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Dust storms

Dust storms are common on the great grassland of North America, in the Gobi Desert of Mongolia, China, and the Sahara Desert of northern Africa. Extreme dust storms can reduce visibility to zero, making travel impossible. The dust picked up in such a storm can be carried thousands of kilometers. The huge amounts of dust blowing across the Earth may have serious consequences for the environment. The dust can affect human health, coral reefs and climate change. Dust storms transport large amounts of material for long distances, for example from the Sahara to Greenland and from China to Europe, which can cause problems far from the dust’s source.

Also, it can carry large amounts of dust, with the leading edge being composed of a wall of thick dust as much as 1.6 km (0.99 mi) high. Dust and sand storms which come off the Sahara Desert are locally known as a simoom or simoon (sîmūm, sîmūn). The haboob (həbūb) is a sandstorm prevalent in the region of Sudan around Khartoum, with occurrences being most common in the summer.

1. What can influence the dust storm?

2. The sandstorm Haboob is common in

3. The dust storm in Sudan mainly happens in the

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