NEW 4/10/09: There is an update to this post, see below the “read the rest of this entry” – Anthony
Guest Post by Richard Lindzen, PhD.
Alfred P. Sloan Professor of Meteorology, Department of Earth, Atmospheric and Planetary Science, MIT
This essay is from an email list that I subscribe to. Dr. Lindzen has sent this along as an addendum to his address made at ICCC 2009 in New York City. I present it here for consideration. – Anthony
Simplified Greenhouse Theory
The wavelength of visible light corresponds to the temperature of the sun’s surface (ca 6000oK). The wavelength of the heat radiation corresponds to the temperature of the earth’s atmosphere at the level from which the radiation is emitted (ca 255oK). When the earth is in equilibrium with the sun, the absorbed visible light is balanced by the emitted heat radiation.
The basic idea is that the atmosphere is roughly transparent to visible light, but, due to the presence of greenhouse substances like water vapor, clouds, and (to a much lesser extent) CO2 (which all absorb heat radiation, and hence inhibit the cooling emission), the earth is warmer than it would be in the absence of such gases.
The Perturbed Greenhouse
If one adds greenhouse gases to the atmosphere, one is adding to the ‘blanket’ that is inhibiting the emission of heat radiation (also commonly referred to as infrared radiation or long wave radiation). This causes the temperature of the earth to increase until equilibrium with the sun is reestablished.
For example, if one simply doubles the amount of CO2 in the atmosphere, the temperature increase is about 1°C.
If, however, water vapor and clouds respond to the increase in temperature in such a manner as to further enhance the ‘blanketing,’ then we have what is called a positive feedback, and the temperature needed to reestablish equilibrium will be increased. In the climate GCMs (General Circulation Models) referred to by the IPCC (the UN’s Intergovernmental Panel on Climate Change), this new temperature ranges from roughly 1.5°C to 5°C.
The equilibrium response to a doubling of CO2 (including the effects of feedbacks) is commonly referred to as the climate sensitivity.
Two Important Points
1. Equilibration takes time.
2. The feedbacks are responses to temperature – not to CO2 increases per se.
The time it takes depends primarily on the climate sensitivity, and the rapidity with which heat is transported down into the ocean. Both higher sensitivity and more rapid mixing lead to longer times. For the models referred to by the IPCC, this time is on the order of decades.
This all leads to a crucial observational test of feedbacks!
The Test: Preliminaries
Note that, in addition to any long term trends that may be present, temperature fluctuates on shorter time scales ranging from years to decades.
Such fluctuations are associated with the internal dynamics of the ocean- atmosphere system. Examples include the El Nino – Southern Oscillation, the Pacific Decadal Oscillation, etc.
These fluctuations must excite the feedback mechanisms that we have just described.
The Test
1. Run the models with the observed sea surface temperatures as boundary conditions.
2. Use the models to calculate the heat radiation emitted to space.
3. Use satellites to measure the heat radiation actually emitted by the earth.
When temperature fluctuations lead to warmer temperatures, emitted heat radiation should increase, but positive feedbacks should inhibit these emissions by virtue of the enhanced ‘blanketing.’ Given the model climate sensitivities, this ‘blanketing’ should typically reduce the emissions by a factor of about 2 or 3 from what one would see in the absence of feedbacks. If the satellite data confirms the calculated emissions, then this would constitute solid evidence that the model feedbacks are correct.
The Results of an Inadvertent Test
Above graph:
Comparison of the observed broadband LW and SW flux anomalies for the tropics with climate model simulations using observed SST records. The models are not given volcanic aerosols, so the should not expected to show the Mt. Pinatubo eruption effects in mid-1991 through mid-1993. The dashed line shows the mean of all five models, and the gray band shows the total rnage of model anomalies (maximum to minimum).
It is the topmost panel for long wave (LW) emission that we want.
Let us examine the top figure a bit more closely.
From 1985 until 1989 the models and observations are more or less the same – they have, in fact, been tuned to be so. However, with the warming after 1989, the observations characteristically exceed 7 times the model values. Recall that if the observations were only 2-3 times what the models produce, it would correspond to no feedback. What we see is much more than this – implying strong negative feedback. Note that the ups and downs of both the observations and the model (forced by observed sea surface temperature) follow the ups and downs of temperature (not shown).
Note that these results were sufficiently surprising that they were confirmed by at least 4 other groups:
Chen, J., B.E. Carlson, and A.D. Del Genio, 2002: Evidence for strengthening of the tropical general circulation in the 1990s. Science, 295, 838-841.
Cess, R.D. and P.M. Udelhofen, 2003: Climate change during 1985–1999: Cloud interactions determined from satellite measurements. Geophys. Res. Ltrs., 30, No. 1, 1019, doi:10.1029/2002GL016128.
Hatzidimitriou, D., I. Vardavas, K. G. Pavlakis, N. Hatzianastassiou, C. Matsoukas, and E. Drakakis (2004) On the decadal increase in the tropical mean outgoing longwave radiation for the period 1984–2000. Atmos. Chem. Phys., 4, 1419–1425.
Clement, A.C. and B. Soden (2005) The sensitivity of the tropical-mean radiation budget. J. Clim., 18, 3189-3203.
The preceding authors did not dwell on the profound implications of these results – they had not intended a test of model feedbacks! Rather, they mostly emphasized that the differences had to arise from cloud behavior (a well acknowledged weakness of current models). However, as noted by Chou and Lindzen (2005, Comments on “Examination of the Decadal Tropical Mean ERBS Nonscanner Radiation Data for the Iris Hypothesis”, J. Climate, 18, 2123-2127), the results imply a strong negative feedback regardless of what one attributes this to.
The Bottom Line
The earth’s climate (in contrast to the climate in current climate GCMs) is dominated by a strong net negative feedback. Climate sensitivity is on the order of 0.3°C, and such warming as may arise from increasing greenhouse gases will be indistinguishable from the fluctuations in climate that occur naturally from processes internal to the climate system itself.
An aside on Feedbacks
Here is an easily appreciated example of positive and negative feedback. In your car, the gas and brake pedals act as negative feedbacks to reduce speed when you are going too fast and increase it when you are going too slow. If someone were to reverse the position of the pedals without informing you, then they would act as positive feedbacks: increasing your speed when you are going too fast, and slowing you down when you are going too slow.
Alarming climate predictions depend critically on the fact that models have large positive feedbacks. The crucial question is whether nature actually behaves this way? The answer, as we have just seen, is unambiguously no.
UPDATE: There are some suggestions (in comments) that the graph has issues of orbital decay affecting the nonscanner instrument’s field of view. I’ve sent a request off to Dr. Lindzen for clarification. – Anthony
UPDATE2: While I have not yet heard from Dr. Lindzen (it has only been 3 hours as of this writing) commenter “wmanny” found this below, apparently written by Lindzen to address the issue:
“Recently, Wong et al (Wong, Wielicki et al, 2006, Reexamination of the Observed Decadal Variability of the Earth Radiation Budget Using Altitude-Corrected ERBE/ERBS Nonscanner WFOV Data, J. Clim., 19, 4028-4040) have reassessed their data to reduce the magnitude of the anomaly, but the remaining anomaly still represents a substantial negative feedback, and there is reason to question the new adjustments.”
I found the text above to match “wmanny’s” comment in a presentation given by Lindzen to Colgate University on 7/11/2008 which you can see here as a PDF:
http://portaldata.colgate.edu/imagegallerywww/3503/ImageGallery/LindzenLectureBeyondModels.pdf
– Anthony
UPDATE3: I received this email today (4/10) from Dr. Lindzen. My sincere thanks for his response.
Dear Anthony,
The paper was sent out for comments, and the comments (even those from “realclimate”) are appreciated. In fact, the reduction of the difference in OLR between the 80’s and 90’s due to orbital decay seems to me to be largely correct. However, the reduction in Wong, Wielicki et al (2006) of the difference in the spikes of OLR between observations and models cannot be attributed to orbital decay, and seem to me to be questionable. Nevertheless, the differences that remain still imply negative feedbacks. We are proceeding to redo the analysis of satellite data in order to better understand what went into these analyses. The matter of net differences between the 80’s and 90’s is an interesting question. Given enough time, the radiative balance is reestablished and the anomalies can be wiped out. The time it takes for this to happen depends on climate sensitivity with adjustments occurring more rapidly when sensitivity is less. However, for the spikes, the time scales are short enough to preclude adjustment except for very low sensitivity.
