PV = nRT
The three variables are P, V and T. n doesn’t change. R is a constant.
If gases were perfectly compressible, the volume would decrease inversely proportional to the increase in pressure. There would be no reason for the temperature to increase.
But gases are not perfectly compressible. V does not decrease linearly with increases in P. In order to keep the Ideal Gas Law in balance, T has to increase.
It is all very simple, which is why climate scientists can’t understand it.
lol, is trick. It isn’t that complicated. Are you ever going to share with the warmistas where GHG’s come into play? Or just let them twist and talk circles around themselves?
suyts, so you still think all of planetary temperature comes down to the ideal gas law, and radiation plays no part? You guys REALLY should team up for this nobel prize
chris, what part of my post stated that? And, BTW, its Steve’s and Omni’s prize, not mine. Chris, when you first came to this blog, I was very optimistic that you would be able to contribute to the collective knowledge here. Sadly, I see that you’re an ideologue first and maybe a scientist second…….maybe. I’m going to do you a favor. Read on.
Chris, what part of the word “law” do you not understand? Science and math laws aren’t optional. You can’t simply jump up and call “no counts” because it doesn’t fit your worldview. You’re supposedly a scientist. You don’t think this law can’t apply, show it. Or, here’s an idea, try and figure out why and where current GW theory may fit into one or more of the variables…….. try thinking like a real scientist instead of embracing your religion.
Damn double negatives. don’t think this law can apply…. or think this law can’t apply….. either way.
And Chris, yw.
I never said the ideal gas law didn’t count, I claimed no one here seems to understand it, and I think there’s plenty written here and elsewhere on the web to understand why
Please … If you have an objection to something be specific. The article is only a few sentences long.
GHG’s have nothing to do with it. They do affect the temperature near the surface and the amount of convection, but they don’t have any role in the actual compressional heating.
You know they strongly affect the radiation balance, and thus warm the planet. Pressure isn’t the answer. You are a shameless liar.
Your response again belies your lack of understanding and bad attitude.
Let me try again – real …. slow …. like. The ground heats from the Sun, emitting LW radiation. Most of this gets absorbed by GHG near the ground surface. The warmed air rises, driving convection. What part of that don’t you understand?
stevengoddard says:
April 20, 2011 at 1:23 am
Then what does have a role in compressional heating? Compressional heating implies that work is being done on the system, so what is doing the work?
I disagreed with this hypothesis several months ago and I won’t change my mind on that until a rigorous explanation on what is doing the work is given.
-Scott
You only quoted one sentence out of three. The other two sentences answered your question.
Scott, wouldn’t you consider pressure the work?
So convection caused by GHGs do the work?
-Scott
The Sun does the work. Convection is driven by two mechanisms. 1. Heat absorbed by the air directly in contact with the ground. 2. Heat absorbed by greenhouse gases near the ground.
So the sun heats up the air, which has to raise its temp. Then, that hotter air increases the pressure, making it hotter? Seems circular to me.
-Scott
Heating air increases the volume, which is why the hot air rises. During the afternoon, atmospheric pressure actually drops as the air heats – due to the rising gases.
suyts says:
April 20, 2011 at 1:40 am
No, pressure is typically the result of the work. For instance, if we could somehow compress the entire atmosphere to make it smaller, it would heat up.
-Scott
Ok, Scott, we’re looking at it from a different perspective…..
I see it this way, pressure = force/area.
Force = mass*acceleration Units of force = Newton.
Newton meter/second = watt
Watt is expression of energy.
Still, that isn’t sufficient to come to an understanding of how the “ideal gas law” applies here. At this point, I’d say that Steve and I probably look at this from two different perspectives. And I’ve got to say I’m a bit disappointed that it isn’t greatly appreciated(by many commenting here) about viewing things from a different POV. Consider the cylinder……circle….rectangle….etc. Its the same thing only expressed differently depending upon the perspective.
Are you aware of a law in science or math that becomes invalidated becomes of the issue being considered? I’m not.
