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 is a polar map of permafrost extent in the Northern Hemisphere. A sidebar explains how permafrost, as it forms and later thaws, serves as both a sink and source for carbon to the atmosphere. Related multimedia is a slideshow of permafrost scientists from U. of Alaska, Fairbanks, collecting permafrost data in the field.

In this visualization students can explore North American fossil fuel CO2 emissions at very fine space and time scales. The data is provided by the Vulcan emissions data project, a NASA/DOE funded effort under the North American Carbon Program (NACP).

This interactive follows carbon as it moves through various components of the carbon cycle.

With this carbon/temperature interactive model, students investigate the role of atmospheric carbon in the greenhouse effect using a relationship between atmospheric carbon dioxide and global temperature.

In this activity, students learn how carbon cycles through the Earth system by playing an online game.

In this lab activity, students use a chemical indicator (bromothymol blue) to detect the presence of carbon dioxide in animal and plant respiration and in the burning of fossil fuels and its absence in the products of plant photosynthesis. After completing the five parts of this activity, students compare the colors of the chemical indicator in each part and interpret the results in terms of the qualitative importance of carbon sinks and sources.

In this activity, students use a spreadsheet to calculate the net carbon sequestration in a set of trees; they will utilize an allometric approach based upon parameters measured on the individual trees. They determine the species of trees in the set, measure trunk diameter at a particular height, and use the spreadsheet to calculate carbon content of the tree using forestry research data.

This PBS video shows how Klaus Lackner, a geophysicist at Columbia University, is trying to tackle the problem of rising atmospheric CO2 levels by using an idea inspired by his daughter's 8th-grade science fair project.

This well-designed experiment compares CO2 impacts on salt water and fresh water. In a short demonstration, students examine how distilled water (i.e., pure water without any dissolved ions or compounds) and seawater are affected differently by increasing carbon dioxide in the air.