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How do carbon dioxide, methane, and water vapour trap heat in the atmosphere?

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Wispy cirrus clouds stretch across a bright blue sky above trees and a river at Pinawa Dam Provincial Park in Manitoba, Canada, with sunlight illuminating the scene. — Atmosphere The atmospheres of planets in the solar system are composed of various gases, particulates, and liquids. They are also dynamic places that redistribute heat and other forms of energy. On Earth, the atmosphere provides critical ingredients for living things. Here, feathery cirrus clouds drift across the deep blue sky over Pinawa Dam Provincial Park, near Pinawa, Manitoba, Canada.

Carbon dioxide, methane, and water vapour contribute to the greenhouse effect by absorbing infrared radiation emitted from Earth’s surface and reradiating it back toward the surface.1

Carbon dioxide ( $C O_{2}$ ): This gas is a primary driver of radiative forcing. It remains in the atmosphere for hundreds of years, and its concentration has risen steadily due to human activities like fossil-fuel combustion.12
Methane ( $C H_{4}$ ): Methane is more potent than $C O_{2}$ because each molecule produces greater radiative forcing. It absorbs radiation in an "infrared window" that is less saturated, allowing more molecules to contribute to heat trapping. While it has a shorter atmospheric residence time of about 10 years, its concentration is increasing due to sources like livestock farming and natural gas use.2
Water vapour ( $H_{2} O$ ): Unlike the others, water vapour acts primarily as a climate feedback. Its atmospheric concentration is determined by air temperature; as the surface warms, increased evaporation leads to higher concentrations of water vapour, which then absorbs and reradiates infrared energy.3