That said, it has become standard in climate science that data in contradiction to alarmism is inevitably ‘corrected’ to bring it closer to alarming models. None of us would argue that this data is perfect, and the corrections are often plausible. What is implausible is that the ‘corrections’ should always bring the data closer to models.
Best wishes,
Dick
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Cool. Good stuff! Nice to see Prof Lindzen make an appearance on WUWT.
PS. Can’t believe I’m the first to comment. That never happens.
Serendipity is the effect by which one accidentally discovers something fortunate, especially while looking for something else entirely.
It isn’t immediately clear why
“Given the model climate sensitivities, this ‘blanketing’ should typically reduce the emissions by a factor of about 2 or 3 from what one would see in the absence of feedbacks.”
Is this because the models generate 1.5 to 5 degrees for the one degree temperature increase of doubling CO2?
Also, “ERBS” is the acronym for “Earth Radiation Budget Satellite”
http://asd-www.larc.nasa.gov/erbe/erbs.html
For non-scanning, see third paragraph here:
http://en.wikipedia.org/wiki/Earth_Radiation_Budget_Satellite
Excellent Article. Very Clear – loved it.
From 1985 until 1989 the models and observations are more or less the same – they have, in fact, been tuned to be so. However, with the warming after 1989, the observations characteristically exceed 7 times the model values.
I would remind here that the models are tuned assuming linear approximations for the majority of variables entering the real equations ( that is what averages are). It is inevitable that as time goes on the fit becomes more and more irrelevant, because the true solutions are drastically non linear.
These data are definitive I would think on the subject of feedback.
It is interesting that the short wave has positive feedback, it ties up with what was discussed in another thread about plankton and UV and possible sun cycle effects.
What a treat, thank you Dr Lindzen.
I have often wondered whether accelerator (gas) pedals and brake pedals are reversed for you chaps who drive on the wrong side of the road. Having seen the picture I’m still unsure. Jeans and expensive shoes, that’s a tricky one for an old fart like me. Big pedal because that’s favoured by gas-guzzling wicked Americans, or big pedal because the brake has to be big to make sure they hit it from time to time? It’s all very confusing.
[snip – juvenile rant]
The fact that always seems to be bypassed in descriptions of the green house effect is that the effect has an upper limit. The greenhouse effect is due to a ‘hole’ in frequency spectrum letting in high frequency light and absorbing outgoing low frequency light. This is similar to if you had only a small hole in a spherical cavity that was the only place light could enter (i.e. a black body). The greenhouse effect essentially increases the equivalent absorptivity of earth (makes it more like a black body). However, the effect is limited. The earth can only reach an ‘equivalent’ absorptivity of 1. The earth can not absorb more light than a black body would. If you look at what the temperature of a theoretical black body would be in the position of the earth, you will see that the earth is already very close to the limit. It is already quite close to a black body and therefore very close to the maximum temperature limit it can achieve.
The first thought one might have about this (what should be obvious concept) is ‘what about Venus’? Venus temperature can not be due to greenhouse effect and must be due to something else. There are a lot of things that are unknown about Venus (such as that it has no magnetic field yet has an atmosphere, that it rotates very slowy backwards). However the concept of a runaway greenhouse effect ramping temperatures up way beyond that of an equivalent black body is false. Such a ‘one-way’ mirror effect is impossible. If it wasn’t they you would have the ability to extract energy from background heat, which you can not.
We do have runaway greenhouse effect all the time when we come out of an ice age? Isn’t it curious how temperature increase very quickly and then suddenly stop at essential the same value every time? This isn’t strange at all when one realizes that this is simple because we have hit saturation.
(see)
http://www.ianschumacher.com/maximum_temperature.html
[snip – off topic, Don you don’t get to run this thread]
[ snip – Let me make this clear, we are not going to talk about smoking and cancer on this thread, call me what you want, complain all you like here or to your buddies over at Tammy or RC, but it is not going to happen. If you have something to say about the science presented here you are welcome to say it. – Anthony]
Excellent work. But is there no data/analysis beyond 1999 to confirm the continuing negative feedback?
Great Post, are those Lucchese Ropers on the pedals?
I’m still stuck on the infared effect of a trace gases or even something more significant like water vapor. Where is the empircal data (not more self fulfilling modeling or statistics) showing this is even detectable given all the other interactions?
I believe the feedback is bigger than the effect (GHG) 😉
Certainly, from 2000 forward will be challenging for any purely statistical or ‘model based’ approach to establishing the principal interactions … regardless of the feedback.
Maybe I’m just simple but when analyzing variation in a system it is best to first establish the variation in the inputs and then look at the interactions in the process. In industry its call ‘quality control’. In science its called ’cause and effect’.
At this point I guess I’d like to thank Lindzen for some quality control.
There it is – empirical data compared to models. This type of test is a basic check to see if a model is correct. Do the modelers test their models against empirical data? This post gives me doubts.
It seems that none of the models are correct. LW feedback is negative. AGW is not cause for alarm.
Beautiful, just beautiful!
Dr. Lindzen,
Thank you for a lucid, provocative exploration of one of the critical terms of the AGW debate. You’re a credit to the profession, and that’s saying a lot, because its my distinct impression – as an informed layman – that the profession (climate studies) is currently experiencing a lack of credibility with the general public.
Thanks for posting to WUWT.
Best Regards,
-psi (Fudd, literary studies)
Anthony: I’m pleased you’ve snipped Dhogaza. I’ve been banned from RC, but I’ve seen Dhogaza over at RC say “Richard Lindzen, probably the most scientifically credible skeptic out there (tenured at MIT and all)”, then follow it up by attacks on him re smoking and cancer. There’s far too much attacking the person over at RC (see comments of Ray Ladbury, the arch personal attacker at RC) and far too little open discussion of the scientific facts.
Please feel free to snip this; it’s just my personal agreement with your policy of openly allowing discussion of the science, not the person behind it.
to Ian @ 21:45;
I think that the main temperature difference between Venus and us isn’t the difference in energy coming from the sun, it’s the surface pressure. I live in Chinook country on the Eastern slope of the rockies I can vouch for a 30 degree centigrade temperature change over about 6 hours when the chinook kicks in (quick version: air cooled over the mountains follows down the mountain slopes, pushes up against valley air and forces compression. The valley air tries to get out of the way, but can’t move fast enough. The wind monitors where I work typically have at least one 90 mph 15-second wind gust per month during the winter.)
The blackbody comparison is a good one, we tend to forget that there are lots of other systems out there we can compare against. The chaotic Jupiter weather and super-storms show that “climate change” isn’t just a terrestrial happening.
Empirical derivation of 0.3C climate sensitivity (to a doubling of CO2) is very close to what some physicists calculate from first principles.
http://www.warwickhughes.com/blog/?p=87
When theory and independant empirical observation are in agreement thats a strong indication you are close to the right number.
BTW, the GCMs (climate models) are not theories and therefore their predictions have no scientific validity. Something the IPCC completely ignores.
It’s the Evidence guys….
Hard empirical evidence – not the models, that counts.
The substitution of models as “proof” of Global Warming has corrupted the practice of science with the domain of Climate Science.
Climate Scientists need to get back in touch with Reality by testing their models (hypothesis, theory) against hard, empirical evidence.
Why they refuse to do so – they will have no credibility with me.
The AGW Proponents who read this blog/thread need to wake up to that fact that Negative Feedback is a Global Warming Killing Fact.
They then need to ask themselves why they are backing a movement that is directing resources to solve a non-problem instead of directing resources to solve real problems that matter to real people living real lives, such as poverty, hunger, illiteracy, access to clean water, etc.
Does this imply that whatever greenhouse gases are added to the atmosphere, there is no way of artificially increasing the Earth’s surface temp?
If this is true, then there is no way of stopping or even delaying the onset of the next ice age, due within the next 1000 years.
Even if the IPCC model were correct, at least AGW would have stopped the next Ice age. 5c colder is much worse then 5c warmer.
John Edmondson (22:46:34) :
Does this imply that whatever greenhouse gases are added to the atmosphere, there is no way of artificially increasing the Earth’s surface temp?
If this is true, then there is no way of stopping or even delaying the onset of the next ice age, due within the next 1000 years.
