Given the following information for a planet in another solar system, calculate the planet’s radiative equilibrium temperature. In this solar system, the sun has a radius of 500,000 km, and it emits 25,000,000 W/m2. The planet has an albedo of 21 per cent and it is 76,000,000 km from its sun.
At noon, incoming solar radiation (K↓) is 625 W/m2, and incoming longwave radiation (L↓) is 345W/m2. Given that the surface temperature is 17oC, the surface albedo is 12 per cent, and the surface emissivity is 0.94, what is the net radiation? (Ignore surface reflection of longwave radiation.)