See my question on multiple competing hypotheses below. Back in the day, it was a more common approach. 😉
-Scott
PV=nRT… that’s what I said on your other blog you poop! But seriously, good job Mr. Goddard.
Well that is the ideal gas law. ;^)
Yes it is, sir. Sad that others who read your blog don’t seem to get it.
We get what he’s saying, we just don’t agree with his conclusions or want more detail. Many of the people disagreeing work with this stuff regularly, and no, not in climate models either.
-Scott
Okay, so lets say that your hypothesis looks valid. Well there’s another one that seems to explain the evidence too…the combination of radiative transfer theory with GHG absorbing.
So how do we utilize the method of multiple competing hypotheses to distinguish which is right? Can you arrive at approximately correct values using an ab initio calculation?
-Scott
It is a very complex problem, which is why we have weather and climate models. ;^) People who claim that global warming is “basic physics” have no idea what they are talking about.
Scott, do you believe these are competing thoughts? Or could it be two different explanations of the same thing? Do math rules compete or compliment each other? It is true, there are paradoxes in life, but I’m not sure we’re discussing a paradox in this instance.
suyts,
I would be happy to conduct scientific dialogue, but it is very hard to do that when people don’t understand the very basics, and then come to the conclusion that decades worth of science is all wrong based on that ignorance. I also contributed several scientific points and papers in the other thread, but you dismissed it on the basis a “model” was used (but apparently accept that the model of pV=nRT explains everything here), and ignored the rest.
In equilibrium, the temperature cannot exceed what is determined by energy balance….unless Goddard is also claiming to have circumvented conservation of energy too. As I discussed in the last thread, you can see GHG’s reducing the outgoing radiation from space. This is very basic physics, and if you could show why it is wrong you would invalidate much of what we know about atmospheric physics, satellite retrieval, quantum physics, etc. So why is Goddard not publishing in the literature and becoming the next Albert Einstein? It’s because he knows he’s wrong, and would rather fool a handful of gullible people on his blog instead.
When you have sufficient enough incoming sunlight and GHG’s in your atmosphere, you generate a non-convective temperature gradient greater than the adiabatic lapse rate, and convective instabilities force the gradient to be reduced to that appropriate adiabat. With no GHG’s, energy flows disappear and the atmosphere would become isothermal, at the skin temperature (where the tropopause migrates to the surface in the limit of zero optical depth).. The whole point of the greenhouse effect is that it reduces the radiating pressure (increasing the radiating height) of the planet, so one must extrapolate further along the adiabat to reach the (now higher) surface temperature.
You are the one circumventing thermodynamics by ignoring convection.
When did I make a claim that energy is not balanced? You raise yet another straw man.
Sure convection occurs…hence the adiabat. He really don’t know what you are talking about, do you? You should definitely be a lawyer. The thermal balance in
the troposphere is between radiative cooling and convective heating, and the height of convection essentially defines the tropopause.
By the way, Ch. 3 and 4 of Ray Pierrehumbert’s Principles of Planetary Climate discuss tropopause height and the lapse rate in the optically thin and optically thick limit in heavier mathematical detail
Be more specific with your ad homs. You have not raised a single specific objection to my article.
Why are you talking about a zero GHG straw man anyway? Both Earth and Venus have lots of GHG’s. What is the point of constantly taking the discussion to an irrelevant boundary condition?
“but it is very hard to do that when people don’t understand the very basics, and then come to the conclusion that decades worth of science is all wrong based on that ignorance.”
=============================================
Chris, you really don’t read nor understand what I write. First, climate science has invalidated itself, and I came to that conclusion by seeing their failed predictions and false assumptions. That conclusion has absolutely nothing to do with the “ideal gas law”. It has to do with the performance of climatology. Look out the window! Global temps have declined for over a decade in spite of ever increasing GHGs. Climatologists told us a warming planet is what caused the snow the last two winters……they also told us it was the reason for the lack of snow in the winters prior. All the while the globe was slightly cooling. Hansen is delusional to the point of ridicule. The dishonesty is flabbergasting. Don’t get me started on dendrochronology. But it doesn’t go without notice that very few of your colleagues ever call them out as you’re attempting to do to Steve.(and failing) In fact, it took a professional statistician to engage and invalidate the asinine treeometers. Where were you?
