Reply To: Questions regarding DPF.

[jamesr]

The ‘surface’ as far as incoming radiation goes doesn’t have to be the solid planet surface. For Venus the surface for the Sun’s visible light is the layer of dense sulphuric acid clouds around 60km high where most of it is absorbed/reflected. The dense mid-level atmosphere is warm and so is the entity re-radiating in IR, blanketing the planet.

I wouldn’t be surprised if the total radiation coming from Venus is more than is coming from the Sun. The planet like ours (but less so) still has a hot core producing some heat through radioactivity but is overall cooling by radiating the heat into space. This is not anomalous.

The day/night side temperatures are not the same – see http://www.esa.int/esaMI/Venus_Express/SEM5A373R8F_0.html for more details.