Why blue skies over Beijing this winter could herald a turning point in city's battle against pollution

Why blue skies over Beijing this winter could herald a turning point in city's battle against pollution
- including Chengdu in the southwestern province of Sichuan and urban parts of the Yangtze Delta, such as Shanghai – had suffered air pollution at the same time that residents in Beijing were enjoying the blue skies. This suggests it will still be a huge challenge for China to ...