Sahel (wind)
The Sahel is strong dust wind in the desert areas of Morocco . It can occur all year round. With strong southerly winds (. B. at z Scirocco ) of dust over can France and Italy as far as Central Europe arrive. If rain occurs at the same time , the rainwater turns dirty yellow-red and goes down as so-called " blood rain ". This name was used mainly in the Middle Ages and in the early modern period.
background
Such an event occurred on February 21, 2004, when dust from North Africa reached Germany. This could be observed in Munich as a gray-brown cloud. In the Alps the snow turned reddish; a similar phenomenon as the "blood rain" is thus also the "blood snow". The sand wind arose from a cold front in the west wind zone, which extended to the southern edge of the Sahara and was visible as a closed band of clouds. Within the cold front there was a strong pressure difference that led to violent wind movements that caused dust turbulence. The dust rose to great heights and was transported north. He reached the Alps and southern Germany via the Mediterranean. A triggering factor for sand transport is the intensive agricultural use and overgrazing of the steppe areas in the Sahel region of North Africa. This leads to increasing desertification and increased dust and sand transport by the wind. In the spring of 2014 and in the spring of 2018 there were also such sand transports, the effects of which reached as far as northern and western Germany.
See also
Web links
- Sahel on wetteronline.de, accessed on February 28, 2016
Individual evidence
- ↑ Elizabeth Reisp: A touch of "Sahara" is in the air. In: St.Galler Tagblatt. February 21, 2014, accessed February 28, 2016 .
- ↑ Michaela Schwegler: Small encyclopedia of omens and miracles. CH Beck. Munich 2004, ISBN 978-3-406-51078-6 , s. Pp. 12-13.
- ↑ Munich covered by Saharan dust overnight. In: Die Welt Online. February 19, 2014, accessed February 28, 2016 .
- ↑ Dieter Jäkel: Observations on the dynamics and the causes of sand and dust storms in arid areas, employed in North Africa and China. In: The Earth. 135. 2004, No. 3–4, pp. 341–367, Chapter: 3. Sand and dust storms due to global wind systems…. ( Memento of February 28, 2016 in the Internet Archive ) (PDF, p. 18 ff.) Retrieved on April 24, 2019.
- ↑ South wind brings desert greetings - Sahara dust clouds the sky. WetterOnline, April 2, 2014, accessed on February 28, 2016 .