Sunday, November 26, 2017

What is Ozone?

You have been living a dangerous life on daily basis without even realizing it. You inhale polluted air mixed with your friend’s bad breath, eat hamburgers cooked by a chef with dandruff problems on his mustache, drive under the influence of heavy metal music, and wear thongs while exercising. It all sounds very dangerous, but they are nothing compared to UV radiation from the sun; either that or the lack of Internet connection. While one the most common causes of a disconnected Internet is the fact that you forget to pay the bill, UV radiation is a persistent risk of living preventable only by the existence of Ozone layer.

What is Ozone
Ozone is somewhere around and circling the Earth, definitely
Before you begin to care deeply about life on Earth, you must understand what Ozone actually is. You have probably come across the term before from watching TV which you do very often or reading a book which on the other hand is a genuine rarity.

Earth is the most habitable planet in the solar system because of two major reasons:
  • The planet provides useful stuffs that all living creatures need such as air, carbon, water, and terrestrial television. It does not give you money, but you can earn revenues by selling photographs of the Earth to NASA and Garmin.
  • Everything on Earth is well-insulated by atmosphere, so the temperature on the surface is neither too cold nor too warm. Some places are indeed extremely cold but it is not impossible for human to live there, albeit temporarily. For more information on this, feel free to visit the North Pole.
Atmosphere does three main functions: it keeps the Earth’s surface warm enough, provides oxygen, and protects everything beneath it from UV radiation generated by the sun. Major portions of the atmosphere are comprised of nitrogen and oxygen or the air you breathe. Both gases, however, cannot retain heat but fortunately the atmosphere also has what it takes to do the job; it is called greenhouse gases which include carbon dioxide, nitrous oxide, water vapor, methane, and ozone. Too much of those cause something that everybody calls global warming.
Ozone is one of greenhouse gases, which retains heat, but it multitasks as a protective layer to block ultraviolet radiation. Unless you skip chemistry class far too often to find Pokemon, you should know that the chemical formula for Ozone is O3 so it consists of three Oxygen atoms. Based on that definition, Ozone is actually just a special form of Oxygen.

Where is Ozone?

Earth’s atmosphere has 6 layers and is comprised of 78% nitrogen, 21% oxygen; the remaining 1% consists of many things which may include water vapor, dust particles, bacteria from your mouth, and everything that comes out of cars’ exhaust pipes. Both troposphere (the lowest atmospheric layer) and stratosphere (the second lowest atmospheric layer) have ozone.

In the stratosphere, Ozone is formed when an Oxygen molecule (O2) is broken apart by ultraviolet radiation; the result is two Oxygen atoms that no longer bind together. Each of the atoms is highly reactive and actively seeking for new partners. Every time an atom successfully binds an Oxygen molecule, Ozone is produced. Ozone does protect Earth from harmful UV radiation, but it forms thanks to the radiation in the first place. The process is pretty much like a divorce, but without the subpoena and custody issues.

In the troposphere, chemical reactions which primarily involve pollutant gases from fossil fuel combustion can also produce ozone. Sunlight is required to complete the process. As soon as tropospheric ozone reacts with surfaces of plants or soil, however, they are destroyed.

How Does Ozone Block UV Radiation?

In many scientific books for children, you will read that Ozone blocks UV radiations. This is neither entirely wrong nor totally accurate. Don’t blame the book – the writer is still smarter than you. What really protects you from getting sunburn and immune system suppression due to UV radiation is the relentless Ozone-Oxygen production cycle that happens in three stages:
  1. When UV light reaches the stratosphere, it reacts with Oxygen molecule (O2) and breaks the bond. The separation of Oxygen molecule into two Oxygen atoms consumes the energy generated by the UV light.
  2. The resulting two Oxygen atoms bind themselves with two Oxygen molecules. These reactions produce two Ozone molecules.
  3. The remaining energy generated by UV light is then utilized to break down O3.
As all three stages are completed, UV light only has about 2% of energy that reaches Earth’s surface. In other words, the Ozone helps eliminate the dangerous effects of harmful radiation by 98%. It is worth mentioning that only the short-wavelength UV light is affected by Ozone. Long-wavelength radiations do reach the Earth but they are much less harmful than their shorter counterparts.