Ozone Sources: Natural or Man-Made?

Investigation of this issue came from a recent conversation with a friend, Joe Mastromatteo, who is always looking for ways to help advance the Dimidia cause.

Today, it was about lightning and ozone.

I was able to identify two NASA related studies that provide an interesting profile in ozone formation. I found both in issues of Innovations Report, a Forum for Science, Industry and Business. However, the original findings were published in the American Geophysical Union's Journal of Geophysical Research Atmospheres.

The first article - Satellites See Lightning Strikes in Ozone's Origin (07/2003) - offers a very interesting description of how collaborators from NCAR (National Center for Atmospheric Research), Canada and Europe, using several different NASA and ESA (European Space Agency) satellites and a computer model from NCAR were able to determine the origin of low-level ozone pollution and whether the sources were man-made or natural. There are a couple of good graphics as well.

The article is very interesting. I will only provide one discovery and hope you will read the entire article.

• Fires create smoke and carbon monoxide. Lightning creates nitrogen oxides. All of these come together with other unstable compounds in a chemical soup. Sunlight helps trigger the reaction that helps form ozone!

The second article - Study Shows Lightning Adds to Ozone Level (03/2003) - provides even more insight into the impact of lightning worldwide. Here are a couple of facts from that report.

• There is strong evidence that urban air pollution may contribute to more lightning, creating more ozone over the United States.
• Nitrogen oxides can lead to the formation of ozone and smog and these can greatly increase chemical reactions in the atmosphere.

How much lightning is out there each year? 77 million lightning bolts strike the US each year. Worldwide, lightning flashes occur about 60 times per second!

I guess nature is as good at creating atmospheric pollutants as are humans.