. The wind owns its name from the Puelche people that inhabited the eastern slopes of the Andes. Puelche is mainly caused by South Pacific high pressure extending eastwards across the Andes and/or building a ridge to...
- Autódromo El Zonda - Eduardo Copello, a race track located in San Juan, Argentina.