Let’s be clear, I didn’t declare the science wrong. They did. They’ve invalidated themselves.
Now, as to the discussion at hand. I had incorrectly assumed you would understand what I posted originally on this thread and I was really sure you would understand my second post. I would encourage you to re-read it.
PV=nRT. Now this is either true or it isn’t. I believe it is true. I don’t have to prove it, because it already has been, several times over and the law was reached independently by a few different people in different disciplines.
Gosh, I’m gonna be hated for this, but I’m a sharer of knowledge to the people that would hear.
So Chris, I hear you’re a science guy. Maybe you could answer a few questions I have.
PV=nRT I get most of it, but………
Pressure, what causes that?
Volume, can you think of what that might entail?
What’s that n thingy?
Is there anything in there that could change as to cause a 0.5 degree C increase in temps?
Do people really get paid money to sit around and think about sciency stuff and what qualifies for a scientific thought? Cause I’m thinking if people are getting paid to be wrong, how much is it worth to set them right?
I should have added, for the ones that can’t follow as well as others, are there other laws of science and nature that would define some of the variables? Would this formula also define other variables in other laws of physics?
Absolutely nothing!
The entire time I have read anything from our guest he has stuck to defending the undefendable fraud that is climatology.
You would do better slamming your head against a block wall. Partial truths to make you think he knows what he is talking about. But he really has no friggen clue about weather. Weather is all the above with Human indued GHGs being a bit player if at all and probably sitting on the sidelines is more likely!
Climate is long term weather patterns that can be expected in a particular region. Average climate is meaningless as is Global Climate. AGW is a FOOL’S errand! Most of humanity’s advances have been a result of adapting to regional climate factors (Weather Patterns).
The greatest human induced factor in climate is the corrupted records they are claiming represent historic climate!
One could actually say there has been no statistically significant climate change for the last 5000 years as the climate has been doing what it does naturally and nothing during the last 50 years is outside of natural variations as represented by the last 4 Million years!
lol, well, I’m trying one last time. But, you’re right, it is a fool’s errand. The sooner we can get people like him to realize this, the sooner society can get back to the real work of advancement of humanity.
It’s a pity to see Colose go back to the same tired arguments.
Think at what happened to McIntyre and McKitrick in their rejected Nature article. Think then at what happened on a lesser scale to me in my rejected Nature peer-reviewed comment (approved by both peer-reviewers, recommended for publication by them and then rejected by the Editors…so much for PEER review. Editors of Nature are NOT my peers, thank you very much).
Now, unless I have been victim of an extraordinary case of bad luck, and McIntyre and McKitrick too, it is obvious that the only people that will see plenty of their stuff published are those that get paid to see their stuff published. And can try, try and try again.
I can’t.
For me and countless others in the blogosphere (Goddard included, I suspect) the effort of seeing anything published in the peer-review world is actually a loss of money. It is therefore demonstrated that there are enough barriers to prevent anything from us from ever being published, apart from exceptional circumstances (such as, reaching pension age, or having a rich uncle die prematurely).
We can now call this officially the Private Communication Fallacy, to be added to the list of logical fallacies: when something is seemed wrong because it has been written only in a private communication (or a blog), instead of the peer-reviewed literature, by a person whose access to the peer-reviewed literature as author is difficult already, and made impossible by current (and old) practices.
As for those practices, google “Reg Sprigg” or “Elkanah Billings”.
“when something is considered wrong”
oops
Because of the experiences of many that attempt to publish a contrary view and what passes through as PEER Reviewed Science in Climatology and a few other disiplines the published work is within the realm of garbage with a few pearls of wisdom hiding within. Time MAY sort out the Chaff and leave the solid science.
Whether I agree with your claims or not I appreciate your sharing your thoughts.
