Which of the following greenhouse gases has a warming potential significantly higher than carbon dioxide?

Chlorofluorocarbons (CFCs) are synthetic chemicals that were commonly used in air conditioning, refrigeration, foam-blowing, and aerosol propellants. CFCs have a much higher global warming potential (GWP) than carbon dioxide, often measured in thousands of times more effective at trapping heat in the atmosphere over a given period. This means that while carbon dioxide is a significant greenhouse gas, its warming effect is dwarfed by CFCs due to their ability to persist in the atmosphere and their effectiveness at absorbing infrared radiation. This property makes CFCs a critical focus in discussions about climate change and their phasedown under the Montreal Protocol, aimed at reducing substances that contribute to ozone depletion and global warming.

While methane and nitrous oxide also have higher GWP than carbon dioxide, CFCs surpass them by a substantial margin. Water vapor, while the most abundant greenhouse gas, acts primarily as a feedback mechanism rather than a direct contributor to climate change since its concentration in the atmosphere is regulated by temperature. Thus, the unique, high-impact characteristics of CFCs solidify their position as having a significantly higher warming potential compared to carbon dioxide.