This simple visual analogy that Ron House has designed can help readers not familiar with a contentious atmospheric modeling issue get a primer on the it. While not a perfect analogy (and by definition analogies often aren’t) it does help convey an important point: the predicted red spot has not appeared. For the more technically inclined,Ā or for those wanting more, Steve McIntyre posted an interesting discussion at Climate Audit. – Anthony
Guest Post by Ron House July 29, 2009
Let’s say it’s a cold night and Fred climbs into bed:
(A) Fred in bed.
Will Fred use a blanket to keep warm? If so, the air will heat up close to Fred because his body warms the air and the blanket prevents it from moving away. On the other hand, as the night progresses, the air beyond the blanket will cool:
(B) With a blanket, the warm air collecting around Fred warms him up.
In the picture, the “+” signs show air that becomes warmer, and the “-” signs air that becomes cooler.
Now what if Fred (forgetful Fred) didn’t use a blanket? The warm air escapes and tends to rise (warm air being less dense than cold air):
(C) With no blanket, warm air escapes and Fred shivers.
Poor Fred gets colder as the night wears on. But now we come to the point of the exercise: How do we know whether Fred used, or did not use, a blanket?
“Easy,” you say: “Take a look!” But let’s suppose that Fred is a very light sleeper, we dare not put on the light, so there’s no way we can see if there’s a blanket. Butāsurprise!āwe just happen to have an infra-red scanner that can tell us the temperature of the air at various spots throughout the room. Depending on whether Fred uses a blanket, the temperature change in the room follows one of the two characteristic patterns we saw above; so if we check where the air gets colder and where it gets warmer as the night wears on, we know, for a fact, whether or not Fred used a blanket, even without being able to see it. If Fred did use a blanket, our scanner should show results like this (note how we can’t see the blanket, but we can be sure that it is there):
(D) Warm air collects in a contained region, so there must be a blanket.
On the other hand, if he does not use a blanket, we will see the temperature change in a pattern something like this:
(E) Warm air escapes upwards, so we are sure there is no blanket.
Once again, there is no doubt at all what is going on. In science, nothing is absolutely certain, but depending on which temperature pattern develops, we can be very, very sure indeed of the answer to the question: Did Fred use a blanket?
Now we can turn to the global warming question, whether the Earth is surrounded by a ‘blanket’ of anthropogenic (human-generated) greenhouse gas stoking up the temperature of the planet. The physics of a real blanket (as with Fred in the fable above) and a gaseous ‘blanket’ around the Earth differ, but just the same, different heat dissipation (or retention) processes will result in different characteristic patterns of temperature change. Just as Fred will be surrounded by something roughly resembling one of two quite different patterns of air temperatures, so likewise will temperature changes around the Earth have a quite definite pattern, depending on which climate theory is right. Scientists whose paycheck does not depend on agreeing with global warming alarmism will all agree with this simple statement. It’s part of the basic skill of having a ‘nose’ for physics.
What, then, are our main competing climate theories? The IPCC’s reports are based on results from a collection of climate computer models; they have nothing else. These are simply computer programs that, in essence, contain a computerised version of the assumptions and beliefs of the climate modeller as to how the climate of the planet works. Whether these assumptions are well-founded is another question, but the key point is that whatever these assumptions may be, when the climate model is run, it generates its ‘predictions’ by calculation of hypothetical futures for the behaviour of the atmosphere. These ‘futures’ contain, as an essential element, predictions of the changes of atmospheric temperatures at various heights above the planet and the various latitudes all the way from south pole to north pole.
The indisputable fact about these atmospheric temperature predictions is that if the pattern doesn’t happen, the model is wrong. Just as Fred won’t warm up if he isn’t surrounded by warm air, likewise the effects on the Earth of global warming cannot happen if the cause of the warming āthe warm airāisn’t there.
So now we come to the graphs that clinch the matter. All global warming models predict some sort of developing ‘hotspot’ in the atmosphere above the tropics. Here is the graph for one of the models, but they all look roughly similar:
(F) Model predicts air above the tropics heats up. from the NIPCC Report p. 107
This picture shows the air from 75 degrees north to 75 degrees south (the equator in the middle) and up to 30 km above the Earth. We can think of this air pattern as corresponding to the pattern in Fred’s bedroom when Fred used a blanket: although the actual mechanism is different, something is ‘keeping the heat in’, so to speak. Just as we did with Fred in bed, we can compare reality with this picture. Is the heat in the real atmosphere doing what the model predicts? Here is the temperature trend in the real world:
(G) Real world trend develops no hotspot. from the NIPCC Report p. 106
What have we actually proved here? Well, proved, without possibility of error, nothing, of course: no question at all about the real world ever has a complete perfect proof as an answer, so don’t be misled if someone says the world still might be heating due to CO2 despite the absence of the warm spot that is supposed to do the warming. Of course anything might be happening; but how likely is it? Well how likely is it that Fred has a blanket, but the air around him is getting colder just as if he had no blanket, and yet Fred is warming up despite that? The two questions have the same answer: not very.
Yet surprisingly, some proponents of global warming alarmism actually resort to this very strategy. “True,” they say, “the hot spot isn’t developing. But that is because the heat is being stored up elsewhereāit’s “in the pipeline”āand one day it will burst forth with even greater severity and vengeance.”
What can we make of that claim? Well, thinking back to Fred again, it amounts to this: We use our temperature probe in Fred’s darkened bedroom and we see a pattern like that in (E) above, corresponding to no blanket: Fred should be freezing! But actually, the heat has all gone into Fred’s body, despite the complete absence of the hot air which is the mechanism for making it do so. In other words, Fred got warmer by disobeying the second law of thermodynamicsāin other words, by magic. Likewise, if someone says heat is being secretly stored somewhere by global warming, despite the absence of the very mechanism that does the warming, they are saying global warming is happening by magic. That is the harsh truth of the matter.
One thing I have learned whilst studying the global warming question is that, like many other physical systems, the climate is constrained by limits that can be understood by any intelligent person willing to learn some simple physics. The ‘hotspot’ is one of them. Anyone talking down to you and telling you you have to take the word of some mythical ‘consensus’ of ‘experts’ is trying to hoodwink you.
Let’s say it’s a cold night and Fred climbs into bed:
(A) Fred in bed.
Will Fred use a blanket to keep warm? If so, the air will heat up close to Fred because his body warms the air and the blanket prevents it from moving away. On the other hand, as the night progresses, the air beyond the blanket will cool:
(B) With a blanket, the warm air collecting around Fred warms him up.
In the picture, the “+” signs show air that becomes warmer, and the “-” signs air that becomes cooler.
Now what if Fred (forgetful Fred) didn’t use a blanket? The warm air escapes and tends to rise (warm air being less dense than cold air):
(C) With no blanket, warm air escapes and Fred shivers.
Poor Fred gets colder as the night wears on. But now we come to the point of the exercise: How do we know whether Fred used, or did not use, a blanket?
“Easy,” you say: “Take a look!” But let’s suppose that Fred is a very light sleeper, we dare not put on the light, so there’s no way we can see if there’s a blanket. Butāsurprise!āwe just happen to have an infra-red scanner that can tell us the temperature of the air at various spots throughout the room. Depending on whether Fred uses a blanket, the temperature change in the room follows one of the two characteristic patterns we saw above; so if we check where the air gets colder and where it gets warmer as the night wears on, we know, for a fact, whether or not Fred used a blanket, even without being able to see it. If Fred did use a blanket, our scanner should show results like this (note how we can’t see the blanket, but we can be sure that it is there):
(D) Warm air collects in a contained region, so there must be a blanket.
On the other hand, if he does not use a blanket, we will see the temperature change in a pattern something like this:
(E) Warm air escapes upwards, so we are sure there is no blanket.
Once again, there is no doubt at all what is going on. In science, nothing is absolutely certain, but depending on which temperature pattern develops, we can be very, very sure indeed of the answer to the question: Did Fred use a blanket?
Now we can turn to the global warming question, whether the Earth is surrounded by a ‘blanket’ of anthropogenic (human-generated) greenhouse gas stoking up the temperature of the planet. The physics of a real blanket (as with Fred in the fable above) and a gaseous ‘blanket’ around the Earth differ, but just the same, different heat dissipation (or retention) processes will result in different characteristic patterns of temperature change. Just as Fred will be surrounded by something roughly resembling one of two quite different patterns of air temperatures, so likewise will temperature changes around the Earth have a quite definite pattern, depending on which climate theory is right. Scientists whose paycheck does not depend on agreeing with global warming alarmism will all agree with this simple statement. It’s part of the basic skill of having a ‘nose’ for physics.
What, then, are our main competing climate theories? The IPCC’s reports are based on results from a collection of climate computer models; they have nothing else. These are simply computer programs that, in essence, contain a computerised version of the assumptions and beliefs of the climate modeller as to how the climate of the planet works. Whether these assumptions are well-founded is another question, but the key point is that whatever these assumptions may be, when the climate model is run, it generates its ‘predictions’ by calculation of hypothetical futures for the behaviour of the atmosphere. These ‘futures’ contain, as an essential element, predictions of the changes of atmospheric temperatures at various heights above the planet and the various latitudes all the way from south pole to north pole.
The indisputable fact about these atmospheric temperature predictions is that if the pattern doesn’t happen, the model is wrong. Just as Fred won’t warm up if he isn’t surrounded by warm air, likewise the effects on the Earth of global warming cannot happen if the cause of the warming āthe warm airāisn’t there.
So now we come to the graphs that clinch the matter. All global warming models predict some sort of developing ‘hotspot’ in the atmosphere above the tropics. Here is the graph for one of the models, but they all look roughly similar:
(F) Model predicts air above the tropics heats up. from the NIPCC Report p. 107
This picture shows the air from 75 degrees north to 75 degrees south (the equator in the middle) and up to 30 km above the Earth. We can think of this air pattern as corresponding to the pattern in Fred’s bedroom when Fred used a blanket: although the actual mechanism is different, something is ‘keeping the heat in’, so to speak. Just as we did with Fred in bed, we can compare reality with this picture. Is the heat in the real atmosphere doing what the model predicts? Here is the temperature trend in the real world:
(G) Real world trend develops no hotspot. from the NIPCC Report p. 106
What have we actually proved here? Well, proved, without possibility of error, nothing, of course: no question at all about the real world ever has a complete perfect proof as an answer, so don’t be misled if someone says the world still might be heating due to CO2 despite the absence of the warm spot that is supposed to do the warming. Of course anything might be happening; but how likely is it? Well how likely is it that Fred has a blanket, but the air around him is getting colder just as if he had no blanket, and yet Fred is warming up despite that? The two questions have the same answer: not very.
Yet surprisingly, some proponents of global warming alarmism actually resort to this very strategy. “True,” they say, “the hot spot isn’t developing. But that is because the heat is being stored up elsewhereāit’s “in the pipeline”āand one day it will burst forth with even greater severity and vengeance.”
What can we make of that claim? Well, thinking back to Fred again, it amounts to this: We use our temperature probe in Fred’s darkened bedroom and we see a pattern like that in (E) above, corresponding to no blanket: Fred should be freezing! But actually, the heat has all gone into Fred’s body, despite the complete absence of the hot air which is the mechanism for making it do so. In other words, Fred got warmer by disobeying the second law of thermodynamicsāin other words, by magic. Likewise, if someone says heat is being secretly stored somewhere by global warming, despite the absence of the very mechanism that does the warming, they are saying global warming is happening by magic. That is the harsh truth of the matter.
One thing I have learned whilst studying the global warming question is that, like many other physical systems, the climate is constrained by limits that can be understood by any intelligent person willing to learn some simple physics. The ‘hotspot’ is one of them. Anyone talking down to you and telling you you have to take the word of some mythical ‘consensus’ of ‘experts’ is trying to hoodwink you.
There are two possibilities for where the “missing heat” is being stored. In the land or in the ocean. The oceans are not heating. In fact they may be cooling.
That leaves the land. Is there any evidence of the land heating?
BTW the hot spot is necessary for radiation balance. The earth heats in conformance to the second law from a hot body – the Sun – to a cool body – the Earth.
I think it’s a valid point – if reality isn’t doing what the models predicted, then the models are wrong, which shows in turn that we don’t fully understand what’s going on…
If the heat is ‘stored’ somewhere, & ‘in the pipeline’ then the models should show that.
Now this is an analogy that even MSM could grasp. I llike it!
Equally, I don’t think there are many people who dispute that CO2 in general has a ‘warming’ or ‘blanketing’ effect, and without CO2 in the atmosphere, the earth would be considerably colder.
Anyone who simplistically compares solid atmospheric science with “Fred in Bed” has a few problems.
The death pollutant gas carbon dioxide is not a blanket (we don’t live in a greenhouse!!) – rather it slows down infra-red radiation, and in the process of slowing it down (reducing the wavelength) absorbs heat, and transmits that heat to the atmosphere, which in turn heats up the oceans, and leads to the proven Arctic ice melt, death of Polar Bears, and flooding of the poor, who are unable to walk away from the ever-encroaching wetlands in the tropics.
This has been PROVEN science for centuries.
In other words, no matter how good the blanket, a fart still smells like a fart.
It doesn’t matter how limited anthropogenic contributions to CO2 are – the simple fact is that the mere existence of anthropogenic CO2 means that we are all culpable for the imminent destruction of the Earth, no matter how miniscule the anthropogenic assistance.
No matter how much Big Tobacco funds the deniers, the truth of your very own lying eyes puts paid to the denialist arguments. Just look at the freezing conditions climate change has engendered over most of the Northern Hemisphere!
Who cares about the lack of a “hot spot” – not I, as climatology has moved on from that inconvenient truth decades ago.
I first heard about this from the Skeptic’s Handbook:
http://joannenova.com.au/global-warming/
This explanation is much more comprehensive, well-suited for the lay-person and belongs in a mainstream publication. But I guess we’ll file it under “Fat Chance”.
I think this post is slightly misleading. The ‘hot spot’ is supposedly caused by the increase in water vapour as surface air temperature rises which causes a change in the moist-adiabatic lapse rate. It is effectively a feedback effect.
Models show the the same effect regardless of the source of warming.
I don’t think, therefore, that this changes anything regarding the likelihood that CO2 is responsible for recent warming. It might, though, have some relevance in the much disputed feedback debate.
Good explanation of the basic “physics for dummys”, however a major portion of the arguments on both sides revolve around degrees of probability, not a binomial “Yes it is” vs. “No it ain’t”. That is where the layman gets lost, and by default chooses yes or no. Maybe, might be, perhaps, likely, not likely, and other qualifiers indicating degrees of uncertainty on either side simply confuses the issue for the public and results in a conclusion of; “A pox on both your houses”. And don’t even think about presenting the argument in formal notation.
For example; if it were stated that we were “fairly certain” Fred had his blanket on 90% of the time, the resulting explanation would be quite different.
That said, even the scientists involved tend to dislike dealing with probability for a number of reasons including their own ego, personal interest, peer pressure, job/career concerns etc., because they know in their bones that the people who make the decisions want certainty. Or at least a high degree of such. So quite often, a scientist will either consciously or subconsciously inflate his degree of confidence in his results for the reasons given above. And that merely aggravates the issue.