Agreed, and there are plenty more examples of rejected publishing. I never took peer-review as a euphemism for truth anyway. After all the garbage I’ve seen passed off as science, I can’t fathom how some would still believe the process is viable. Like minded ideologues agreeing with each other. If I were a leftist alarmist I could get published, too.
I invite everybody to follow Chris’ recommendation and read Ray Pierrehumbert’s Principles of Planetary Climate (Look Inside! at Amazon.com is available).
Amazingly, at page 299 it confirms my suggestion that you find the ground temp starting from the tropopause temp. At page 300 it explicitly simplifies its model of the troposphere by getting rid of radiative effects (iow, by assuming GHGs have no effect in the troposphere). It then says radiative equilibrium is what defines the stratosphere. Etc etc.
I am having a strange feeling, I have been channeling raypierre and didn’t even know it!! 😎
And I have another strange feeling too. For Raypierre is interested about the atmosphere, whilst all this talk so far has been of global warming, in the sense of warming at the surface, ie at the bottom of the troposphere (a tiny part of the atmosphere, for an atmospheric scientist).
What if additional GHGs do warm the atmosphere, but only have minor or no effect on tropospheric bottom temperatures?
Very nice Omn! Chris should feel proud he helped confirm one of your thoughts!
Are you suggesting that heat retention from GHGs is sequestered from the surface?
Its late for me, but I believe that would be picked up by the satellite data………… good hunting.
PV = nRT
The three variables are P, V and T. n doesn’t change. R is a constant.
If gases were perfectly compressible, the volume would decrease inversely proportional to the increase in pressure. There would be no reason for the temperature to increase.
As it does if you compress the gas isothermally, nothing to do with ‘(im)perfect compressibility’.
If you compress the gas adiabatically then PV^k is constant where k is the ratio of the specific heats: k=Cp/Cv
Then temperature does go up: T2=T1(P2/P1)^(k-1)/k
But gases are not perfectly compressible. V does not decrease linearly with increases in P. In order to keep the Ideal Gas Law in balance, T has to increase.
Again nothing to do with the ‘perfect compressibility’, just depends on how fast the gas is compressed
It is all very simple, which is why climate scientists can’t understand it.
It’s all very simple, freshman thermo, which is presumably why Goddard can’t understand it. Perhaps they didn’t teach it in ‘the Harvard of the South’?
Phil – have you read Ray Pierrehumbert’s book? Please do, page 299 onwards. The “immediate return to adiabat” assumption (for the troposphere) is freshman thermo indeed.
You are a piece of work. If the volume decreased inversely proportional to the pressure, then the temperature can’t go up.
And it doesn’t which is why it’s called an isothermal compression! Do try to keep up.
Why are we talking about isothermal compressions? Where are those happening?
Steve made an original posting on the case of compressional heating based on kinetic theory of gases and made an incorrect statement, namely that the reason gases heated on compression because of “imperfect compressibility”. This is wrong, the heating occurs if the compression is fast enough that no exchange of heat takes place, i.e. the process is adiabatic. If the compression takes place slowly enough that heat exchange can take place then the process is isothermal. Often the compression is neither and is termed polytropic i.e. the effective k is lower than the ideal. When Steve tries to give lectures on kinetic theory of gases he should get it right.
Complete BS. The reason why you have to do work to compress gases is because the closer the finite sized molecules get the more resistance you face -i.e. not perfectly compressible like an “ideal gas” would be.. Thus you heat the gas – which later returns to thermal equilibrium at a lower volume.
You will do anything to avoid the central topic which is that Sagan and most of the climate science community is wrong about the runaway greenhouse effect. was wrong.
So in summary
http://lasp.colorado.edu/~bagenal/3720/CLASS14/EVMgreenhouse.jpg
Andy
stevengoddard says:
April 20, 2011 at 1:09 pm
Complete BS. The reason why you have to do work to compress gases is because the closer the finite sized molecules get the more resistance you face -i.e. not perfectly compressible like an “ideal gas” would be.. Thus you heat the gas – which later returns to thermal equilibrium at a lower volume.
