Establish Prior Knowledge
Call on students to share what they know about coral reefs. If necessary, direct them to this web site:http://www.amnh.org/exhibitions/permanent/ocean/02_ecosystems/index.php
Discuss with students why coral reefs are essential in maintaining diversity in the oceans. Tell students that in the Snapshot they are about to see marine biologists at Australia’s Great Barrier Reef document the growth of coral.
Have students read the synopsis and view the Snapshot. Use the following questions to guide a class discussion.
1. How do marine biologists measure the growth rate of Porite coral?
2. What evidence do they have that, since 1990, the growth of Porite coral has slowed?
3. What do marine biologists suspect is causing this slow growth?
4. What is causing the oceans to be warmer and less mineral-rich?
Discuss with students the impact climate change will have on coral reefs and on ocean life if these trends continue.