Thursday, May 1, 2014

How can we fix the ozone layer?

You asked a very interesting question about ozone and how can we fix the ozone layer.

It is true that lightning creates ozone. Any spark in air will do it. Ozone can also be created by certain forms of radiation. Ozone is a molecule of oxygen that consists of three atoms instead of the usual two. It has peculiar chemical properties, it is highly reactive, and at ground level it can be toxic to people and contribute to health hazards like smog.

Unfortunately, the ozone created by lightning is all in Earth's troposphere, below about 50,000 feet, the part of our atmosphere where weather happens and life flourishes. Fortunately, although thunderstorms are constantly happening all across Earth's surface, they don't create enough ozone to be much of a problem.

The ozone layer that protects organisms on the surface from ultraviolet radiation is in the stratosphere, above 50,000 feet. Here there is good and bad news, too. Ozone is created when oxygen absorbs the energy of ultraviolet light. So UV light makes ozone, and ozone absorbs even more UV light. Nature itself can take care of us, if we don't mess it up too much. That is the bad news. Some chemicals we have added to the atmosphere over many years react with ozone and break up the molecules. We have stopped using many of the nastiest ozone depleters but they break down very slowly and continue to destroy ozone. Eventually, we hope, these chemicals will wear out, and the stratosphere will be back to the way it once was, more or less. Human activity still continues, and we have to make intelligent decisions about risks.

While I was researching my answer, I found two interesting websites. http://www.weatherquestions.com/What_is_the_ozone_layer.htm has basic information about the ozone layer, and http://www2.epa.gov/sunwise/uv-index has an up-to-date ozone weather map.