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. Last Updated: 07/27/2016

Chinese Deserts Sweep Into S. Korea

SEOUL, South Korea -- School was called off throughout much of this sprawling city last Monday because of inclement weather.

It was not a freak spring snowstorm, a heat wave or torrential rains.

Rather, it was an immense cloud of dust that blew in from China's fast-spreading deserts, about 1,200 kilometers away.

It hid Seoul from view throughout the morning, obscuring the sunrise just as surely as the heaviest of fogs. Clinics overflowed with patients complaining of breathing problems, drugstores experienced a run on cough medicines and face masks that supposedly filter the air, and parks and outdoor malls were nearly empty of pedestrians.

With the arrival of the huge dust storms for the third consecutive year, Koreans have begun to grimly resign themselves to the addition of an unwelcome fifth season -- already dubbed the season of yellow dust -- to the usual four seasons of a temperate country.

Like the harmattan in West Africa, when skies turn a soupy gray for weeks at a time because of seasonal wind patterns that bring airborne dust southward from the Sahara, Korea's new season is a disturbing reminder for Asians of global interconnectedness and the perils of environmental degradation.

"There is no way for us to deter this,'' said Kim Seung-bae, deputy director of South Korea's national weather service. "All we can do is try to forecast the yellow dust storms as early as possible, but with the current technology we can only detect it one day ahead of time at best. For now, our main innovation will be to add predictions of the intensity of the dust to our weather reports.'"

In Seoul, a measurement of 70 micrograms of dust per cubic meter of air is considered normal for most of the year. At 1,000 micrograms, experts say, serious health warnings are needed. Last week, in the fourth storm of the season, a record measurement of 2,070 micrograms was reached in this city. Kim said two or three more storms could hit Korea this month.

Scientists say the dust storms, which are distinctly visible on regional satellite weather maps as gigantic yellow blobs, are the result of the rapid desertification in China and a prolonged drought affecting that country and other parts of northeast Asia. The term "yellow dust'' refers to the color of the sand when it coats parked cars and windows rather than the color of the skies, which all last week were a thick, acrid gray.

According to China's Environmental Protection Agency, the Gobi desert grew by 52,000 square kilometers between 1994 and 1999, and its steadily advancing edge is now only 240 kilometers north of Beijing. As in West Africa, which weather experts say is the world's leading source of dust, environmental changes in China are accelerating because of overfarming, overgrazing and the widespread destruction of forests.

But unlike West Africa's dust, which is carried to the southern United States by winds known as the tropical easterlies, dust from the Gobi and Taklimakan deserts in rapidly industrializing China is binding with toxic industrial pollutants, including arsenic, cadmium and lead, increasing the health threat.

Changes like these have long made springtime synonymous with respiratory distress in Beijing. But as the dust storms have grown, their impact has been spreading rapidly eastward, blighting the air over the Korean peninsula and beyond.