Earth's Surface Energy Balance

Abstract

AbstractThe Earth's surface energy balance is presented with the up‐to‐date information. The flow of energy is traced from the Sun through the atmosphere till it reaches the Earth's surface. The attenuation of solar radiation in the atmosphere is presented with respect to scattering and absorption, using satellite measurements, model simulations, and the radiation measurements at the surface. The transformation of solar radiation at the surface into various forms of energy is quantitatively illustrated with information obtained by direct flux observations and simulations by GCM. The atmosphere/surface‐combined system absorbs 70% of radiation coming from the Sun, of which 27% and 43% are absorbed by the atmosphere and the Earth's surface, respectively. On the surface, the largest amount of energy, 25% of the primary solar radiation, is expended for evaporation, 13% for net longwave cooling, and 5% for direct heating of the atmosphere. Therefore, the radiative energy at the surface is mainly converted into water vapor and participates for heating the system only by forming clouds. While evaporation takes place slowly from the entire Earth's surface, the formation of clouds happens in restricted space and time. This mechanism contributes to the enhancement of extreme precipitation and temperature in warming climate.