Ron,
To start with, I think the physics in your analogy is wrong. With or without a blanket, when things have settled down, Fred emits the same heat flux to the environment above the bed (maybe a bit less if he was shivering without the blanket). Probably about 200 W. And it convects away from the bed in the same way. Sure it’s warmer under the blanket. But you probably can’t tell much from the pattern above.
As to the disproof of AGW, that may work if you get your facts from the NIPCC (in which case the issue was probably already clinched for you). But if you check the regular science, it’s far less clear. There’s no certainty about the absence of the hotspot. This paper by Thorne et al 2007 gives a summary of the situation.
Reply: The paper is not fully presented, do you have a PDF reference? ~moderator
Thank you Ron House, for a clear and informative post. I’m interested that Kaboom thinks of CO2 as a “death pollutant gas” which leads to death to polar bears and flooding of the poor and that these effects have been known for centuries. (PROVEN SCIENCE) I’d be even more interested to see this proof.
Kaboom (04:29:00) : “The death pollutant gas carbon dioxide”
You are too funny. Trees, wheat, corn, and other plants love it. You breathe it out. Maybe you should ‘disappear’?
Telboy (04:58:05) :
Sarcasm.
looking at kabooms website, i think (hope) he is being ironic
Nick Stokes (04:56:38) :
What happens when the models are tweaked to fit reality instead of the other way around?
And no moderator, the paper is authored almost entirely by the Met Office, so the paper, although published, is too sensitive to release to the unwashed masses. Let them eat cake.
@Nick stokes
Is this the paper where Thorne et al (including Santer) suggested that the error-bars in the observational datasets are so large that they could in theory encompass the model-predicted hot-spot?
I know Kaboom was being sarcastic but can I ask, do the AGW ideas require that the atmoshere warms the oceans? How much energy does it take to heat 1 cubic metre of sea level atmosphere to 15 degrees C. vs 1 cubic metre of say the top metre of the ocean? And how much energy does it take to heat 1 cubic metre of ocean at 3000 metres deep and much greater pressure to 4 degrees C.? Here’s a way out crazy thought. Could the average temperature of the ocean actually determine the average temperature of the atmosphere? If you took the oceans and expanded them until there were the same density of the atmosphere would they have the same “temperature”?
Probably not š Nonetheless I find the idea that the atmosphere heats the ocean a little counter intuitive.
John Finn (04:37:31) :
I donāt think, therefore, that this changes anything regarding the likelihood that CO2 is responsible for recent warming. It might, though, have some relevance in the much disputed feedback debate.
It is this water feedback that makes IPCC models predict catastrophic warming. Absent this feedback CO2 has a minimal effect on the natural climate cycles, which has become evident since 2000 or so with the stasis of heating.
There is the first-order CO2 lab-based heating effect (that’s a given), and there is the hypothesised postive-feedback heating CO2 effect that’s the basis of every GCM.
The lack of a tropospheric HOT-SPOT PROVES that the atmospheric AGW hypothesis is fundamentally flawed. 60 years or radiosonde and 30 years of satellite data offers no escape for the eco-mentalists on this substantial point.
Importantly, and this a killer, the first order lab-based CO2 heating effect may also be undetectable or non-existent because of the multitude of dynamic processes (known and unknown) that is this planet’s climate.
As for the Hidden-Heat Excuse, well it is just that, an excuse. You cannot hide heat in the oceans because the very same oceans will dynamically keep on dumping that heat back into the atmosphere.
Summing up, man-made global warming only exists in people’s heads and in modellers’ computer programs. It is the scientific equivalent of the PC game SimCity.
@Nick stokes
Is this the paper where Thorne et al (including Santer) suggested that the error-bars in the observational datasets are so large that they could in theory encompass the model-predicted hot-spot?
OH! You’re my new favorite blogger fyi
I’m beginning to understand how climate science progresses.
1. A prediction is made by the models.
2. Observations show otherwise.
3. This discrepancy causes data previously considered to be reliable to be suspect. Sufficient analysis and review of the data leads to adjustment of historical data. In this case radiosonde temps need to be lowered a bit.
4. Discrepancy disappears, or at least is no longer significant.
NOAA says “Recent studies, based on the latest information, conclude that there is no inconsistency between climate models and temperature measurements regarding the warming rates of the surface vs. the atmosphere.”
https://www.gfdl.gov/cms-filesystem-action/user_files/jrl/misc/vtt/jrl_misc_vtt_doc-one-pager.pdf
I do note that the language is carefully chosen to avoid saying that measurements actually support or are consistent with the models.
Another examples of how the GCM’s fail to reproduce anything close to reality. Any heat tendng to gather in the swirling upper atmosphere would imeadiatly start escapng to space, and the already saturated GHG molecules would have little effect on the over-all IR heat transfer.
Kaboom (04:29:00) :
I checked out your web site, pretty good parody, especially the acronym
for Conquer Climate Change Permanently!
You have a couple issues that deserve a bit more work.
Clearly, “solid atmospheric science” refers to hailstones, what’s the connection with the hot spot? Are you referring to convective transport of heat upwards?
“slows down infra-red radiation, and in the process of slowing it down (reducing the wavelength) absorbs heat” – if the photons are indeed slowing down, the wavelength will be come shorter, and the light blue-shifted. However, as the radiation goes upward, atmospheric density decreases, so the photons should be accelerating up to the speed of light once they reach the vacuum above the atmosphere. As a non-sequiteur, that’s pretty good. Perhaps you could further confuse the description by referring to the loss of energy as photons claw their way out of the Earth’s gravitational field.
“unable to walk away” – the car-owning rich will become poor as the value of their vehicles heads underwater. Perhaps the Nouveau Poor can reforge them into Greenkayaks and simply paddle away to the greening Sahel in Africa. You can teach the old poor to basketweave their own Greenkayaks from wetland reeds.
Moderator, unfortunately there is a paywall – you can get it from that site at a cost of $9. I don’t know of a site offering free copies.
Mango, yes, the altitude resolution of satellite temperature measurement is not wonderful – this was part of their case.
Telboy (04:58:05) :
I think you’ll find Kaboom was being sarcastic.
DaveE.
“MangoChutney (05:32:54) :
@Nick stokes
Is this the paper where Thorne et al (including Santer) suggested that the error-bars in the observational datasets are so large that they could in theory encompass the model-predicted hot-spot?
OH! Youāre my new favorite blogger fyi”
This wasn’t posted by me – not sure who is the imposter – you may want to remove post
@Nick stokes
Santer also claimed to have discovered the hot spot using the same or similar methods. Santers paper has been shown to be based on noise, so again the hot spot is still missing in action
re: “the altitude resolution of satellite temperature measurement is not wonderful” – Nick Stokes.
To paraphrase “the attitude resolution of blinkered warmists is far less than wonderful.
No Hot-Spot, no AGW.
Having recently read blogs from the non sceptic viewpoint I can only conclude that any variation in climate over recent time supports the computer climate modellng predictions that recent increases in CO2 is ultimately fully responsible for future runaway global warming.
I’m sure WUWT will put as much effort into examining the radiosonde temperature analysis as it has the surface temperature analysis.
REPLY: You mean you want us to photograph and categorize radiosondes measuring temperature in situ?
Ric Werme (05:43:13) :
I particularly like the Carbon Rationing Assessment Program on Kabooms site LOL
DaveE.
Why don’t you do that for us, Boris, since you’re so interested?
Then tell us whether the water heats the air, or vice-versa. From the ARGO site: click
Ron House, Excellent article! Clear and concise. Thanks.
Fred got warmer by disobeying the second law of thermodynamicsāin other words, by magic. Likewise, if someone says heat is being secretly stored somewhere by global warming, despite the absence of the very mechanism that does the warming, they are saying global warming is happening by magic. That is the harsh truth of the matter.
Magic eh, science, magic and religion seem to have interchangeable parts when a political objective is at stake.
This article seems to be confusing the lack of hot spot with hidden-heat-in-the-pipeline, but surely these are two separate issues.
Firstly, the hotspot occurs as a result of increased water vapour from positive feedbacks, not as a result of CO2 forcing per se.
Secondly, the hidden heat argument was floated to account for the fact that air temperatures have apparantly stopped rising even though there is a predicted positive radiative imbalance. The heat was supposed to turn up in the oceans, but this hasn’t occurred since 2003. This is a powerful argument against AGW, but is independant of whether or not there is a hot spot.
The lack of hotspot agrees with Aqua satellite data which has not detected any evidence of water vapour feedback. However, to be fair, this is not evidence that the feedback argument is false, since the warming people keep saying we haven’t reached the tipping point yet. Presumably, they mean that the CO2 hasn’t yet caused a significant enough temperature rise necessary to cause the feedback.
Fred-in-the bed type arguments, as amusing as they are on this blog, are likely to be shredded by the likes of Tamino and Schmidt, and only give ammunition to the alarmists.
Moderator (and Mango)
Here, no paywall, is the later paper by Santer, Thorne et al, specifically taking issue with Douglass et al, which seems to be the guiding hand of the NIPCC section.
Vincent (06:21:16) :
No matter how you slice it, the models did not predict the observed outcome. They are garbage. Admit it.
Kaboom (04:29:00) :
OK, you got me š
“The death pollutant gas carbon dioxide ”
LMAO!!! Hysterical. Good stuff. Keep writing in, I need a good laugh during the day….
**************************************
Nick Stokes (04:56:38) :
Ron,
To start with, I think the physics in your analogy is wrong. With or without a blanket, when things have settled down, Fred emits the same heat flux to the environment above the bed (maybe a bit less if he was shivering without the blanket). Probably about 200 W. And it convects away from the bed in the same way. Sure itās warmer under the blanket. But you probably canāt tell much from the pattern above.
*********************************
The heat signatures of the two scenarios will be different. With or without the blanket after equilibrium has been achieved, there will be the convection heat-induced temperature above Fred. But in the blanket scenario, the area close to Fred will be hotter than without the blanket.
“the climate is constrained by limits that can be understood by any intelligent person willing to learn some simple physics.”
I have a feeling that the only physics that a lot of the AGW crowd ever took was Ex-Lax.
Although the analogy is admittedly simplistic (it is, after all, an analogy), it is interesting to note that it can be extended to encompass additional observational data, i.e., the data from ERBE which indicates that heat loss to space is increasing, just as if Fred had no blanket….
Nick Stokes:
I don’t get how the Thorne et al paper addresses the issue. I thought this paper was along the lines of the Tanaka paper (linked by Anthony Watts here namely, just increase the uncertainty range and then declare the preferred model(s) accurate.
Vincent:
It is not at all clear that the models do not predict a hot spot uniquely associated with human HC emissions. Lucia lundgren tried to track the sources to find what the AGW orthodox position regarding the “hot spot” was.
The performance of the guardians of orthodoxy is pretty slippery on this point. Is it a fingerprint? Do the models say it has to be there? Whoever wrote section 9.2.2 of AR4 seems to think so but the guys at RC are way too smart to get pinned down by a failed prediction–I guess they have some experience in that area. But going from “fingerprint” to a generic “positive feedback forcing from sources of all kinds” still does not explain why the tropical troposphere is not behaving in accordance with the models.
Also, the “tipping point” argument is not consistent with the IPCC models which simply curve upward at a faster rate than CO2 accumulation–there is no step function or magic point. In any event, there would have to be enough warming to get to the tipping point and that would still have to be done per the models.
As for the missing pipeline, the heat is hidden in (a) very windy parts of the upper troposphere (b) somewhere in the deep ocean and/or (c) in vats underneath Dr Evil’s heat-sucking climate lab off the coast of Ecuador (detectable as a big mysterious cold spot on satellite imaging–it’s so obvious, why doesn’t somebody stop him?!!..)
“Any sufficiently analyzed magic is indistinguishable from science!”
— Girl Genius
http://en.wikipedia.org/wiki/Clarke's_three_laws
“Kaboom (04:29:00) :
Anyone who simplistically compares solid atmospheric science with āFred in Bedā has a few problems.
The death pollutant gas carbon dioxide is not a blanket (we donāt live in a greenhouse!!) ā rather it slows down infra-red radiation, and in the process of slowing it down (reducing the wavelength) absorbs heat, and transmits that heat to the atmosphere, which in turn heats up the oceans, and leads to the proven Arctic ice melt, death of Polar Bears, and flooding of the poor, who are unable to walk away from the ever-encroaching wetlands in the tropics.
This has been PROVEN science for centuries.
In other words, no matter how good the blanket, a fart still smells like a fart.
It doesnāt matter how limited anthropogenic contributions to CO2 are ā the simple fact is that the mere existence of anthropogenic CO2 means that we are all culpable for the imminent destruction of the Earth, no matter how miniscule the anthropogenic assistance.
~snip~
Who cares about the lack of a āhot spotā ā not I, as climatology has moved on from that inconvenient truth decades ago.”
“”The death pollutant gas carbon dioxide is not a blanket (we donāt live in a greenhouse!!) ā rather it slows down infra-red radiation, and in the process of slowing it down (reducing the wavelength) absorbs heat, and transmits that heat to the atmosphere, which in turn heats up the oceans, and leads to the proven Arctic ice melt, death of Polar Bears, and flooding of the poor, who are unable to walk away from the ever-encroaching wetlands in the tropics.””
Are you for real?
“Fred-in-the bed type arguments, as amusing as they are on this blog, are likely to be shredded by the likes of Tamino and Schmidt, and only give ammunition to the alarmists.”
Just want to make sure I have this straight. Alarmists can dismiss the 800 year temperature lag by simply saying “just because it didn’t *start* the warming doesn’t mean it can’t at a later time contribute to it and take over.” That’s OK. But Fred-in-bed is just absurd.
Is that about right?
So CO2 is now proven not to be a greenhouse gas because a models predictions are not being met……….
Wattsupwiththat then?
I think Vincent and some others have missed the key point. The question is not about the detailed mechanism, nor is it relevant that a physical blanket uses a different mechanism than atmospheric greenhouse gases. The point is that any physical process has characteristic patterns. Water flowing across land creates characteristic patterns of channels, etc., in the landscape. Seeing those patterns on Mars is evidence of past water. Cars applying their brakes create characteristic skid marks. Seeing them on a road indicates a car applied its brakes. And so on. This point holds for any physical process, and in that sense my analogy is strictly proper, because at no point do I rely on any specific property of the analogy that doesn’t also hold for the real-world atmosphere. It doesn’t matter that the mechanism is different (which I point out in the article).
For the mechanism proposed by the IPCC, their own models predict characteristic patterns of temperature changes in the atmosphere. If those patterns are not observed (and they aren’t) then that model is wrong, regardless of whether they say CO2 did it or increased H2O vapour or whatever. And the hidden heat argument cannot escape this analysis either. Their models result in heating as an outcome of the operation of the hotspot (at least, if the model encapsulates real physics, and if not, why pay attention to it?). To say that the model is working even without part of its essential physical mechanism is indeed to say it is happening by magic. For another example, one might model the stresses in the components of a crane when it lifts a load. If someone claimed a crane was lifting a load whilst there was no stress in its components, they would be claiming it violated Newton’s third law of motion (equal and opposite action and reaction) – that it was working by magic.
Is there some other physically realistic model that still heats the Earth and yet simulates the natural temperature evolution pattern we actually see? Well let anyone who thinks it exists, find it. Until then, it is simply a baseless (yes, really baseless) speculation, certainly nothing one risks the world’s economy and the planet’s climate upon.
