This NASA animation shows the levels of atmospheric carbon dioxide over different time scales. Viewers can compare the last 400,000 years, last 1000 years, and last 25 years. The data come from the Lake Vostok ice cores (400,000 BC to about 4000 BC), Law Dome ice cores (1010 AD to 1975 AD) and Mauna Loa observations (1980 to 2005).

This static graph of changes in CO2 concentrations goes back 400,000 years, showing the dramatic spike in recent years.

This video shows 15 years of data obtained via Polar-orbiting satellites that are able to detect subtle differences in ocean color, allowing scientists to see where there are higher concentrations of phytoplankton - a proxy for the concentration of chlorophyll in the ocean.

This video provides a simple introduction to wind turbines and how they generate electricity.

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 short video shows how humanity uses energy today; what sources we use; and why, in the future, a growing global population will require more energy.

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.

This video reviews how photovoltaic (PV) cells work, noting that technological innovations are decreasing costs and allowing PV use to expand.

An interactive simulation of Earth's seasonal dynamics that includes the axial tilt and other aspects of Earth's annual cycle.

This is part of a larger lab from the University of Nebraska at Lincoln: http://astro.unl.edu/naap/motion1/motion1.html

This carbon calculator, developed by the EPA, guides students in calculating their carbon footprint and then using that information to make decisions about how to reduce their carbon emissions.

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