This graph shows how the amount of carbon dioxide, a greenhouse gas in the Earth’s atmosphere, has changed over time and how it is expected to change in the future.
Click on image for full size
IPCC 2001 Third Assessment Report
Our Atmosphere Is Changing!
The amounts of most gases in the atmosphere stay pretty much the same over time. However, the amount of greenhouse gases in Earth’s atmosphere has gotten larger over the last 150 years. This is mostly because of human activities such as chopping down forest trees, burning oil and gas, and making concrete roads, buildings, and parking lots. These activities affect Earth’s cycles such as the carbon cycle, the nitrogen cycle and the water cycle, and affect the amount of greenhouse gases in the atmosphere.
Greenhouse gases trap heat through the greenhouse effect. There were greenhouse gases in the atmosphere long before humans affected them. Having some greenhouse gases in Earth’s atmosphere is good for life on Earth because they keep temperatures mild. However, as the amount of greenhouse gases rises, so does Earth’s temperature. This is causing changes to environments and living things around the world.
Last modified August 13, 2004 by Lisa Gardiner.
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