Chapter 05
What's actually working.
Four broad categories cover almost all of it, and each one calls for a different fix.
You
What one person can do
- Carpool, bike, walk, or take the bus when you can, U.S. transit riders keep about 63 million metric tons of CO₂ out of the air every year.
- Swap in LED bulbs and pick energy-efficient appliances the next time something dies.
- Don't idle. Ten seconds of idling burns more gas than turning the engine off and on again.
- Check your local air quality on airnow.gov, and stay inside on days it's bad, especially if you have asthma.
Tech
Where the technology is going
- Electric vehicles made up 18% of new car sales worldwide in 2024. A decade ago that number was under 1%.
- Solar and wind are now the cheapest way to build new electricity in most of the world, cheaper than coal or gas.
- Cheap home sensors from companies like PurpleAir and IQAir let regular neighborhoods track their own air quality in real time.
- Switching homes off gas, stoves, furnaces, water heaters, is quietly cutting the NO₂ people breathe indoors.
Policy
What governments have actually done
- Since 1970, the U.S. Clean Air Act has cut the six main pollutants by 78%, while the economy grew 285%. It's one of the most successful laws in American history.
- London's congestion charge dropped NO₂ in the city center by about 30%.
- The 2022 Inflation Reduction Act put $370 billion behind clean energy, the biggest climate investment the U.S. has ever made.
- In 2021 the WHO tightened its recommended PM2.5 limit by half, based on newer health research.