I agree that the wrong fingerprint is a very important tool to see that the strengthening greenhouse effect can’t be too important for the changes in the atmosphere, and I’ve used it in all my public AGW presentations, too.
Fred Singer has also counted this observation to be the ultimate disproof, in some sense.
Of course, there may exist issues related to clouds, precipitation etc. that “erase” the fingerprint, much like rain can erase an ink spot, without removing the average warming. But this is a non-minimal theory that would need extra evidence. Climate models with a realistic fingerprint would have to appear first.
Because the observed fingerprint is so structureless, the new climate models would have to confirm some additional data to become more trustworthy than the pretty-much-falsified models used nowadays.
Jim:
“No matter how you slice it, the models did not predict the observed outcome. They are garbage. Admit it”
Well, I am not Gavin Schmidt or Tamino so it makes little difference if I admit it or not. It is these people that need to admit it.
“Santers paper has been shown to be based on noise, so again the hot spot is still missing in action”
Anybody got a link? I’ve been curious about that one.
I don’t think I’d noticed that the predicted hot spot is right where the ITCZ cu-nims are. A warm-spot could never grow there because each day cu-nims would rip it apart.
The essential incompetence of the model can’t handle this.
I think “Climate Scientists” (On “Both” Sides of the Climate Change, Aisle) are the laziest, most incoherent people on the face of the Earth.
Sit around and talk. Sit around and talk. Hypothsize. Theorize. Anything to keep the money flowing. But, NO Experiments.
You want MY “vote?” Show me. Do an Experiment.
First, you build “two” greenhouses . . . . . . . . .
Ron House (07:08:39):
Don’t worry, most of us actually read the article and understood exactly what you were saying. I think it says a lot about cognitive dissonance when you read some of the replies that attempt to attack the poor little Fred himself (ie. the details of the analogy).
I would expect RC and Tammy to do the very same thing. Attempts at logic, when embraced by those with severe cases of cognitive dissonance, can result in some very illogical statements.
A few days ago I saw on WUWT a graph showing the amount of infra-red heat retention versus the CO2 concentration. It showed, as I recall, that the heat retention maxed out at about 400ppm and that above this CO2 concentration the heat retention didn’t increase very much. So, in other words, using the Fred analogy, you can go piling blankets on Fred but after a certian number of blankets Fred is not going to get any warmer.
Link to research: http://arxiv.org/ftp/arxiv/papers/0905/0905.0445.pdf
“An updated comparison of model ensemble and
observed temperature trends in the tropical troposphere”
Stephen McIntyre(1), Ross McKitrick (2)
Abstract
A debate exists over whether tropical troposphere temperature trends in
climate models are inconsistent with observations (Karl et al. 2006, IPCC
(2007), Douglass et al 2007, Santer et al 2008). Most recently, Santer et al
(2008, herein S08) asserted that the Douglass et al statistical methodology
was flawed and that a correct methodology showed there is no statistically
significant difference between the model ensemble mean trend and either RSS or UAH satellite observations.
However this result was based on data ending in 1999. Using data up to the
end of 2007 (as available to S08) or to the end of 2008 and applying exactly
the same methodology as S08 results in a statistically significant
difference between the ensemble mean trend and UAH observations and
approaching statistical significance for the RSS T2 data.
The claim by S08 to have achieved a āpartial resolutionā of the discrepancy
between observations and the model ensemble mean trend is unwarranted.
Duplicate – But perhaps this version flows a bit better onto the site?
Link to research: http://arxiv.org/ftp/arxiv/papers/0905/0905.0445.pdf
āAn updated comparison of model ensemble and
observed temperature trends in the tropical troposphereā
Stephen McIntyre(1), Ross McKitrick (2)
Abstract
A debate exists over whether tropical troposphere temperature trends in climate models are inconsistent with observations (Karl et al. 2006, IPCC (2007), Douglass et al 2007, Santer et al 2008). Most recently, Santer et al (2008, herein S08) asserted that the Douglass et al statistical methodology was flawed and that a correct methodology showed there is no statistically significant difference between the model ensemble mean trend and either RSS or UAH satellite observations.
However this result was based on data ending in 1999. Using data up to the end of 2007 (as available to S08) or to the end of 2008 and applying exactly the same methodology as S08 results in a statistically significant difference between the ensemble mean trend and UAH observations and approaching statistical significance for the RSS T2 data.
The claim by S08 to have achieved a āpartial resolutionā of the discrepancy between observations and the model ensemble mean trend is unwarranted.
ā. . . although the actual mechanism is different, something is ākeeping the heat inā . . .ā
Letās do away with the blanket concept and explain how the CO2 molecules interact with āwaves/rays/photons/energyā to warm the Nitrogen, Oxygen, and Argon that constitute the huge mass of the atmosphere, the H2O of the oceans, and the materials of the landās surface.
This issue may need a little more than āsimple physicsā but why not give it a try, anyway? Iāve read here on WUWT and elsewhere that CO2 reaches its potential āwarming abilityā at about 10% of its present-day concentration and really canāt perform much more than that, thus needing a 300% (or so) multiplier from some mechanism (+feedback), as yet unknown.
A greenhouse works because the enclosure shuts down the fundamental process of the troposphere āconvection, where warm air rises. āGreen House Gasesā do not do that, so please explain what they do do, with enough physics so I can check your work? Thanks.
It makes me feel sad: Poor little Jimmy H lost his piggy bank where to imagine saving his warmed pennies…let’s get him another.
dorlomin (07:04:49) :
So CO2 is now proven not to be a greenhouse gas because a models predictions are not being metā¦ā¦ā¦.
—————————————
Now that is one seriously ugly straw man
“So CO2 is now proven not to be a greenhouse gas because a models predictions are not being metā¦ā¦ā¦.”
Incorrect. What the data shows is there is no positive feedback from water vapor, and therefore no astronomical warmup on the way. CO2 is still a greenhouse gas, just one that has no more punch left…
Ron House (07:08:39) :
If those patterns are not observed (and they arenāt) then that model is wrong, regardless of whether they say CO2 did it or increased H2O vapour or whatever
It doesn’ t matter if it is right or wrong. It is a CREED in which we are suppose to believe, it is a matter of having FAITH!!
And…they got the money, they got the power, they are the ones….(to be taken to the asylum).
Thank you Ron House for an explanation a lay person like me could understand.
And Thank you to Anthony for running this website
Ya know…before armageddon a sign will appear in the sky…all prophets agree, from JH to AG the sage.
“Ladies and gentlemen, I present The Emperor’s Blanket! Isn’t it beautiful?”
The presence of CO2 is a signature of greed. That’s the signature greenies are really thinking about. If we can tackle that mistaken perception, then we can all go home.
Patrick Davis (07:02:29) So you are saying that what Fred needs it is a bottle filled with hot CO2 to warm his feet instead of hot water!!!
Air does not holds heat as water does: It saves warm 3227 times less than water.
But, of course, you have the right to believe that there is something up there in the sky shining, as a sign, before it falls down on our heads. (as your prophets told you for sure)
Suppose Fred urinates in bed. The stored up heat leaving the pipeline now interacts with the air under Fred’s blanket. Could this be an analogy of a “tipping” point, whereby the runaway warming process would begin once morning dawns and Fred rises from bed?
Sorry, I have to be as skeptical of this explanation and analogy as I am as to the claim that a spaceblanket will keep you warm. I spent a night shivering under one of those darn things. How are we supposed to through the radiative, convective, and conductive processes?
Ron,
One final question about the missing fingerprint. This appears to have been addressed in a paper entitled “Consistency of modelled and observed temperature trends in the tropical troposphere” by Santer et al.
https://publicaffairs.llnl.gov/news/news_releases/2008/NR-08-10-05-article.pdf
They are saying that the inconsistency was due to using older radiosonde and satellite datasets and 2 methodological errors.
Based on this paper there appears to be a standoff. One side says there’s no fingerprint and the other says, oh yes there is. How do we resolve this and move forward?
We don’t know if there is a “fingerprint” above, but by DNA studies and our own experience as investigators we know who is the culprit.
Please don’t put posts like this on WUWT. The blanket analogy is simple BUT misleading and wrong and does not reflect well on a website that usually publishes decent and thoughful comments on science.
The lack of a hotspot does indeed show that the models are failing to model the real world with accuracy but this doesn’t prove anything about AGW .. it just shows the models are bad models.
I have no specific science training apart from some electronics. I have never believed in the AGW theory simply because I have lived and worked for many years in desert countries.
Summer daytime temperatures often exceed 40C but temperature by next dawn could easily drop below 10C. Definitely no “blanket” effect. Of course we didn’t know about AGW in those days. We only seemed to record daytime maxes.
Maybe somebody could post some desert temperature ranges for clear air max/mins and also for cloudy periods for comparison.
– I find the analogy in this article incomprehensible – and I am certainly no AGW-er. It seems to me that the last thing we should be talking about to explain the GHG effect is a blanket. The IR-hotspot analogy is not applicable IMO.
– The terrifying colors in the first of the two graphs represent ‘total linear CHANGE over 1958-1999’ according to the scale. The colors of the second graph represent ‘linear trend Ā°C/decade’, whatever that is (no timeframe either).
What is being compared with what here?
Given the sloppiness we get from the AGW-ers, I think we should try and hold ourselves to a higher standard on this site.
…and the two graphs have different temperature scales – tut, tut.
Vincent, this has been resolved already: http://www.climateaudit.org/?cat=129
Santer claimed these two curves – http://blog.sme.sk/blog/560/195013/tropictrends.jpg – are basically the same, but even the last traces of flawed statistics disappeared when whole interval was used for testing, not just till 1999 as he deliberately did.
Actually, there is no proof of increased “greenhouse” effect: no hotspot, no decrease in outgoing IR radiation (which should occur if the “blanket” gets thicker). Even upper tropospheric water shows decrease during the last decades, which hints the opposite, but whether it is a response of self-regulating mechanism against increasing CO2 (per Miskolczi) or against strong solar cycles (this match for relative humidity 300-700mb is remarkable), nobody knows yet.
Richard111 (10:17:29) : Maybe somebody could post some desert temperature ranges for clear air max/mins and also for cloudy periods for comparison.
That is a very good idea: real data from real environment.
Curiousgeorge (04:54:57) :
people who make the decisions want certainty
Are you sure?. Is it not the contrary?
I can accept it happens in private businesses but neither in any government nor in show business whatsoever. If it scares, distracts or even fools, or…whatever , it’s OK
The difference is, Fred’s body generates quite a lot of heat of its own, regardless how it disippates when he sleeps. The earth however radiates a tiny fraction of the heat budget – some 1% of the “heat budget”. Even if c02 could trap longwave radiation, there’s precious little of it to hold onto.
http://nov55.com/41r.html
“The IPCCās reports are based on results from a collection of climate computer models; they have nothing else”
That laughable statement tells me straight away that you’ve never read any IPCC reports.
“”” Phil M (04:27:58) :
Equally, I donāt think there are many people who dispute that CO2 in general has a āwarmingā or āblanketingā effect, and without CO2 in the atmosphere, the earth would be considerably colder. “””
Solar energy arrives at earth at a roughly constant rate; 1366 W/m^2, which would continuously increase the temperature of the earth; BUT ! the earth also radiates energy in the infra-red spectrum, which could escape from the planet in one millisecond. If a “blanket” mechanism slows the exit of the IR radiation; but does not affect the incoming solar energy, then the delay in the exit, will result in more incoming solar energy, so the temperature would rise by some increment; to re-establish an “equilibrium” exit rate. (unless something else happens)
One of the something elses that may happen would be simply an adjustment to the amount of global cloud cover. An increase in cloud cover would block more sunlight and that could compensate for the blanket. So it is not a foregone conclusion that the existence of a blanket results in significant temperature rise.
Nor is it necessary that the earth be much colder in the absence of CO2. Water vapor is a much more powerful “blanket” gas than CO2, and there is plenty of water to substitute for any deficiency in CO2 blanketing.
Absent the CO2 and the water would simply adjust the water vapor and cloud cover to adjust the temperature. The earth’s temperature is primaril;y a direct result of the the physical properties of H2O. Other variables may change; but so long as the water is there in the oceans; and forms clouds in the sky, the temperature can’t mpove out of a fairly small range; dependent on the properties of water.
Kaboom, what nonsense you speak.
Infra-red travels at the speed of light; always does; CO2 doesn’t change this.
Polar bears are doing just fine, more around today than for the previous 50 years.
You’re quoting the NIPCC who utilise out-of-date information. The raw radio sonde data contain numerous (until recently) uncharacterised errors and discrepancies due to different methodologies. I would recommend familiarising yourself with the latest available literature which shows that model vs radio sonde discrepancies have largely been resolved. Also, there are other datasets available to look at trop. trop. temperatures: RSS and UAH. Your analysis is simply too narrow given the well known discrepancies in the CRU trop. trop. radio sonde product.
http://earth.geology.yale.edu/~sherwood/sondeanal.pdf
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F2008JCLI2287.1
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F2008JCLI1929.1
https://publicaffairs.llnl.gov/news/news_releases/2008/NR-08-10-05-article.pdf
Well, there IS a blanket effect, but it’s much less pronounced when the blanket (water vapor) is much thinner, as it is in deserts.
Kum Dollison (08:04:03) : “Sit around and talk. Sit around and talk. Hypothsize. Theorize. Anything to keep the money flowing. But, NO Experiments.
You want MY ‘vote?’ Show me. Do an Experiment.”
Well, that’s just the problem, isn’t it? We can do experiments (add carbon dioxide to the atmosphere, clear a jungle, vary the sun a bit, blow the occasional volcano, pour soot into the air, move the continents), but we can’t do controlled experiments, e.g. build a hundred earths and change one thing on each.
Climate science isn’t really an experimental science; this situation is known as “job security”. š
P Wilson (10:59:06)
‘The earth however radiates a tiny fraction of the heat budget ā some 1% of the āheat budget”‘.
Sorry, but as far as I understand the situation, the Earth is an object in space receiving energy from the Sun. As with any other body, the Earth will heat up until it’s temperature causes it to radiate the same amount of energy into space and an equilibrium is achieved.
What is this ‘heat budget’?
Sorry to be so combative – must be something I’ve eaten…
How would ITCZ cu-nims affect this predicted hot-spot??
Can we repeat this analogy with Bill, Sid and Joe – so we have more data?
Colin Aldridge (09:52:54) :
Please donāt put posts like this on WUWT. The blanket analogy is simple BUT misleading and wrong and does not reflect well on a website that usually publishes decent and thoughful comments on science.
The lack of a hotspot does indeed show that the models are failing to model the real world with accuracy but this doesnāt prove anything about AGW .. it just shows the models are bad models.
But the models are one of the key aspects to AGW. If the theory is incorrect, how likely is it that GHG’s are the cause of recent warming? Admittedly, this is hard to gauge. But it does show us that the experts really don’t know what they are talking about.
“āGreen House Gasesā do not do that, so please explain what they do do, with enough physics so I can check your work? Thanks.”
Happy to oblige.
