Anthony Watts is a chump, I prefer to get my information from John Lear...

http://www.abovetopsecret.com/forum/thread284985/pg1

I really don't even know why we are arguing this...Venus isn't even that hot...

Not even - Advent already have remote viewing in their tech tree...Venusians sound like their distant relatives in fact...

I am glad we finally agree  venus is hot because of pressure and not CO2 cutting that silly argument out of the CO2->warming thesis posed by those who don't believe in natural variation of climate.

I knew that finally you'd come around.

What... I didn't say that, you misunderstood my examples ... I said pressure counteracts gravity without changing the internal heat of the gas ...

The only heating/cooling occurs from radiation loss of the gas, and a supply of external heat (=the sun).

I didn't mention CO2, that's not relevant for this example. I just wanted to show that pressure and energy are two different things.

Hot = energy

Pressure = force.

See... those are entirely different physical concepts.

Gosh this is hard to explain and I thought I finally had a good example and I failed at explaining it...

Do you understand the difference between energy and force?

I don't know how to explain it ... perhaps like this:

I have a stone. I put a stone on top of it. The stone at the bottom experiences 3 forces: 1 from the top stone, 1 from gravity, and 1 from the ground which prevents it from falling to the center of the earth.

These forces counteract each other, there is 0 net force. The stone is in equilibrium, it doesn't move, it doesn't do anything. It doesn't heat up. It doesn't gain any energy.

The thing is: if there is zero net force on an object, then the energy of the object does not change.

At most you'll get some deformation in the stone, if the crystal lattice cannot counteract the stresses that are applied to it. But that's just another physical process ... and in that case the energy of the stone will change, slightly, because its shape is changed.

An atmosphere is like the stone, except that it has no shape. Instead of a shape, it has a certain density and volume, for the rest it's really similar. An atmosphere can also counteract a force (the gravity force) without changing its energy.

Oh... maybe a small balloon is a good example. You can blow up a rubber balloon. Inside the balloon the pressure is higher than outside, because the rubber presses against it. The air inside the balloon will lose its heat to the surroundings and is in equilibrium with the rubber shell. It won't heat up, it won't change its energy, because there is no net force acting on it.

Temperature has nothing to do with pressure ... the pressure is a result of gravity acting on the mass of column of air - pressure cancels that force out.

Temperature will affect the density of an atmosphere, but whatever the temperature, the column of air will have an equal mass and thus an equal force (well almost ... if the atmosphere expands, more mass will be in an region of lower gravity pull, but I don't think that's a big effect, let's just ignore that).

(Unless you want to discuss a dynamic atmosphere where heat makes air expand, pressure drops etcetera, but those are variations with respect to an average pressure which is determined the gravity)

I dunno... if the basics of physics is not clear, how on earth can you agree on more complicated things like global warming?

If I say heating from the sun warms our atmosphere, and someone else says it's the pressure that heats the atmosphere, then we're really living in 2 different planes of existence with different laws of physics.

Such alien lifeforms will never agree on anything, because they exists outside of each other's reality.

Part of the problem is that the temperature increase is so damned small. It's hardly outside noise level... And prehistoric data are also subject to lots of uncertainties and noise.

I think the only "good" data are the very, very old prehistoric data of hundreds of millions of years ago, when the earth had much higher levels of CO2.

After all... what does a 0,6 degree rise in temperature really matter. A CO2 change of the order of 100 ppm is still too subject to noise if you dig in the historic (ice/sediment) records. A temperature change of 0,6 degrees has a lot of noise even if you measure it directly at present. I think you need to examine situations where there is CO2 of the levels of 1,000 ppm or higher, levels where there is a significant rise in temperature.

For example the plant stomata data seem to have noise of say 50ppm. It's hard to make conclusions for a 100 ppm rise. But it can constrain a 1000 ppm rise in CO2.

And data from those times of very high CO2 point to high-temperature (40 degrees anyone...), acidic, oxygen-deprived oceans, extensive deserts, forests near the poles, subtropical plant life at moderate latitudes...

I think that kind of stuff is pretty convincing.

It also jives with our current knowledge of physics. You input those levels of CO2 into a model that has all the physical laws and there you go, you get high temperatures.

But well... people are distrusting towards science, they think scientists are crooks (some are, but most of them are really nice people do their best for the common good). Or people believe in the bible and that the earth is 6,000 years old. It's hard to show people convincing evidence, when they've already made up their mind that physics is wrong, measurements are wrong, and that everything else is wrong too. And well... physics can be a bit hard to understand. For example, what is energy? What is a force? Most people never thought about these things, they don't care, don't understand and they make their choice on other grounds than solid reasoning. Just show someone a few flashy graphics, nice colors, tell how crooked science is and how the scientists are just after your money... and then they'll believe it, because they want to believe it. They don't know about physics but they do know that they don't trust scientists, so they trust the anti-scientists who convince them with some catchy phrases.

