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Greenhouse Effect Feature Summary

From Physics Research
Greenhouse Effect
This is the famous "Keeling curve" of carbon dioxide concentration in the atmosphere versus time, from about 1958 to about 2007, measured in Hawaii. Notice that the rate of warming (indicated by the slope of the blue line) increases slowly but steadily over time.

Carbon dioxide is an important greenhouse gas. Greenhouse gases absorb the infrared radiation given off by Earth. This absorbed radiation is promptly re-emitted in all directions; much of it returns to Earth, raising the temperature of its surface by a substantial 33°C.

Carbon dioxide is produced by burning fossil fuels. As more countries industrialize, the use of fossil fuels increases, as does the amount of carbon dioxide in the atmosphere

The inset in the graph shows the annual cycle: For six months, plant photosynthesis absorbs carbon dioxide from the atmosphere, and the curve goes down; then, for the next six months, the decay of dead plants returns carbon dioxide to the atmosphere, and the curve goes up.

To learn more, visit Greenhouse Effect and also this UCAR page.
image credit: Robert Rhode (Wikimedia Commons); <a href="" target="_blank">image source</a>; <a href=" curve large.png" target="_blank">larger image</a>
image credit: Robert Rhode (Wikimedia Commons); image source; larger image
Image URL: curve large.png
May 1, 2013 - May 16, 2013