Under certain conditions, powerful winds form over the Sahara desert in North Africa and move northward and eastward across the Mediterranean Sea. On their journey, the winds pick up moisture and blow humidity and heat into many countries on the north shore of the Mediterranean. These winds are generally called siroccos, though they have other names in the various lands they touch and affect.
Siroccos form behind atmospheric depressions in northern Africa, Arabia or the southern Mediterranean. These depressions draw the air from above the desert, creating what is initially a dry, hot, dusty wind, giving the North African coast it characteristic dryness. Moving northward across the Mediterranean, these winds pick up moisture and deliver hot, humid, devitalizing air to southern Europe. In the cooler months, the air cools and causes wet, cool blasts to Europe. Sirocco gales on average last 12 hours and sometimes last as long as 36 hours.
Siroccos are usually unpleasant. They sometimes reach 100 km/h (62 mph) in spring and to a lesser degree in the fall. They attain their peaks in March and November. The high-velocity winds can cause severe damage. A sirocco can produce sand storms and initially carry much dust. Particle-laden high-speed winds can damage buildings and disable machinery. In Europe, where siroccos can be felt as cold winds, health problems can ensue. When felt as hot and humid air, siroccos can cause insomnia and headaches.
Sirocco is the most common name for the wind, though the alternative scirocco is also used. Both are Italian words which may derive from an Arabic word meaning “eastern,” since the winds move from west to east. Other names for the winds are leveche in Spain and jugo in the Balkans. The Libyan name is ghibli. They are called xaroco in Portugal and, in France, marin.
Special clothing and equipment have been developed for dealing with sirocco winds. Lightweight windbreakers with elastic around the cuffs and hoods prevent the intrusion of dust and sand are sold. Home wind-speed meters capable of measuring the most powerful siroccos are also available.
The name sirocco has been borrowed for other uses. Volkswagen sells a sporty compact car named the Sirocco. A New Zealand winery is called Sirocco Wines. A 1951 film entitled “Sirocco” starred Humphrey Bogart. In 2008, Virginia Ann Work published a fiction novel set in the Mediterranean region entitled, “Sirocco Wind from the East,” although technically, Sirocco winds come from the southwest.
Sources:
http://ggweather.com/winds.html
http://mediatheek.thinkquest.nl/~ll118/en/development/types.list.sirocco.html
http://www.istrianet.org/istria/geosciences/meteorology/winds/sirocco.htm
http://www.christianbook.com/sirocco-from-east-keys-kingdom-series/virginia-work/9781604777796/pd/777796
