Increased smog this year the result of 'unfavorable meteorological conditions'

The country has experienced an uptick in heavy air pollution this year, despite generally consistent air quality improvement, according to the Ministry of Ecology and Environment.

The average density of PM2.5 particulate matter in the 339 major cities across the country stood at 55 micrograms per cubic meter in January, decreasing by 1 mcg per cubic m from the same period last year, the ministry said in a media release on Monday.

If transformed into days on a 24-hour basis, it said, the cumulative time with fairly good air quality — considered to be below 100 on the 0-500 air quality index scale — in these cities covered 74.3 percent of the calendar days, up by 0.9 percentage points year-on-year.

The cumulative time with heavy air pollution, however, covered 5.4 percent of the calendar days, up by 2.3 percentage points, it added.

In total, it said, such heavily smoggy time was equivalent to 564 days, up by 239 days from the same period last year.

Unfavorable meteorological conditions, the use of fireworks during the seven-day Spring Festival holiday, which started this year on Jan 21, and comparatively more frequent dusty weather events were to blame for the situation, the ministry said.

Many regions were engulfed by a heavy air pollution event around New Year's Day, which dwarfed all others in the past three years in terms of severity, duration and the stretch of affected areas, it said.

The emissions of major air pollutants, which remain at high levels, are the root cause for the event that lasted from Dec 27 to Jan 13, it said.

Metrological conditions, which featured low wind speed and high humidity and were unfavorable for the dispersal of air pollutants, made the situation even worse.

It said the country's major cities experienced a total of 76 days with heavy haze caused by the use of fireworks during the Spring Festival holiday.

In January, dusty weather events made these major cities suffer heavy air pollution in 77 days, 76 more compared with the same month last year, it continued.

The ministry said it has changed its way of notifying air quality in major cities, in a move to urge local authorities to intensify air pollution control and facilitate public supervision over the work.

More information concerning heavy air pollution, for instance, has been included in the notification, it said.

According to a 2021 guideline on enhancing air pollution control from the central authorities, China aims to decrease the proportion of cumulative days with heavy air pollution to below 1 percent by 2025.

The country has experienced continuous improvement in its air quality in the past decade.

The average density of PM 2.5 particulate matter in Beijing, for example, reached 30 mcg per cubic m last year, decreasing by almost 60 mcg per cubic m from 2013, the first year when PM 2.5 was monitored in the capital.