Even if the IPCC model were correct, at least AGW would have stopped the next Ice age. 5c colder is much worse then 5c warmer.
That’s right – Europe and North America do not have a viable future – barring the invention of some amazing new technologies….
Mind you in Australia, Ice Ages provide more water and lush rain forests will cover much of the east coast…
Ian Schumacher (21:45:21) :
The fact that always seems to be bypassed in descriptions of the green house effect is that the effect has an upper limit. The greenhouse effect is due to a ‘hole’ in frequency spectrum letting in high frequency light and absorbing outgoing low frequency light. This is similar to if you had only a small hole in a spherical cavity that was the only place light could enter (i.e. a black body). The greenhouse effect essentially increases the equivalent absorptivity of earth (makes it more like a black body). However, the effect is limited. The earth can only reach an ‘equivalent’ absorptivity of 1. The earth can not absorb more light than a black body would. If you look at what the temperature of a theoretical black body would be in the position of the earth, you will see that the earth is already very close to the limit. It is already quite close to a black body and therefore very close to the maximum temperature limit it can achieve.
….
(see)
http://www.ianschumacher.com/maximum_temperature.html Ian Schumacher
I went to your link. Interesting pov, and cannot see a logical error.
Would you say that the negative feedback shown by the data here is the beginning of an ice age? :).
What about that the total SW +LW is on the positive feedback side. How does it fit in the way you look at it, with band filters? That there exists another band except green house gases? ( could be the effect of the plankton :))
Sorry sorry that is ” can see NO logical error”!!!
[Not to worry. Either is correct. ~ Evan]
John Edmondson (22:46:34) :
Does this imply that whatever greenhouse gases are added to the atmosphere, there is no way of artificially increasing the Earth’s surface temp?
If this is true, then there is no way of stopping or even delaying the onset of the next ice age, due within the next 1000 years.
Even if the IPCC model were correct, at least AGW would have stopped the next Ice age. 5c colder is much worse then 5c warmer.
Never underestimate geoengineering. Badgers have done it and humans won’t be able to?
Ways will be found to decrease albedo or increase incoming sunshine, if we manage to reach that time out of the stone age, where the AGWers are determined to take us.
The entire debate hangs on two issues: feedbacks and data integrity. Without positive feedback, runaway GW theory crumbles. Same, if the data is biased.
(It seems that for AGW, it’s two strikes, you’re out. More study is needed, of course, but that’s the way the wind seems to be blowing.)
Anthony and all- Kudos to Dr. Lindzen for a clear, accessible, and enlightening post. Love the surprise ending confirming something many of us have long suspected- that the strong positive feedbacks predicted by IPCC are clearly “non-operable”. Wanted to check if others had seen the full-page Cato Institute sponsored letter to the President signed by many, including quite a few folks who are regular contributors, posters, or topics of discussion here and at CA. Ran into it in today’s LA Times, page A17. Highly recommend. Many who feel as we do are willing to risk the slings and arrows of an entrenched industry of doomsayers. I feel the “tipping point” AGW proponents will have to deal with is not the one they expected. Our point of view is gaining traction, day by day. Thanks Anthony for hosting a major touchstone in the movement to restore reason to the public debate.
Graeme Rodaughan (22:55:26) wrote in part: “Mind you in Australia, Ice Ages provide more water and lush rain forests will cover much of the east coast…”
Steady, Graeme. You could break a lot of hearts with statements like that. Australia is fragile. Australia is doomed. You must imprint that on your mind. Drink only seawater (I think that’s what causes the hallucinations) and get back into the mainstream.
One thing that puzzles me in the environmental movement with regard to feedback is Gaia theory as proposed by James Lovelock which as defined in wiki http://en.wikipedia.org/wiki/Gaia_theory says:
“The Gaia hypothesis is an ecological hypothesis proposing that the biosphere and the physical components of the Earth (atmosphere, cryosphere, hydrosphere and lithosphere) are closely integrated to form a complex interacting system that maintains the climatic and biogeochemical conditions on Earth in a preferred homeostasis.”
This sounds quite elegant to me, that the biological and geological activity produce a feedback system which unlike our neighbors Mars and Venus has kept the earth in a state which allows life to exist. It goes on to say:
“Some relatively simple homeostatic mechanisms are generally accepted. For example, when atmospheric carbon dioxide levels rise, the biomass of photosynthetic organisms increases and thus removes more carbon dioxide from the atmosphere, but the extent to which these mechanisms stabilize and modify the Earth’s overall climate are not yet known.”
So my reading of Gaia theory says nothing to worry about the earth is full of feedbacks which keep thing relativelyly stable. Problem solved, now lets have a nice cup of tea.
However James Lovelock seems to have a different vision, he seems to see humans as a cancer. Here is a quote from a recent interview:
“Because of this (AGW), the cull during this century is going to be huge, up to 90 per cent. The number of people remaining at the end of the century will probably be a billion or less.”
http://www.newscientist.com/article/mg20126921.500-one-last-chance-to-save-mankind.html
I dont understand how i can look at a theory and come to the exact opposite conclusions of the person who proposed it.
So we now have this, and the lack of the tropical troposphere hot spot and the lack of increasing ocean heat content and yet still, flying in the face of correct scientific method, the models are still accepted, because a lot of scientists in key positions really believe them to be true.
Also another thought, if the earth’s climate was inherently unstable and increasing CO2 causes increasing temperature which in turn causes further increasing temperature then, given that the paleoclimate record suggests that temperature drives CO2 increase wouldn’t the climate have spiralled out of control millennia ago?
The work of Michael Hammer (Jennifer Marohasy’s site 3rd March) may provide the mechanism for a lack of positive feedback suggested here. He describes how most of the energy lost from the earth is at wavelengths not absorbed by greenhouse gases. He also replies to a comment concerning correlation of his theories with satellite data.
He concludes:
‘Both the analysis from basic spectroscopy and the analysis based on atmospheric lapse rates give similar results and imply that greenhouse gases almost totally block energy loss to space at their absorption/emission wavelengths. That in turn suggests that a very significant portion of the energy loss from Earth’s surface is by direct radiation to space at wavelengths where the greenhouse gases do not absorb.’
‘This is in conflict with the Kiehl & Trenberth model and other similar models which suggest that most of the energy loss to space is from the atmosphere. If the atmosphere emits little energy, and then largely from the tropopause and stratopause, the concept of an equivalent radiation altitude has no meaning. Further, the analysis suggests that most of the radiative energy loss from the atmosphere to space is re-radiation of solar energy absorbed high up in the atmosphere.’
‘Surface temperature will increase with increasing greenhouse gas concentrations due to line broadening. The direct effect of carbon dioxide (in the absence of any feedbacks) using the IPCC quoted sensitivity and their postulated rise in carbon dioxide from 390 ppm to 560 ppm will contribute 0.4 degrees by 2070. The IPCC claim that positive feedback from water vapour will increase that to about 3C would imply a sensitivity of 48 watts/m2 per doubling in water vapour concentration. Such a high sensitivity is not compatible with the observed atmospheric temperature versus altitude profile.’
‘It should be noted that this analysis does not predict no radiation to space at the greenhouse gas absorption lines. There is still energy at these absorption lines emitted to space. For the well mixed greenhouse gases such as CO2 and CH4 this energy largely emanates from the stratosphere and is powered significantly by UV absorption of incoming solar radiation by ozone plus some absorption of surface radiation at 9.6 micron . In the case of water vapour, the energy emanates from near the tropopause and is powered significantly by near infrared absorption of incoming solar radiation by water vapour.
“The Results of an Inadvertent Test”
Insight is Beauty. Beauty is Insight.
Wow.
Thank you, Dr. Lindzen.
Probably goes without saying, (but I neglected to). Text and pdf copies of the Cato ad are up on their site, http://www.cato.org, for anyone interested. Thanks- JG
So why should we expect models forced by ocean temperature changes instead of (or is that on top of) Co2 etc to match what the IPCC models, based on the forcings of Co2, but not including any forcings for SST changes predict?
@FatBigot: In case you were being serious, the americans have their pedals the same way around as us. The big one is there because they tend to drive automatics and need somewhere to put their clutch foot when they’re emergency breaking.
And, is it me, or is the posh shoes guy in the picture going to end up wasting loads of fuel from riding the brakes all the time?
And isn’t it a beautiful wind, evenmjones?
Wow, great stuff! (Sorry, can’t offer anything more intelligent to say.)
