question: How does wind "happen"?
comment: The different densities of the air, due to their different temperatures, cause air pockets to move about as they shift, similar to how water and oil don't mix and end up seprerated.
passages: Section::::Usage.:Recreation.
   BULLET::::- "Nor'easter" (strong storm with winds from the northeast on the north eastern coast of the United States (particularly New England states) and the east coast of Canada (Atlantic Canada))
  
  BULLET::::- "Nor'wester" (wind that brings rain to the West Coast, and warm dry winds to the East Coast of New Zealand's South Island, caused by the moist prevailing winds being uplifted over the Southern Alps, often accompanied by a distinctive arched cloud pattern)
  
  Section::::O-R.
  
  BULLET::::- (strong katabatic wind across the Kanto Plain)
  
  BULLET::::- "Ostro" (southerly wind in the Mediterranean)
   Section::::Origin.
   Section::::Wind Rose.
   Section::::Local examples.
  
  Regionally, these winds are known by many different names. These include:
  
  BULLET::::- in Africa
  
  BULLET::::- Bergwind in South Africa
  
  BULLET::::- in the Americas
  
  BULLET::::- The Brookings Effect on the southwestern coast of Oregon, also known as the Chetco Effect.
  
  BULLET::::- Chinook winds east of the Rocky Mountains and the Cascade Range in the United States and Canada, and north, east and west of the Chugach Mountains of Alaska, United States
   Section::::Causes.
   Section::::Composition.
  
  Section::::Composition.:Concept.
   Section::::Role in the natural world.:Desert dust migration.
   Section::::Local considerations.:Circulation in elevated regions.
   Section::::Role in the natural world.
   Section::::On other planets.
   Section::::Composition.:Music and lyrics.
   Section::::Causes.:Isentropic draw-down.
  
  Isentropic draw-down is the draw-down of warmer, drier air from aloft. When the approaching winds are insufficiently strong to propel the low-level air up and over the mountain barrier, the airflow is said to be 'blocked' by the mountain and only air higher up near mountain-top level is able to pass over and down the lee slopes as foehn winds. These higher source regions provide foehn air that becomes warmer and drier on the leeside after it is compressed with descent due to the increase in pressure towards the surface.
  
  Section::::Causes.:Mechanical mixing.
   Section::::Release and touring.
   Section::::Shear.
  
  Wind shear, sometimes referred to as wind gradient, is a difference in wind speed and direction over a relatively short distance in the Earth's atmosphere. Wind shear can be broken down into vertical and horizontal components, with horizontal wind shear seen across weather fronts and near the coast, and vertical shear typically near the surface, though also at higher levels in the atmosphere near upper level jets and frontal zones aloft.
   Section::::1969 film version.
   BULLET::::- "Calima" (dust-laden south to southeasterly wind blowing in the Saharan Air Layer across the Canary Islands)
  
  BULLET::::- "Carpinteiro" (strong southeasterly wind along the southern Atlantic coast of Brazil)
  
  BULLET::::- "Cape Doctor" (dry south-easterly wind that blows on the South African coast in summer)
  
  BULLET::::- "Cers" (strong, very dry northeasterly wind in the bas-Languedoc region in southern France)
  
  BULLET::::- "Chetco Effect" (alternate term for Brookings Effect, off-shore wind on the southwestern Oregon coast, United States)
  
  BULLET::::- "Chinook" (warm dry westerly off the Rocky Mountains)
  
  BULLET::::- "Cierzo" (cool north/northwesterly wind on Ebro Valley in Spain)
   Section::::Background.
  
  Typically, due to aerodynamic drag, there is a wind gradient in the wind flow, especially in the first few hundred meters above the Earth's surface—the surface layer of the planetary boundary layer. Wind speed increases with increasing height above the ground, starting from zero due to the no-slip condition. Flow near the surface encounters obstacles that reduce the wind speed, and introduce random vertical and horizontal velocity components at right angles to the main direction of flow.
   Section::::Description.
   Section::::Description.
  
  Section::::Description.:Physical explanation.
   BULLET::::- Foehn winds in the foothills of the southern Appalachian mountains, which can be unusual compared to other foehn winds in that the relative humidity typically changes little due to the increased moisture in the source air mass
  
  BULLET::::- The Santa Ana winds of southern California, including the Sundowner winds of Santa Barbara, are in some ways similar to the Föhn, but originate in dry deserts as a katabatic wind.
  
  BULLET::::- Puelche wind in Chile
  
  BULLET::::- Suêtes on the west coast of Cape Breton Island, Nova Scotia, Canada
  
  BULLET::::- Zonda winds in Argentina
  
  BULLET::::- in Antarctica
   BULLET::::- "East Asian Monsoon", known in Korea as "jangma" (), and in Japan as when advancing northwards in the spring and when retreating southwards in autumn.
  
  BULLET::::- "Monsoon of South Asia"
  
  BULLET::::- "N'aschi" (northeastern wind on the Iranian coast of the Persian Gulf, and on the Makran coast)
  
  BULLET::::- "Nigeq" (a strong wind from the east in Greenland)
  
  BULLET::::- "Norte" (strong cold northeasterly wind in Mexico)
  
  BULLET::::- North wind (northern cold winds blowing from the Gulf of Mexico to the Isthmus of Tehuantepec)
   Section::::Opinions.
   BULLET::::- "Santana winds" (southern California) (Sometimes referred to as 'Santa Ana Winds' after a nearby town)
  
  BULLET::::- "Santa Lucia winds" (a downslope wind affecting southern San Luis Obispo and northern Santa Barbara Counties, California)
  
  BULLET::::- "Sarma" (cold strong wind at the western shore of Lake Baikal)
  
  BULLET::::- "Shamal" (a summer northwesterly wind blowing over Iraq and the Persian Gulf states)
  
  BULLET::::- "Sharqi" (seasonal dry, dusty Middle Eastern wind coming from the south and southeast)
  
  BULLET::::- "Simoom" (Samiel) (strong, dry, desert wind that blows in Israel, Jordan, Syria, and the desert of Arabia)
   Section::::Role in the natural world.:Effect on animals.
  