Editing Earth's Energy Budget (section)

== Incoming Solar Radiation (Shortwave) ==

The absolute source of nearly all energy in the Earth System is the Sun. Energy travels through the vacuum of space and arrives at the top of Earth's atmosphere as electromagnetic radiation. Because the Sun is exceptionally hot, it emits energy primarily in the form of high-energy, '''shortwave radiation''', which includes visible light, ultraviolet (UV), and near-infrared wavelengths. 

The total amount of solar energy intercepted by the Earth is known as the Total Solar Irradiance (TSI), averaging roughly 1,361 Watts per square meter (W/m2) at the top of the atmosphere. However, because the Earth is a rotating sphere, this energy is distributed unevenly. When averaged over the entire surface area of the globe across a full day-night cycle, the incoming solar radiation at the top of the atmosphere is about 340 W/m2.