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

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

This peer-reviewed educational video explains human-caused climate change including the greenhouse effect. The role that greenhouse gases play in absorbing and re-emitting longwave radiation is illustrated. Information on how scientists know that the observed global warming is a result of human activities that burn fossil fuels is concisely explained.

Here students use data from the NOAA carbon dioxide monitoring sites, such as Mauna Loa, to graph the Keeling Curve for themselves on large sheets of paper. Each group graphs one year, and the graphs are joined at the end to reveal the overall upward trend. The explanation describes the carbon cycle and how human activities are leading to the overall trend of rising carbon dioxide.