Which triatomic oxygen molecule is also a greenhouse gas? Ozone is the triatomic oxygen molecule and a greenhouse gas.
Ozone is made of three oxygen atoms, written O₃, rather than the two atoms in ordinary atmospheric oxygen, O₂. Its bent molecular shape allows it to absorb particular wavelengths of infrared radiation, helping it retain heat in the atmosphere.
Ozone has different effects depending on where it occurs. In the stratosphere, the ozone layer absorbs much of the Sun’s harmful ultraviolet radiation. Near the ground, ozone is a pollutant formed through reactions involving nitrogen oxides and volatile organic compounds in sunlight, and it can damage lungs and plants.
A common mix-up is treating all ozone as beneficial. Stratospheric ozone protects life, while ground-level ozone is harmful. Ozone is also a much smaller greenhouse-gas component than water vapor or carbon dioxide, but its radiative effects still matter in climate science.