Reply To: Questions regarding DPF.

[Brian H]

About 3% of incident radiation reaches the surface of Venus, as far as most sources can tell. Significant ground re-radiation in longer wavelengths absorbed by CO2 and then re-re-radiated (?!) thus doesn’t occur, which is the basis of any “greenhouse” effect. I.e., the atmosphere is directly heated by both on-planet sources and solar radiation. There are numerous “anomalies” in the radiation measurements, some even indicating that more heat is being radiated than comes from the sun. Additionally, the night and day sides of Venus are the same temperature, which could not be the case if it was controlled in any way by solar radiation. The high-velocity exclusively upper-level winds drop to almost zero at the surface, and thus cannot be responsible for mixing warmed daytime air with cooled nighttime air down where the great bulk of the atmosphere is. An “Occam’s Razor” hypothesis suggests internal heat sourcing and almost total reflection of solar irradiation before it affects the surface.

In any case, Venus is less and less like the Earth the more it is examined. The clouds are apparently composed of predominantly chlorine based compounds of some sort, for example. It certainly cannot be taken as any kind of “example”, cautionary, horrible, or otherwise.