Synopsis:

The polar regions are home to the fastest warming on the planet. Warming releases not only carbon dioxide but also methane – an even stronger greenhouse gas. Will more warming release more of these gases, leading to more warming in a dangerous feedback loop

Find the article:

Photo: K. W. Anthony, NASA

A researcher watches burning methane. He lit the fire, but bacteria below the lake made the methane as they decomposed organic matter. Could large releases of Arctic methane disturb the climate?

Discussion Questions

1. Discuss positive and negative feedback. Use warming ==> methane release ==> more warming as the example of positive feedback. Use more wolves ==> fewer deer ==> fewer wolves for negative feedback. Ask class for other examples and discuss. Point out that positive feedback can tend to spiral out of control, while negative feedback tends to bring the situation back toward its starting point.
2. Discuss the decision by Edward Schuur to use a survey of experts instead of concentrating on published studies. What reasons did he cite for his decision? Is the strategy risky? Ask the class to list advantages and disadvantages.
3. Discuss this sentence: “The tricky thing with the feedback problem is that you end up caring about the interactions between all the feedbacks,” says Charles Koven, whether they are related to clouds, radiation, the carbon cycle or changes in forests or permafrost.” Is the abundance of unknowns a reason to avoid action about climate change? Or does feedback raise the stakes and the urgency of preventive action? Some compare the expense of reducing greenhouse warming to buying fire insurance on a house: How much money do we want to spend to insure against an uncertain peril?

Lesson Plans/Activities

1. Internet research: Explore the above-ground effects of melting permafrost, on transportation, buildings, utilities and industrial infrastructure, such as the oil industry.
2. Ask students to distill the argument about the “methane burp” in the East Siberian Sea. What is the threat, and how certain is it? What is one reason why the “burp” may be more likely than skeptics think?
3. Internet research: Collect 1 photo and a write short description of taiga and tundra in the Arctic and sub-Arctic regions.