This video segment from 'Earth: The Operators' Manual' explores how we know that today's increased levels of CO2 are caused by humans burning fossil fuels and not by some natural process, such as volcanic out-gassing. Climate scientist Richard Alley provides a detailed step-by-step explanation that examines the physics and chemistry of different "flavors," or isotopes, of carbon in Earth's atmosphere.

This NASA animation on land cover change zooms into Rondonia, Brazil. It starts with a Landsat satellite image taken in 1975 and dissolves into a second image of the same region taken in 2009 that illustrates a significant amount of land use change.

A sequence of five short animated videos that explain the properties of carbon in relationship to global warming, narrated by Robert Krulwich from NPR.

This activity illustrates the carbon cycle using an age-appropriate hook, and it includes thorough discussion and hands-on experimentation. Students learn about the geological (ancient) carbon cycle; they investigate the role of dinosaurs in the carbon cycle, and the eventual storage of carbon in the form of chalk. Students discover how the carbon cycle has been occurring for millions of years and is necessary for life on Earth. Finally, they may extend their knowledge to the concept of global warming and how engineers are working to understand the carbon cycle and reduce harmful carbon dioxide emissions.

This static graph of changes in CO2 concentrations goes back 400,000 years, showing the dramatic spike in recent years.

This short video describes the Hestia project - a software tool and data model that provide visualizations of localized CO2 emissions from residential, commercial, and vehicle levels, as well as day versus night comparisons, in the city of Indianapolis.

This video highlights the work of climate scientists in the Amazon who research the relationship between deforestation, construction of new dams, and increased amounts of greenhouse gases being exchanged between the biosphere and the atmosphere.

In this activity, students explore the way that human activities have changed the way that carbon is distributed in Earth's atmosphere, lithosphere, biosphere and hydrosphere.

This set of activities is about carbon sources, sinks, and fluxes among them - both with and without anthropogenic components.

This activity describes the flow of carbon in the environment and focuses on how much carbon is stored in trees. It goes on to have students analyze data and make calculations about the amount of carbon stored in a set of trees at three sites in a wooded area that were to be cut down to build a college dormitory.