Cover Story: China’s Economic Revival Threatens Clean Air Gains

China’s decade-long battle against air pollution is facing a setback, as people witnessed a return of the choking smog that had been rarely seen in recent years.

The clear blue sky, once a rare sight, is again becoming a luxury this spring as factories gear up production in a bid to recover from three years of pandemic disruptions. In March, 14 days of heavy pollution were recorded in Beijing, and the number of days with good air quality decreased 25% from the previous year, according to official Air Quality Index (AQI) data. The concentration of PM2.5 — ultrafine particles in the air that are hazardous to health — surged 40%.