The basic mechanism is described in Soden and Held [1], which was cited by the IPCC TAR (iirc). It is a combination of two effects – that its temperature changes when you compress or decompress a gas, and that equilibrium occurs when the heat input from the sun equals the heat output from the average altitude at which the atmosphere radiates to space.
Air pressure decreases with altitude, which means that so long as convection drives the rise and fall of air, it will be compressed and decompressed, resulting in a vertical temperature gradient in which it is warmer at the bottom than the top. Everybody knows that hot air rises, so it at first seems surprising that mountaintops are cold. It’s called the adiabatic lapse rate, and is standard physics that can be found in many textbooks.
The other effect is that the radiated heat increases with temperature, so if there is a heat input, the temperature will rise until it reaches the point where the heat emitted from the radiating surface exactly equals the input. But because of greenhouse gases – mainly water vapour – this is not the solid surface, but a foggy one extending throughout the lower troposphere, averaging out at about 4 km up. It is therefore the point 4 km up that settles out at the radiative equilibrium temperature, and then the air above and below it is respectively cooler and warmer because of the moist adiabatic lapse rate.
This is important. The surface is not warmer because heat is “trapped”. The warming mechanism is pressure, not absorption. And more greenhouse gases mean a thicker layer of IR-opaque ‘fog’, a higher average emission altitude, and therefore a greater pressure difference between this altitude and the surface.
And the check on the physics is that the atmosphere above the average emission altitude is colder! The temperature at the top of the troposphere drops to -54 C. There is no way to explain that with a “blanket” model.
Everybody gets the explanation wrong. (Which is positively shocking after 20 years at the top of the apocalypse charts!) I don’t expect anyone to start getting it right now as a result of me explaining it. š
[1] Water Vapor Feedback and Global Warming, Annu. Rev. Energy Environ. 2000. 25:441-75.
In the case of AGW, all the Global Climate Models(GCMs) and the AGW CO2 theory predicts that there should be a measurable hotspot in the upper troposphere. Observations from satellites and weather balloons have been made, and no hotspot has been found.
That about right?
In a less politicized field, this would have been the end of it. If it weren’t for the hoaxer’s grant money, the real scientists would have long moved on.
The law of conservation of energy is certainly taking a beating in this post. Having lasted a couple of centuries, however, it will probably survive the present onslaught.
George E. Smith (11:17:31)
‘Solar energy arrives at earth at a roughly constant rate; 1366 W/m^2, which would continuously increase the temperature of the earth; BUT ! the earth also radiates energy in the infra-red spectrum…’
[At a large range of frequencies, not just IR]
‘…which could escape from the planet in one millisecond.’
[Let’s let that pass…]
‘If a āblanketā mechanism slows the exit of the IR radiation; but does not affect the incoming solar energy, then the delay in the exit, will result in more incoming solar energy, so the temperature would rise by some increment; to re-establish an āequilibriumā exit rate. (unless something else happens)…’
How does this blanket ‘slow anything’? If molecules in the atmosphere absorb energy their energy state – i.e. temperature is raised. They are then more likely to emit energy in some form.
Considered as a body, the Earth is thermodynamically the sum of the solid bits, the wet patches and the gassy envelope. The ‘blanket’ behaves just as thermodynamically as the Earth. To return to the inappropriate analogy in the original post, it is true that the blanket stops warm air convecting away from Fred during the night, but the blanket itself warms up and radiates and conducts heat to the outside. If Fred were not generating his own heat, he would soon return to ambient temperature, with or without the blanket, as any ‘CSI’ viewer will tell you. If you wrap a blanket round a rock, it’s temperature won’t rise.
Don’t forget: the hottest bit of the atmosphere is the thermosphere – on the edges of space.
Colin Aldridge (09:52:54). Blankets… hear, hear!
… its temperature … sorry.
Perhaps the kind moderator will correct it!
I didn’t have time to read all the comments, but it seems like a lot of you missed the point: If the models predict something and it’s not there, then the models are wrong.
Fred & a blanket (or not) is just a way of making the point.
John Finn (04:37:31) :
You and I both know that the( MSM and Joe the Citizen) are going to buy Fred in Bed over adiabatic time-lapse rate feedback.
They are especially going to buy Fred in Bed when Fred has to use more blankets than last year They have not forgotten last winter, bet on it. They have also not forgotten the wrong calls made on the seasonal forecasts. Don’t try to sell them an El Nino before it happens.
The attention span of Fred the Citizen won’t give you the hour-long explanation necessary to explain adiabatic. The weather report is short, and for good reason. That’s all that really matter to them, plus a couple of words about next week and the next season when appropriate.
The “hot spot” is created in the models by assuming a strongly positive feedback over the equator due to a warming sea. This is clearly wrong, observation demonstrates that, and that is why the models predict something that is not observed.
If they were to model the climate with a neutral or negative cloud / watervapour feedback as occurs in reality, the models would then correctly predict what is observed with radiosondes / satellites. But then the silly claims of 4-7 degrees would drop to 0.1 – 0.3 degrees, which would generally be beneficial (Idso calculates a co2 sensitivity FROM OBSERVATION rather than a model of 0.4 for a doubling of pre-industrial, hence 0.1 degrees of warming to come).
The “blanket” is there, the question is how thick is the blanket and how warm will it make fred, is the blanket to thin its hard to observe? Observation tells us that the blanket is thin as does little to warm him, there is no thick section of blanket over his torso making him snug and toasty and no “hotspot”!
The warming in the pipeline comment is a great point, the warmth can not hide in the sea, the air would have to warm first in order to warm the sea! The heat can not just jump straight to the sea from the upper troposphere, thats rediculous, and besides the sea is not warming!
Its a great, though simplistic, explanation, but needs to clarify what the hotspot is and why the models fail in this area. It is not due to co2 directly, but the assumed positive feedbacks.
In climate models the sun also causes the same “hotspot”.
Juraj V,
Thanks for the links. This is fascinating stuff
one haevy mistake!
the body you show (fred), is a heat engine. the time you use is too short to explaine the atmosphere with the earth. lets fred die, and kalkulate again…
and now think ist over: isnt it only a faktor of time?
Glug,
Thanks for the links.
http://ams.allenpress.com/perlserv/?request=get-abstract&doi=10.1175%2F2008JCLI2287.1
This one above seems to be saying that the observed data does not agree with the models.
The last link is for the Santer et al paper I’ve already mentioned. There does seem to be a number of issues with this. McIntyre is writting a paper to discuss these issues. Should be interesting
P Czerna: sorry i meant to write “re-radiates”, and not radiates. The heat budget is the amount of solar energy received by the earth minus the amount of heat lost by the earth over a given time period.
Tarpon 12:17 “all the Global Climate Models(GCMs) and the AGW CO2 theory predicts that there should be a measurable hotspot in the upper troposphere. Observations from satellites and weather balloons have been made, and no hotspot has been found.
That about right?”
Not quite. If the observations had fit the model, that would be the end.
But the observations don’t support the model, so a search begins to find the error in the observations. The radiosonde data is found to be on the high side; and the estimated error of the observations were found to have been underestimated. With the past tropospheric temperatures revised downward and the uncertainty of the measurement increased, it now appears that the observations (although not fully supporting the model) are not sufficient to reject the model.
The same sort of sequence has taken place in the Ocean Heat Content projections and Argos buoy data. Read how NOAA saved the world’s oceans from a cooling trend: http://earthobservatory.nasa.gov/Features/OceanCooling/ , “Correcting Ocean Cooling”. The article is a bit off topic, but it shares the same confirmation bias theme as the history of the hot spot.
We have behaved so bad that CO2 has increased in such a proportion as to provoke the opposite, an ice age, we have no time at all, all nations should start buying windmills NOW ! (bribing not allowed).
Kaboom (04:29:00) :
The death pollutant gas carbon dioxide is not a blanket (we donāt live in a greenhouse!!)
I just finished a bottle of some kind of carbonated drink called “Fernandez”, its damn tasty and you tell me that the CO2 in it is a deadly pollutant? OOOOOH MY GODDESS i am going to die.
BTW: Photons always travel at lightspeed, its that the keep bouncing into atoms and have to ask the way out again that slows them down.
I am a skeptic of AGW and do have a large problem with the IPCC’s work. So what I say here refers to the misuse of the two figures. I have seen these two figures so compared before. But, I am afraid the user overlooks the respective scales and thus makes too much regarding the differences. The modeled data is for a period of 41 years; the scale is C/41 years. The HadAT2 data is for C/decade, or C/10 years. Taking this into account then the hot spot in the modeled data reduces to a range of values from 0.25 C/10 years to 0.3 C/10 years. The HADAT2 data places the values from 0 C/10 years to .1 C/10 years. The ratio of these is ‘3’ for the upper end. So, even though there is a difference between modeled and observation we should be cautious in making too much out of this.
What if Fred’s blanket is infinitely thick?, then, and only then, greenhouse would be possible. (If Fred is infinitely robust, of course)
Stevo (12:15:57) : Happy to oblige.
OK, now to the core of my question. Say, I have a molecule of CO2 and it is in Earthās atmosphere. Next our Sun sets a packet of energy traveling in Earthās direction and some meters over my head energy meets molecule. Or not. So, much of the energy comes to Earthās surface. Maybe it is reflected. Maybe it is absorbed. The absorption transforms the solar energy into molecular motion which gets measured as a temperature increase. Now the surface radiates from a lower temperature, than does the Sun, with a longer wavelength and the energy heads away from the surface ā where it might have an encounter with a molecule of air, even, perhaps, CO2.
Usually, at about this point someone says ā. . . and the atmosphere warms because CO2 acts like a blanket.ā
Sorry, that wonāt do. I want to know what happens next. Your answer should explain what CO2 does and why, and why N2 or O2 donāt do āthisā, whatever āthisā is. In the end, whatever āthisā is, it is supposed to warm the atmosphere.
Your reliance on āThe warming mechanism is pressure, not absorption.ā ā Seems to sidestep the entire notion of why GHGs are involved at all.
Then you have this: āAnd more greenhouse gases mean a thicker layer of IR-opaque āfogā,ā
Do you actually mean there is a layer ā Iāve seen diagrams with such layers ā or do you favor a well dispersed mixture of molecules?
Is the atmospheric pressure at sea level greater at present than it was in the year before the industrial age began?
rbateman,
It took you an hour to read that?
Well, ok, here’s a faster explanation. Greenhouses gases aren’t a blanket, they’re a refrigerator. Kitchen refrigerators pump heat from the inside to the outside. The one in the atmosphere cools the top of the atmosphere and pumps the heat down to the surface. And because the thermostat is positioned half way up the fridge, the bottom is warmer than expected given the number on the dial. That extra warminess is called the greenhouse effect.
Fred’s blanket is assumed by the models to act as a diode. The energy comes in, but the heat (IR) can’t get back out.
Fred is a good model. The Earth likewise is heated internally by tidal forces of Sun & Moon gravitational tug-of-war acting in equal force by way of distance scale and in constant state of vector change.
The models predicted increased heat retention assuming that Fred’s blanket is 100% effective in thier calculations, and blew off any change in the thermostat that heats Fred’s room at night. The only thing wrong with Fred is that his diet is not 100% constant.
The amount of heat coming from the Sun is not constant, and neither is the atmosphere’s retention rate linear as regards the trace gas CO2. So they changed thier models. They still have it 95% wrong.
I could say the same thing about the Sun & Solar System’s evironment as regards the Galaxy, but I’ll wait.
We can do an experiment actually. Put 350ppm of c02 in a chamber and 600ppm in an identical chamber. Subject them to the same heat source for 30 minutes at 30C.
According to the AGW advocates, the 600ppm ought to be 34C whilst the 350ppm chamber would be constant 30C, in theory. It raises the question: Where did this extra 4C come from?
Stevo: Ijust had an email from teh Met Office here in the UK in response to a question as to why temperatures plummetted during the solar eclipse. They categorically replied that “C02 doesn’t retain heat. It intercepts and transfers heat to the atmosphere” Therefore, despite c02 being the great climate driver, it tells the heat to go elsewhere, since c02 doesn’t seem to like absorbing heat.
Fill a closed test tube with a known amount of CO2 gas, heat it up using an infrarred bulb, take the time it takes to cool down (in nanoseconds of course).
Stevo (13:52:44) :
rbateman,
It took you an hour to read that?
It will take an hour to EXPLAIN that to Fred the Citizen, and you have about 5 minutes top, after which all subsequent explanation will fly over the head of Fred.
Fred doesn’t do heiroglyphic scientific paper reading.
Fred will stop you after 30 seconds for the definitions of words never heard before.
At that point, it’s all downhill.
Couple of spins in Fred’s head over a highly confusing picture and you’re done.
Fred will excuse himself.
I guess i’ll be adding c02 to my bedroom if my heating breaks down this winter…
or better still, just open the window and let it diffuse in from the cool air outside
John F. Hultquist,
The photon hits the solid surface and is absorbed. It’s actually irrelevant how the heat escapes to the middle/upper atmosphere – some does so by IR radiation, some by convection, some by evaporating water from the surface (like sweating cools you). The only thing that matters is that because greenhouse gases can absorb and emit IR, that at least some of the emission to space is from altitude.
The reason why H2O and CO2 absorb/emit is that their molecules are asymmetrical. Some bits look different to other bits, and in particular have a different electrical charge, which means electromagnetic waves have something to ‘grab on to’. N2 and O2 are ‘all the same’, so the forces cancel out exactly.
It would in fact be possible to have a greenhouse effect without any greenhouse gases at all. Imagine a fictional alien planet that has a very thick Nitrogen atmosphere and a high level layer of dusty clouds, that absorb and re-emit nearly all of the light of the sun. The cloud layer settles out at the equilibrium temperature, such that it emits exactly as much heat as the planet absorbs, and just enough light gets through the clouds, reaching the surface, to drive convection. Then as gas descends from the warm cloud level down to the surface, it is compressed and gets hot. And then as it rises again it expands and cools down. If the atmosphere is thick enough, the surface could be intensely hot. A 50 km thick atmosphere with a 10 C/km lapse rate would be 500 C hotter than the clouds above. And with not a greenhouse gas in sight.
All that matters is that some of the emission is from above the surface, so the average altitude of emission is greater than zero; and that enough energy reaches the surface to drive convection. Without convection, the temperature gradient reverses, with warm air on top of cold, and there is no exchange between layers to drive the changes in temperature.
The fundamental reason they matter in the Earth’s atmosphere is that they change the average height of emission – moving the ‘thermostat’ upwards. All that matters is that they emit. Absorption is just an equivalent physical property. But even if you could invent some impossible material that emitted without absorbing, the heat would still rise by convection, evaporation or even conduction to the emitting layer and it would still show the same effect.
Nearly all of the emission to space comes from the bottom 8 km, with a nearly uniform spread over that altitude, so some of it comes from colder air and some from warmer – and of course there’s some direct from the surface, which is what the satellites pick up. That’s simply because that’s where the water vapour is. It evaporates from the surface, and condenses out when it gets too cold, so that above a certain altitude the air is intensely dry. If you want the exact profile, see Manabe and Strickler, J. Atmos. Sci. 21:p373 (1964).
roddy.baird (05:27:49) :
“Nonetheless I find the idea that the atmosphere heats the ocean a little counter intuitive.”
