After reporting its best winter air quality for five years in December, Beijing said on Friday it is gearing up for its first major smog of the year.
Heavy pollution is set to engulf the Chinese capital and the neighbouring region – comprising the provinces of Hebei, Shanxi, Shandong and Henan, and the port city of Tianjin – from today until Wednesday, the China National Environmental Monitoring Centre said.
An orange smog alert, the second-highest in a four-tier system, will come into effect in Beijing on Saturday and remain in place until Monday, the municipal environmental protection bureau said.
Under the terms of the city’s air pollution emergency response plan, an orange alert is issued when the average air quality index is forecast to surpass 200 for three consecutive days and 300 on at least one of those days.
The move also means that all construction work in the capital will be suspended and construction vehicles will be banned from the city’s streets.
The bureau advised children and the elderly to remain indoors during the period, and recommended the use of face masks for anyone who could not avoid venturing outside.
The skies over Beijing’s central business district appeared relatively clear at lunchtime on Friday, although by 1pm, the official AQI reading stood at 102, putting it in the “unhealthy” range.
On social media, people were quick to respond to the news that the poor air had returned to the city.
“Smog is supposed to be the normal weather in Beijing, should we clap?” a person wrote on Weibo, the Chinese equivalent of Twitter.
“Without wind, the air quality just suddenly worsens,” another said.
“To think that a media outlet asked just yesterday whether we can keep the blue skies throughout the year. And now, the smog is coming back again,” a third person said.
The orange alert comes just two weeks after Beijing reported that a combination of favourable weather and tough air pollution controls had resulted in the city seeing its best winter air quality in half a decade.
Authorities recorded a run of 25 consecutive days in December on which the air quality was rated “excellent” or “good”. On the rare days that smog did appear, it dispersed more quickly and was less severe, with levels of PM2.5 – the tiny, breathable particles that pose a risk to people’s health – never surpassing 300 micrograms per cubic metre.
A report by the global environmental watchdog Greenpeace this week said levels of PM2.5 in Beijing, Tianjin and 26 surrounding cities fell by more than 33 per cent year on year in the final three months of last year as the government shut down factories and sent inspectors to enforce strict environmental regulations.
Beijing’s environmental bureau said earlier that air quality in 2017 was “good” or “excellent” – indicating PM2.5 levels were below 150mcg – on 60 per cent of days.