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.

In this activity, students graph and analyze methane data, extracted from an ice core, to examine how atmospheric methane has changed over the past 109,000 years in a case study format. Calculating the rate of change of modern methane concentrations, they compare the radiative forcing of methane and carbon dioxide and make predictions about the future, based on what they have learned from the data and man's role in that future.

This National Geographic video explains the origins of the El NiÃo Southern Oscillation using animations and shows the impacts on humans, wildlife and habitat, particularly in the United States.

This simulation allows the user to project CO2 sources and sinks by adjusting the points on a graph and then running the simulation to see projections for the impact on atmospheric CO2 and global temperatures.

This Motions of the Sun Lab is an interactive applet from the University of Nebraska-Lincoln Astronomy Applet project.

This lesson covers different aspects of the major greenhouse gases - water vapor, carbon dioxide, methane, nitrous oxides and CFCs - including some of the ways in which human activities are affecting the atmospheric concentrations of these key greenhouse gases. This is lesson six in a nine-lesson module about climate change.

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.

This narrated slide presentation shows the carbon cycle. It looks at various parts of this biogeochemical sequence by examining carbon reservoirs and how carbon is exchanged among them.

This interactive activity, in applet form, guides students through the motion of the sun and how they relate to seasons.

This article and slide show from the New York Times, features several scientists from the University of Alaska, Fairbanks, who study the effects of thawing permafrost in Alaska.