Roddy, as I understand it if something is warmer than something else then given the opportunity heat will travel downhill, and heat will not distinguish between solid, liquid or gas. As an example in the UK we are subject to about 5 different types of air mass (excuse if you know already), and is either dry, wet, hot, warm cold etc. and all because that air has passed over something dry, wet, hot, etc. etc. It might not be much, but if air passes over water that is cooler than itself then the air will become a little cooler and the water a little warmer. Of course once that air gets here then depending on prevailing conditions the land will either add or subtract heat or moisture. I haven’t forgotten the sun. It’s just for us in the UK to have a nice day down the beach we need the air to come from somewhere warm and dry, and not too fast, and then the sun can get to work.
“no matter how good the blanket, a fart still smells like a fart”
You know the honeymoon’s over when the husband pulls the blanket over his spouse’s head after he’s farted in bed.
***********************
Stevo (12:15:57) :
This is important. The surface is not warmer because heat is ātrappedā. The warming mechanism is pressure, not absorption. And more greenhouse gases mean a thicker layer of IR-opaque āfogā, a higher average emission altitude, and therefore a greater pressure difference between this altitude and the surface.
**************************
OK, I’ll bite. So you add 200 ppm to the atmosphere. The average emission altitude goes up. So what? The extra 200 ppm of CO2 won’t add any significant pressure due to the extra gas. If you are saying the extra CO2 will heat the air and thereby increase the pressure, OK. So you add the CO2, increase the pressure, the air get hotter and re-equilibrates. That is, the heat caused by the increase in pressure dissipates and the air cools off. For example, if I turn on my compressed air machine. It gets hot as the pressure goes up. But after the pressure ceases to increase, it cools off again.
Someone could repeat the Wood experiment: http://neighbors.denverpost.com/blog.php/2009/02/04/greenhouse-theory-disproved-a-century-ago/
************
Stevo (14:39:09) :
All that matters is that some of the emission is from above the surface, so the average altitude of emission is greater than zero; and that enough energy reaches the surface to drive convection. Without convection, the temperature gradient reverses, with warm air on top of cold, and there is no exchange between layers to drive the changes in temperature.
******************
Why doesn’t the convection upwards take away as much heat as was deposited by the sinking gas?
OK, this is what I do not understand and I would appreciate someone explaining for me.
Question 1. There are numerous graphs, pictures out there , related to GW that depict temperature anomalies. So we have somewhere up in the atmosphere that is 2C warmer than it used to be. For a standard atmosphere of 15C lets assume at around 10,000ft it has warmed from a supposed usual of 0C to 2C. The question is can this extra heat warm the surface?
Question 2. CO2 is considered to have a greater affect (heating wise) at altitude. Considering CO2 is distributed evenly at around 360 ppm what consideration is given to the actual amount per volume? e.g at 10,000 there is a third less atmosphere for a given volume. So whereas at sea level there might be 360 CO2 molecules in a given volume, at 10,000ft there is only 240 CO2 molecules for the same volume, and at 35,000ft there is a measly 1/5 or around 70 CO2 molecules.
“”” Stevo (14:39:09) :
John F. Hultquist,
The photon hits the solid surface and is absorbed. Itās actually irrelevant how the heat escapes to the middle/upper atmosphere ā some does so by IR radiation, some by convection, some by evaporating water from the surface (like sweating cools you). The only thing that matters is that because greenhouse gases can absorb and emit IR, that at least some of the emission to space is from altitude.
The reason why H2O and CO2 absorb/emit is that their molecules are asymmetrical. Some bits look different to other bits, and in particular have a different electrical charge, which means electromagnetic waves have something to āgrab on toā. N2 and O2 are āall the sameā, so the forces cancel out exactly. “””
So just what is it about CO2; and how about CH4, that is assymmetrical. Explain how this assymetry is any different from the assymetry of O2 and N2.
So a sphere is symmetrical; but what else is ? And that too is irrelevent since spheres do not exist anywhere in the universe.
Out of interest and related to the temperature cross sections. I watched a DVD of Concorde on a round the world trip. As Concorde crossed the Pacific it was pointed out that Concorde was able to go further and higher because of the colder equatorial air at altitude. It was not a surprise. It was expected and planned for.
Where the IPCC is in error is on the 4th power lapse of infrared radiative forcing. The 1st power of course, is the solar energy reaching the earth which c02 is invisible to. The 2ns is re-radiation to the tropopause (1-3% of the original energy budget) The 4th power is the re-radiation back to the earth from the tropopause downwards and upwards – absorbed radiation is re-emitted bi directionally – so we can assume that 50% of withheld radiation goes back into space – In other words, thermal re-emission beyond the tropopause – whilst the other 50% does in fact go back to the earth. From 1-4 there is a huge energy loss. No additional energy is re-introduced during this process, so it can be assumed that the coefficient of solar energy is the dominant factor. The IPCC assumes that the ratio isn’t 1:1 even but entirely downwards, which is the first fundamental mistake. So when warming projections looked exagerrated, they assumed that it was a cooling effect from aerosols. What they are also ignoring is the strong water vapour feedback – it also witholds heat at 15Mc’s and many other wavelengths – far more than c02, and given that from the tropopause to the earth is where water vapour resides, it effectively means that there is less radiation for c02 to absorb. Efectively, the water vapour feedback neutralises the c02 feedback, and climatically they are both feedbacks and not forcings, and are dependent on atmospheric temperatures. This is the case for all c02, and not just the 3% anthropogenic
***********************************
Stevo (12:15:57) :
This is important. The surface is not warmer because heat is ātrappedā. The warming mechanism is pressure, not absorption. And more greenhouse gases mean a thicker layer of IR-opaque āfogā, a higher average emission altitude, and therefore a greater pressure difference between this altitude and the surface.
*****************************************
Stevo – what you have said is interesting. If you would suffer one more questsion. I thought sunlight mostly passed through the atmosphere and was absorbed by the surface of the Earth, including the oceans – even there it eventually goes dark at some depth. So the sunlight is absorbed and heats the Earth. I thought that is why the surface of the Earth is hot. Again, why do you say it is pressure?
Time to refer to my highly relevant article here:
http://climaterealists.com/index.php?id=1562&linkbox=true
“Greenhouse Confusion Resolved.”
This essentially shreds the notion of positive feedbacks. Conversely, it suggests where the next round of research should focus, namely, understanding negative feedbacks.
I guess an issue with refuting the hot spot by analogy is that, in dissipative and conservative systems the variables of gravitational acceleration, the specific heat at constant pressure of dry air, the gas constant for dry air, the mixing ratio of water vapor, the latent heat of vaporization, the ratio of certain gas constants, temperature and spontaneous and unpredictable aspects such as the irreversible moist-adiabatic process can combine. Yes?
However, to be fair, this is not evidence that the feedback argument is false, since the warming people keep saying we havenāt reached the tipping point yet.
I’ll bet the waitresses hate that.
Since this is our first instance of global warming where computer models and modern knowledge of thermodynaics is widely available, isn’t the hot spot essentially an untested hypothesis?
So we shouldn’t read too much in to the lack of a hot spot, the theory is still uncharted territory.
Vincent,
“model vs radio sonde discrepancies have largely been resolved”
I qualified that statement for a reason. Some discrepancies remain. The updates mentioned in Lanzante’s work go beyond the sonde analyses quoted in the NIPCC report i.e. HAD AT2. The NIPCC is quoting out-of-date material, IMO. The discrepancy is largest in the NIPCC report due to their data selection choices. The discrepancy is somewhat resolved in Lanzante’s work though by no means completely. The other studies seem to resolve this issue further.
“McIntyre is writting a paper to discuss these issues.”
McIntyre is submitting a comment on this paper highlighting that the inclusion of more years of data breaks one of the hypothesis tests with respect to UAH data. This is a useful contribution and not entirely unexpected given that RSS and UAH are somwhat divergent. Did his analysis go beyond this? Perhaps you can correct me if I’m understating his result. According to Santer et al., UAH and some of the older sonde products seem to be showing the greatest remaining discrepancies. NIPCC use the oldest, coolest trending and most widely acknowledged to be the most error prone record in their analysis. Hence my criticism that this analysis is too narrow. Santer certainly got one thing right: he didn’t shy away from comparing models to all of the available obs data (as far as I can see).
Ron, there is a deep, fundamental problem with your analogy. Your analogy and the graphic measure entirely different things. This mixup is likely in part due to the nickname of the red spot in the graphic, which is misleadingly called the “tropical hot spot”. It is not a hot spot at all.
Your analogy measures the temperatures above the man in the bed.
The graphic, on the other hand, does not show the temperatures. It shows the temperature trends, which is a very, very different thing.
I hate to say this, because your analogy is very tempting. But because they measure totally different things, your analogy falls apart completely. There actually is a so-called tropical “hot spot” in the real atmosphere … but it’s not a hot spot. It is a part of the atmosphere which both warms and cools more than the surface when the surface warms or cools. This is not a “hot spot”, and it has absolutely nothing to do with your analogy.
Please see my WUWT post on the subject.
All the best,
w.
The IPCC assumes that the ratio isnāt 1:1 even but entirely downwards, which is the first fundamental mistake.
Actually to a first approximation it is not bad.
Do a paper experiment. You have two mirrors back to back. Each reflects 50% of the incident light. The rest passes through the mirror. On the first pass through the system the first mirror reflects 50% of the light. The second mirror reflects 25% of the total light back to the first which passes 12.5% back to the origin.
So two 50% reflecting 50% transparent mirrors in series without going through all the backing and forthing (which will increase the reflection) reflects 62.5% of the incident light. You pile more mirrors in series and it gets better.
If you work it all out two 50% mirrors in series will reflect 75% of the incident light. Add more mirrors and it gets better and better.
Mirrors in some lasers work that way. So it may take 10 or 100 reflections for a photon to escape. If you assume the reflecting surface is at 50 Km and it takes 100 reflections. About 1/30th of a second. On average. Which gives you a ball park. Not counting any delays of reradiation by the absorber.
Hey Stevo:
Here is a temperature profile of the atmosphere.
http://apollo.lsc.vsc.edu/classes/met130/notes/chapter1/vert_temp_all.html
Convection produced clouds only go to the top of the troposphere. The temperature decreases steadily from the ground up to the tropopause. The temperature increases above that, but there is not much if any convection there that I can see any cause for at least.
So, wattsupwiththat? You hypothesis does not make sense.
Stephen Wilde (16:12:11) : Your: highly relevant article — Dated: July 16, 2008
I know you have been reading and thinking seriously about these issues for the past year. I wonder how you might reword parts of your article if you were writing it from scratch today, especially parts 5 and 6 (first 3 paragraphs)?
Well, let’s give Stevo some credit here. Frankly, it’s the first time I’ve seen an AGW argument with a plausible mechanism and some data to support it. If we check Roy Spencer’s UAH site, for example, the data do indeed show warming at lower altitudes and cooling at higher ones in a more or less secular trend for the last ten years. At 1 km, the temp anomaly is a solid 2 deg F compared to the 20 year average (interestingly, 8 of the last 12 years were around record highs). By 4.4 km, the anomaly is close to neutral, and it’s negative higher up.
So we have a hypothesis that we can test.
For example, if the temp anomaly then increases the closer to the surface, should the surface temp anomaly not be around 3 deg F?
The comment was:
—————-
M. Simon (04:21:27) :
There are two possibilities for where the āmissing heatā is being stored. In the land or in the ocean. The oceans are not heating. In fact they may be cooling.
That leaves the land. Is there any evidence of the land heating?
BTW the hot spot is necessary for radiation balance. The earth heats in conformance to the second law from a hot body ā the Sun ā to a cool body ā the Earth.
—————-
Dear Simon,
.
YOU are DREADFULLY incorrect in your presumption/assumption/assertion.
.
Energy cannot be =stored= in the same form in which it was received.
.
Since heat energy must change form to be stored then it NO LONGER has AFFECT as a source of ‘heat.’
.
Plants store energy by CONVERTING it to another form.
.
You talk about ‘missing heat.’ There is ‘no such thing.’
.
If solar energy is not absorbed and thence re-released upon absorption, then it is converted to something else and is NO LONGER a source of heat energy.
.
Finally, your last remark above is so laughable as to not deserve a reply. But I’ll provide you with one.
.
IF the Earth were to the be receiver of the Sun’s energy such as to absorb 100% of the impinging energy, then upon nightfall, the Earth would become a freezing ice box.
.
Honestly, where do you get such ideas?
There will never be a hot spot for the simple reason that we have such a thing as wind.
The atmosphere is essentially transparent.
Most of the heat is transferred from the earth to the atmosphere via conduction and convection. All materials radiate at all times proportionally to T**4. In the dense lower atmosphere convection and conduction dwarf radiation heat transfer. As the pressure gets lower and lower radiation assumes a larger role and the other modes diminish significantly.
I don’t know about your temperature profile. It looks pretty but of the high performance aircraft I have been in at 40 to 50 k ft, it is damn cold.
Highlander,
Evidently you are not familiar with textural conventions “missing heat” means supposed missing heat.
And who said anything about the same form?
And you know I was under the impression that you warm something up and it radiates heat in conformance with its temperature (T^4) and albedo. At least that was one of the (minor) factors in the design of low temp (below 100 C) coolers for semiconductors. But perhaps I got it wrong.
Heat is really devilish stuff and hard to think about. Convection, conduction, and radiation all come into play to varying degrees. And partial differentials. Lots of partial differentials.
In any case I was hoping to avoid a dissertation and get an answer to my question. Guess not.
true believer (16:46:22) : But….all things combined mean: Air no heat saving (Big chief says).
I’m still waiting for you guys to bring some light into the question of whether or not any GHG AGW is strictly additive to natural heating or if it is buried in natural heating. If you take a 30 dB sound and add another 30 dB sound to it, whether it is the same source or a different sound, same frequency or different frequency, you don’t get 60 dB.
It this the case for warming? If you have 2 degrees of natural warming, and then add .5 degrees of anthropogenic CO2 to that warming, do you get 2.5 degrees of warming? My hunch is this is not additive. Comments?
This site has quite a good explanation of what Stevo is saying:
Greenhouse effect
Stefan (09:02:35) :
The presence of CO2 is a signature of greed. Thatās the signature greenies are really thinking about. If we can tackle that mistaken perception, then we can all go home.
I don’t know of any immediate cure for envy. A deadly sin – according to some.
āā” Phil M (04:27:58) :
Let me take a simpler stab at an explanation…
Consider the imapct of CO2 alone. The earth absorbs energy from the Sun mostly in the visible part of the spectrum. Call this amount G. Earth’s temperature increases as a result. Anything with a temperature above 0 K emits power proportional to its absolute temperature to the fourth power. A steady earth “mean” temperature obtains when the emitted power (in the IR bands) equals the absorbed power from the Sun. In other words G is absorbed and G is radiated away. At present this “mean” temperature is about 288K or so.
Add CO2 or some other gas that absorbs heat radiation but is transparent to visible. Suppose the amount of heat radiation the CO2 absorbs is X. This absorption warms the gas until it also emits X, and the gas now reaches a steady temperature. The gas emits one-half of this X toward space and one-half toward earth. We can now look at the situation from two perspectives, either of which describes why the Earth becomes warmer.
1) The amount of downward power reaching the earth is now G+one-half X, which is larger than without CO2, so the earth must warm to emit the increased power and reach a new, slightly higher steady temperature.
