Page 26 - 新思维科学活动用书9 样章

1.4 Climate change

5 Look at graph C.
Most scientists think that human activities are contributing to the changes in carbon dioxide

concentration shown in the graph.

Use your own knowledge to explain why they think this.

6 Look at graph C again.

The measurements of carbon dioxide concentration were made in Hawaii, which is in the
northern hemisphere.

Thinking about plants and photosynthesis, suggest why the line wiggles up and down (varies
throughout) each year.

25