3.1.2 Ozone Destruction: A Catalytic Process
Pass out materials to students. Explain that they will be using colored dots to represent chemical elements. Each student will be responsible for creating a visual display of the ozone destruction (depletion) process.
Go on-line and download maps of Antarctica showing the ozone hole since 1986.
Research the causes of ozone depletion on Earth. What's being done in the United States and internationally to slow the rate of ozone depletion?
Research NASA's TOMS (Total Ozone Mapping Spectrometer). How does it work? What data has been collected so far and what does the data indicate?
How much do you weigh?
Because humans are consumers in a food web, every kilogram of our bodies was built out of nutrients from other plants and animals. Scientists estimate that the ratio of input to resulting body mass is about 1 to 10 (1:10). This means that to make 1kg of your weight, your body required about 10 kg of nutrients. Those 10 kg were made from 10 times that amount of the next item in the food chain.
An expanding and continuing ozone hole over the Antarctic could have serious results. All life in the world's oceans depends on phytoplankton. Through the process of photosynthesis, these tiny "drifting plants" convert carbon dioxide and water (see Activity 3.2) into carbohydrates, fats and proteins. If they are destroyed by UV radiation, the entire ocean food web would be upset.
As a rough and ready example of the "multiplier effects" involved in food chains, if you'd been raised on a diet of seafood, compute the number of kilograms of inputs farther down the food chain it might have taken to reach your present weight:
Try the same exercise with a beef diet:
And with a vegetarian diet:
EPA's Stratospheric Ozone Web site: science of ozone depletion, regulations,
and many links:
NASA Ames' resource files for teachers and students, particularly middle
to high schoolers.
Includes animation of 1995 ozone hole data and links to current NOAA
NASA's Facts-Fact Sheet on Ozone from modeling to monitoring projects.
Earth Observing Systems Project at NASA, Goddard: history of TOMS (Total
Ozone Mapping Spectrometer) and live image links.
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