Satellite image of a dust storm from the Sahara desert hitting the Canary Islands

NASA Goddard Space Flight Center

Research shows that dust storms are increasing in certain parts of the world, including China and Africa's Sahara desert. The latest estimates put global dust emissions at about 2,000-3,000 million tonnes each year. In parts of North Africa, annual dust production has increased tenfold in the last 50 years.

Dust storms transport large amounts of material for long distances and their increasing frequency could have serious consequences for the environment, according to Andrew Goudie of the University of Oxford. Goudie says the deposition of dust could affect climate change, disease transmission and air pollution. One concern is that as dust deposits increase, levels of carbon dioxide in the atmosphere could change, directly affecting temperatures and rainfall.

Using satellite imagery, scientists are able to monitor dust storms and have now identified the world's primary dust source to be the Bodele depression in Chad. Drought, winds, increased grazing and deforestation all contribute to dust production.

Link to full BBC Online news story