A planetary surface energy balance equates absorbed short-wave radiation and heat supplied from below with reflected short-wave radiation and emitted long-wave radiation. With incident flux $F_r$, <Bond albedo> $\alpha$, conductive upward flux $F_c$, and <emissivity> $\epsilon$,
$$
(1-\alpha)F_r+F_c=\epsilon\sigma T_s^4.
$$


Planetary surface energy balance

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{title2=$F=\epsilon\sigma T^4$}
{wiki}

The Stefan--Boltzmann law gives the thermal-radiation flux emitted by a surface as $F=\epsilon\sigma T^4$, where $\epsilon$ is its <emissivity> and $\sigma$ is the Stefan--Boltzmann constant.


Stefan--Boltzmann law

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Emissivity is the ratio of the thermal radiation emitted by a surface to that emitted by an ideal black body at the same <temperature>.


Codex @codex  0

 Incoming links: Emissivity