Zonda wind ( es, viento zonda) is a regional term for the
foehn wind
A Foehn or Föhn (, , ), is a type of dry, relatively warm, downslope wind that occurs in the lee (downwind side) of a mountain range.
It is a rain shadow wind that results from the subsequent adiabatic warming of air that has dropped most of ...
that often occurs on the eastern slope of the
Andes
The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...
, in
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
.
Formation
The Zonda is a dry wind (often carrying dust) which comes from the
polar
Polar may refer to:
Geography
Polar may refer to:
* Geographical pole, either of two fixed points on the surface of a rotating body or planet, at 90 degrees from the equator, based on the axis around which a body rotates
* Polar climate, the c ...
maritime
Maritime may refer to:
Geography
* Maritime Alps, a mountain range in the southwestern part of the Alps
* Maritime Region, a region in Togo
* Maritime Southeast Asia
* The Maritimes, the Canadian provinces of Nova Scotia, New Brunswick, and Princ ...
air, warmed by descent from the crest, which is approximately above
sea level
Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised g ...
. It may exceed a velocity of .
The Zonda wind is 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 comprises individual ice crystals that grow while suspended in the atmosphere—usually within clouds—and then fall, accumulating on the ground where they undergo further changes.
It consists of frozen crystalline water throughout ...
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
A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ar ...
region, as it is connected to the buildup of the winter snow cover and accumulation over the scarce local
glacier
A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its Ablation#Glaciology, ablation over many years, often Century, centuries. It acquires dis ...
s.
Occurrence
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 () is an autonomous community and province in Spain, in the north of the Iberian Peninsula. Its capital is Logroño. Other cities and towns in the province include Calahorra, Arnedo, Alfaro, Haro, Santo Domingo de la Calzada, and Nà ...
,
San Juan, and northern
Mendoza provinces, where the mountain barrier (the Andes) is higher, while to the north the
Puna plateau dissipates these winds.
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
The Pampas (from the qu, pampa, meaning "plain") are fertile South American low grasslands that cover more than and include the Argentine provinces of Buenos Aires, La Pampa, Santa Fe, Entre RÃos, and Córdoba; all of Uruguay; and Brazil ...
, in advance of a depression moving eastwards, and preceding the
pampero. This wind is also called the ''sondo''.
See also
*
Zonda Department
Zonda Department (Spanish: ''Departamento Zonda'') is an administrative department of San Juan Province in Argentina. Zonda is located in the south of the province, bordered by Ullum Department to the north, Sarmiento Department to the south, C ...
, a department of the province of San Juan, Argentina.
*
Pagani Zonda
The Pagani Zonda is a mid-engine sports car produced by the Italian sports car manufacturer Pagani. It debuted at the 1999 Geneva Motor Show. By 2019, a total of 140 cars had been built, including development mules. Both 2-door coupé and r ...
, a sports car which takes its name from the wind.
*
Puelche wind
*
Southeast Australian foehn
The southeast Australian foehn is a westerly foehn wind and a rain shadow effect that usually occurs on the coastal plain of southern New South Wales, and as well as in eastern Victoria and eastern Tasmania, on the leeward side of the Great Divid ...
References
*
MeteoBlogs – ''Viento Zonda'' National Meteorological Service, Air Regions Command, Argentine Air Force.
Article.
{{coord missing, Argentina
Climate of Argentina
Föhn effect
Mendoza Province
Winds