This is a sequence of 5 classroom activities focusing on the El NiÃo climate variability. The activities increase in complexity and student-directedness. The focus of the activities is on accessing and manipulating real data to help students understand El NiÃo as an interaction of Earth systems.

This straightforward calculator provides conversions from one unit of energy to the equivalent amount of CO2 emission expected from using that amount.

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.

In this activity, students compare carbon dioxide data from Mauna Loa Observatory, Barrow, Alaska, and the South Pole over the past 40 years. Students use the data to learn about what causes short-term and long-term changes in atmospheric carbon dioxide. This activity makes extensive use of Excel.

In this activity, students use the GLOBE Student Data Archive and visualizations to explore changes in regional and seasonal temperature patterns.

In this video, Michael Mann and Peter Ramsdorf explore some of the information from the 2013 IPCC 5th report in light of public perceptions of climate science.

This video illustrates how atmospheric particles, or aerosols (such as black carbon, sulfates, dust, fog), can affect the energy balance of Earth regionally, and the implications for surface temperature warming and cooling.

This activity uses two interactive simulations to illustrate climate change, 1) at the micro/molecular level - modeling the impact of increasing concentrations of greenhouse gases in the atmosphere on surface temperature and 2) at the macro level - modeling changes in glacier thickness and flow as a result of rising surface temperature.

This video segment, from the 'Earth: The Operators' Manual' featuring climate expert Richard Alley, shows how ice cores stored at the National Ice Core Lab provide evidence that ancient ice contains records of Earth's past climate - specifically carbon dioxide and temperature.

This short video, is the fifth in the National Academies Climate Change, Lines of Evidence series. It focuses on greenhouse gases, climate forcing (natural and human-caused), and global energy balance.