Chapter 2. Chapter 2: Science Literacy and the Process of Science

This Infographic presents evidence that CFCs in the stratosphere have depleted the natural ozone layer, particularly over Antarctica. Refer back to Infographic 2.5: Is this evidence based on an experimental or observational study (or both)? How do you know?

Refer back to Infographic 2.3. What do you predict the scientists who discovered the relationship between the ozone hole and CFC levels did first with their discovery? What would scientists studying the ozone hole have done if their hypothesis was not supported? Propose another hypothesis for how the ozone hole could have formed that does not involve CFCs.

The graph in Infographic 2.7 (above) has two lines: one for atmospheric ozone level and one for atmospheric CFC concentration. Are these two concentrations measured in the same units? How can you tell? What is/are the unit(s) of concentration?

Ozone concentration is actually represented by two different lines: one connecting a point for each year that is overlaid by a smooth curve. Why do you think that ozone level was represented in two ways?

Ozone levels in the early 2000s were higher than levels in the 1990s, but the widest seasonal opening of the Antarctic ozone hole was in 2006. Propose a hypothesis to explain this fact.

Would you expect the ozone hole to be smaller or larger in 2009? Why?