2) With CO2 in place the absorbed solar power is still G, but the outgoing thermal power above the CO2 layer is G minus one-half of X. So there is an imbalance and the earth must increase its temperature to emit a little bit more power and achieve a balance again.
What Mr. House says here, in effect, is that all sorts of other processes go on beneath and within the CO2 “blanket” but the distribution of resulting temperature might provide a reasonable “fingerprint” of CO2 as a cause, yet no one can really be pinned down to say that “such and such” is a “fingerprint” of AGW and that it would provide a definitive test of the hypothesis.
Pamela Gray (19:25:47) :
Iām still waiting for you guys to bring some light into the question of whether or not any GHG AGW is strictly additive to natural heating or if it is buried in natural heating.
One of the reasons of using watts/m**2 is so that one is talking about heat inputted and outputted, and heat (energy) is additive. So if one uses this ( for me) bizarre energy system ( bizarre because the problem is three dimensional) the CO2 contribution will be additive to the natural contributions (including H2O).
Bob D (19:32:52) good explanation of GHGs
Bob, Thanks for this link.
You’re welcome, here’s another along the same lines, and dealing with the hotspot in particular:
What Greenhouse warming?
Ed Long (13:27:46) : “I am a skeptic of AGW and do have a large problem with the IPCCās work. So what I say here refers to the misuse of the two figures. I have seen these two figures so compared before. But, I am afraid the user overlooks the respective scales and thus makes too much regarding the differences. The modeled data is for a period of 41 years; the scale is C/41 years. The HadAT2 data is for C/decade, or C/10 years. Taking this into account then the hot spot in the modeled data reduces to a range of values from 0.25 C/10 years to 0.3 C/10 years. The HADAT2 data places the values from 0 C/10 years to .1 C/10 years. The ratio of these is ā3ā² for the upper end. So, even though there is a difference between modeled and observation we should be cautious in making too much out of this.”
It is indeed unfortunate that these diagrams are plotted to different scales, and that is well worth pointing out. However, if you look carefully at them, it is arguable that on the same scale, the difference would be even greater. There is a height about 4km above the equator that is actually cooling (blue) where the model wants a hotspot. And at all latitudes the actual data from about 15 km upwards is either cooling very much faster than the model, or cooling where the model is warming. The two are irreconcilable no matter the scale because they have fundamentally different shapes. Therefore we can make as much out of it as it warrants – it disproves the model.
You are right, decibels don’t add because it is a logarithmic scale. Doubling adds about 3 decibels. See http://www.phys.unsw.edu.au/jw/dB.html .
I think your question about warming is not well enough defined for a simple answer. Power radiated from a body is proportional to T to the 4th, so more power will radiate than the sum of the powers radiated by either process individually. You would have to have specific processes in mind to answer the question, I suspect.
In my opinion, the question is not “Is there an Anthropogenic or for that matter a Physiogenic (Natural) Greenhouse Effect?” Instead it is “Is the industrial age Anthropogenic Atmosphere Change appreciably modifying our global climate?”
The most telling argument as to why this may not be the case is that there may be a law of diminishing effect for increasing concentrations of greenhouse gasses. This is much like the transparency reduction observed with increasing coats of black paint on a window. The first coat does most of the work.
David Archibald has presented a chart that suggests our current carbon dioxide concentration may be equivalent to a second or third coat of paint.
With the sun now going through a record period of minimum activity, we should soon have evidence proving that we do or do not have a serious Anthropogenic Climate Change problem.
Nice article, Mr House. It is a clear enough analogy, despite the attempts of some people to confuse your methodological criticism of AGW theory (different types of atmospheric phenomena produce different signatures in the atmosphere, which is how you detect the difference between them) with a mechanical one (Fred’s blanket behaves like CO2 in the atmosphere). After all, analogies are there to highlight the point you are trying to make, not to reproduce the phenomenon you are studying; they are retorical tools, not scientific ones.
Ooops!
retorical > rhetorical
Speed and spelling do not mix; sorry.
I think I’ve got it!
If you put a blanket on a corpse it will NOT warm up. š
Pamela Gray (19:25:47) :
I like your analogy of DB and whether GHG AGW is additive. Having earnt my living as a musician, if you have 2 trombones it is louder than 1. However, if 1 trombone is really going for it there are a lot of instruments that no matter how loud they are in themselves you won’t hear them, and more importantly the Trombone won’t be any louder.
So I think that whether 2 different sources of heat are additive is conditional.
“That laughable statement tells me straight away that youāve never read any IPCC reports.”
Every time I’ve looked, the evidence that CO2 induced warming will be amplified by water vapor feedback has seemed to consist of models (generally computer simulations) which (1) assume a lot of feedback; and (2) fit some historical measurements.
Of course that’s not real evidence. But if you have some real evidence, I would be very interested to see it.
M. Simon (19:55:39) : I donāt know of any immediate cure for envy. A deadly sin ā according to some.
Aha, it hadn’t occurred to me some greenies could be motivated by plain envy, but it makes sense.
Glug,
I don’t know any more about McIntyres paper other than what I read on his website:
http://www.climateaudit.org/?cat=129
The Santer paper seems to be a rebuttal of Douglass et al who claimed model predictions diverged from observed data. Santer refer to this as the H2 hypothesis and claims that it does in fact conform to models because the observations lie within 2 sd of the observations. I do not find their findings convincing because all they are saying is effectively that model outputs are so varied that we can’t say they are inconsistent from observations. Yet their result rests right on the edge of 2 standard deviations. It seems to me that if you remove the outlier model and repeat the test then the observations would lie outside of the 2 standard deviations. McIntyre has also found that they terminated their observations in 1999 and if you use a more up to date dataset the H2 hypothesis is rejected.
Have you ever seen somebody lick the chutney spoon in an Indian Restaurant and put it back? This would never have happened under the Tories.
This info on the atmosphere is really good if you have not looked at the compostion, pressure profile and temperature profile of the atmosphere.
http://apollo.lsc.vsc.edu/classes/met130/notes/chapter1/history.html
**************************
Bob D (19:32:52) :
Jim (17:37:02) :Hey Stevo: ā¦Convection produced clouds only go to the top of the troposphere. The temperature decreases steadily from the ground up to the tropopause. The temperature increases above that, but there is not much if any convection there that I can see any cause for at least.
This site has quite a good explanation of what Stevo is saying:
Greenhouse effect
****************************
Ok, the explanation given at the link at least makes some sense. This ***stuff*** about pressure (as in compression) causing the heating at the surface seems like BS to me. If the Earth were without atmosphere and suddenly the atmosphere fell on to the Earth, the atmosphere would heat due to the compression. But then it would cool off. The pressure would go down somewhat as it cooled but obviously the pressure before vs. after the event would be greater than zero.
Can the process explained at the link be modeled easily, i.e. from first physical principles?
I just realized I responded to the wrong person on an earlier post (I’m still learning here folks so please bear with me).
John F. Hultquist (08:45:50) :
Let me take a repeated stab at an explanationā¦
Consider the impact of CO2 alone. The earth absorbs energy from the Sun mostly in the visible part of the spectrum. Call this amount G. Earthās temperature increases as a result. Anything with a temperature above 0 K emits power proportional to its absolute temperature to the fourth power. A steady earth āmeanā temperature obtains when the emitted power (in the IR bands) equals the absorbed power from the Sun. In other words G is absorbed and G is radiated away. At present this āmeanā temperature is about 288K or so.
Add CO2 or some other gas that absorbs heat radiation but is transparent to visible. Suppose the amount of heat radiation the CO2 absorbs is X. This absorption warms the gas until it also emits X, and the gas now reaches a steady temperature. The gas emits one-half of this X toward space and one-half toward earth. We can now look at the situation from two perspectives, either of which describes why the Earth becomes warmer.
1) The amount of downward power reaching the earth is now G+one-half X, which is larger than without CO2, so the earth must warm to emit the increased power and reach a new, slightly higher steady temperature.
2) With CO2 in place the absorbed solar power is still G, but the outgoing thermal power above the CO2 layer is G minus one-half of X. So there is an imbalance and the earth must increase its temperature to emit a little bit more power and achieve a balance again.
What Mr. House says here, in effect, is that all sorts of other processes go on beneath and within the CO2 āblanketā but the distribution of resulting temperature might provide a reasonable āfingerprintā of CO2 as a cause, yet no one can really be pinned down to say that āsuch and suchā is a āfingerprintā of AGW and that it would provide a definitive test of the hypothesis.
==================
There have been several postings on this thread that the maximum Delta T occurs in Mid troposphere because of water vapor feedback, and wouldoccur in the presense of any cause. It is therefore not a true “fingerprint”. If anyone is still out there, I have a question.
Is the warming an effect of latent heat, which ties it firmly to water vapor, or is it the result of the new radiation balance in the atmosphere, which means it must also occur with lesser amplitude with just CO2?
I suppose I can go make several runs of MODTRAN at UofChicago to answer this, but I’d like to hear what someone thinks, or what they have read.
Steve in SC (18:17:14) :
> The atmosphere is essentially transparent.
Not true, at least not true at some IR and UV wavelengths. (Why would we evolve sensitivity to wavelengths that don’t illuminate the ground?)
True if you’re talking about visible wavelengths, opaque if you’re talking about the wavelengths in the CO2 and H2O absorption bands. Overall, only 15-30% of upward going thermal radiation makes it out on the first try.
See http://www.globalwarmingart.com/wiki/Image:Atmospheric_Transmission_png hanging off of my http://wermenh.com/climate/science.html
The whole mechanism of the greenhouse effect depends on the atmosphere _not_ being transparent!
Jim (05:17:42) : Can the process explained at the link be modeled easily, i.e. from first physical principles? I’ll take a stab at it, I may not have the semantics you want though. I think of it this way, all molecules above absolute zero have motion, or a mean free path if you will, that describes the space between the molecules. If you shrink this space (compression), the molecules collide more, creating friction and more heat.
The chinook winds show this, with a high pressure system west of the rockies and a low on the east side, the air is sucked over the mountains toward the low. The air is compressed as it descends the eastern slope and warms 4-5Ā°F per 1000′ of descent.
Kevin Kilty (06:23:09) :
Is the warming an effect of latent heat, which ties it firmly to water vapor, or is it the result of the new radiation balance in the atmosphere, which means it must also occur with lesser amplitude with just CO2?
I suppose I can go make several runs of MODTRAN at UofChicago to answer this, but Iād like to hear what someone thinks, or what they have read.
Try realclimate.com
There was a spate of calculations that the hot spot should appear for any strong warming,
Apologies for length/multiplicity. It seems I have several comments to answer.
Jim,
“OK, Iāll bite. So you add 200 ppm to the atmosphere. The average emission altitude goes up. So what?”
The air at the average emission altitude settles at -24 C, to balance the heat coming from the sun. Above or below that altitude, the temperature changes at a constant rate. The further away from the average emission altitude you are, the warmer or cooler it is. So if the emission altitude moves further away from the surface, the surface will get warmer.
Doubling CO2 raises the emission altitude by about 160 m which changes the temperature at the surface by about 1 C. Changing CO2 by 40% changes temperature by about half that – ignoring all feedbacks and approximations.
“The extra 200 ppm of CO2 wonāt add any significant pressure due to the extra gas.”
Correct.
It’s not CO2 that changes the pressure, it’s the altitude. The higher you go, the thinner the air is.
“If you are saying the extra CO2 will heat the air and thereby increase the pressure, OK.”
No, I’m not.
“Why doesnāt the convection upwards take away as much heat as was deposited by the sinking gas?”
It takes away more. But you have to be careful here because in thermodynamics ‘heat’ is not the same thing as ‘temperature’. In fact, the changes in temperature I’m talking about take place without adding or removing any heat – that’s what the word “adiabatic” means. The temperature changes because the compression does “work” on the gas. But I need to be very careful here because these words have technical meanings in thermodynamics that don’t exactly match their everyday meanings.
The air at the surface absorbs heat from it. It rises upwards, changing temperature but not exchanging any heat. And then it radiates the heat to outer space, cooling it even further.
“So just what is it about CO2; and how about CH4, that is assymmetrical. Explain how this assymetry is any different from the assymetry of O2 and N2.”
Sorry. I was trying to keep it simple.
Molecules can contain thermal energy in a number of ways. Translation, rotation, stretching/contracting, bending, or by different parts of the molecule rotating with respect to other parts. Each sort of motion has a set of characteristic frequencies, and all the motions contribute to its absorption/emission spectrum.
If you take an N2 molecule, it can translate, stretch, or rotate about two axes. But rotating about the long axis doesn’t change anything, and you can’t bend it.
CO2 has three atoms in a straight chain, which can also bend. The carbon atom can be off-centre from the straight line between the oxygen atoms. And the two bonds can stretch independently.
H2O has three atoms in a bent chain, which means that rotating it about the third axis is also meaningful.
A molecule interacts with an electromagnetic wave via the charge distribution around it. For example, in H2O the oxygen has a negative charge compared to the hydrogens, so an electric field will pull the oxygen one way while pushing the hydrogens the other. Similarly, in CO2 the oxygens tend to be more negative than the carbon. Essentially, the asymmetry in this case is that the molecule contains atoms of different elements instead of all the same element. Figuring out exactly what sort of motion corresponds to what absorption line is a bit technical. But as a general rule, the more “messy” – big, complicated, asymmetrical – a molecule is, the more ways it can move and therefore the more likely it is to absorb/emit. There are greater and lesser degrees of symmetry.
jim,
“Stevo ā what you have said is interesting. If you would suffer one more questsion. I thought sunlight mostly passed through the atmosphere and was absorbed by the surface of the Earth, including the oceans ā even there it eventually goes dark at some depth.”
Correct. It does.
“So the sunlight is absorbed and heats the Earth. I thought that is why the surface of the Earth is hot.”
The heat comes in, and almost exactly the same amount of heat goes out. Think of a river, flowing down into a lake behind a dam, and then over the spillway of the dam to continue down to the sea. The amount of water entering the lake is the same as the amount leaving it. If river flow in increased, the spillway flow out would increase too. The height of the lake surface depends on the height of the dam.
It’s actually a bit more complicated than that. I’m going to try to extend the analogy a bit, but if this doesn’t work for you, ignore it and stick with the basic dam.
Imagine that the river flowing in spins the lake water around in a whirlpool, so the water level is lower in the centre than at the edge. The outlet pipe sticks up into the lake about halfway between centre and edge. The water flows out of the lake through the pipe when the water at that point is higher than its top.
You are sat at the edge of the lake, and the water where you are is a lot higher than the top of the pipe, because of the whirlpool effect. But it’s stable, because if more water comes in, more will flow out through the pipe.
But now imagine that without changing its height, somebody moves the pipe nearer the centre of the lake. The whirling water is lower here, so it will stop flowing out until it has topped up a little. This will raise the water level throughout the lake, including at the edge where you are.
The whirl of the water acts like pressure, the variation in lake height is like the greenhouse effect, the pipe is like radiation of heat to space, the outside of the lake is the ground, and the centre is the top of the troposphere, and moving the pipe is like adding greenhouse gases.
“Again, why do you say it is pressure?
