New | Shanghai grinds to a halt as smog nears top of air pollution scale
Flights scrapped, roads closed and construction stopped as pollution hits east and south; no relief expected until Sunday at the earliest
Shanghai experienced one of its worst episodes of air pollution on Friday, with the air quality index reaching the "severe" level, the worst on a six-tier national rating system.
In the Pudong district, home to multinational businesses and financial services companies, the level of PM2.5 - fine particles smaller than 2.5 microns in diameter which pose the biggest health risk - exceeded 600 micrograms per cubic metre by 1pm. In Putuo district, the level exceeded 700 mcg per cubic metre. The World Health Organisation safe limit is 25 mcg per cubic metre.
Overall air quality was considerably worse than the municipal government had anticipated on Thursday when the bad pollution began. It had forecast the index would be at 240 to 310 on Friday afternoon.
With such a high concentration of air pollutants, the authorities warned even healthy people would show some serious health symptoms and be more vulnerable to disease.
Children, the elderly and the sick were advised to remain at home, while others were told to reduce their outdoor activities as much as possible.
Some of the worst polluting factories were told to limit or stop production. Building and road construction work was halted and nearly a third of government cars were pulled out of service.
Most inbound flights were cancelled and more than 50 flights diverted at Shanghai Pudong International Airport. With some roads closed, traffic was also severely affected.
A cold front arrived in the Yangtze River Delta region on Thursday but was too weak to blow air pollutants out to sea. The wind only brought more pollutants into the region and extended the smog to the south.
Much of eastern and southern China was now shrouded in pollution, the National Meteorological Centre said.
The worst hit areas are Jiangsu, Zhejiang and Anhui. Visibility in Yunnan, Fujian, Jiangxi and Hunan was cut to 500 metres.
Beijing had blue skies over the last couple of days but also woke up to smoggy weather on Friday morning, with the PM2.5 level exceeding 240 by 4pm in the southern part of the city, according to the Ministry of Environmental Protection.
The situation will not improve until Sunday, according to official forecasts. The pollutants will disperse early next week as a strong cold front reaches the Delta and drives air pollutants out towards ocean waters.
China's neighbours, such as South Korea and Japan, are likely to complain about the effect of pollution on them. Environment officials from the Seoul city government will arrive in Beijing next Wednesday. They are expected to urge China to begin sharing air pollution information with them.
