Heavy smog expected to put chokehold on northern cities, stick around until midweek

Beijing residents got a brief respite from a spate of smog on Sunday morning, when the chilly air went from hazardous to good. But the pollution will come back stronger on Monday and engulf the capital and its southern neighbors again for three days, the national weather authority said.

Beijing saw readings of PM2.5 - hazardous particulate matter with a diameter less than 2.5 microns - drop dramatically from 106 micrograms per cubic meter on Saturday evening to 24 by 8 am. on Sunday, according to the Beijing Municipal Environment Monitoring Center. It started creeping back up and was at 64 by 4 pm. The cutoff for "good" air is 75.

Wind once again carried away the airborne gunk after a week of heavy-pollution days, the center said.

Liu Jiangbo, 29, could finally run for 5 kilometers near his community on Sunday morning.

"It's quite cold, but I have stayed indoors for a week due to the severe pollution and urgently need to exercise," he said.

Like Liu, Li Xinying, 45, was happy about the clean air as she walked around in a park for an hour. During heavy smog, she usually walks in her living room, which she finds too constraining.

Northern China, including Tianjin and Hebei province, generally saw improvement in air quality on Sunday, following Beijing's pattern from severe to good. But central regions such as cities in Shanxi, Henan and Jiangsu provinces were still blanketed by heavy smog on Sunday.

The Central Meteorological Administration said wind is expected to fade, and heavy smog will cover Beijing, Tianjin and Hebei province once again beginning on Sunday night.

Air quality will climb back to severe quickly, the observatory said, adding that in some cities it would reach the most hazardous level.

The new spell is expected to last until Wednesday, it said.

China's vast northern regions have experienced several spells of severe smog since November. Beijing has twice issued a red alert - the highest emergency response.

Of northern China's 70 cities, 25 saw pollution hit the top two most severe levels on Saturday, the Ministry of Environmental Protection said.

"It's frustrating to wait for wind to disperse the pollution, which has been the only effective way for us to breathe healthily and walk outdoors," said Wang Ying, a 32-year-old mother of two in Beijing.