Long description

This is a schematic diagram shows yellow arrows representing radiation from the Sun reaching the surface of the Earth, now with its atmosphere. Red arrows represent infrared radiation given out by the Earth’s surface, but most of this radiation is absorbed and re-emitted in the atmosphere and by clouds before it reaches space, and some returns to the surface. The text on the diagram explains that the mean temperature of the Earth’s surface is a warm 15 degrees Celsius, that the two flows of radiation are again in balance, but that now the infrared radiation is mostly emitted from the colder upper atmosphere, not the Earth’s surface.