C-Learn is a simplified version of the C-ROADS simulator. Its primary purpose is to help users understand the long-term climate effects (CO2 concentrations, global temperature, sea level rise) of various customized actions to reduce fossil fuel CO2 emissions, reduce deforestation, and grow more trees. Students can ask multiple, customized what-if questions and understand why the system reacts as it does.

Bell Telephone Science Hour produced this video in 1958, explaining how the production of CO2 from factories and automobiles is causing the atmosphere to warm, melting the polar ice caps, and causing the sea level to rise.