This video examines the thawing of permafrost due to changes in climate and shows examples of the impacts that warming temperatures have on permafrost in the Arctic, including the release of the greenhouse gas methane. Dramatic results are shown, including sink holes forming on the landscape and beneath buildings, roads, and other infrastructure, causing some communities to relocate.

In this video, a PhD Student from the University of Maine explains how ice cores are used to study global climate change.

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.

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 static graph of changes in CO2 concentrations is going 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 NASA animation depicts thermohaline circulation in the ocean and how it relates to salinity and water density. It illustrates the sinking of water in the cold, dense ocean near Iceland and Greenland. The surface of the ocean then fades away and the animation pulls back to show the global thermohaline circulation system.

This video describes how the normal thousands-of-years-long balance of new ice creation and melting due to ocean currents has been disrupted recently by warmer ocean currents. As a result, glacier tongues that overhang the interface between ice and ocean are breaking off and falling into the ocean.

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 Nino and La Nina 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.

This is a video that documents the reflections of members of the Steger International Polar Expedition team reunited at the 25th anniversary of their landmark trek to the Arctic, and how climate change has made their trek difficult to replicate.

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