Which greenhouse gas is most prevalent in the Earth's atmosphere?

Carbon dioxide is the most prevalent greenhouse gas in the Earth's atmosphere, playing a crucial role in the greenhouse effect, which warms the planet. While other greenhouse gases such as methane and nitrous oxide have a significantly higher global warming potential on a per molecule basis, their concentrations in the atmosphere are much lower compared to carbon dioxide.

The presence of carbon dioxide is primarily due to human activities, such as fossil fuel combustion, deforestation, and various industrial processes, which have led to its significant increase since the Industrial Revolution. This rise in carbon dioxide levels has been a major factor in climate change, making it a key focus for environmental policy and science.

Ozone, while important in the atmosphere for blocking harmful UV radiation, is not considered a significant greenhouse gas when discussing the overall contribution to global warming compared to carbon dioxide. Thus, the widespread presence of carbon dioxide, alongside its long-term impact on climate change, underscores why it is recognized as the most prevalent greenhouse gas.