If the Earth and the Earth’s atmosphere retains more solar energy than it radiates back to space, the Earth will warm. If the Earth and the Earth-system radiates more energy to space than it receives from the sun, the Earth will cool.
Scientists think of the Radiation Budget in terms of a see-saw or balance. If the Earth retains more energy from the Sun, the Earth warms and emits more infrared energy. This brings the Earth’s Radiation Budget into balance. If the Earth emits more of this energy than it absorbs, the Earth cools. As it cools, the Earth emits less energy. This change also brings the Radiation Budget back into balance.
Absorbed sunlight raises the Earth’s temperature. Emitted radiation or heat lowers the temperature. When absorbed sunlight and emitted heat balance each other, the Earth’s temperature doesn’t change – the radiation budget is in balance.