That is complete BS, we’re not talking real gases here, ideal gases will heat up because compression is fast enough to be adiabatic, if compressed slowly the compression will be isothermal. Do yourself a favor, take some classes on kinetic theory of gases and stop embarrassing yourself with this nonsense.
Compressional heating has nothing to do with real gas effects!
The work done on compressing an ideal gas is given by the integral from V1 to V2 of PdV, if it’s adiabatic PV^k is constant, if it’s isothermal PV is constant.
You will do anything to avoid the central topic which is that Sagan and most of the climate science community is wrong about the runaway greenhouse effect. was wrong.
This idea you have is based on your poor knowledge on the subject, whenever you’re caught in an error you run away yelling “Sagan was wrong”, without ever saying what he was wrong about!
What a load of crap. If you compress a gas very slowly, the heat dissipates at the same rate as it is created making the temperature rise zero or “isothermal”. If you compress a gas faster than the heat can dissipate, the temperature rises. If gas molecules occupied no space, they wouldn’t create friction and heat.
You will do anything to avoid the central issue that Sagan and the climate science community was wrong about the runaway greenhouse effect. You nickel and dime irrelevant details and ignore order of magnitude problems.
Yes you are talking “a load of crap”, the idea gas law which assumes that the molecules occupy no space gives a rise in temperature when compressed adiabatically due to PdV work!
Further proof that you don’t have a clue about the subject. Like your previous rantings on the subject of CO2 ice at the South Pole your refusal to admit you’re wrong on the subject makes you look foolish. If you adiabatically compress gas from 0.1 bar to 0.2 bar you still get heating!
Phil,
This is exactly the same problem you had with the freezing point discussion. You are describing a coarse mathematical description of the average monte carlo behaviour, and I am discussing from the standpoint the physics of individual particles.
I never said that dry ice would accumulate at the south pole. What I said was that CO2 molecules freeze below the freezing point, which is a fundamental principle of physics. They don’t accumulate because the rate of sublimation is greater than the rate of freezing.
Likewise in this irrelevant discussion which you started it is a matter of how quickly the heat dissipates. You are a typical academic type who learns a formula and makes no effort to understand the underlying physics.
And you will do anything to distract form the central issue that Sagan was wrong about the runaway greenhouse effect.
stevengoddard says:
April 20, 2011 at 2:23 pm
Phil,
This is exactly the same problem you had with the freezing point discussion. You are describing a coarse mathematical description of the average monte carlo behaviour, and I am discussing from the standpoint the physics of individual particles.
Actually you claimed to be discussing it from the perspective of the Ideal gas law.
I never said that dry ice would accumulate at the south pole. What I said was that CO2 molecules freeze below the freezing point, which is a fundamental principle of physics. They don’t accumulate because the rate of sublimation is greater than the rate of freezing.
No it isn’t because you didn’t (and still don’t) understand the phase diagram, in other words you didn’t know what the freezing point of CO2 is under the atmospheric conditions on this planet.
Likewise in this irrelevant discussion which you started it is a matter of how quickly the heat dissipates. You are a typical academic type who learns a formula and makes no effort to understand the underlying physics.
No, I’m a scientist who understands the underlying physics, you on the other hand do not and resort to copying formulae off the web that you don’t understand.
In the case of adiabatic compression you assert that it’s a real gas effect due to the finite volume of the molecules, absolute BS.
If you heat a volume of gas the change in internal energy is Cv?T
In an adiabatic compression the work done is -P?V, since it’s adiabatic -P?V=Cv?T
Apply PV=nRT
-nRT/CvV=?T/T
but nR/Cv=k-1
so (k-1)?V=?T
differentiating gives TV^(k-1) = constant
or if you multiply through by PV/T (also a constant)
PV^k = constant
All done using the assumptions of the ideal gas law!
If you wanted to do it for a real gas you’d have to use something like this:
(P+an^2/V^2)(V-nb)=nRT
Which is much hairier mathematically.
I see, so you think that substances don’t freeze below the freezing point.
