In this audio slideshow, an ecologist from the University of Florida describes the radiocarbon dating technique that scientists use to determine the amount of carbon within the permafrost of the Arctic tundra. Understanding the rate of carbon released as permafrost thaws is necessary to understand how this positive feedback mechanism is contributing to climate change that may further increase global surface temperatures.

This activity has students examine the misconception that there is no scientific consensus on climate change. Students explore temperature data and report their conclusions to the class. Then students examine techniques of science denial and examine a claim about scientific consensus.