Figure 6-49The Greenhouse Effect A portion of the sunlight penetrates through the clouds and atmosphere of Venus, heating its surface. The surface in turn emits infrared radiation, much of which is absorbed by carbon dioxide (and, to a much lesser degree, water vapor). The trapped radiation helps increase the average temperatures of the surface and atmosphere. Some infrared radiation does penetrate the atmosphere and leaks into space. In a state of equilibrium, the rate at which the planet loses energy to space in this way is equal to the rate at which it absorbs energy from the Sun.