Estimates
have shown that dust storms blow about 11,8 millions metric tons of
desert sand from Africa to the Northeast Amazon Basin in Brazil
annually. Dust storms occur everywhere around the world. Their natural
function is replacement of soils and carrying nutrients from one part of
the globe to another. Iron
and other nutrients are blown out to sea where they maintain marine
ecosystems. Central and South American rain forests also receive vital
nutrients from Saharan dust storms.
Causes of
dust storms include droughts and poor farming and grazing practises.
Oxford University geography professor Andrew Goudie stated in 2001 that
cars driving the Sahara are another possible cause of dust storm
formation.
Dust storms have increased as a result of extensive deforestation and desertification in many regions. This has caused some countries to start forestation projects.
Sensitive or allergic people suffer from dust storms, because these carry not only nutrients but also microbes and pollens. For most people however, dust storms are mainly a nuisance because visibility is decreased and all their possessions are covered in a thick layer of dust.
Dust storms have increased as a result of extensive deforestation and desertification in many regions. This has caused some countries to start forestation projects.
Sensitive or allergic people suffer from dust storms, because these carry not only nutrients but also microbes and pollens. For most people however, dust storms are mainly a nuisance because visibility is decreased and all their possessions are covered in a thick layer of dust.
China - In 1998
a violent dust storm hit Beijing, China, darkening the skies. This was
the worst dust storm in over a decade. Dust was blown from the Gobi
Desert near Mongolia into the city. At least 12 people went missing
during the storm and power and water supplies were cut. Three Beijing
construction workers were killed when strong winds blew iron wire and
asphalt off the top of a 2-story building.Residents ran for cover in the streets, using towels to cover their faces, and the city's busy traffic ground to a halt in most areas. On the most busy roads in town visibility had decreased to only 500 meters.
Schools were closed in China, North Korea and even Russia after the dust storm started. In the capital of South Korea, Seoul, children and elderly people were advised to stay indoors to prevent breathing problems. About 35 domestic flights in Seoul were cancelled and 70 were called off before take-off.
In total, more than 100 million people were affected by the 2000 dust storm. It is said that the storm was caused by arid weather and prevailing winds, and by pasture ploughing. The government wants to try to prevent future dust storms from hitting Beijing by planting a green belt of trees around the capital.
Australia - In 2002
Queensland, Australia was hit by a violent desert storm, which shut
down regional airports and urged residents to stay indoors. Visibility
fell as low as 50 meters in regions with reduced vegetation cover. The
dust storm was at least 6 km high at Chaleville, South Queensland and
blew more than a million tonnes of dust into the region. Some claimed
this was the worst dust storm witnessed in 20 years.
It
was said the cause of the dust storm was a gusty southerly wind change
moving over Queensland. Like in Beijing, people with asthma, children
and elderly people were advised to stay inside to prevent breathing
problems. Cars were obligated to drive with dipped headlights on.
Aviation forecasters stated that many airports were closed.
Other dust storms
It
was said the cause of the dust storm was a gusty southerly wind change
moving over Queensland. Like in Beijing, people with asthma, children
and elderly people were advised to stay inside to prevent breathing
problems. Cars were obligated to drive with dipped headlights on.
Aviation forecasters stated that many airports were closed.Other dust storms
Dust
storms are fairly common. Even in Europe the results of a dust storm
can sometimes be witnessed as a small dust layer on the tops of cars.
Examples of other dust storms include:
- 1901 dust storm from the Sahara to Europe and the Ural Mountains
- 1928 dust storm from Ukraine to Romania and Poland
- 1930-1931 Dust Bowl in the Oklahoma Panhandle region, causing red snow on England and a mass exodus
- 1930 dust storms in Midwestern United States
- 2001 dust storm from Asia to the United States
- 1928 dust storm from Ukraine to Romania and Poland
- 1930-1931 Dust Bowl in the Oklahoma Panhandle region, causing red snow on England and a mass exodus
- 1930 dust storms in Midwestern United States
- 2001 dust storm from Asia to the United States
Sources
- McKinney, M.L., Schoch, R.M., Environmental Science: Systems and Solutions, Third Edition, Jones and Bartlett Publishers, Sudbury Massachusetts 2003
- Encyclopaedia: http://www.wikipedia.org
- Richter scale: http://www.seismo.unr.edu
- Arsenic poisoning: BBC News, Unesco Courier
- Tsunami Asia: http://www.giro800800.nl
- Turkey earthquakes: http://www.earthquakes.bgs.ac.uk/turkey_nov99.htm
- Flood: http://www.bibliotheek.nl
- Volcanic eruptions: various websites
- Wildfires: Daniela Hart, Brazilian Wildfires Threaten Indians, The Washington Post March 1998 and FOA organization, South American Region Fire Assessment, 2003
- Tornadoes: http://www.tornadoproject.com
- Dust storms: BBC News, Herald Sun, MSNBC, New York Times
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