NASA satellite data shows the air we breathe is getting cleaner.
Airborne pollutants can negatively affect our health. Such molecules can flow from city to city via wind, building a river of smog as evident around our nation’s Northeast Corridor and over flatter terrain in the eastern U.S. One major air pollutant is nitrogen dioxide, a brownish gas commonly emitted from motor vehicle exhaust and power plants. This noxious chemical causes respiratory issues and promotes the formation of other harmful air pollutants like ground-level ozone. Observations by the Ozone Monitoring Instrument aboard NASA’s Aura satellite show that nitrogen dioxide levels have actually decreased nationwide by four percent per year since 2005. The decline is thought to stem partly from technology improvements, especially in the energy and transportation sectors. Watch the video to see changes in nitrogen dioxide levels across the U.S. from 2005 to 2011.