EcoBlog

Ozone is a pale blue, relatively unstable molecule made of three atoms of oxygen, represented with the chemical formula O3. It was first discovered by Christian Friedrich Schonbein, a German scientist, in 1893. Ozone molecules are angular, polar, and diamagnetic. The oxygen bond lengths are identical. Ozone is formed from molecular oxygen (O2) by ultraviolet and extreme ultraviolet photolysis and then recombination of atomic oxygen (O) with O2. It can also be formed by passing an electrical discharge through gaseous oxygen. Ozone has a unique odor that is often noticed during electrical storms and near electrical equipment.
Ozone can have vastly different effects depending on where ozone resides. At atmospheric heights of about 15 miles up, ozone acts as a shield to protect Earth’s surface from the sun’s harmful ultraviolet radiation. It this shield was not there, humans would be more vulnerable to skin cancer, cataracts, and impaired immune systems. In the air closer to Earth, that humans breathe, ozone is a harmful pollutant that can damage lung tissue and plants. Ozone is a major component of smog. Because ozone also reacts strongly with other molecules, it is dangerous to have large concentrations near the ground. Hot weather and strong sunlight cause ground-level ozone concentration levels to rise to hazardously high levels. Urban areas often have high levels of “bad� ozone.
About 90 percent of the Earth’s ozone is at higher altitudes, where it absorbs ultraviolet radiation. Wither out the shield in the stratosphere, the radiation would have an easy path to follow to strike Earth. The hole in the ozone layer is allowing this radiation a clearer shot at the Earth.
Ozone depletion occurs naturally over Antarctica because of the ice clouds formed during the winter. The ice clouds convert the chlorine to its atomic form. The air over Antarctica is the only place where it is cold enough for the reactions necessary to convert the ozone to oxygen due to the polar vortex formed by the cold polar winds. There is no hole above the North Pole because the average temperature is warmer than at the South Pole.
The polar winds keep the ozone surrounding the hole from filling in the hole, but if the winds are strong enough to keep the ozone out, why don’t they keep the hole from getting bigger? Any thoughts would be great. We hope to answer this in our next post.