Environment

The Guardian - San Francisco cut levels of two key air pollutants by more than 20% between 2010 and 2024. It was the only US city that reduced levels of nitrogen dioxide (NO₂) and fine particulate pollution (PM2.5) by more than 20%, according to an analysis of nearly 100 cities around the world. Beijing and London were also among the 19 global cities to have achieved “remarkable reductions” in air pollution – notably, nearly half of the leading cities were in Central and east Asia.