HEAVY smog in Shanghai this morning is the result of pollutants blown from the north. However, stronger southeast winds in the afternoon will help bring an end to the latest wave of haze and pollution affecting the city, the Shanghai Environmental Protection Bureau said.
This morning will see moderate to heavy pollution, with PM2.5 the major constituent, but the bureau expects good air quality by the afternoon, becoming excellent at night.
Air quality will also be good during the day tomorrow, but another wave of haze and heavy pollution is predicted to arrive at night and stay around on Monday, the bureau said.
This next wave of pollution could be stronger, last longer and affect more areas, it warned.
The city issued its first blue alert for air pollution yesterday, just two days after it lowered thresholds on its pollution alarm system.
The alert came at 11am, recommending that children, the elderly and people suffering from chronic diseases, especially of the heart and lungs, stay indoors.
The pollution had been swept in on a cold front from the north and the lack of wind contributed to the problem, weather authorities said. The air quality index was above the 200 mark from 7am to noon yesterday, when it began to drop, reaching 162, or moderate pollution, at 4pm, the environmental bureau said.
Under the revised alert system, a blue alert is triggered when the AQI is between 151 and 200 and short periods of heavy pollution (over 201) are expected in the next 24 hours.
Previously, the blue alarm was activated when the air quality was forecast to be between 201 and 300 over the following 24 hours.
Today should be sunny to cloudy, with temperatures ranging from 3 to 12 degrees Celsius.
Tomorrow the range will be 9 to 17 degrees when it will be overcast with some drizzle. Fog is also forecast for some areas in the morning.
Monday will be cloudy, with a high of 17 degrees but dropping to as low as 11 degrees, the weather bureau said.
Source: AFP
