A video from the Extreme Ice Survey in which Dr. Tad Pfeffer and photographer Jim Balog discuss the dynamics of the Columbia glacier's retreat in recent years through this time-lapse movie. Key point: glacier size is being reduced not just by glacial melting but due to a shift in glacial dynamics brought on by climate change.

This is a series of 5 guided-inquiry activities that examine data and models that climate scientists use to attempt to answer the question of Earth's future climate.

This video provides a good overview of ice-albedo feedback. Albedo-Climate feedback is a positive feedback that builds student understanding of climate change.

This video provides an overview of changes happening in the Arctic.

In this video segment, a team of scientists seeks evidence to support their hypothesis that atmospheric warming may cause water to form beneath the West Antarctic ice sheet. This water causes ice streams to flow much more quickly than the rest of the ice sheet, which has important implications for sea level rise.

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 multi-part activity introduces users to normal seasonal sea surface temperature (SST) variation as well as extreme variation, as in the case of El NiÃo and La NiÃa events, in the equatorial Pacific Ocean. Via a THREDDS server, users learn how to download seasonal SST data for the years 1982 to 1998. Using a geographic information system (GIS), they visualize and analyze that data, looking for the tell-tale SST signature of El NiÃo and La NiÃa events that occurred during that time period. At the end, students analyze a season of their own choosing to determine if an El NiÃo or La NiÃa SST pattern emerged in that year's data.

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 is the seventh of nine lessons in the 'Visualizing and Understanding the Science of Climate Change' website. This lesson addresses climate feedback loops and how these loops help drive and regulate Earth's unique climate system.

In this activity, students explore past examples of climate variability in three locations: the Peruvian and Bolivian Andes, Central America, and coastal Greenland, and consider differences between climate variability and climate change.