Isn’t this amazing, as the temperature goes up, negative feedback goes up. As the temperature goes down, the feedback starts going positive.
Just like my car; when I see my speed going over the speed limit, I let up on the gas and perhaps, if necessary, apply the brakes. If I’m going too slow, I reverse the process.
I’m sure we could all think of several other systems with built in feedbacks intended to keep some parameter within range.
It almost seems as if the earth, like automobiles and home heating systems, were designed to maintain a comfortable environment for life.
Looks like Hansen has decided that the models are no good after all quoted from
http://www.examiner.com/x-2534-SF-Wellness-Examiner~y2009m3d29-James-Hansen-sets-the-record-straight-on-the-New-York-Times-article-The-Civil-Heretic
“I looked up Freeman Dyson on Wikipedia, which describes his views on “global warming” as below. If that is an accurate description of what he is saying now, it is actually quite reasonable (I had heard that he is just another contrarian). However, this also indicates that he is under the mistaken impression that concern about global warming is based on climate models, which in reality play little role in our understanding — our understanding is based mainly on how the Earth responded to changes of boundary conditions in the past and on how it is responding to on-going changes”.
I would say that the scientist leading the AGW’res have about 12-24 months before their careers are terminated or they will be required to change “research activities” LOL
It would seem that Dr Lindzen is far more qualified as well to make statements about AGW…LOL
http://www.giss.nasa.gov/staff/jhansen.html
“cloud behavior (a well acknowledged weakness of current models)”
recent research from NASA on clouds and aerosols:
http://www.newscientist.com/article/dn16864-halo-effect-explains-brightest-patches-of-sky.html
Excellent, first class. A calm look at reality is what is always needed.
Slightly OT then, IF we’re headed for a new ice age within 1,000 years, is there some organisation that can take the UN & its IPCC & the WMO to task for overt ignorance of this basic fact of life, & sue the hell out of them for shear incompetence! Anyway the south west of England should be realitvely ice free, but rather crowded!!!! I’d better get practicing the flint napping.
Brilliant. A tour-de-force.
Mike Guerin (23:29:36) :
“Is it just me? Am I that smart and everyone else that stupid. Isn’t it obvious that for life to exist on earth there must be a strong negative feedback effect in place. Without strong negative feedback does anyone sane really think that the climate on earth would remain stable enough long enough for life to evolve and prosper?”
Mike, no you’re not the only one!
If the theory behind AGW is correct, the logical conclusion is that the natural response of the earth to an increase in heat is to effectively “turn the thermostat up”
Clearly, we wouldn’t be here today if that was the case!
Of course, to increase the rate of radiation to space, it is also logical that the atmosphere would increase rapidly in temperature to facilitate this, but this shouldn’t be mistaken for runaway positive feedback.
The subtlety with AGW propaganda is that it is a self-reinforcing mechanism:
1/ climatologists validate their climate reconstructions by noting that they agree with the models ;
2/ in IPCC’s reports, models are valid because they agree with past climate reconstructions.
They can not be wrong.
Bye,
TMTisFree
It’s common sense that there is negative feedback. This is what keeps the climate fairly stable.
If there was positive feedback, then the climate would be unstable – and would have been de-stabilised by now with disastrous consequences.
Clear, concise…… A bell tolling the end of a hypothesis that should have been falsified ten years ago. Good on you Dr Lindzen.
Now. considering that the reality has been Politics and not Climate….
Is our democracy strong enough to override the massive political impetus that AGW has built up….? After all, there is a whole green Socialist agenda relying on those carbon taxes and emission trading schemes…. and the careers of those that have attached themselves to a lie. Whole industries are gearing up to go green.
It will be an interesting time ahead.
Another approach with a similar answer.
EXTRAPOLATING OBSERVED WARMING TRENDS
by Jarl Ahlbeck (Turku, Finland) (done in 2005 or earlier)
We should not confuse the word “possibility” with “probability” as some
people do when they compare different simulated results with each other.
Everything is possible, but probability has a mathematical definition and
should not be used when comparing simulated results. These reported
(Nature, 27 Jan 2005) values of 1.9 to 11.5 deg C warming are
possibilities, computerized speculations, nothing else. Also: Let’s not
to talk about percent possibilities. All possibilities are
100% possible.
But of course, a kind of reality check can be made very easily: Say that
half of the observed 20th century warming of 0.8 deg is due to greenhouse
gases (CO2 increase from 280 to-370 ppm) and half is due to increased sun
activity. As the relation is logarithmic, 0.4 deg=k*ln(370/280), giving
k=1.435. For 2*CO2 (560 ppm), an additional warming of 1.435*ln(560/370) =0.59 deg C could be expected. This is a speculation as good as any
produced by a computer climate entertainment program.
In fact, 0.59 deg may be an overprediction as the observed warming has been
partly caused by CFCs and CH4. As we know, the atmospheric concentration of CFC has decreased, and there is no more increase in CH4. This means that
the k-value for CO2 should be lower than 1.435.
k = deltaT/ln(CO2b/CO2a)
deltaT = k*ln(CO2b/CO2a)
For various % of 0.8 degree C temp rise in 20th century ascribed to CO2:
(MacRae calculations and comments below)
k CO2a CO2b deltaT
As Above Case
1.435 280 370 0.4 checks Assumes 50% deltaT
1.435 370 560 0.595 checks due to >CO2.
2.870 280 370 0.8 Assumes 100% deltaT
2.870 370 560 1.189 due to >CO2.
Both 50% and 100% seem too much high, given the better correlations below.
0.718 280 370 0.2 Assumes 25% deltaT
0.718 370 560 0.298 due to >CO2.
From ~1850-1940, NH temperature rose by ~0.6 deg prior to the period of CO2 and fossil fuel growth – is the best correlation a “+25% deltaT” = i.e. plus 0.3 degrees?
0.000 280 370 0 Assumes 0% deltaT
0.000 370 560 0.000 due to >CO2.
Given the excellent correlation between NH temperature and solar activity since at least 1750, it is plausible that temperature is completely insensitive to CO2 level.
-0.718 280 370 -0.2 Assumes -25% deltaT
-0.718 370 560 -0.298 due to >CO2.
From 1940-1975, NH temperature fell by ~0.2 deg during the highest period of CO2 and fossil fuel growth – is the best correlation a “-25% deltaT” = i.e. minus 0.3 degrees?
Informal conclusions:
Best fit approx. 0, +/- 0.3 degrees C for a doubling of CO2.
Even doubling CO2 is a non-issue – dump Kyoto and focus on real problems.
****************************
Graeme Rodaughan (22:55:26) :
quote Does this imply that whatever greenhouse gases are added to the atmosphere, there is no way of artificially increasing the Earth’s surface temp?
If this is true, then there is no way of stopping or even delaying the onset of the next ice age, due within the next 1000 years. unquote
I have seen The Great Slave Lake only on radar, but it has always fascinated me: now I can think of a reason to go there. One can use it to test what’s going on in the Arctic Ocean. Give me a budget of a few tens of millions and this is what I’d do: check the water surface for pollution, particularly light oil and surfactant contamination, either clean it up or dirty it more and check the emissivity as night falls. Oil and surfactant smooth water. Smoothed water should warm faster during daylight and cool slower at night. Easily monitored from the air. It might explain the warming of Lake Superior, even though the experiment is too limited to check the stratocu effect which I’d expect over the open sea.
Then check off the North Slope and around Sakhalin for the same level of pollution. Yes, feedback is probably negative, but e pur si muove — something’s causing the warming and my bet is oil and surfactant.
Count them, four peer-reviewed papers saying that commonsense will eventually prevail. Thank you Professor Lindzen. BTW (insert smily here) you do know that the Met Office graph you used has got the dreaded Folland and Parker bucket correction incorporated and thus suppresses the abrupt warming in 39/40? This hides the…. (covers head, runs, a faint wail of ‘Kriegesmarine effect’ drifts away on the breeze….)
Graeme, if you want to stop an Ice Age, just pump more oil and Tide onto the parts of the ocean which are warming most rapidly — the big gyres look interesting. It’s happened before — I’m not sure how you’d check for a natural breaching of a major oil reservoir during the PETM, but for a few million more I’ll put my thinking cap on.
JF
.3? I’d have bet a pint on .6.
