Chinese Yellow Dust

South Korea closed schools on Monday and its factories producing memory chips stepped up safeguards, as a choking pall of sand mixed with toxic dust from China covered most of the country and other parts of Asia.

The annual "yellow dust" spring storms, which originate in China's Gobi Desert before sweeping south to envelop the Korean peninsula and parts of Japan, are blamed for scores of deaths and billions of dollars in damage every year in South Korea.