Reply To: Questions regarding DPF.

[Brian H]

KeithPickering wrote:

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.

So if there’s no greenhouse effect, why is Venus hotter than Mercury? I’ve got a theory that explains the phenomena. You’ve got bupkus.

Meanwhile, it doesn’t matter whether the incoming solar radiation is absorbed by the surface or the clouds. Greenhouse works either way, because there’s still a lot of CO2 above the cloud layer. (Cloud tops of Venus are at about 50 km, pressure 0.1 bar, with a 96% CO2 atmosphere, that puts roughly 300 times more CO2 above Venus’s cloudtops than above anywhere on the surface of the Earth.)

And that 3%? What happens to it? It gets radiated away in IR, then gets absorbed, re-radiated, absorbed, re-radiated, until it eventually hits a CO2 molecule that absorbs the energy and keeps it as heat. So much, much less than 3% of that 3% ever gets out again. Which is why the surface is so hot.

It certainly cannot be taken as any kind of “example”, cautionary, horrible, or otherwise.

In other words: you’ve got bupkus.
“Ever gets out again”. You’ve really lost it. All even the most classic simplistic GH mechanism can do is introduce a lag, like directing a hose into a pail which fills then overflows, instead of directly hosing the ground beyond. Once the pail is full and overflowing (which would have happened long, long, ago – and very quickly) the total flow-through is exactly the same as the source volume from the hose. In other words, no run-away. [See above for explanation of why the positive feedback loops are mathematically, historically, and empirically imaginary.]

“keeps it as heat”. O Rly? Still just a temporary energy boost, a small temperature increase (on Earth) overall; contact transfer and convection take over right away. Net energy is on balance always moving from surface to atmosphere, employing every available mechanism (contact, convection, evaporation (if applicable and available), and radiation. All stronger from down to up than up to down. All.) The reason Venus is hot is most likely simply that the convection and heat transfer mechanisms in the absence of water are so slow, making for a longer lag. By the by, the boffins are still resorting to double-talk about instrumentation anomalies trying to explain why sensors suggest much more energy flux from than onto Venus. LOL

It can be argued that the main reason that Venus is so hot is because there is no mechanism to rapidly move surface heat above the cloud layer. As a result, it does not matter if the atmosphere is mainly CO2 or not, the planet is hot because the atmosphere does not contain a substance that is liquid at surface temperatures and condenses to form clouds above most of the atmospheric mass.

and

The fact that the Venusian surface temperature is the same after 58 days of sun light and 58 days of darkness is really the main reason I claim that the Sun does not heat the surface. (Venus rotates with respect to the Sun once every 116.75 Earth days.)

On Earth, the minimum expected difference would be 50°C for a 2,800 hour day, on Venus, no difference is reported.

The “official” explanation for Venus having a constant surface temperature is strong winds – I am not convinced and I have not seen any evidence to support that position.

IBID
The winds operate only miles above the surface anyway, where the thick and heavy gasses move very sluggishly, if at all.

Based on the available facts
–No Surface wind
–Constant surface temperature
–Extremely slow planetary rotation
I conclude that
–The Sun has no effect on the surface weather
–The temperature of the surface is driven by internal heating
–Because the atmosphere has only a single green house gas, the surface temperature is much cooler than would otherwise be the case.

IBID

Occam’s Razor is sometimes quite sharp. On GH theory, it operates as a very efficient guillotine. As Phil Jones is discovering. More drum and head rolls to come!