Skip to main content
U.S. flag

An official website of the United States government

How does carbon get into the atmosphere?

Atmospheric carbon dioxide comes from two primary sources—natural and human activities. Natural sources of carbon dioxide include most animals, which exhale carbon dioxide as a waste product. Human activities that lead to carbon dioxide emissions come primarily from energy production, including burning coal, oil, or natural gas.

Learn more: Sources of Greenhouse Gas Emissions (EPA)