Yes, global warming continues to be a daunting time-ticking bomb. However, there’s some good news! Nitrogen levels have been shown to have decreased significantly in the USA since 1990. NASA credits the improvement in air quality to improved fuel efficiency in cars and “technology to reduce emissions of nitrogen dioxide and sulfur dioxide from coal-fired power plants.”
2005 was the beginning of satellite imaging specifically aimed towards monitoring pollution, the images collected show an impressive decline in nitrogen levels in the past decade. This decline in nitrogen levels can be traced to 1990, which is the same year that saw the 1990 Clean Air Act Amendments pass into law. The images being cited were produced by data collected from the Ozone Monitoring Instrument on NASA’s Aura satellite. They show a dramatic decline in nitrogen levels and can be viewed by clicking HERE.
The Clean Air Act was aimed towards coal power plants, requiring these main pollution culprits to clean up their nitrogen-thick process. Coal power plants have been retrofitted with flue-gas desulfurization (FGD), or scrubbers, and many coal plants have switched to lower sulfur coal. In 2005, EPA developed the Clean Air Interstate Rule, a cap-and-trade program intended to further reduce SO2 and Nitrogen emissions, working to limit emissions beyond the levels defined by the acid rain program in the eastern half of the United States. Precautions have proven their worth, showing a more-than-50% decline in Nitrogen levels.
According to EPA, the most concentrated areas of nitrogen are near power plants or roadways. Individuals living near high concentrations of Nitrogen report more frequently to the Hospitals for breathing complications. Cases of asthma tend to develop and can aggravate existing heart disease, in susceptible individuals complications can lead to increased hospital admissions and premature death. Nitrogen dioxide can cause respiratory problems by itself, besides also reacting with “ammonia, moisture, and other compounds to form small particles,” or particles, that can worsen emphysema and other lung ailments, the EPA noted. Nitrogen gas also contributes to the formation of ozone, which is an irritant and pollutant at ground level. We can all breath a little easier knowing that nitrogen levels are on the decrease.
“While our air quality has certainly improved over the last few decades, there is still work to do–ozone and particulate matter are still problems,” NASA atmospheric scientist Bryan Duncan said. NASA has also cited that 142 million people still live in areas in the United States with unhealthy levels of air pollution.