It does seem that climate feedback is of huge importance, and it is this that may provide the nails for the coffin of strong AGW. But which dominates, positive or negative? The fact that i am sitting at my desk and typing this strongly suggests that negative feedback dominates.
In my professional career spanning several decades I have had a lot of experience with servomechanisms, which use negative feedback to achieve a desired result. A badly designed or faulty system will still broadly achieve the desired result, such as maintaining a commanded position. But it will tend to oscillate, sometimes with a simple harmonic motion or a far more complex and apparently random motion. It will respond badly to external influences. But overall it will maintain the desired result.
Looking at graphs of climate, I’m reminded of a poorly designed servomechanism. The climate often oscillates and responds poorly to outside effects such as earthquakes. When returning to the ‘commanded’ position it will often overshoot quite badly. But it does return, so that the overall global temperature over the last few thousand years has been remarkably stable, with variations measured mostly in fractions of a degree.
Clearly the global climate is a servomechanism. And servomechanisms work by negative feedback. I think Professor Lindzen’s work is of extraordinary importance.
Chris
Tech note, mes amis:
You can get the Degree symbol º on a PC keyboard by holding down the Alt key and typing 167 in the numeric keypad. Release the Alt key, and the º appears. Google “alt characters” to find listings of other characters.
.
Ian Schumacher (21:45:21) :
. . . The first thought one might have about this (what should be obvious concept) is ‘what about Venus?’ Venus’ temperature can not be due to greenhouse effect and must be due to something else.
Another Mike D (22:39:57) :
I think that the main temperature difference between Venus and us isn’t the difference in energy coming from the sun, it’s the surface pressure. . . .
Right. Temperature decreases with altitude as the pressure decreases, and vice versa. The temperature lapse rate has to do with the specific heat ratio of the gasses involved, very close to 1.4 for air, and between 1.2 to 1.3 for Venus’ CO2 atmosphere. Venus has 90 times earth surface pressure (90 bar), with a resulting high temp. The odd thing here is that with the different lapse rate, if Venus had a 90 bar AIR atmosphere, its surface temp would be a couple hundred ºC hotter, just the opposite of the runaway CO2 greenhouse image commonly peddled.
As close to the sun as Venus is, I’d guess its high albedo is responsible for the temps not being as high as they might otherwise.
.
Thank you Dr Lindzen. On a related area, CO2 has only an absorption band around 4 microns that it doesn’t share with water. According to the atmospheric transmission charts, there isn’t much energy up or down in that region. Are the satellites like ERBS capable of measuring how much 4 micron radiation is reaching the satellite from earth? That would be how much energy remains for CO2 to capture, and thus an upper limit to how much additional heat the doubling of CO2 could add. From the charts, it doesn’t look like much.
“The most tragic thing in science is that a beautiful theory can be slayed by one ugly fact”. Thank you, Dr. ‘Dagonslayer’ Lidzen.
All:
As several have noted, Prof. Lindzen provides a clear and cogent case that empirical evidence indicates negative feedback in the climate system.
Paleo data indicates the same.
The Sun is a g-type star and observation of such stars indicates they get hotter as they age. For this reason, direct radiative forcing of the Earth’s climate by the Sun must have increased by ~30% in the 2.5 billion years since the Earth acquired an oxygen-rich atmosphere. Therefore, if the climate system had no feedbacks then the oceans would have boiled to steam by now. Indeed, the climate system has been bi-stable (i.e. stable in glacial and interglacial states) with remarkably little temperature difference in each state throughout geological ages.
For nearly three decades I have been asking AGW-advocates why ~0.4% increase to radiative forcing from a doubling of carbon dioxide is feared when ~30% increase to radiative forcing from the Sun has had no discernible effect. To date, I have not had a sensible answer.
Richard
Archonix (00:27:40) :
@FatBigot: In case you were being serious, the americans have their pedals the same way around as us. The big one is there because they tend to drive automatics and need somewhere to put their clutch foot when they’re emergency breaking.
We Americans drive big cars. We don’t brake for nuthin’.
Mike Guerin (23:29:36) :
Is it just me? Am I that smart and everyone else that stupid. Isn’t it obvious that for life to exist on earth there must be a strong negative feedback effect in place. Without strong negative feedback does anyone sane really think that the climate on earth would remain stable enough long enough for life to evolve and prosper?
Mike – you are not alone. The premise of a world climate that oscillates about a mean driven by Negative feedbacks and providing a mostly stable environment conducive to life for many millions of years is a common idea.
The problem that I have is the premise that this stable, natural variation has been turned on it’s head within the last 100 to 150 years (AGW).
It’s an extraordinary claim and requires extraordinary evidence – and not even ordinary evidence is available to support it (AGW).
Roger Carr (23:46:56) :
Graeme Rodaughan (22:55:26) wrote in part: “Mind you in Australia, Ice Ages provide more water and lush rain forests will cover much of the east coast…”
Steady, Graeme. You could break a lot of hearts with statements like that. Australia is fragile. Australia is doomed. You must imprint that on your mind. Drink only seawater (I think that’s what causes the hallucinations) and get back into the mainstream.
Ha Ha…. Australia will Rule the next (Frozen) Millenium (Post 3000 AD). Just take my word for it……
Richard Heg (23:48:31) :
One thing that puzzles me in the environmental movement with regard to feedback is Gaia theory as proposed by James Lovelock which as defined in wiki http://en.wikipedia.org/wiki/Gaia_theory says:
“The Gaia hypothesis is an ecological hypothesis proposing that the biosphere and the physical components of the Earth (atmosphere, cryosphere, hydrosphere and lithosphere) are closely integrated to form a complex interacting system that maintains the climatic and biogeochemical conditions on Earth in a preferred homeostasis.”
This sounds quite elegant to me, that the biological and geological activity produce a feedback system which unlike our neighbors Mars and Venus has kept the earth in a state which allows life to exist. It goes on to say:
“Some relatively simple homeostatic mechanisms are generally accepted. For example, when atmospheric carbon dioxide levels rise, the biomass of photosynthetic organisms increases and thus removes more carbon dioxide from the atmosphere, but the extent to which these mechanisms stabilize and modify the Earth’s overall climate are not yet known.”
So my reading of Gaia theory says nothing to worry about the earth is full of feedbacks which keep thing relativelyly stable. Problem solved, now lets have a nice cup of tea.
However James Lovelock seems to have a different vision, he seems to see humans as a cancer. Here is a quote from a recent interview:
“Because of this (AGW), the cull during this century is going to be huge, up to 90 per cent. The number of people remaining at the end of the century will probably be a billion or less.”
http://www.newscientist.com/article/mg20126921.500-one-last-chance-to-save-mankind.html
I dont understand how i can look at a theory and come to the exact opposite conclusions of the person who proposed it.
Is he a closet Malthusian?
Does it increase his social status to jump on board the latest alarmist craze?
Does he feel validated?
Inquiring minds would like to know.
Alan the Brit (01:06:38) :
Excellent, first class. A calm look at reality is what is always needed.
Slightly OT then, IF we’re headed for a new ice age within 1,000 years, is there some organisation that can take the UN & its IPCC & the WMO to task for overt ignorance of this basic fact of life, & sue the hell out of them for shear incompetence! Anyway the south west of England should be realitvely ice free, but rather crowded!!!! I’d better get practicing the flint napping.
The Brits will just have to migrate to the Costa del Sol and other locations on the Spanish Coast…
Whoops – that’s already happening – this Impending Ice Age must be closer than we think…
This seems very much in line with what Dr Roy Spencer is saying.
vg (00:45:39) :
….
I would say that the scientist leading the AGW’res have about 12-24 months before their careers are terminated or they will be required to change “research activities” LOL
One could hope – however AGW is a very well funded and powered movement, and it will take significant public backlash before the Politicians sit up and take notice… and that’s still to happen.
Dr. Lindzen has just falsified a key postulate of Anthropogenic Global Warming. Now we will see if the AGW proponents are scientist or just cheap politicians hustling for a dime.
Seriously, this is very big. Congratulations Dr. Lindzen and a hardy way-to-go Anthony!
–Mike Ramsey
vg (00:45:39) :
Looks like Hansen has decided that the models are no good after all
I find that amazing. So he’s now saying that the empirical evidence supports AGW and is the main basis for his predictions, not the models? This really is game over Hansen.
By the way, this was an excellent article by Richard Lindzen.
