HOME

TheInfoList



OR:

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 List of South American countries by area, second-largest ...
.


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 cli ...
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 Pri ...
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 standardis ...
. 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 throughou ...
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 ...
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 over many years, often centuries. It acquires distinguishing features, such a ...
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, an ...
,
San Juan San Juan, Spanish for Saint John, may refer to: Places Argentina * San Juan Province, Argentina * San Juan, Argentina, the capital of that province * San Juan, Salta, a village in Iruya, Salta Province * San Juan (Buenos Aires Underground), ...
, 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, in advance of a depression moving eastwards, and preceding the pampero. This wind is also called the ''sondo''.


See also

* Zonda Department, a department of the province of San Juan, Argentina. * Pagani Zonda, a sports car which takes its name from the wind. * Puelche wind * Southeast Australian foehn


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