You’re a glutton for punishment aren’t you.
CO2 can’t freeze anywhere naturally on this planet because its triple point is at slightly more than 5 atmospheres pressure. Being charitable I assume you mis-spoke and meant deposition, the reverse of sublimation. Well that could occur on Earth but given the partial pressure of CO2 at the surface of the Earth is less than 1 mbar then CO2 will only deposit at temperatures below about -140ºC. Not happening!
ROFL Who said anything about a triple point? No one ever discussed liquid CO2.
Antarctica gets colder than the freezing point at one atmosphere.
Do you also think that the freezing point of water is dependent on the humidity? You might want to look up the difference between the freezing point and the *frost point* which you are confusing.
lol….why has the conversation drifted into an issue over ideal gas compression?
Even an ideal gas will heat up if compressed: since collisions of the ideal gas molecules with the walls of the container is assumed to be elastic, there will be an increase in the momentum of the particles as work is done ( a force is applied ) by the walls of the vessel on the gas particles, resulting (since the mass of the particles is considered constant) in an increase in their kinetic energy and hence an increase dU in the internal energy equal to the work dW done on the gas. since the internal energy U depends solely on the temperature T of the gas, the temperature will increase! Whether compression is isothermal or not depends on whether the rate of heat loss to a heat reservoir is very large or zero (depending on the time interval considered).
Hence Phil shows that goddard is talking BS but ultimately proves his point. Well done!
The freezing point of CO2 depends on its partial vapour pressure but CO2 will still freeze below the local freezing point.
lol, yeh, well, I’d reword it to, “Hence as Phil attempts to show that goddard is talking BS
buthe ultimately proves his point.Yes I do prove my point and Goddard is talking BS
You are so full of it.
lol, Sorry Phil, I wasn’t clear about the “his”. I took his to mean Goddard’s.
lol….why has the conversation drifted into an issue over ideal gas compression?
Because Goddard claimed to have proved that ideal gases don’t heat up when compressed and that compressional heating is a ‘real gas’ effect.
The freezing point of CO2 depends on its partial vapour pressure but CO2 will still freeze below the local freezing point.
Indeed a distinction that Goddard didn’t appreciate in our earlier discussion, he thinks that there is a freezing point below which CO2 ‘freezes’ regardless of its partial pressure!
Blah, blah, blah, blah. Where do you people come form?
The real world, not that strange planet where you appear to live.
I think that the mountain top analogy is much more helpful and to the point. The measured temperature of a gas depends on the heat transferred to the transducer acting as sensor. what causes this heat in the form of phonons? vibration of the gas molecules and of course, more molecules = more vibrations = more heat = greater temperature. no need to be a rocket scientist.
and oh…there are lots and lots of huge volcanoes on venus…and it is much closer to the sun…just saying…
Phil. says:
April 20, 2011 at 5:19 am
PV = nRT
The three variables are P, V and T. n doesn’t change. R is a constant.
The volume of the atmosphere is a constant (at least so close it would scare ya.). So if P changes T must change.
stevengoddard says:
April 20, 2011 at 7:59 pm
ROFL Who said anything about a triple point? No one ever discussed liquid CO2.
You did, freezing is the name given to the phase change from liquid to solid. To freeze requires the existence of the liquid phase, liquid CO2 can’t exist at partial pressures below 5.11 atm.
Antarctica gets colder than the freezing point at one atmosphere.
There is no freezing point at one atmosphere so know it doesn’t, you are referring to the sublimation point at one atm which is the temperature which a block of solid CO2 will stabilize at while subliming away at atmospheric pressure.
Do you also think that the freezing point of water is dependent on the humidity? You might want to look up the difference between the freezing point and the *frost point* which you are confusing.
That does appear to be one of your confusions.
Nope….Phil actually proves goddard’s point which is that the lower layers of the atmosphere of venus is heated due to compression from upper layers ( a process that of course also occurs on earth )…..lol…and Phil is labouring to show that indeed Goddard’s claim was right from the beginning…just that he had his explanation for the process all wrong.