If I am getting all of this correct: The satellites measured the shortwave coming from the Sun, and the longwave being lost by the Earth, and found equilibrium. Is that right? In the case of clouds (water vapor) the satellites could meause both the longwave coming through and the shortwave that was reflected (never reaching the ground) and again found equilibrium.
Is that also right?
So, if all of that above is correct, then Archibald is correct when he says that if the AGW’er ever manage to find a way to remove the CO2 from the atmosphere, they will throw the baby out with the bathwater and both will freeze up.
One of the factors used by the IPCC in stating the 90% certainty for human causation of global warming is that the forcing of 3.71watts/m^2 from a doubling of CO2 falls between the 5 and 95 percentiles from the model outputs. Since 5.35ln(2) equals 3.71 it is quite clear that the GCM models are designed to confirm the forcing parameter of the original Hansen model from the 1988 paper. Essentially this parameter was invented to introduce CO2 forcing into the existing climate models in such a way as to demonstrate potential catastrophic warming where none exists. The basis for this was the assumption that natural warming of 0.6°C was caused entirely by CO2 increases which were attributed to fossil fuel emissions (even though the source of these emissions is mostly due to outgassing of CO2 from warming oceans).
The forcing parameter that resulted was
5.35ln(current CO2)/(reference CO2) which leads to a value of 3.71 for a doubling. To use the analogy of the accelerator and the brake this formula does not have a brake and only shows increasing forcing with increasing CO2. The conversion from watts/m^2 to temperature is accomplished with the factor 0.75°C/watt resulting in basic warming of 2.78°C for a doubling of CO2. Since 2002 the concentration of CO2 has gone from about 374ppmv to 386ppmv. The forcing parameter of 5.35ln(386/374) * 0.75 shows that there should have been an increase in global temperature increase of 0.0236°C but the satellite temperature data show that the temperature cooled by about 0.15°C since 2002. The cooling is six times the rate and in the opposite direction of the predicted temperature of the models. This means that even if the models were actually based on fact feedback systems not included in the models dominate the effect tyo the point that the predictions of the models are irrelevant.
Norm K.
As for this link:
http://www.ianschumacher.com/maximum_temperature.html
SDSS found to thier dismay that u filters they placed inside the cooled chamber with the imaging chip (CCD) changed in properties due to being in a vacuum.
http://www.sdss.org/dr6/products/images/index.html#redleak
There is also some stuff in there about airmass and UV.
Now, that’s an empirical test with a real live filter set.
Surely the climate is a metastable system as indicated by ice core records etc:
Super ice age (snow ball earth)(?)
Ice age -2degC
warm age 0degC
Hot age(?) +2degC 40Mybp +8degC 400Mybp
Positive feedback is not an unlimited effect GHGs have logarithmic effects enabling the negative FBs (plant growth, radiation balance etc) to re-take control.Methane trapped in frozen tundra may be released if the temperature increases. CH4 in the atmosphere has a life of about 4 years. So the tipping point when these are released may only produce a pulse of high temeratures for a couple of decades.
However this may be long enough to melt land based ice reducing the albedo and adding to the positive FB. However these effects are self limiting – plant growth, radiation balance (a hotter earth = more heat radiated but same heat input) will attain a new stable temperature.
The question is what will this be? and what will reduce the climate back to the current metastable state?
Graeme Rodaughan @ 22:55:26
Right, I’m moving to Australia in 3 thousand years 🙂
Thank you Jack, and others that have pointed this out! Finally, some talk about this mechanism, what I call the “impossible tipping point” mechanism. When I first heard the words “tipping point” as it pertains to AGW, I think it triggered my tipping point in the AGW debate. I believe it to be physically impossible on this planet (perhaps any other for that matter) to have a “tipping point” and “runaway greenhouse effect”. Common sense simply tells you this is so, yet one of the fundamental drivers of the AGW theory requires a “tipping point”. There very fact that this “tipping point” cannot exists, for me, completely invalidates the entire theory of AGW, and it didn’t take any kind of model to deduce this very simple observation.
Just look at the recent articles here.
Chip, chip, chip… the stone wall that has been erected around the false science of AGW is being torn down. The poliscis better climb aboard the train of life and leave the AGW hoax while the getting is good.
Thanks, Anthony, for helping to shine the spotlight of truth into the putrid corners of what passes for science today.
Mike
Pffft….this is all a moot point
The AGW propagandists dont care about facts or science. The AGW cause is nothing but a means to spread and enforce the socialist green religious ideology of the modern left.
The MSM media will never ever report these facts. Not unless criminal/legal action is taken against the journalsits and their editors. I dont know if there is a legal basis for this (eg Treason laws). But make no mistake. NOTHING, EVER will make the left wing MSM media report on these facts.
With the exception of a small few in the media (like Andrew Bolt in Australia), most journalists are dedicated “modern socialists” who will do and say what ever is necessary to promote the modern left wing socialist religion/ideology.
We are doomed to live our lives under strict control unless action is taken against those in the media promiting this.
Clear and lucid and what Miskolczi has been saying; not to mention Spencer and Steve Short and… everyone except IPCC and its associates.
It would be nice to see an AGWer with a scientific argument against this presentation so we can find out their objections, valid or otherwise. Will it happen? From what I’ve seen so far, despite their oft-stated commitment to science, it’s not clear if any of them even read what Lindzen has ever written; they seem just to expound that RC says Lindzen has been rebutted and that’s all they need. I wait with baited breath, the educated rebuttals.
Very good article-I see the Warmists going off the rails daily.I also see the common
folks-believing less and less of it.Fargo,for instance is NOT a Warming event…
Dr. Lindzen, thank you very very much for your work and your posting.
Anthony, please have a look at this amazing picture:
http://spaceweather.com/submissions/large_image_popup.php?image_name=Brian-Whittaker-www-BrianWhittaker-com-Redoubt-Ash_1238432595.jpg
Also have a look at the SO2 graph
http://www.spaceweather.com/
Thanks
O/T Sir Nicholas Stern is shortly due on Radio Five Live in the UK (14:30 BST) talking about Climate Change and his new book. I’m preparing my email now !
Kind of a IPCC “adjusted” new greenhouse theory. Where is it the original paper?, how much time lasts the isotherm?
Clear, concise and to the point. Well written article and (as with many other recent findings) should help in putting a check on the insanity bandwagon that we are on currently.
Thank you Dr Lindzen and Anthony – keep up the good work, and most importantly keep the light of objective science burning…
There’s a typo beneath “The Results of an Inadvertent Test”:
“so the should not expected”
should be “so they should not be expected”
A somewhat open minded BBC radio interview with Roger Harrabin (he who capitulated to the demands of eco-campaigner Jo Abbess) and Vicky Pope. You might want to run this one as a new blog entry, Anthony
Around the 10 minute mark the presenter displays some scepticism.
http://news.bbc.co.uk/today/hi/today/newsid_7936000/7936645.stm
As a result, the radio show presenter has been rapped by the Ends Report and John Vidal of the Guardian for being open minded
http://www.guardian.co.uk/environment/blog/2009/mar/31/james-naughtie-ends-report-climate-scepticism
This has been bothering me for a while: I’m a controls engineer, modeling of physical systems [very simple ones compared to the atmosphere] is most of what I do.
There is no such thing as a stable system who’s behavior is dominated by positive feedbacks. That’s pretty much the definition of positive feedback. Yet the AGW theory, as I understand it, maintains that Earth’s temperature was fairly stable until sometime in the industrial age, then started warming due largely to positive feedback on temperature. Obviously something else is going on, as there must have been some mechanism that stabilized temperature in the past.
Furthermore, if you did have a system that was somehow balanced on an unstable node, and you disturbed it, it would fall away from that node. Removing whatever disturbed it wouldn’t return it to the node, it wouldn’t even stop the system moving away from it (you can’t un-disturb the system). In other words, if world temperature were dominated by positive feedback, and CO2 did disturb the precarious balance, even if we completely halted CO2 emissions, that wouldn’t stop the runaway warming. ANY disturbance of a positive feedback system is a “tipping point.”
“Excellent, first class. A calm look at reality is what is always needed.”
But it hasn’t been peer-reviewed, nyah, nyah!
And it’s by a middle-aged white male!!
with ties to the Heartland Institute!!!
Case closed.
There are some problems in this analysis.