Pressure is the reason the surface is warmer than -24 C, which is the average temperature it would be if we had the same sun, but no atmosphere. It’s the average temperature on the moon, for example.
jim,
“Convection produced clouds only go to the top of the troposphere. The temperature decreases steadily from the ground up to the tropopause. The temperature increases above that, but there is not much if any convection there that I can see any cause for at least.”
Quite correct. The temperature rises partly because of the absorption of ultraviolet radiation by ozone, and partly because the outward heat flow is no longer strong enough to drive convection, so the old principle of hot air rising to the top applies.
Virtually all the heat emitted from the Earth (and hence all greenhouse effect physics) comes from the lowest layers. The upper layers don’t take much part because, while hotter, they’re much less dense. It’s essentially a hot vacuum, by human standards.
—-
Steven,
“Well, letās give Stevo some credit here. Frankly, itās the first time Iāve seen an AGW argument with a plausible mechanism and some data to support it.”
I think at this point I should firmly state that I’m a sceptic on catastrophic AGW. That CO2 will in principle raise temperatures is not really controversial – the question is whether it is significant compared to all the other natural drivers, whether it is the explanation of the observed warming, and whether feedbacks and delays mean it could be catastrophic. I disagree with the IPCC on all of that.
All I’m trying to do here is to correctly state the theory the IPCC et al are actually proposing – something they themselves are shockingly bad at. It’s possibly because doing so means changing their story, and opens up a whole new set of attacks, like is the adiabatic lapse rate really a constant? (The answer being: of course not.)
All the further questions about feedbacks and hotspots are still valid.
—-
Bob,
“This site has quite a good explanation of what Stevo is saying:
Greenhouse effect”
I only glanced at it, but I can tell you that their section on the “runaway greenhouse” is wrong. There’s no such thing. The surface of Venus is hot because it’s got high level opaque clouds, and an atmospheric pressure more than 90 times that on Earth. See my “fictional planet” above.
Incidentally, because the clouds on Venus reflect more light back, the total heat input from the sun is less there than it is on Earth, despite being closer in.
I think they get quite a lot of the rest of the explanation wrong, too. But a few bits are right. š
>> Kevin Kilty (06:23:09) :
. . .
There have been several postings on this thread that the maximum Delta T occurs in Mid troposphere because of water vapor feedback, and wouldoccur in the presense of any cause. It is therefore not a true āfingerprintā. If anyone is still out there, I have a question.
Is the warming an effect of latent heat, which ties it firmly to water vapor, or is it the result of the new radiation balance in the atmosphere, which means it must also occur with lesser amplitude with just CO2?
I suppose I can go make several runs of MODTRAN at UofChicago to answer this, but Iād like to hear what someone thinks, or what they have read. <<
I like Kiehl and Trenberth (Earthās Annual Global Mean Energy Budget) 1997, not because the numbers are particularly accurate, but because it represents the quintessential model of the Earthās average energy flows. So according to Kiehl et al., the atmosphere receives 67 W/m^2 directly from the Sun, 24 W/m^2 from sensible heat flux, 78 W/m^2 from latent heat flux, and 350 W/m^2 from the surface. (The surface radiates 390 W/m^2 which is what a blackbody radiates at a temperature of 288K, and the other 40 W/m^2 escapes through the IR window.) This adds up to 519 W/m^2 that the atmosphere absorbs on average. The atmosphere doesnāt radiate one-half to space and one-half towards the surface. Itās more like two-fifths (195 W/m^2) upward to three-fifths (324 W/m^2) downward.
The latent and sensible heat fluxes are also called the Earthās air conditioners, because they cool the surface and dump the energy directly into the atmosphere (increasing its temperature in the process).
Adding GHGs to the atmosphere primarily affects the IR window and may affect the upward-downward radiating ratio. Narrowing the IR window causes the surface temperature to rise, but the atmosphereās temperature must rise faster (the hotspot). This is just the required response of the physical setup. For a surface temperature increase of x, the atmosphereās temperature must increase at a minimum of 1.39x. If we apply the bulk aerodynamic formula to the sensible heat flux (as Kiehl et al. do) and increase the latent heat flux by the same percentage increase as the surface temperature, then the atmosphereās temperature must increase by more than 1.60x.
By narrowing the IR window, I avoid all the arguments as to which GHG is doing the absorbing. Any GHG will narrow the IR window.
What this model is saying is that the current surface warming canāt be due to GHGs.
Jim
>> Ric Werme (06:54:24) :
Overall, only 15-30% of upward going thermal radiation makes it out on the first try. <<
According to Kiehl and Trenberth (1997), itās more like 10% (40/390); however their calculation is badly flawed. Correcting their error, I get an IR window of about 22% (87/390). I can only find references to Kiehl et al. The default value for the IR window appears to be 40 W/m^2. Do you have another source for this value? I doubt that 40 W/m^2 is valid.
Jim
anna v (10:55:03) :
Kevin Kilty (06:23:09) :
Is the warming an effect of latent heat, which ties it firmly to water vapor, or is it the result of the new radiation balance in the atmosphere, which means it must also occur with lesser amplitude with just CO2?
I suppose I can go make several runs of MODTRAN at UofChicago to answer this, but Iād like to hear what someone thinks, or what they have read.
Try realclimate.com
Thanks, OK, I did, and as someone else on this thread said the issue is a change to the wet pseudo-adiabat. It thus involves additional water vapor which means that anything that causes the climate to warm, will, eventually, produce this signature, because water vapor (in the absolute measure) will increase. So, if we were to not observe this signature it would indicate that no real warming had occurred–for example, if the observed warming were the result of instrumentation errors.
Good analogy.
Here’s a question for you though regarding pressure (I’ve thought about this for a while and it confuses me) – If there was an atmosphere but no GHGs, wouldn’t the average emission level be at the surface, since nothing is preventing the emission of IR to space from the surface? Wouldn’t that then imply a surface temp of about 255K (ie: Ts=Te assuming e=0 by Stefan-Boltzmann), to ensure radiative balance? And wouldn’t that then determine the pressure (and volume) by PV=nR(255) because the atmosphere is free to expand or contract, in principle?
Maybe I’m missing something here. I’m aware the pressure (density) is partly determined (imposed) by gravity, so presumably the surface equilibrium temperature would end up higher than 255K, but then what about the radiative balance?
*****************************
Stevo (12:00:37) :
But you have to be careful here because in thermodynamics āheatā is not the same thing as ātemperatureā. In fact, the changes in temperature Iām talking about take place without adding or removing any heat ā thatās what the word āadiabaticā means. The temperature changes because the compression does āworkā on the gas. But I need to be very careful here because these words have technical meanings in thermodynamics that donāt exactly match their everyday meanings.
***********************
Thanks, Stevo. I have had thermodynamics and do understand the meaning of adiabatic and heat vs. temperature. I still don’t get the pressure thing you talk about. I can see where adding some CO2 would raise the “zero point” where radiation in = radiation out (at least I think that is what you mean.) But I don’t see how that raises pressure. And even if you add 200 ppm CO2 suddenly and the atmosphere somehow compressed, the heat would eventually dissipate, the temperature and pressure would drop, then things would be in equilibrium again. That is, there would be no continuous compression – it would be a one off event.
It seems to me that once you have added enough carbon dioxide to make the atmosphere totally opaque in specific frequency ranges, you cannot make it more opaque in those bands by adding more CO2. All we can do is increase the thickness of the opaque zone.
According to the table presented by David Archibald, we have gotten almost all of the opacity from carbon dioxide that we will ever get. Even pure carbon dioxide gas is perfectly transparent to visible light.
There is a possibility that modern industrial activity is now adding other gasses that are extending the band of opacity. But so far, all the focus has been on controlling carbon dioxide.
BTW, William F. Ruddiman has presented a theory that greenhouse gasses generated at the onset of human farming, 8000 years ago, may have prevented a next scheduled ice age. Scientific American, March 2005.
P Wilson (14:19:07) :
“Stevo: I just had an email from the Met Office here in the UK in response to a question as to why temperatures plummeted during the solar eclipse. They categorically replied that āC02 doesnāt retain heat. It intercepts and transfers heat to the atmosphereā Therefore, despite C02 being the great climate driver, it tells the heat to go elsewhere, since C02 doesnāt seem to like absorbing heat.”
Is the Met Office suggesting that CO2 captures radiation from the sun (that has reached us through a vacuum and then passes that heat into the Nitrogen, Oxygen, water vapour and trace gases, so that the atmosphere warms? That flies in the face of the research of Count Rumford, a founder member of the Royal Institution, who designed efficient open fireplaces towards the end of the 18th century.
http://www.rumford.com/Rumford.html
Heat is transferred by conduction, convection and radiation. Rumford applied his knowledge of heat to the improvement of open fireplaces, so that fully 50% of the potential heat stored in timber was radiated out into the room. This radiation does NOT heat the air in the room, but warms solid items such as walls ceiling and floor, furniture and humans. Warmth imparted to the air happens by convection from warmed surfaces and these warmed surfaces such as a chair can also warm us by conduction, when we sit on it. That how bonfires warm us.
Infra red heating lamps do not heat the intervening airspace either, but you feel the heat on your body. Propane fired heaters radiate both visible light and infra red. Sunlight falling on solids and liquids warms them by radiation, with conduction transferring the heat in metals and convection in liquids. Theoretically, Mercury has both methods of heat transfer available to it.
This property of CO2 to capture radiated heat from the sun without itself heating up is astounding. By what mechanism is CO2 able to extract heat from sunlight passing through it, (a property that is not available to any other gas AFAIK). Then the CO2 gives this warmth to the other gases of the atmosphere!!!
I think we should rename this mighty overblown weather balloon of an organisation as the Meterological Office of Conitive Dissonance.
*********************
Bob D (17:06:35) :
Stevo (12:10:18) : The whirl of the water acts like pressure, the variation in lake height is like the greenhouse effect, the pipe is like radiation of heat to space, the outside of the lake is the ground, and the centre is the top of the troposphere, and moving the pipe is like adding greenhouse gases.
*************************
Actually, the analogy does not look so good to me, at least. When you move the pipe up in the dammed lake, you actually add mass to the vertical dimension. This accounts for the increase in pressure in the lake when the level gets higher. But moving the dynamic radiative equilibrium point higher in the atmosphere adds no mass. If you look at the ideal gas law, PV = nRT, an increase in temperature will result in an increase in the product of pressure and temperature. While the atmosphere is held down by gravity, it is not the same as being confined in a gas cylinder for example. So if T increases, V can increase and satisfy the ideal gas law. So you have not demonstrated that an increase in height of the radiative equilibrium point will increase pressure.
I found it! The missing red spot! Its on my nose from yesterday’s Sun! We can all rest now. CO2 has been proven.
**********
If you look at the ideal gas law, PV = nRT, an increase in temperature will result in an increase in the product of pressure and temperature.
**************
That should read “in an increase in the product of pressure and volume”
Bob D,
“Hereās a question for you though regarding pressure (Iāve thought about this for a while and it confuses me) ā If there was an atmosphere but no GHGs, wouldnāt the average emission level be at the surface, since nothing is preventing the emission of IR to space from the surface? Wouldnāt that then imply a surface temp of about 255K (ie: Ts=Te assuming e=0 by Stefan-Boltzmann), to ensure radiative balance?”
Yes.
“And wouldnāt that then determine the pressure (and volume) by PV=nR(255) because the atmosphere is free to expand or contract, in principle?”
No. That formula is valid for a volume of gas all at the same uniform temperature and pressure. We would still get pressure dropping with altitude. And if there was convection, you could still get the temperature of the air above the surface falling even further below the Stefan-Boltzman temperature, while the surface remained at that temperature.
As I said above, it’s how the top of the troposphere is cooled to -54 C.
jim,
“I can see where adding some CO2 would raise the āzero pointā where radiation in = radiation out (at least I think that is what you mean.) But I donāt see how that raises pressure.”
It doesn’t raise the pressure. It moves the “zero point” to a different place, where the pressure is different.
It’s the pressure difference between surface and average emission altitude that controls the temperature difference between surface and the “zero point”.
“When you move the pipe up in the dammed lake, you actually add mass to the vertical dimension. This accounts for the increase in pressure in the lake when the level gets higher.”
The height of the water, equivalent to mass, is analogous to heat, not pressure. It’s an analogy, not an identical piece of physics, and water pressure does not correspond to atmospheric pressure. Moving the pipe is analogous to increasing the total heat in the atmosphere.
*********************
Stevo (10:46:40) :
It doesnāt raise the pressure. It moves the āzero pointā to a different place, where the pressure is different.
Itās the pressure difference between surface and average emission altitude that controls the temperature difference between surface and the āzero pointā.
*************************
So, are you making the “environmental lapse rate” argument?
Jim,
I suppose you could call it that. I just think of it as “the greenhouse effect”.
No, I get that, I think we’re in agreement. I suppose I was confused by your statement above: “Pressure is the reason the surface is warmer than -24 C, which is the average temperature it would be if we had the same sun, but no atmosphere.”
It seemed you were saying that the atmosphere’s pressure alone would raise the temperature above the S-B temperature, and I couldn’t see how it would do that. Under the scenario you mentioned, the maximum temperature would still be at the surface, and would be 255K. In other words, we would have an atmosphere, but it would start at 255K at the surface and decrease vertically from there.
The way I read your comment, I thought you were sort of implying that if there were no GHGs we would still have temperatures higher than S-B simply due to pressure. I’ve seen this argument advanced before you see, and it’s never made sense to me.
I think I’ve misinterpreted your statement, and you meant “Pressure in the presence of GHGs is the reason…”
**************
Jim,
I suppose you could call it that. I just think of it as āthe greenhouse effectā.
****************
No problem. I have never thought nor said that CO2 doesn’t raise the temperature a bit. I just am not convinced that it will lead to any kind of catastrophic warming. I’m certainly not convinced it will raise the global average over about 1.5 degrees per century. And even if it did raise temps 3-5 degrees per century, I would probably be for just letting society adjust as necessary with no restrictions on burning oil and coal. However, I would be for a Moon-shot effort to build all the nuclear power stations we could and to put in place the nuclear infrastructure that would entail, to include the completion of Yucca mountain. Cheap power can make many things possible. I don’t have a problem with solar and wind energy either as long as they can compete with oil, coal, and nuclear without subsidies. (And yes, I would be for the government subsidizing the insurance for nuke plants – a lot of people wouldn’t accept them without it and the odds of ever needing it are slim to none.)
“”” Spector (20:08:18) :
>>>
BTW, William F. Ruddiman has presented a theory that greenhouse gasses generated at the onset of human farming, 8000 years ago, may have prevented a next scheduled ice age. Scientific American, March 2005. “””
I believe that in the very same article, Ruddiman presents the results of two ice cores which during the last 1000 years or so, had records going in exactly the opposite direction at the same time. It was either the CO2 or the temperature; but the two cores said the exact opposite was happening.
So much for ice core proxies. (and results inferred from them)
“”” Jim Masterson (12:34:46) :
>> Kevin Kilty (06:23:09) :
. . .
