"This film is about the greenhouse effect, or more specifically, the atmospheric greenhouse effect and its causes and consequences. Due to its incredible surface temperature of approximately 5600 °K, the sun's heat radiation is made up of shortwave infrared. The glass or perspex in a greenhouse is just as transparent as visible light for these waves. This heat radiation increases the temperature in the greenhouse, meaning that the inside of the greenhouse itself becomes a heat radiator. But because the temperature inside is much lower than the sun's surface, this heat radiation is made up of longwave infrared. And the glass or perspex in the greenhouse is almost impermeable for that. This varying permeability for different radiations is called ""selective transparency"". Greenhouse gases, most of all carbon dioxide, have a similar effect to the glass in a greenhouse."