Chinese capital declares major victory against air pollution

The Beijing Municipal Ecology and Environment Bureau announced on Sunday that 2025 recorded just one day affected by heavy air pollution, a staggering reduction of approximately 98.3 percent from the 58 days recorded in 2013.

Under China's national Air Quality Index (AQI) system, air quality is classified into several levels ranging from "excellent" to "severe pollution." "Heavy pollution" refers to days with an AQI between 201 and 300, which generally corresponds to 24-hour average PM2.5 concentrations of about 150 to 300 micrograms per cubic meter, according to national standards used by environmental and meteorological authorities.

This indicates that heavily polluted days have been essentially eliminated in the Chinese capital, according to the bureau.

In a landmark achievement, the city's annual average concentration of PM2.5, a key indicator of air pollution, in 2025 stood at 27.0 micrograms per cubic meter, marking the first time it has fallen below the 30-microgram benchmark since monitoring began.

Historically, Beijing grappled with severe and frequent smog. Back in 2013, its annual average PM2.5 concentration reached 89.5 micrograms per cubic meter. Atmospheric pollution was once a prominent problem that constrained urban development and affected public well-being.

Confronted with this critical challenge, Beijing launched an unprecedented "blue sky defense war," according to the bureau.