This NASA video discusses the impacts of the sun's energy, Earth's reflectance and greenhouse gases on the Earth System.

This short video from Climate Central explains the technology used to monitor changes in Arctic sea ice. Long-term tracking (since the late 1970's) shows Arctic sea ice has been on a steady decline and this could have significant implications for global temperatures.

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.

In this video, students learn that scientific evidence strongly suggests that different regions on Earth do not respond equally to increased temperatures. Ice-covered regions appear to be particularly sensitive to even small changes in global temperature. This video segment adapted from NASA's Goddard Space Flight Center details how global warming may already be responsible for a significant reduction in glacial ice, which may in turn have significant consequences for the planet.

In this video segment, a team of scientists seeks evidence to support their hypothesis that atmospheric warming -- either now or in the past -- may explain why water has formed beneath the West Antarctic ice sheet, causing ice streams that flow much more quickly than the rest of the ice sheet. This phenomenon has important implications for potential sea level rise.

This is a polar map of permafrost extent in the Northern Hemisphere. A sidebar explains how permafrost, as it forms and later thaws, serves as both a sink and source for carbon to the atmosphere. Related multimedia is a slideshow of permafrost scientists from U. of Alaska, Fairbanks, collecting permafrost data in the field.

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 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 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.

This video examines how scientists learn about the effects of climate change on the water cycle and what those effects might mean for our planet.

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