Dust storms emanating from the Sahara have increased tenfold in 50 years, contributing to climate change as well as threatening human health and destroying coral reefs thousands of kilometers away.
And one major cause is the replacement of the camel by four-wheel drive vehicles as the desert vehicle of choice.
Andrew Goudie, geography professor at Oxford University, blames the process of Toyotarization -- a coinage reflecting the near-ubiquitous desert use of Toyota Land Cruisers -- for destroying a thin crust of lichen and stones that has protected vast areas of the Sahara from the wind for centuries.
Four-wheel drive use, along with overgrazing and deforestation, were the major causes of the world's growing dust storm problem, the scale of which was much bigger than previously realized, Goudie, master of St Cross College, told the International Geographical Congress in Glasgow, Scotland, on Thursday.
"I am quite serious, you should look at deserts from the air, scarred all over by wheel tracks, people driving indiscriminately over the surface breaking it up. Toyotarization is a major cause of dust storms. If I had my way I would ban them from driving off-road."
The problem has become so serious that an estimated 2 billion to 3 billion tonnes of dust is carried away on the wind each year. Storms in the Sahara transport dust high into the atmosphere and deposit it as far away as Greenland and the US.
The UK was seeing increasing levels of "blood rain" in spring that came direct from the Sahara, Goudie said. From an aircraft over the Alps in summer it was possible to see the telltale color of red dust on the mountains.
Although the storms are mainly particles of quartz, smaller than grains of sand, they also contain salt and quantities of pesticide and herbicide which can cause serious health problems. Microbe-laden dust from storms is also credited with carrying cattle diseases such as foot and mouth.
The world's largest single dust source is the Bodele depression in Chad, between an ever-shrinking Lake Chad (now a twentieth of its size in the 1960s) and the Sahara.
The depression releases 1.2 billion tonnes of dust a year, 10 times more than when measurements began in 1947, according to Goudie's research.
Taking the whole Sahara, and the Sahel to the south, dust volumes had increased four- to sixfold since the 1960s. Countries worst affected were Niger, Chad, northern Nigeria, Burkina Faso and Mauritania, the research found.
But the effects went far beyond. In the Caribbean, scientists had directly linked the death of coral reefs to smothering by dust which had travelled almost 5,000km.
African dust had also found its way to Greenland, Goudie said. While white ice reflected sunlight and remains frozen, the dark dust on top absorbed the sun's heat, causing the ice to melt and accelerating the raising of sea levels.
In China, extensive efforts had been made to plant trees to hold back the dust, and increases in rainfall had also helped, the study found. However, large dust storms were still emanating from the vast deserts in the north, which included the Lopnor nuclear test site -- raising fears that storms could interfere with the 2008 Olympics in Beijing and might contain radioactive particles.
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