Science Visualized Environment

Ups and downs in the quest for clean air

BREATHING EASIER  Newly released maps reveal that U.S. air quality has markedly improved over the last decade.

NASA Goddard Scientific Visualization Studio

By Andrew Grant

- More than 2 years ago

Newly released maps reveal that U.S. air quality has markedly improved over the last decade. The evidence comes from measurements of nitrogen dioxide (NO2 ), a pollutant emitted by vehicles and coal power plants.