This article and included graphs,from the web site accompanying the FRONTLINE NOVA special What's Up with the Weather?, reveals how atmospheric carbon dioxide, methane, and nitrous oxides from coal- and oil-burning power plants, cars, and other fossil-fuel-burning sources have climbed along with the world population, with as yet unknown effects on the climate system.
This site is a searchable encyclopedia of thousands of photos, descriptions, sound recordings, and other information about individual animal species. Find out about amphibians, arthropods, birds, fishes, insects, mammals, mollusks, reptiles, and sharks. Explore special features on mammals, skulls, and frog calls. Students are invited to contribute.
A learning module on photosynthesis enhanced with colorful graphics, questions for review, and additional links.