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

The NOAA Ocean Service Education lab requires students create and manipulate solutions simulating different ocean water characteristics in order to recognize that the effects of salinity and temperature are the drivers of thermohaline circulation.

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 lab activity, students use a chemical indicator (bromothymol blue) to detect the presence of carbon dioxide in animal and plant respiration and in the burning of fossil fuels and its absence in the products of plant photosynthesis. After completing the five parts of this activity, students compare the colors of the chemical indicator in each part and interpret the results in terms of the qualitative importance of carbon sinks and sources.

This video segment features subsistence fishing and harvesting in the Northwestern US. The segment was adapted from a student video produced at Northwest Indian College in Bellingham, Washington.

Students explore their own Ecological Footprint in the context of how many Earths it would take if everyone used the same amount of resources they did. They compare this to the Ecological Footprint of individuals in other parts of the world and to the Ecological footprint of a family member when they were the student's age.

This animation shows the Arctic sea ice September (minimum) extents from 1979-2014.

This short video is an excerpt from the longer video Acid Test: The Global Challenge of Ocean Acidification, produced by the National Resources Defense Council (NRDC). This short version summarizes the science of ocean acidification as well as the social implications.

This video is one of a series produced by the Switch Energy project. It reviews the pros and cons of natural gas as a source of energy.

This Motions of the Sun Lab is an interactive applet from the University of Nebraska-Lincoln Astronomy Applet project.