Nutcase

Is the Pig cracking up? Is writing in the third person a symptom? How about gloomily contemplating an Independence Day with the shards of our Constitution littering the ground all about us?

Well maybe. Or maybe he's just in a really cranky mood. Anyway, he wrote this long, rather nasty post deconstructing some of the blunders in Lumo's saturation extravaganza and the gazillion comments thereto. After some contemplation, he trashed it, concluding that making fun of the unenlightened was hardly a very worthy deed.

Reading those comments is one of those strange experiences, reminding me slightly of attending some stoner parties in the 1960's. A large crowd of persons, most of whom have only the vaguest idea of what they are talking about, gathered to celebrate their shared delusion and pretend that those who don't are the crazy ones.

I trashed the post, but a few moments had to be saved. First, the irresistably obtuse Larry R., as baffled as he is obnoxious, uttering his motto and fate:

And WTF is this?????[next, quoting Real Climate]

Any saturation at lower levels would not change this, since it is the layers from which radiation does escape that determine the planet's heat balance. The basic logic was neatly explained by John Tyndall back in 1862: "As a dam built across a river causes a local deepening of the stream, so our atmosphere, thrown as a barrier across the terrestrial [infrared] rays, produces a local heightening of the temperature at the Earth's surface."
So the Bernoulli effect in fluid dynamics has something to do with warming of the earth as it moves through space? I don't get it.

Indeed you don't Larry. You don't get the Bernoulli effect, and you don't get a simple analogy from 150 years ago. Just remember that last sentence and you could save yourself a lot of further embarassment (but he doesn't, of course).

Our host reveals himself to be unclear on a couple of key concepts:

I didn't say that ozone was completely saturated in the IR. I said that O2 - normal oxygen - was completely saturated at all long wavelengths. That's important because there's a lot of O2 in the atmosphere and if it had half-empty spectral lines in the thermal region, the changes of the O2 concentration would cause huge effects.

O3 is not saturated in the IR but it doesn't matter too much because the amount of O3 is tiny.

Actually, as a look at the images he has provided will confirm, O2 has strong absorption only in the UV - short wavelengths, not long - completely irrelevant for greenhouse effects. O2 also has a weak absorption feature in the near IR which is also irrelevant for greenhouse effects. O3, on the other hand, has a very strong feature around 9 microns, right smack in of the thermal window, so it is a player despite its parts per billion presence.

Lumo is also a bit unclear on the perfect gas law:

Is your lapse rate for "warm" gold mines a joke? Via the adiabatic calculation, a lapse rate only applies to gases, am I wrong? If you really think that gravity "attracts" the heat to the bottom of gold mines, could you be more specific with your evidence or arguments? Thanks.

Actually Lubos, gold mines are holes in the rock, filled with a gas, namely air. Because miners need to breathe, stale air is pumped out of the mines, allowing fresh air down the shafts to replace it. As that air descends, it is compressed by the weight of the atmosphere above it and its temperature increases according to the perfect gas law for an (approximately) adiabatically compressed gas - about 9.8 K per kilometer. Which is how the perfect gas law and gravity conspire to make deep gold mines hot as hell.

These types of key knowledge gaps help explain why a really smart guy can wind up deeply wrong.

UPDATE: "The deepest mine in this region (Witwatersrand) is currently Western Deep mine, a network of tunnels which penetrates 3.5 km into the Earth's crust."

UPDATE 2: Empedocles, in the comments, rather rudely reminds us of the geothermal gradient. Since the comments aren't working right now, here is my reply:

Empedocles,

Ah well, pigs, even the most equal of pigs, never claimed to have the minds of Greek (let alone Sicilian Greek) philosophers. Air is near enough to a perfect gas at the pressures involved that the adiabatic lapse rate is pretty close to the actual lapse rate, however.

But to address your point, yes, there is a geothermal gradient, and its magnitude of 20 K/km (or so) probably does make it more important than the nonetheless real effect I mentioned.

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