This short video, adapted from NOVA, explains how Earth's position relative to the Sun might be responsible for the dramatic shift in the climate of what is now the Saharan nation of Djibouti.

This animated slideshow introduces biodiesel as a fuel alternative. With concern about the use of petroleum-based fuels at an all-time high, biodiesel is experiencing a popularity surge. And algaeâotherwise known to some as pond scumâ are grabbing headlines as the next potential biodiesel superstar. But how and why do algae make oil? And why do they make so much of it? In this audio slide show, U.C. Berkeley's Kris Niyogi describes the process and its potential.

This is a collection of five short videos that show how climate change is affecting fishing, native populations and access for the oil and gas industry in the Arctic. The videos include personal reflections by writers Andrew C. Revkin and Simon Romero, scientists, and residents about their experience of the impacts of the climate change in the Arctic.

In this short video, atmospheric scientist Scott Denning gives a candid and entertaining explanation of how greenhouse gases in Earth's atmosphere warm our planet.

This video focuses on the conifer forest in Alaska to explore the carbon cycle and how the forest responds to rising atmospheric carbon dioxide. Topics addressed in the video include wildfires, reflectivity, and the role of permafrost in the global carbon cycle.

This article and slide show from the New York Times, features several scientists from the University of Alaska, Fairbanks, who study the effects of thawing permafrost in Alaska.

This short video, the sixth in the National Academies Climate Change, Lines of Evidence series, explores the hypothesis that changes in solar energy output may be responsible for observed global surface temperature rise. Several lines of evidence, such as direct satellite observations, are reviewed.

This image depicts a representative subset of the atmospheric processes related to aerosol lifecycles, cloud lifecycles, and aerosol-cloud-precipitation interactions that must be understood to improve future climate predictions.

This NASA video provides a nice overview of Earth's water cycle from the perspective of looking at Earth from space.

This PBS video shows how Klaus Lackner, a geophysicist at Columbia University, is trying to tackle the problem of rising atmospheric CO2 levels by using an idea inspired by his daughter's 8th-grade science fair project. The video examines the idea of pulling CO2 out of the atmosphere via a passive chemical process.

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