What is the Problem?

 

          What is Ozone?

Ozone is composed of three Oxygen atoms, and is unstable (2).  The formation of Ozone has been taking place for many millions of years (6) and its stability is attributed to Nitrogen compounds in the atmosphere.

 

In the Stratosphere, Ozone protects the Earth.

In the Troposphere, Ozone is dangerous.

http://www.ucar.edu/learn/1_5_1.htm

Picture of Atomic oxygen, Diatomic oxygen, and Ozone.

http://www.ucar.edu/learn/1_5_1.htm

 

          Ozone forms in the atmosphere by the action of sunlight on oxygen (6).  Ozone higher up in the atmosphere protects life on Earth (2). Ozone lower in the atmosphere (troposphere) can be toxic and a pollutant (2).

 

          Recognition of the Problem

          In the 1970s huge loss of Ozone over Antarctica was noticed by the British Antarctica Survey (5).  In 1973 Chlorine was discovered to be a major cause of Ozone depletion (1).  The process by which the Ozone depletes is that Oxygen is removed from the Ozone and leaves Chlorine unaffected (1).  When the Chlorine is left in the Ozone, it basically destroys it, leaving holes for UV-B rays to pass through.  Without Ozone, there is a potential for skin cancer and cataracts (6).  Damage to crops and to plankton and the marine food web is also present without Ozone (6).  When crops are decreased and plant life as well, carbon dioxide increases and Global Warming is a product of the Ozone thinning out (6).

 

Picture of a research station similar to that in Halley Bay, Antarctica.

In the Springtime, the Ozone thins out and weather satellites indicated that the overall percentage of ozone in the Antarctica is declining (6).

Further studies by balloons and satellites showed that the percentage of Ozone is declining as well.

http://www.atm.ch.cam.ac.uk/tour/part1.html

The Earth’s Atmosphere

http://www.atm.ch.cam.ac.uk/tour/part1.html

 

The World Meteorological Organization observed a 45 percent depletion of the ozone layer over one-third of the northern hemisphere, from Greenland to western Siberia, for several days during the winter of 1995-1996. The deficiency was believed to have been caused by chlorine and bromine compounds combined with polar stratospheric clouds formed under unusually low temperatures.” (6)

 

          With the problem evident, action was taken to preserve the Ozone.

          In 1987, the Montreal Protocol was signed and ratified by 36 countries (6).  It aimed to reduce CFCs (Chlorofluorocarbons) by half by the year 2000 (5).  The European Community had stricter measurements taken, aiming to halt all production by 1995 (5).

 

          Chlorofluorocarbons

          Chlorofluorocarbons were developed in the 1930s (1).  Its primary uses were for industrial, commercial, and household appliances (1). CFCs are non-toxic, non-flammable, and non-reactive with other compounds, and were first invented to replace dangerous Sulfur Dioxide and Ammonia refrigerants (1). Most CFCs do not dissolve in water, therefore reach the atmosphere (4).

 

Human-made halocarbons are the biggest reason for Chlorine in the atmosphere (4).

http://www-personal.umich.edu/~jlenobel/HumanActivity.html

When released into the atmosphere, CFCs rise and are broken down by sunlight (6).

The Chlorine molecules interact with Ozone and destroy it (6).

Misconceptions about the Ozone Layer:

The Ozone gets confused with Global Warming (5).

The ozone problem is not global warming, ,but because Carbon Dioxide is released into the atmosphere due to the killing of plants by radiation, , Global warming does occur.

 

          Sources

 

-         -         1. http://www-personal.umich.edu/~jlenobel/ Ozone Depletion

-         -         2. http://www-personal.umich.edu/~dparsly/oz-background%201.html Location, Size, and Concentration of the Ozone Layer

-         -         3. http://www.urbanclimate.org/ozone/Ozone_Formation.qt The Ozone Clip

-         -         4. http://www-personal.umich.edu/~jlenobel/HumanActivity.html Human Activity vs. Nature

-         -         5. http://www.atm.ch.cam.ac.uk/tour/part1.html The Ozone Hole Tour: Part One…The History of the Ozone Layer

     -    -        6. http://encarta.msn.com/find/Concise.asp?z=1&pg=2&ti=761555692 Encarta Online, Ozone Layer

 

 Next: Evidence >

Ozone Depletion Home