Northern China's spring sandstorms blew in with particular ferocity over the weekend, bringing misery to people working outdoors Monday in Beijing and across a wide swath of the country. "It gets in your throat, under your clothes, in your bed," said Beijing street sweeper Xue Yuan. "I hate it, but there's really nothing you can do."
The storms are a product of worsening desertification in Inner Mongolia and other Gobi Desert regions hundreds of miles to the north and west of Beijing caused by overgrazing, deforestation, drought and urban sprawl. Strong winds pick up the loose dust and dirt, mixing them with industrial pollution.
Beijing's air quality index was set at Level 4, one grade better than the most serious Level 5 that was reached Saturday as the mixture of sand, dust and pollution blasted the capital. City meteorologists said conditions would improve, but warned the sand would linger through midweek.
Record pollution levels were registered in Hong Kong, 1,240 miles (2,000 kilometers) to the south, partly due to the storms. Schools were advised to cancel outdoor activities and at least 20 elderly people sought medical assistance for shortness of breath, Hong Kong's radio RTHK reported.
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http://www.washingtonpost.com/wp-dyn/content/article/2010/03/22/AR2010032200676.html