1. The Radiative Anomalies in the y-axis isn’t defined.
2. The author states, “the observations characteristically exceed 7 times the model values” but doesn’t explain how he arrived at this conclusion. The graph shows only one data point above or near 7 which is not sufficient data to make the claim.
3. The author then seems to use this one data point to make the conclusions in the paragraph titled, Bottom Line.
How did the climate modelers ignore the data from this experiment?
It was specifically designed to confirm or modify the very, very basic designs/theory surrounding the models – the greenhouse effect itself.
How come we haven’t heard about this before? They must have decided to bury it when it didn’t confirm the theory/models but actually said they needed to go back to the drawing board.
It is almost like (it is exactly like) any data which does not conform to their view is ignored, discredited through various strawman arguments or subsequently changed afterward.
But, what we are really interested in is overall net feedback (SW plus LW), not just LW. I believed it is also negative and Lindzen says so, but looking at the graphs he presented show that SW feedback is stronlgy positive as well as overall feedback which is also on positive side (3rd panel). Is there anything I don’t understand correctly?
Mike Guerin (23:29:36) :
Isn’t it obvious that for life to exist on earth there must be a strong negative feedback effect in place. Without strong negative feedback does anyone sane really think that the climate on earth would remain stable enough long enough for life to evolve and prosper?
Jack Hughes (01:31:30) :
If there was positive feedback, then the climate would be unstable – and would have been de-stabilised by now with disastrous consequences.
The sign of the feedback coefficient does not indiciate stability or instability. Feedback can be positive and produce a stable system. Feedback can be negative and produce an unstable system.
Fortunately, it appears that in the earth climate system vapor+cloud feedbacks are net negative and stable.
Thank you Anthony and Dr. Lindzen. Through this blog I am getting the semantics to piece together what has been intuitively obvious. If our climate was unstable as the AGWers want us to believe, we would not be having this discussion. When mass extinctions have happened via extraterrestrial impacts or volcanoes, there surely was enough biomass to generate ‘greenhouse’ gases in excess of anything we produce. To the best of our knowledge, CO2 has been in the 5-6000ppm range without a runaway system, and without climate being much warmer. This means as others pointed out above, there is an upper limit to climate temperature. This has to be, lacking a major fluctuation from the only local heat source, the sun.
Our importance is highly over-exaggerated, and as regards climate, there is nothing new under the sun. It appears we are at or near maxium temperature for this planet, so we need to appreciate it while we can. As pointed out by others here, warm is better than cold. The hysterics over runaway heating is silly on the one hand, and just another a political ploy on the other. Many in the illusory position of power remain there by playing on the ego-centric nature of humans that is extrapolated to the near omnipotent effect our presence must have on our environment. This is exaggerated too by the false sense of esteem bestowed on the past generation or two via reward for nonachievement through our education and welfare systems. Herein lies a runaway system effect, false fear in the masses = money and power for the elite.
Roger Knights (05:29:30) :
“Excellent, first class. A calm look at reality is what is always needed.”
But it hasn’t been peer-reviewed, nyah, nyah!
“Note that these results were sufficiently surprising that they were confirmed by at least 4 other groups:
Chen, J., B.E. Carlson, and A.D. Del Genio, 2002: Evidence for strengthening of the tropical general circulation in the 1990s. Science, 295, 838-841.
Cess, R.D. and P.M. Udelhofen, 2003: Climate change during 1985–1999: Cloud interactions determined from satellite measurements. Geophys. Res. Ltrs., 30, No. 1, 1019, doi:10.1029/2002GL016128.
Hatzidimitriou, D., I. Vardavas, K. G. Pavlakis, N. Hatzianastassiou, C. Matsoukas, and E. Drakakis (2004) On the decadal increase in the tropical mean outgoing longwave radiation for the period 1984–2000. Atmos. Chem. Phys., 4, 1419–1425.
Clement, A.C. and B. Soden (2005) The sensitivity of the tropical-mean radiation budget. J. Clim., 18, 3189-3203.”
Not sure what your point was.
–Mike Ramsey
Excellent article – but I have a question. If the Earth’s climate is dominated by negative feedbacks, how does the Eocene warming episode of 55 million years ago (PETM) fit into this? I often see it mentioned as an example of positive feedback at work.
Biased CBC reporting (read it all).
Fire. Them. All.
Notice CBC attempts to deflect the reader by using words e.g. “Pricey ads”, etc.
Fire. Them. All.
…-
“Pricey ads signed by scientists slam Obama’s climate change talk
More than 100 scientists — including a number of Canadian government scientists and university professors — have signed a full-page newspaper ad denouncing U.S. President Barack Obama’s remarks about climate change last November as “untrue.”
“The Cato Institute ad takes issue with the following statement, made by U.S. President Barack Obama on Nov. 19, 2008:
“Few challenges facing America and the world are more urgent than combating climate change. The science is beyond dispute and the facts are clear.”
“Mr. President , your characterization of the scientific facts regarding climate change and the degree of certainty informing the scientific debate is simply incorrect,” said the ads paid for by the Cato Institute that ran Monday in the New York Times, the Washington Post, the Washington Times, the Chicago Tribune and the Los Angeles Times. The ads cite evidence, referenced in four scientific papers, that the climate is not changing significantly.”
“Among the Canadians who signed the ad were:
* Ian Clark, professor of Earth Sciences, University of Ottawa.
* Paul Copper, Laurentian University (Emeritus).
* Susan Crockford, University of Victoria.
* Christopher Essex, University of Western Ontario.
* Neil Hutton, past president, Canadian Society of Petroleum Geologists.
* Wayne Goodfellow, University of Ottawa.
* David Nowell, former chairman, NATO Meteorology Canada.
* Peter Salonius, Canadian Forest Service.
* Ross McKitrick, University of Guelph.”
http://www.cbc.ca/technology/story/2009/03/30/tech-090330-cato-climate-change.html
http://www.smalldeadanimals.com/archives/011105.html
Ian W,
It is quite possible to prevent a runaway in a system with net positive feedbacks, since it can be modelled as a converging power series.
Ian W (05:27:50) :
You are absolutely right. For a kiln or an oven to work properly you need insolation, our planet´s insolation it is not the atmosphere but sea water.
In this “post modern” theory it seems that you can keep it warm just with the atmosphere inside the kiln!! It seems somebody is postulating an infinite atmosphere!, like having infinite covers on a bed!
Ivan (05:49:40) :
“But, what we are really interested in is overall net feedback (SW plus LW), not just LW. I believed it is also negative and Lindzen says so, but looking at the graphs he presented show that SW feedback is stronlgy positive as well as overall feedback which is also on positive side (3rd panel). Is there anything I don’t understand correctly?”
Ivan, perhaps the SW increase is cause by increased cloud cover. Again reducing the effect of greenhouse gases and lowering temperature.
Thank you , Dr. Lindzen. I have been following your work for over a decade. You have suffered the slings and barbs of those who disagree. You should be revered for your courage alone, never mind the incredibly sound science. I am well aware of the mud that has been (is being) thrown at those who question the science of a Co2 driven climate. Now that you have thoroughly destroyed the Co2 theory, what are your thoughts on what is actually driving our climate? Dr. Svalgaard, who posts here says that it isn’t the sun ( oversimplified for expedition). I would certainly like to hear your theories. Any possibility? Thank you in advance, …………… David Ball
If the climate sensitivity is only around 0.3 degrees, how do we get ice ages?
Comparing temperatures during the last glacial maximum to today yields a climate sensitivity of about 3 degrees +/- a degree or so (basically the same as the models get).
If the climate sensitivity is only 0.3 degrees, that implies that there is some HUGE completely unidentified forcing responsible for taking us into and out of ice ages. That could be, but it seems unlikely to me.
Is there a way to link directly to this paper or to get a pdf?
“Eloquence is logic on fire.”
To believe AGW, you must believe that 380 PPM CO2 becomes an atmosphere-covering sheet of one-way mirror.
Those shoes just ain’t a pair – the right one is shiny and pointier, the left one is rounder and dull. I suggest the owner gets his eyes tested before he drives again.
That looks like a really old car too. Who knows. Though I haven’t driven an automatic (except for rentals) in over 20 years. I suspect Europeans drive automatics as much as Americans or anyone else. 😉
I was thinking he’d need to get his brakes replaced quite often. And adding a lot of particulate pollution with those quickly-wearing brakes…
anna v (23:08:24) :
“Would you say that the negative feedback shown by the data here is the beginning of an ice age? :). ”
My personal opinion is that most of the observed warming is an illusion (not real and simply due to measurement error). The temperature changes we are dealing with here are smaller than the measurement error.
