Although this article may seem to be basic to many people that are knowledgeable about the topic, but there are still some that really don’t know the difference. Unfortunately, some of these people are even science teachers in grade school by remote schools worldwide.
What is Ozone Depletion?
Let’s start with what is ozone?
Ozone is actually oxygen. Although the common oxygen we breath are molecules of O2. This is two atoms of oxygen bonded together by a double covalent bond, where each bond can be expressed as an electron pair. Now Ozone is actually O3, where it’s molecules are each composed of 3 atoms of Oxygen. Although this may be unusual for oxygen since oxygen atoms could only take 2 covalent bonds, and the 3 oxygen atoms in ozone are arranged in a straight line, the middle oxygen is actually having a kind of shared bond on the other two oxygen atoms. (A similar behavior of this is commonly seen in a benzene ring.) Although this can be pictured in a different way depending on the model you use, since bonds can be expressed as fixed lines, but sometimes also as electron clouds. But for the purposes of discussion, here is how it goes. As I started thinking about it, I think if I discuss it further, this post will be too long. I will make another story dedicated to ozone alone. But what is important now is just to know that ozone is also oxygen but has 3 oxygen atoms (O3) while the oxygen we breath has 2 oxygen atoms (O2).
What is the Ozone Layer? How is ozone made and how does it get destroyed? And why is it important to us?
This is nothing but a layer of ozone in out atmosphere. O3 can actually be made from O2 and O2 can make O3. Since O3 is a bit unstable, getting hit by some waves of light from the sun, mainly in the UV wavelengths, these convert O3 to O2 just by knocking out an electron by the wave making O2 and a very unstable atom oxygen. And when these other oxygen atoms hit other unpaired ones, you get O2 again. Since UV light could knockout some electrons, these are known to cause unpaired electrons from bonds which are called free radicals, and could cause cancer. Having the ozone layer in our atmosphere filters out a large amount of UV light to decrease the potential carcinogenic danger of the sun.
O3 to O2 is made simply by being exposed to the sun and O3 is quite unstable and O2 is stable thus, most of the time, you will see more abundance of O2 than O3. Now to create O3, coming from O2 requires a little more energy to consume. O2 with some electric current can produce O3, so in lightning storms O3 is created in every strike, also some can convert quickly to O2 and some will stay as O3. If you have ever experienced being near someone doing some electrical welding work, O2 near the electrical welding rod is converted to O3 and it has a very distinct odor.
How does the ozone layer deplete and does the depletion of the ozone layer contribute in GlobaWarming?
The ozone layer depletion is caused by other gases called chlorofluorocarbons or CFCs. These are still carbon based compounds in the gaseous state containing Chlorine and/or Florine. Where when they come in contact with O3, they could be converted into other compounds where atomic oxygen is separated from O3 forming O2 and this atomic oxygen is bonded with the CFCs forming other compounds, thus decreasing the amount of O3. This has been like an everyday talked about issue in the 80’s but the campaign for CFC free appliances and other devices has greatly decrease the amount of man-made CFCs. Since the ozone layer’s depletion is mainly a concern of increasing the cancer-causing UV rays from the sun, the depletion of the ozone layer does not contribute in the globalwarming from the greenhouse effect.
Generally, what is GlobalWarming?
When talking about global warming, this is generally referring to the greenhouse effect. This does not concern the depletion of the ozone layer with the increase dangers of UV rays from the sun. GlobalWarming is the overall increase of global temperature due to greenhouse gases.
Rays from the sun also include IR waves that some are partially reflected, refracted, and absorbed by greenhouse gases. Which are mainly water vapor, and other gases such as methane, carbon dioxide and others. These IR waves that get to pass through the layer of greenhouse gases that hit the surface of the earth, and bounce back to the atmosphere will hit once again the layer of greenhouse gases where some of the rays will be pushed back to earth and back to the greenhouse gases again where some amount of the IR waves are trapped in this loop and for every time these greenhouse gases bounce back IR waves, heat is generated by the greenhouse gases. Creating an overall impact of an increase in temperature worldwide.
Clearly this is a different issue from the depletion of the ozone layer. This website, GlobalWarming Awareness2007 has already a more detailed introduction story on Global Warming and the Greenhouse Effect.