Mosses exposed and analyzed
Students will answer questions about how scientists measure the age of newly thawed mosses in the Arctic, and the implications of those scientists' findings.
Educator Guide: Mosses Tell Story of Retreating Ice
ICE FREED Radiocarbon dating of mosses revealed by retreating ice on Baffin Island in Canada (shown) suggest the region has less ice cover now than it did 40,000 years ago.
Michael Studinger/NASA
About this guide
The article “Mosses tell story of retreating ice” describes how radioactive carbon-14 dating of newly exposed mosses in the Arctic shows that summers are the warmest they have been in at least the last 40,000 years. This guide covers frozen mosses, carbon-14 dating and global warming, as well as related concepts. The activity invites students to explore exponential radioactive decay and half-life with a simulation using pennies, a chemical reaction using food coloring and bleach, and through students’ own calculations. The 2016 Shattered Earth’s Heat Record Educator Guide is another great resource for teaching about environmental change.
This Guide Includes:
Uniting past and present
Students will search the Science News archive for stories related to frozen mosses, radioactive carbon-14 dating and global warming.
Making carbon connections
These discussion prompts cover the basics of radioactive decay and carbon-14 dating, as well as concepts related to climate change.
Exploring half-life
Students will simulate the exponential radioactive decay and half-life of carbon-14 with pennies and a food coloring/bleach chemical reaction.