CO2 and Other Greenhouse Gas Variations
Many natural and human-made gases contribute to the greenhouse effect that warms the Earth's surface. Water vapor (H2O) is the most important, followed by carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and the chlorofluorocarbons (CFCs) used in air conditioners and many industrial processes.
The increasing atmospheric CO2 concentration is likely the most significant cause of the current warming. Other greenhouse gases along with other factors discussed in the following sections also contribute.
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Importance of Human-produced Greenhouse Gases
This diagram shows the relative importance of the major human-produced greenhouse gases to current warming. CO2 is the most important followed in descending order by methane, CFCs, ozone and nitrous oxide. |
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