Since its atmosphere consists mainly of CO 2, a known greenhouse gas, once the planet begins to heat, more CO 2 enters the atmosphere from the frozen reserves on the poles, adding to the greenhouse effect.
A known greenhouse gas enters the atmosphere from the frozen reserves on the poles. A known greenhouse gas is more CO 2. The planet begins to heat. A known greenhouse gas, once the planet begins to heat, is adding to the greenhouse effect. Its atmosphere consists mainly of CO 2.