If you wanted to live where the chances of a destructive earthquake were small, would you pick a location near a fault zone, near a mid ocean ridge, near a subduction zone, or on a volcanic island such as Hawaii? What are the relative risks of earthquakes at each of these locations?
Which type of object would likely cause more damage if it struck near an urban area: a small metallic object or a large stony/icy one?
If all life were destroyed on Earth by a large impact, would new life eventually form to take its place? Explain how conditions would have to change for life to start again on our planet.
Why is a decrease in Earth’s ozone harmful to life?
Why are we concerned about the increases in CO2 and other gases that cause the greenhouse effect in Earth’s atmosphere? What steps can we take in the future to reduce the levels of CO2 in our atmosphere? What factors stand in the way of taking the steps you suggest? (You may include technological, economic, and political factors in your answer.)
Do you think scientists should make plans to defend Earth from future asteroid impacts? Is it right to intervene in the same evolutionary process that made the development of mammals (including us) possible after the big impact 65 million years ago?