Animals and plants need to get rid of carbon dioxide gas through a process called respiration. Carbon moves from fossil fuels to the atmosphere when fuels are burned. When humans burn fossil fuels to power factories, power plants, cars and trucks, most of the carbon quickly enters the atmosphere as carbon dioxide gas.
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It could be classified if it is only felt by a small number of people. If it originated somewhere in the ocean or in a rural or unpopulated area where the surface material was especially resistant to damage.
