Any gas in the atmosphere that absorbs and re-emits radiation in the infra-red range, so warming the atmosphere and planet's surface.
Any gas in the atmosphere that absorbs and re-emits radiation in the infrared range, so warming the atmosphere and planet's surface. The most important greenhouse gases in Earth's atmosphere are carbon dioxide, methane, and water vapour.
The most important greenhouse gases in Earth's atmosphere are carbon dioxide, methane, and water vapour.