READ: Ozone Case Study

Explore this Phenomenon

  • What are your observations about what has happened in this photo?
  • What questions do you have about what has happened here?
  • How do you explain what is happening?


Conserving Natural Resources

Natural resources must be conserved and protected so that people in developed nations maintain a good lifestyle and people in developing nations have the ability to improve their lifestyles. To do this, people are researching ways to find renewable alternatives to non-renewable resources.

Below is one example of a way that people have tried to solve a problem that resulted from of our use of resources. They recognized the problem, proposed a way to mitigate the negative effects, and monitored the results.

Case Study: Healing the Ozone Layer

What’s destroying the ozone layer? When ozone is in the upper atmosphere it protects our planet from dangerous radiation from the sun. Most ozone loss it taking place over the South Pole and Antarctica. This is the location of the ozone hole. The ozone hole is a region in the   stratosphere where there is less ozone than normal. (See figure.) The ozone layer is also thinner over the Northern Hemisphere.

The main cause of the hole in the ozone is chlorofluorocarbons (CFCs). Scientists discovered that these human-made chemicals destroy ozone molecules in the upper atmosphere. In the past, CFCs were widely used in spray cans, refrigerators, and many other products.

  

Effects of Ozone Loss

With less ozone in the stratosphere, more UV rays reach the ground. More UV rays increase skin  cancer  rates. Just a 1 percent loss of ozone causes a 5 percent increase in skin cancer. More UV rays also harm plants and phytoplankton. As a result, they produce less food. This may affect entire  ecosystems.

Protecting the Ozone Layer

The Montreal Protocol is a worldwide agreement on   air pollution. It was put into place after people realized the problem with CFC’s  The Protocol focuses on limiting the use of CFCs. It was signed by many countries in 1987 and it controls almost 100 chemicals that can damage the ozone layer. Its goal was to return the ozone layer to its previous state.

Ozone Recovery

The Montreal Protocol has been effective in controlling CFCs. By 1995, few CFCs were still being used. But the ozone hole kept growing for several years after that because of the CFCs already in the atmosphere. It peaked in 2006. Since then, the situation has improved. The Montreal Protocol is a shining example of how nations can come together to solve a global environmental problem. The 2006 ozone hole was the largest on record. The holes are beginning to get a bit smaller; the 2012 and 2013 holes were relatively small.

Putting It All Together

  • How has your understanding changed?
  • Can you think of another phenomenon that applies these concepts?.
  • Explain what is going on based on what you have learned in this section.
  •  What ideas do you have about how to solve this problem?


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Last modified: Tuesday, 27 June 2017, 3:04 PM