This short video illustrates the phenomena of El NiÃo and La NiÃa: their relationships to tradewinds and surface water temperatures, and their effects on precipitation in North America.

This animation demonstrates the changing declination of the sun with a time-lapse animation. It shows how the shadow of a building changes over the course of a year as the declination of the sun changes.

This NASA animation presents the levels of atmospheric carbon dioxide over the last 400,000 years, last 1000 years and last 25 years at different time scales. 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 video highlights research conducted at Woods Hole on how heat absorbed by the ocean and changes of ocean chemistry from human activities could lead to a tipping point for marine life and ecosystems. Includes ice bath experiment that models the tipping point of Arctic sea ice.

This straightforward calculator provides conversions from one unit of energy to the equivalent amount of CO2 emission expected from using that amount.

This video features research conducted at University of Colorado's Institute of Arctic and Alpine Research, which studies isotopes of hydrogen trapped in ice cores to understand climate changes in the past.

In this learning activity, students use a web-based geologic timeline to examine temperature, CO2 concentration, and ice cover data to investigate how climate has changed during the last 715 million years.

This video features residents of Shishmaref, Alaska, plus environmental journalist Elizabeth Kolbert and scientist John Holdren, exploring the human impacts of global climate change.

In this video, adapted from KUAC-TV and the Geophysical Institute at the University of Alaska, Fairbanks, viewers learn how one-celled organisms in permafrost may be contributing to greenhouse gas levels and global warming.

The Climate Momentum Simulation allows users to quickly compare the resulting sea level rise, temperature change, atmospheric CO2, and global CO2 emissions from six different policy options projected out to 2100.

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