After a record-breaking sandstorm on Monday and blue skies on Tuesday, dusky yellow skies returned to Beijing and Tianjin Wednesday morning as a strong south wind swept the dust back into the city, causing air pollution to soar again. The pollution is expected to last until Friday, according to forecasts.
The north wind first blew dust from the north to south, and then a stronger south wind brought the dust back, causing a reflux, experts explained. The sand and dust, which had been expected to flow to southern China, were now less likely to arrive there.
The primary pollutant in the air is PM10. Children, the elderly and patients with heart or lung diseases are advised to stay indoors, and the general population should reduce outdoor exercise, the city said.
On Monday morning, the capital city was engulfed by the largest sandstorm in a decade, which originated in Mongolia. Previous forecasts said that the sand and dust would gradually move southward and possibly affect Central China and the Yangtze River Delta region.
But the sand and dust, which just left the city on Tuesday, returned from the southwest in the afternoon, causing a sharp increase in the PM10 concentration in Beijing and Tianjin, the BJMEMC said on Wednesday morning.
The situation is expected to turn better on Friday as a new round of strong cold air sweeps the northern part of China from northwest to southeast, and rain falls in some areas.