Nitrogen dioxide pollution, averaged yearly from 2005-2011, has decreased across the United States.
Image: NASA Goddard's Scientific Visualization Studio/T. Schindler
NASA satellite images released this week in animated GIF form show how air pollution has decreased across the United States over the past decade.
"After ten years in orbit, the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite has been in orbit sufficiently long to show that people in major U.S. cities are breathing less nitrogen dioxide – a yellow-brown gas that can cause respiratory problems."
After ten years in orbit, the Ozone Monitoring Instrument (OMI) on NASA's Aura satellite has been in orbit sufficiently long to show that people in major U.S. cities are breathing less nitrogen dioxide – a yellow-brown gas that can cause respiratory problems.Nitrogen dioxide is one of the six common pollutants regulated by the U.S. Environmental Protection Agency (EPA) to protect human health. Alone it can impact the respiratory system, but it also contributes to the formation of other pollutants including ground-level ozone and particulates, which also carry adverse health effects. The gas is produced primarily during the combustion of gasoline in vehicle engines and coal in power plants. It's also a good proxy for the presence of air pollution in general.
Air pollution has decreased even though population and the number of cars on the roads have increased. The shift is the result of regulations, technology improvements and economic changes, scientists say.
But the EPA says about 142 million Americans still live in areas with unhealthy air pollution levels, and satellite imaging shows that air pollution remains a major problem in many other parts of the world.
Read more at NASA.gov, where they also offer interactive views of the data, and HD video.