I like Kiehl and Trenberth (Earthās Annual Global Mean Energy Budget) 1997, not because the numbers are particularly accurate, but because it represents the quintessential model of the Earthās average energy flows. So according to Kiehl et al., the atmosphere receives 67 W/m^2 directly from the Sun, 24 W/m^2 from sensible heat flux, 78 W/m^2 from latent heat flux, and 350 W/m^2 from the surface. (The surface radiates 390 W/m^2 which is what a blackbody radiates at a temperature of 288K, and the other 40 W/m^2 escapes through the IR window.) This adds up to 519 W/m^2 that the atmosphere absorbs on average. The atmosphere doesnāt radiate one-half to space and one-half towards the surface. Itās more like two-fifths (195 W/m^2) upward to three-fifths (324 W/m^2) downward. “””
Jim, I’m interested in your last assertion that the atmosphere radiates 40% upwards, and 60% downwards. That seems counter-intuitive to me. The emission of a photon from the atmosphere would seem to be required to be isotropic; unless somehow these molecules can sense gravity.
That would argue for the probabilities being equal for each direction. Then when you look at the temperature and density gradients in the atmosphere, and the resultant CO2 spectrum broadening; that would seem to favor the upward path rather than the downward path; since the downward path to increased air density and temperature, and CO2 concentration, would imply ever more frequent re-absorptions followed by presumably isitropic emission splits between the up/down directions.
Are your numbers the result of measurements or modelling ?
George
“”” Stevo (12:02:17) :
āSo just what is it about CO2; and how about CH4, that is assymmetrical. Explain how this assymetry is any different from the assymetry of O2 and N2.ā
Sorry. I was trying to keep it simple.
Molecules can contain thermal energy in a number of ways. Translation, rotation, stretching/contracting, bending, or by different parts of the molecule rotating with respect to other parts. Each sort of motion has a set of characteristic frequencies, and all the motions contribute to its absorption/emission spectrum.
If you take an N2 molecule, it can translate, stretch, or rotate about two axes. But rotating about the long axis doesnāt change anything, and you canāt bend it.
CO2 has three atoms in a straight chain, which can also bend. The carbon atom can be off-centre from the straight line between the oxygen atoms. And the two bonds can stretch independently.
H2O has three atoms in a bent chain, which means that rotating it about the third axis is also meaningful.
A molecule interacts with an electromagnetic wave via the charge distribution around it. For example, in H2O the oxygen has a negative charge compared to the hydrogens, so an electric field will pull the oxygen one way while pushing the hydrogens the other. Similarly, in CO2 the oxygens tend to be more negative than the carbon. Essentially, the asymmetry in this case is that the molecule contains atoms of different elements instead of all the same element. Figuring out exactly what sort of motion corresponds to what absorption line is a bit technical. But as a general rule, the more āmessyā ā big, complicated, asymmetrical ā a molecule is, the more ways it can move and therefore the more likely it is to absorb/emit. There are greater and lesser degrees of symmetry. “””
Well Stevo you’ve just explained how the resonance absorption lines/bands of molecules come about, in particular with H2O and CO2, and I’m very familiar with that. But that energy is typically not re-emitted at the same photon freuency because the lifetimes of those excited states exceeds the mean time between collisions with the ordinary atmospheric gases; name ly N2, O2 and Ar. So the long wave Ir radiation absorbed by GHG molecules such as CO2 is rapidly transferred to the ordinary atmospheric gases as thermal energy, thereby raising the atmospheric temperature.
The question that I raised was by what rule are those ordinary atmospheric molecules/atoms prohibited from radiation due to their non-zero Kelvin temperature.
Because of the thermal agitation of those molecules, whehter in the earth’s atmosphere or the sun’s they must radiate since they contain accelerated electric charges due to the thermal vibration. If the solar atmosphere can radiate essentially black body thermal radiation , so can the earth’s atmosphere, so the radiation from the atmosphere is a function of the temperature of the ordinary gases of the atmosphere and is unrelated in any way to the nature or species of the GHG molecule, that capture the energy to warm the atmosphere.
It’s myth that gases do not emit black body (like) radiation and only solids do.
George
>> George E. Smith (17:24:41) :
Jim, Iām interested in your last assertion that the atmosphere radiates 40% upwards, and 60% downwards. That seems counter-intuitive to me. The emission of a photon from the atmosphere would seem to be required to be isotropic; unless somehow these molecules can sense gravity. <<
We know that photons can sense gravity (thanks to General Relativity and the equivalence principle), but the Earth doesnāt have enough mass to make this property of photons important. We also know that the density of the atmosphere changes with altitude. There should be more absorbers/emitters closer to the surface. So, yes, these molecules can sense gravity.
>> That would argue for the probabilities being equal for each direction. Then when you look at the temperature and density gradients in the atmosphere, and the resultant CO2 spectrum broadening; that would seem to favor the upward path rather than the downward path; since the downward path to increased air density and temperature, and CO2 concentration, would imply ever more frequent re-absorptions followed by presumably isitropic emission splits between the up/down directions. <<
Iāve tried modeling this for multiple layers, and it isnāt isotropic. You get more radiation going downward than upward. Itās another property of the model.
>> Are your numbers the result of measurements or modelling ? <<
They arenāt MY numbers, but Kiehl and Trenberthās numbers. The answer is both. If you read their 1997 paper, the top-of-atmosphere (TOA) outgoing value as measured by the satellite observations from Nimbus-7 and the Earth Radiation Budget Experiment (ERBE) is 235 W/m^2. If 40 W/m^2 comes directly from the surface, then that leaves 235 W/m^2 ā 40 W/m^2 = 195 W/m^2 for the atmosphere. The other 519 W/m^2 ā 195 W/m^2 = 324 W/m^2 must be going somewhere else (downās a good direction).
These numbers change slightly with their new 2009 paper, but the general relationships remain about the same. (I still donāt know where they get the 40 W/m^2 value for the IR window. The 1997 paper calculates it wrong, and the 2009 paper gets it from the 1997 paper.)
Jim
ok well perhaps another analogy with c02 and its absorbtion bandwidth (12-18 microns) is sunblock. If you go to the Sahara with factor 5, then even putting the entire tube won’t stop the more harmful solar exposure. Yet put even a small amount of factor 60 and you’re better protected than any amount of facto 5. I’d estimate that c02 has a weak factor 5 in climate factoring. No matter how much more is added, no increase in effect is discernible
**************************
Jim Masterson (00:46:03) :
Iāve tried modeling this for multiple layers, and it isnāt isotropic. You get more radiation going downward than upward. Itās another property of the model.
>> Are your numbers the result of measurements or modelling ? <<
They arenāt MY numbers, but Kiehl and Trenberthās numbers. The answer is both. If you read their 1997 paper, the top-of-atmosphere (TOA) outgoing value as measured by the satellite observations from Nimbus-7 and the Earth Radiation Budget Experiment (ERBE) is 235 W/m^2. If 40 W/m^2 comes directly from the surface, then that leaves 235 W/m^2 ā 40 W/m^2 = 195 W/m^2 for the atmosphere. The other 519 W/m^2 ā 195 W/m^2 = 324 W/m^2 must be going somewhere else (downās a good direction).
***************************
This is one of those ideas that does not pass the smell test. Either there is an inadequate understanding of what is happening or it's just wrong. It's kind of hard to "see" what's happening from the written description. Is there a chart that depicts their numbers somewhere? Also, if it is modeled, what mechanism does the model delineate to explain this counter-intuitive behavior? The obvious problem here is that the molecules will radiate in random directions. Also from morphological considerations, due to the curvature of the Earth and subsequently the atmosphere, actually there is a higher probability that a given photon will be radiated into space rather than hit the Earth. So, what is the mechanism responsible for this alleged behavior?
>> Jim (06:49:18) :
This is one of those ideas that does not pass the smell test. Either there is an inadequate understanding of what is happening or it’s just wrong. It’s kind of hard to “see” what’s happening from the written description. Is there a chart that depicts their numbers somewhere? Also, if it is modeled, what mechanism does the model delineate to explain this counter-intuitive behavior? The obvious problem here is that the molecules will radiate in random directions. Also from morphological considerations, due to the curvature of the Earth and subsequently the atmosphere, actually there is a higher probability that a given photon will be radiated into space rather than hit the Earth. So, what is the mechanism responsible for this alleged behavior? <<
The paper is online. Read it yourself (see figure 7). By all means donāt believe me. Model it yourself. Lots of things in physics are counter-intuitive.
Jim
Jim Masterson (07:21:35) : Thanks for the paper. I don’t have time to read it today, but I will get to it next week. It looks interesting.
***************
Jim Masterson (00:46:03) :
Iāve tried modeling this for multiple layers, and it isnāt isotropic. You get more radiation going downward than upward. Itās another property of the model.
*****************
OK, naive question here. I have an AMD Phenom 9850 Quad-core processor with 3.6 gig of RAM and 400 Gig hard drive.
1. Would your model run on my box?
2. Are you willing to share it?
George E. Smith,
“So the long wave Ir radiation absorbed by GHG molecules such as CO2 is rapidly transferred to the ordinary atmospheric gases as thermal energy, thereby raising the atmospheric temperature.”
The absorption of IR by greenhouse gases is irrelevant to the greenhouse effect. The only radiative physics that really matters with regard to GHGs is the final emission of IR to outer space.
You could think of it this way, if you like. The sun warms the surface, which warms the N2 and O2 touching it, which rises by convection to a high altitude, which transfers the energy by collision to H2O, which radiates to space.
The H2O radiating to space must do so at -24 C on average which is the amount required by Stefan-Boltzmann for heat balance, the N2/O2 at altitude is in thermal contact with it so must come to equilibrium at the same temperature, and once it’s done cooling and starts to descend to the ground again as part of the convective cycle, it’s temperature rises above -24 C as it gets compressed at lower altitudes. The temperature at the surface will therefore be considerably higher than -24 C, but not because of GHG absorption of IR.
“The question that I raised was by what rule are those ordinary atmospheric molecules/atoms prohibited from radiation due to their non-zero Kelvin temperature.”
Since I thought I already explained that, I suspect you probably don’t mean what I think you mean. Can you clarify or expand on why you’re asking?
“they must radiate since they contain accelerated electric charges due to the thermal vibration.”
Not necessarily. With a rotating N2 or O2 molecule, the acceleration on one end is equal in magnitude and opposite in direction to the acceleration on the other, so the waves they would emit will cancel.
“and is unrelated in any way to the nature or species of the GHG molecule, that capture the energy to warm the atmosphere.”
The atmosphere is not warm because GHGs capture the energy. This is the “trapped radiation” argument that I explained right at the start was wrong. Heat flows through the atmosphere by all sorts of mechanisms, including radiation, but the physics that decides what temperature it will be is just the bit I said. Convection combined with the change of pressure with altitude requires the temperature profile be a straight line with a given gradient, and the average altitude of emission to space fixes the straight-line intercept, because the temperature at the average emission altitude must be the Stefan-Boltzmann heat-balance temperature. The other heat flows will increase or decrease to push things back towards this state of affairs.
“Itās myth that gases do not emit black body (like) radiation and only solids do.”
Solids don’t emit perfect black body radiation, either. If solids don’t have energy levels in the right places, they’re completely transparent too. Take a close look at a Sodium Chloride crystal. The only difference between solids and gases in this regard is density.
I’ve heard this claim before as well about the “hidden heat”. A high school science student should be able to point out that this violates the law of conservation of energy. It does not simply “disappear” from detection. If the energy goes into some vessel, it should be possible to detect a heat anomaly from that vessel, because heat does not just stay somewhere. An energy system constantly seeks equilibrium and so heat travels to cooler areas. This movement can be detected by looking for a temperature anomaly from a heat sink.
Further, “temperature” (heat energy actually, of course) cannot “flow” from a cold source to a hot source.
Therefore, the AGW extremists’ mysterious pipeline” must (eventually) be hotter than what it will end up transferring heat to. So, if the “globe” is sucking in all of today’s heat energy, plus all the heat energy from 1998 through 2008, but world air temperatures have been decreasing over this same frame, where is the heat going? Hot air could heat up colder ocean waters anywhere they touch, but then how would the still-colder-on-average ocean waters begin heating up the average air masses above them? Why did ocean waters begin assuming this heat energy beginning in 1998 – but stop doing that absorption in 2025?
If the heat is going into the “oceans” (claiming the very true 1000x larger heat capacity of water compared to air), then how will the water suddenly and mysteriously change properties/methods/behaivor and suddenly begin heating up the air after 2025? There will not be enough of a temperature difference to move thirty years accumulated heat energy from the water “up” to the (suddenly assumed much colder for some reason?) air.
If the AGW extremists are going to claim that there is a thirty year “cycle” when the two masses (oceans and air) trade heat flow directions, where are the measured differences in the past thirty year cycles since 1890?
>> Jim (10:30:08) :
***************
Jim Masterson (00:46:03) :
Iāve tried modeling this for multiple layers, and it isnāt isotropic. You get more radiation going downward than upward. Itās another property of the model.
*****************
OK, naive question here. I have an AMD Phenom 9850 Quad-core processor with 3.6 gig of RAM and 400 Gig hard drive.
1. Would your model run on my box?
2. Are you willing to share it? <<
I have put the Kiehl-Trenberth model in an Excel spreadsheet (itās that simple). Does your computer run MS Excel? I have no problem with sharing the spreadsheet model.
The atmosphere-layer model is mathematical. It runs on a piece of paper. Iāve generated similar atmosphere-layer models (which is why I know these models do not radiate 50-50 upward-downward). The layer model doesnāt match Kiehl and Trenberthās numbers, so I donāt include it in the spreadsheet.
Jim
Just for reference: Black-body radiation is only emitted by black or partially black bodies. Transparent layers in the atmosphere only transmit or pass black-body radiation, whether that comes from the sun at 5780 deg K or is retransmitted by the earth at 300 deg K.
I believe that each “greenhouse” gas blocks transmission by converting the photons to heat (as phonons). This occurs at specific frequencies, determined by the molecular of structure and vibration modes of each gas. Generally, these absorption frequencies are in the infra-red range. I believe the heat generated by this process is primarily conducted to the surrounding atmosphere.
The “greenhouse” effect is caused by the fact that a higher temperature is required to force the same amount of energy through the remaining open bands. The sun is so hot that most solar energy arrives in the visible or optical frequency range where the atmosphere is transparent.
Please note that these comments do not apply to dust particles or clouds in the atmosphere. Carbon dioxide, the most notorious āgreenhouseā gas, is optically transparent.
Dear bloggers,
For what it’s worth, my simplistic understanding as follows:
Ignoring reflective clouds, the atmosphere is essentially transparent to the high frequency, incoming radiation from the Sun and the Sun’s radiation is overwhelmingly the only significant source of energy to the Earth. The land and the oceans absorb this radiation and are warmed. However, the land and the oceans also absorb and emit low frequency radiation (IR) and only that portion of the emitted radiation that escapes directly to space can cool the Earth. Some of the Land and oceans’ emitted radiation is absorbed by the atmosphere. The atmosphere also emits radiation and similarly only that portion that escapes directly to space can cool the Earth.
The basis of AGW theory is that increasing atmospheric CO2 allows the atmosphere to absorb more radiation from the land and oceans that would otherwise have escaped directly to space. Therefore, it follows that the atmosphere must warm due to the proposed increase in its radiation absorption. If it hasn’t warmed then it hasn’t absorbed additional radiation.
Mark A.
PS Excellent site Anthony, I am learning heaps.