A "greenhouse gas" is any [[gas]] suspected of contributing to the theorized [[runaway greenhouse effect]]. Opponents of greenhouse gas emissions support the [[Kyoto Protocol]], a UN-backed treaty to regulate greenhouse gases.
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A '''greenhouse gas''' is [[gas]] that contributes to the theorized [[runaway greenhouse effect]]. Opponents of greenhouse gas emissions support the [[Kyoto Protocol]], a UN-backed treaty to regulate greenhouse gases.
The most important greenhouse gas is [[water vapor]].
The most important greenhouse gas is [[water vapor]].