Well they don't understand how hard it was for science to arrive at this point. Science doesn't move quickly, you know. A lot has to happen before a scientific community as a whole changes their mind about something like global warming. This was hardly a topic 50 years ago, only a few people worked on this problem. Nowadays there is enough evidence to make it mainstream.

What is the point you want to make with those links?

Oh... I suppose you mean that temperature increases with pressure as you move down the atmosphere.

But you know, the pressure itself doesn't create the heat.

It just means that you if take a piece of atmosphere with a certain energy then as you move it down, its energy will stay the same. The volume will become smaller, the temperature increases somewhat.

But what you fail to see is, that the pocket of air already has some energy to begin with, before you move it down. Where does this energy come from?

It doesn't come from pressure ... it comes from the sun. Pressure doesn't create any heat...

Without the sun, the atmosphere would simply cool off. The pressure at the earth's surface would remain the same, but the temperature would drop and the density of the atmosphere would increase...

If you want to clarify what you think is wrong.  Krazikarl was right in that pressure is not the source of heat for planets.

This whole thread has become ridiculous, most people aren't even talking about the same thing anymore.

OK....the reason Australia is such a warm place is that it's on the bottom of the world and has the pressure of the whole planet pushing on it and heating it up...

I have a feeling that Physics has changed quite a bit since I went to school....certainly it seemed a lot different in the 1960's to what people are 'explaining' now...

I'd love to see your explanation if you can manage to get over yourself.  In the case of the Earth and Venus, surface heat comes from solar irradiance.  Core heat comes largely from radioactive decay.  Being under constant pressure does not generate heat unless the pressure is so great as to start fusion.  If there is a pressure change and volume change (new work is done), then temperature will change proportional to the change in volume, but the heat energy within the system is not changed.

We are not talking about changes in pressure.  We are talking about constant pressure of the atmosphere.  The heat source of the atmosphere is the sun.  The only time pressure is a major source of heat in planetary temperatures is during formation, when there is a pressure change.  It takes a long time for this heat to radiate back into space, but it will eventually.

Why not...

It's not like I care any more about a permanent ban than I do temporary ones.

Krazi is wrong because he's arguing a fiction.  Whether the fiction was the intended claim or not I don't know.  I'm psychotic, not psychic.

The more pressurized a gas is, the higher it's heat capacity is over a given area.  There is more of it to store heat.  The oceans on Earth store massively more energy as a result of this.  The density of water is several hundred times that of the atmosphere above it, the greater heat capacity of water itself is a comparably trivial addition compared to the sheer mass.

On Venus, the atmosphere is itself a massively dense mixture with horrendous heat capacity compared to our own atmosphere.  If you could survive it, you could swim through the stuff.  CO2 acts on a small band of infrared compared to water, if anything the greenhouse effect is lower on Venus due to the near complete lack of a far more powerful greenhouse gas.  It does, however, have over 90 times as much of the stuff.  Thermal Inertia, look it up.

It also has an extremely slow retrograde spin.  Which means the cloud layer that reflects nearly all visible light and most of the rest of the spectrum as well is burning itself around the globe at a rapid rate.  You can see it in the pictures, the polar sections are smooth cloud cover, the equator is a roiling mess.  That isn't infrared being trapped by CO2 at the surface.  The surface of Venus is a uniform temperature between day and night, with light breezes of a few kmh at the surface.  Not that the breezes are light, they'd smack you on your ass in slow motion.  The temperature fluctuations are allmost entirely contained in the upper atmosphere.

Pressure does have limited warming effects as well, but friction isn't a major factor on Earth.  On Venus it should still be a fairly minor portion, but you have to recognize the fact that Venus' atmosphere is less like Earth's atmosphere than it is our oceans.  When hot air rises, and cold air flows in, only part of the work done has been powered by solar output.  The rest has been done by gravity.  Friction causes heat created by gravity.  More pressure means more friction.  Still, this should be a minor factor compared to the massive capacity for Venus to store heat that is completely irrelevant to whether CO2 is even there at all.

The absurd claim that there were oceans on the planet several hundred million years ago, and that it was a runaway greenhouse effect that got rid of them is preposterous.  The planet has no dynamo, and a day that lasts so long that water would be boiled off into the upper atmosphere and ripped away by solar wind.  If once there was, a cataclysmic event took place to radically change it's orbital mechanics, glass the entire surface, and stop the core from spinning.  A massively dense atmosphere comprised almost entirely of CO2 is the result of the conditions on Venus, not the cause of them.

The idiocy required for scientists that should know better to blame the state of Venus on CO2 is unimaginably staggering.  As such I just assume they're corrupt, a much less unreasonable position to take.