Global warming is an increase in the average temperature of the Earth's lower atmosphere. Since the Industrial Revolution, that temperature has gone up by an average of 1.1 degrees Fahrenheit.
Encyclopedia: Global Warming

Dr. Cindy Parker of Johns Hopkins University answers questions about climate change.
The Public Health Effects
Air Pollution
The Greenhouse Effect

• Climate Change vs. Global Warming
• Is It Too Late to Stop Global Warming?

Browse All Global Warming Videos

Seas could rise by nearly 23 inches according to a recent study. See this and other effects of climate change.
View Photo Gallery

• EPA Climate Change Site
• What's Known and What's Uncertain
• Resources for Where You Live

Learn how your energy choices contribute to global warming.

• Go to the Calculator

• 'An Inconvenient Truth'

• 'The Great Warming'
• 'Planet Earth: The Climate Puzzle'

• International Report on Warming Warns of Threats
• Latest Global Warming Headlines

Take a look at some global warming data -- statistics scientists have compiled about carbon dioxide, temperature levels and melting ice. We've included some climate projections, too.
Global Warming Statistics

Think you know all about the greenhouse effect and global warming? Test your knowledge.

• Global Warming Quiz