Why is the air cleaner now than 30 years ago?

Air quality has improved over the past 30 years due to stricter environmental regulations, advancements in technology, and a shift towards cleaner energy sources. Governments have implemented policies to reduce emissions from industries and vehicles, leading to lower levels of pollutants such as sulfur dioxide and nitrogen oxides. Additionally, the rise of renewable energy and electric vehicles has contributed to decreasing reliance on fossil fuels, further enhancing air quality. Public awareness and advocacy for cleaner air have also played a significant role in driving these positive changes.