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 simulation allows students to explore the change in sea surface pH levels with increasing CO2 levels.

This well-designed experiment compares CO2 impacts on salt water and fresh water. In a short demonstration, students examine how distilled water (i.e., pure water without any dissolved ions or compounds) and seawater are affected differently by increasing carbon dioxide in the air.

This NASA animation depicts thermohaline circulation in the ocean and how it relates to salinity and water density. It illustrates the sinking of water in the cold, dense ocean near Iceland and Greenland. The surface of the ocean then fades away and the animation pulls back to show the global thermohaline circulation system.

This set of activities is about carbon sources, sinks, and fluxes among them - both with and without anthropogenic components.

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 15-panel interactive from NOVA Online describes some of the factors (e.g., Earth's rotation and the sun's uneven heating of Earth's surface) contributing to the formation of the high-speed eastward flows of the jet streams, found near the top of the troposphere. These jet streams play a major role in guiding weather systems.

This activity involves plotting and comparing monthly data on atmospheric C02 concentrations over two years, as recorded in Mauna Loa and the South Pole, and postulating reasons for differences in their seasonal patterns. Longer-term data is then examined for both sites to see if seasonal variations from one site to the other carry over into longer term trends.

Coral Reefs in Hot Water is a short video displaying computerized data collected on the number of reefs impacted by coral bleaching around the world.

This short animated video provides a general overview of the role of carbon dioxide in supporting the Greenhouse Effect.