The ozone molecule is made up of three oxygen atoms making it O3, just one more oxygen atom than an oxygen molecule (O2). Although it is made up of oxygen atoms; ozone molecules are very unstable and will easily bind to other atoms. Ozone molecules can be found in the stratosphere and troposphere layers of the atmosphere. However, the majority of ozone is found in the stratosphere between 10 and 30 miles above the earth's surface. .
The ozone layer was originally created by early organisms called blue-green algae. This algae lived in the ocean and used energy from the sun to split the H2O from the water and the CO2 in the air to make oxygen. This process is more commonly known as photosynthesis. The oxygen molecules then went into the air where they absorbed UV rays and split into atoms. The atoms attached to preexisting oxygen molecules to create ozone. Before ozone life could only be found in the ocean but the ozone layer allowed organisms to develop and evolve until they could live on land.
All around us we hear about the holes in the ozone layer, but at the same time we hear about scientist worried about having too much ozone. How is that possible? Ozone molecules do different things depending where it is, the upper or lower atmosphere. In the lower atmosphere, or the troposphere, ozone molecules wreak havoc on people with different ailments, mainly those with respiratory illnesses. It is also responsible for the majority of photochemical smog. Ozone in the troposphere is produced by a mixture of sunlight, oxygen, and car exhaust causing photochemical smog to be more present in urban areas.
While the ozone in the troposphere is increasing ozone in the upper atmosphere, the stratosphere, is declining. This bad for us because ozone creates a shield around the Earth that protects from ultraviolet rays that the sun puts off. These ultraviolet rays, if we were not protected, would literally roast us.
