Learn about the balance of Earth’s incoming and outgoing energy with this slideshow adapted from NASA. Radiation from the Sun—Earth’s primary source of energy—enters the Earth system, where it can be reflected, absorbed, and emitted. Some energy gets absorbed by materials such as the land, ocean, and atmosphere. Some energy is reflected back to space by clouds, dust, snow, and ice. Some energy is radiated back and forth between the surface and the atmosphere because of the greenhouse effect. Earth’s energy budget is the total amount of incoming and outgoing energy. For a stable climate, the energy budget needs to be balanced. In recent years, there has been a small positive imbalance, with more energy coming in than going out.
To view the Background Essay and Teaching Tips for this slideshow, go to Support Materials below. This resource was developed through WGBH’s Bringing the Universe to America’s Classrooms project, in collaboration with NASA. Click here for the full collection of resources.