How beijing controlled air pollution

Beijing’s air improved markedly after 2013 through a package of policies known as the Air Pollution Prevention and Control Action Plan (APPCAP) and subsequent local measures. 

Key actions included: cutting coal use (coaltogas conversions, closing small coal boilers), upgrading industrial emission standards, relocating or retrofitting heavy industry, tighter vehicle emissions and fuel standards, and regional joint controls with surrounding provinces. 

Independent evaluations show PM2.5 fell from ~89.5 μg/m³ (2013) to ~58 μg/m³ (2017), exceeding the official 2017 target (≤60 μg/m³). Scientific attribution studies conclude that emission reductions (rather than weather) were the dominant driver of the improvement. For exams, list these measures and quote the PM2.5 decline with the years and target to demonstrate evidencebased understanding.