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• carbon cycle
• infrared
• greenhouse effect
• concentration
• carbon source
• Keeling Curve
• carbon sink
• Ozone
• greenhouse gas

Normally in the , the element carbon moves in the form of carbon dioxide from a , such as forest fires, respiration, or decomposition. When carbon is trapped in a , it decreases the amount of carbon dioxide in the atmosphere. Over the last few hundred years, the of carbon dioxide in the atmosphere has been increasing as is seen in the . Since carbon dioxide is a , this has caused the atmosphere to reflect more radiation back to Earth. This is known as the .

in the upper atmosphere is able to block dangerous ultraviolet radiation. Fortunately, the ozone hole is decreasing in size because nations have ageed to stop releasing ozone-destroying gases.