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Testing the hypothesis of ozone depletion (3 of 3)

Image Caption

Chlorine monoxide is one of the products of ozone destruction. Since there is no other known source of chlorine monoxide, finding this chemical in the upper atmosphere would strongly support the idea that chlorine is destroying ozone.

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Top row with phrases in green bubbles correspond to image below. First column "Hypothesis/theory" with an image of an aerosol can surrounded by Ozone molecules. The next column shows “Expected results/observations” with Chlorine monoxide atom. “ Chlorine should be present in the upper atmosphere.” In the next column, we see “equal to or not equal” to “Actual results/ observations” which shows a a large question mark.

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This image is part of a series:

Top row with phrases in green bubbles correspond to image below. First column "Hypothesis/theory" with an image of an aerosol can surrounded by Ozone molecules. The next column shows “Expected results/observations” with a large question mark below it. In the next column, we see “equal to or not equal” to “Actual results/ observations” which is on top of another question mark.

Testing the hypothesis of ozone depletion (1 of 3)

Molina and Rowland needed to test their ideas with actual atmospheric evidence, but figuring out just what evidence to look for was tricky.

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Top row with phrases in green bubbles correspond to image below. First column "Hypothesis/theory" with an image of an aerosol can surrounded by Ozone molecules. The next column shows “Expected results/observations” with CFCs floating at the bottom of image. “If CFCs are destroyed in the upper atmosphere then more CFCs will be present at altitudes.” In the next column, we see “equal to or not equal” to “Actual results/ observations” which shows a graph of CFC concentration versus altitude and the trend line sharply declines.

Testing the hypothesis of ozone depletion (2 of 3)

If CFCs are destroying the ozone layer, then we would expect/predict that more CFCs will be present at lower altitudes.

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