f. The interconnectedness of Earth's systems means that a significant change in any one component of the climate system can influence the equilibrium of the entire Earth system. Positive feedback loops can amplify these effects and trigger abrupt changes in the climate system. These complex interactions may result in climate change that is more rapid and on a larger scale than projected by current climate models.

This interactive visualization from the NASA Earth Observatory website compares Arctic sea ice minimum extent from 1984 to that of 2012.

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 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.

In this activity students download satellite images displaying land surface temperature, snow cover, and reflected short wave radiation data from the NASA Earth Observation (NEO) Web site. They then explore and animate these images using the free tool ImageJ and utilize the Web-based analysis tools built into NEO to observe, graph, and analyze the relationships among these three variables.

This is a jigsaw activity in which students are assigned to research one step out of five in the geochemical process stages of the organic carbon cycle. Students then teach their step in cross-step groups until everyone understands all five process stages.

The purpose of this activity is to identify global patterns and connections in environmental data contained in the GLOBE Earth Systems Poster, to connect observations made within the Earth Systems Poster to data and information at the National Snow and Ice Data Center, and to understand the connections between solar energy and changes at the poles, including feedback related to albedo.

This interactive visualization adapted from NASA and the U.S. Geological Survey illustrates the concept of albedo, which is the measure of how much solar radiation is reflected from Earth's surface.

This animation depicts the carbon cycle in a fashion that is suited for younger audiences. The video discusses how carbon enters and exits the environment through both natural and human-driven ways.

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.

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