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While hurricanes and tornadoes plague America and snowstorms periodically bury Europe, encroaching sand is the natural disaster shared by the band of nations lying across the Sahara, not just Mauritania, but Mali, Niger and the southern edges of Libya, Algeria and Egypt. Although the people of the desert have long battled the dunes, global climate change has made the sand more unpredictable.
Surface temperatures have risen by 0.7 degrees Celsius over the last century which has resulted in a decrease in rainfall, said Patrick Gonzalez, a climate scientist on the U.N.'s Intergovernmental Panel on Climate Change. A fifth less falls today than it did in the 1950s. Without water, there is no moisture to keep the sand in clumps. It moves freely, dissipating in a yellow mist. "It's a vicious cycle, brought on by the changes in our climate and worsened by the actions of mankind," said Moustapha Ould Mohamed, who heads the National Research Center on Desertification.
Although it is now illegal to cut much of the vegetation, desert dwellers refuse to live without some plants — for example a shrub called "alfa," commonly used by masons as roof insulation. Those living here say that at night in spite of the ban on the cutting of the shrub, they often see the silhouettes of loaded donkeys tiptoeing into town, their gait uneven under the weight of desert plant.
In a 109-page national action plan written by the Ministry of the Environment last year, the Mauritanian government proposed a series of measures from the creation of a green belt around threatened cities to projects meant to stabilize the dunes by planting sticks in formations designed to halt the flow of sand. Although the proposed plan was commissioned by the government, it's so far received no funding in Mauritania's current budget. It's an omission that underscores the country's inability to grasp the threat, said Mounkaila Goumandakoye, the acting director of the U.N. Development Program's Drylands Development Center. "What's happening in Mauritania is dramatic," he said. "Politicians are used to doing things to improve their country's GDP. They haven't yet understood the link between the advance of the dunes and their economic health."
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http://www.iht.com/articles/ap/2007/04/05/africa/AF-FEA-GEN-Mauritania-Disappearing-Country.php