The apparent compulsion for people to give a wind a name fascinates me. It seems to indicate a connection between population and place, with nature, environment, weather, climate and season all playing a part.
The practice appears to be universal.
What is wind?
According to the National Geographic, wind is the movement of air, caused by the uneven heating of the Earth by the sun and the Earth’s own rotation including the seasonal migration of climatic zones. It is the mechanism of equalising areas of differing air pressure which is itself caused by differential heating of adjacent areas. Warm air rises and results in lower pressure, cold air descends and results in higher pressure. Nature abhors a vacuum so wind flows from the latter to the former.
There is a type of wind called a Foehn or Föhn wind. The word was originally used to describe warm descending winds on the northern, leeward slopes of the European Alps bringing relatively warm conditions to Switzerland, Austria and southern Germany.
There are examples of Foehn winds on all continents.
One of my favourite examples of a Foehn wind comes from North America. Moisture laden air blows from west to east over the Pacific, it rises over the Rockies and as it does so, it cools. Eventually the air cools below the point at which it can hold the moisture (its dew point) and the water precipitates as rain or snow. As the air continues eastward it falls down the leeward slopes and warms, by this time the air is dryer and as it descends, its rate of warming is faster than the rate of cooling the rising humid air.
The process in changes in temperature caused by the expansion (cooling) or compression (warming) of a body of air as it rises or descends in the atmosphere, is called Adiabatic. The Adiabatic rates of cooling and warming are not the same for moist or dry bodies of air.
The resulting relatively warm wind which blows down the eastern side of the Rockies is called the Chinook or the ‘snow eater’. Cumulated snow on the Great Plains can melt remarkably rapidly.
Other commonly heard named winds
Someone, presumably in the marketing department, of a famous automobile company, apparently also afflicted by a fascination with named winds, came up with a system of naming its models:
- Golf is an apparent reference to the Gulf Stream which is partly driven by wind and is responsible for milder temperatures than may otherwise be expected for latitudes in large parts of western Europe. Bringing us in the UK warm, wet, westerly winds in winter.
- Jetta is German for ‘jet stream’, a high-level movement of air from southwest to northeast in the stratosphere.
- Passat means ‘trade wind’. The trade winds blow from northeast to southwest in the northern hemisphere and converge at the equator with winds which blow from southeast to northwest in the southern hemisphere. The trades were particularly important when marine trade was carried out by sail.
- Scirocco is named after Sirocco, a warm humid Mediterranean wind.
- Polo is a reference to polar winds.
- Bora is a cold north or north easterly wind in the Adriatic coast of the Balkans. The name has been used by more than one automobile manufacturer.
The link between named winds and transport is not confined to automobiles. A French express train service between Paris and the south of France was named after the Mistral, a strong wind caused by pressure differences over the Bay of Biscay and the Mediterranean, the wind gathered speed and strength as it was funnelled through the valley of the Rhone. Mistral has also been used for a model by another automobile manufacturer.
The Beast from the East
Not strictly a wind, it is the name given to cold, stormy and wintry conditions brought about by high pressure conditions over continental Europe which result in cold winds affecting the UK.
Saharan dust and its travels
There is a wind called the Harmattan or dry Harmattan which generally blows late in the year over the Sahara Desert in North Africa and often raises dust storms. Normally the wind blows from northeast to southwest or east to west but when large dust storms coincide with some southerly air movements, the dust can be carried at altitude over a very wide area.
According to the Met Office, Saharan dust is “relatively common in the UK often happening several times a year”. The dust can also be carried across the Atlantic as far as South America and the Caribbean.
Land and sea breezes
The land and the sea warm and cool at differing rates which gives rise to winds called land and sea breezes.
One such sea breeze is the ‘Freemantle Doctor’ – a cooling wind which blows off the Indian Ocean and occurs in the evening, offering relief from high daytime temperatures near Perth’s port in Western Australia.
Less welcome are land breezes such as the Sundowner, a northern offshore wind in California that commences in the evening near sunset, when onshore sea breezes abate and offshore flows pick up. Sundowners often have destructive effects during wildfire seasons.
Climate change and the wind
What effect will climate change have on the wind? Will we lose some of our named winds? Will they move? Will there be new winds and names?
Will energy from the wind itself play a part in the mitigation of climate change? If so to what extent and over what timeframe?