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.

In this activity, students explore the role of combustion in the carbon cycle. They learn that carbon flows among reservoirs on Earth through processes such as respiration, photosynthesis, combustion, and decomposition, and that combustion of fossil fuels is causing an imbalance. This activity is one in a series of 9 activities.

This is a short experiment to demonstrate the concept of thermal expansion of water when heated, as an analogy to thermal expansion of oceans due to global warming.

In this hands-on lesson, students measure the effect of distance and inclination on the amount of heat felt by an object and apply this experiment to building an understanding of seasonality. In Part 1, the students set up two thermometers at different distances from a light bulb and record their temperatures to determine how distance from a heat source affects temperature. In Part 2, students construct a device designed to measure the temperature as a function of viewing angle toward the Sun by placing a thermometer inside a black construction paper sleeve, and placing the device at different angles toward the Sun. They then explain how distance and inclination affect heat and identify situations where these concepts apply, such as the seasons on Earth and the NASA Mercury MESSENGER mission.

This interactive shows the extent of the killing of lodgepole pine trees in western Canada. The spread of pine beetle throughout British Columbia has devastated the lodgepole pine forests there. This animation shows the spread of the beetle and the increasing numbers of trees affected from 1999-2008 and predicts the spread up until 2015.

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.

This video describes what black carbon is, where is comes from, and how it contributes to sea ice melt and global warming.

In this video from the Polaris Project Website, American and Siberian university students describe their research on permafrost.

In this experiment, students investigate the importance of carbon dioxide to the reproductive growth of a marine microalga, Dunalliela sp. (Note that the directions are for teachers and that students protocol sheets will need to be created by teachers.)

In this activity, students collect weather data over several days or weeks, graph temperature data, and compare the temperature data collected with long-term climate averages from where they live. Understanding the difference between weather and climate and interpreting local weather data are important first steps to understanding larger-scale global climate changes.

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