So unfortunately I think the negative feedback is also probably an illusion. changes are so small relative to noise that this allows everyone to see what they want to see.
I believe we always have positive feedback, BUT we have reached saturation, which can look like negative feedback.
I would invite people to take a close look at the shape of temperature changes coming out of an ice age. Look at the slope. If negative feedback was responsible for ending ice ages the transition from warming to stable temperatures should occur gradually. Instead, temperature increases steadily at basically a constant rate and then sudden becomes a flat top. That is ‘clipping’, i.e. hitting a hard limit.
Another consideration is that if we switched from positive to negative feedback coming out of an ice age we should see this as ‘overshoot’ and oscillations. There is a fairly large delay in negative feedback mechanism. A delay should cause overshoot and oscillation behaviour to be observed, not a sudden clipping, that we actually see — that has to be because of saturation. We never stop having positive feedback, however the system hits the maximum value … saturation, a hard limit. At least that is my theory 😉
Someone above said what I’ve always found amusingly paradoxical about the Gaia hypothesis-namely that it sounds like it speaks of negative feedbacks! Well, the key here is that in order to get into Lovelock’s mind set, you must see humans as inherently separate from nature-negative feedbacks apply to nature, and if we aren’t a part of nature, negative feedbacks can’t protect nature from us. Ridiculous, I know, but Lovelock’s idea makes no sense.
As for the Paleocene-Eocene Thermal Max, mention above, there is a brief discussion here, featuring me:
http://www.globalwarmingskeptics.info/phpbb3/viewtopic.php?f=5&t=343
Very nice argument and clearly presented, thank you Dr. Lindzen. However, it seems to me there is a basic flaw: it is assumed that the LW emission is a function of temperature, only – including a feed-back, of course -but this is not necessarily the case. The cloud cover can change for many reasons, natural variability, cosmic ray intensity etc, and clouds provide an important part of the greenhouse effect. So the LW radiation does not necessarily respond just to the temperature change. In fact, the decrease in cloud cover that gives increased SW energy input (reduced albedo) will also increase the LW output.
Instead, this dramatic change of cloud cover over a short period (10 y) demonstrates that clouds are not a passive system, responding in a well defined way to gradual warming, but a complex dynamic system with other driving forces. And the associated climate forcing is very large, dwarfing at least on this time scale the small effect of increased CO2 concentration.
And… Didn’t sensible people already have the suspicion this was true all along anyway? If the “hysterical green house effect”, (as I call it ;), was actually true then there would be an extreme likelihood that a ‘run-away’ climate occurred during earth’s long geologic past, (along with something else major happening to ‘reset’ us back from a Venus-like condition). There is no such indication that anything like that ever happened.
I’ve always been impressed by the data offered by Christopher Scotese
http://www.scotese.com/images/globaltemp.jpg which appears to indicate a natural ceiling to global temperature, (~23C), which is exactly what one would expect from a strong negative feedback. Thank you Dr. Lindzen for scientifically confirming that nature usually makes sense.
It seems “Nature” prefers balance and if feedbacks were positive things would have spun out of control a long time before we came along. As is my nature, I’m being simplistic, but hopefully not simple. =:o
Ooops, I wasn’t piggybacking on Ian Schumacher’s post BTW. What he calls ‘saturation’ could be described as merely a non-linear negative feedback, (like a zener diode in the feedback loop kinda thingy).
Oh dear. Professor Lindzen is being just a little disingenous. He gives us the graphic from Wielicki and Wong, et al, 2002 without mentioning that this paper was the subject of a comment pointing out an alternative interpretation of the disagreements shown between observations and models is that the analyses of the observations may be flawed. and also Another contributing factor to a flawed analysis could be the way the data were processed.
Flawed observations and data analysis. A favourite theme of this very site!
Nor does Prof Lindzen share with us that in 2005 the authors issued a correction to their 2002 paper in which they stated that …
The effects of the altitude correction are to modify the original reported decadal changes in tropical mean (20N to 20S) longwave (LW), shortwave (SW), and net radiation between the 1980s and the 1990s from 3.1/-2.4/-0.7 to 1.6/-3.0/1.4 Wm-2 respectively
That is, the troublesome trend in LW radiation depicted in the graphic was later found to be a near-100% overestimate. As a practicing climate scientist Lindzen must be aware of this, I wonder why he does not mention it in the article, and what effect the correction had on his conclusion of a remarkably low value for climate sensitivity?
>>>Mike Guerin (23:29:36) :
Is it just me? Am I that smart and everyone else that stupid. Isn’t it obvious that for life to exist on earth there must be a strong negative feedback effect in place. Without strong negative feedback does anyone sane really think that the climate on earth would remain stable enough long enough for life to evolve and prosper?<<<
Yes, yes, yes. This has been my thought all along.
If the system was as unstable as their models suggest, then catastrophic cycles would have been triggered too often in the past.
Has anyone asked the modelers what events could eventually reverse a catastrophic warming cycle? Or do they just assume that it’s perpetually irreversible?
Clarification on the following points would be appreciated.
1. Was the following answered
John F. Hultquist (21:30:22)
It isn’t immediately clear why
“Given the model climate sensitivities, this ‘blanketing’ should typically reduce the emissions by a factor of about 2 or 3 from what one would see in the absence of feedbacks
2. “if one simply doubles the amount of CO2 in the atmosphere, the temperature increase is about 1°C”, and “Climate sensitivity is on the order of 0.3°C”, I then asume the result of doubling CO2 is +0.7°C.
3. Reference the Radiation Anomalies Chart between 1991 and 1992: LW (Red) peaks at approximately -2.5, SW (Blue) peaks at approx +9, NET (Green) peaks at approximately -9. Since (-2.5+9≠ -9), what is NET and does it have any significance in this context?
Roger Knights (05:29:30):
>>>>>But it hasn’t been peer-reviewed, nyah, nyah!<<<<<
Sorry: But,
you have an electric car.
feedback on electric car, nyah,nyah.
Evan: good winds…. and WW II ?????
There is no place for a big or a little or limited greenhouse effect. There is none.
INFRARED IS NOT HEAT RADIATION!!!!
I’m not picking on anyone; certainly not Prof. Lindzen. I greatly appreciate him putting this essay out there to help clarify the debate, and really don’t want to antagonize anyone. However, one quick way to push my (possibly over-sensitive) buttons is to call infrared radiation “heat radiation”. So much so, in fact, that I haven’t even read the whole essay yet. If I seem overly critical of anyone in the rest of this screed, please go back and re-read the first sentence of this paragraph.
Infrared radiation isn’t heat–it’s light. More specifically, it’s electromagnetic radiation that’s just outside the narrow spectrum (visible light) our eyes can respond to.
The reason I think it’s important to keep the two concepts separate is that calling IR heat encourages misconceptions like “carbon dioxide acts as insulation”, or that there can be a mysterious heat sink that is keeping the earth from warming even as our carbon dioxide is trying to warm it. Heat energy is the measure of the kinetic energy of molecules within a body, and IR is electromagnetic radiation, and they are quite different. However, each can cause the other, and therein lies the seed of confusion.
We equate IR with heat for two main reasons. First, elevated temperature is how we normally experience IR. We can’t see IR, but if you put your hand near an electric heating element, the IR radiation is readily absorbed by your hand. At that point, it’s converted to heat, and elevates the temperature of your skin. So you experience the IR as heat.
The second reason we equate the two is IR imaging. Objects near the temperature of the earth (our bodies, rocks, trees, ice, and such) emit IR according to the relationships discovered by Planck, Stefan-Boltzmann, and a whole host of other geniuses I can’t name off the top of my head just now. We can image this IR radiation, and show warmer objects brighter than cooler objects. It’s a convenient shorthand to think of this as thermal imaging, but it’s really not.
One reason this is important is that it makes clear that under the anthropogenic carbon dioxide hypothesis of global warming, the SOURCE of the excess heat is the atmosphere itself. The earth’s surface loses heat by radiating EM energy in the IR wavelength range; the atmosphere absorbs part of this EM through the mechanism of the “greenhouse effect”; that absorption indirectly increases the kinetic energy of the molecules of the atmosphere; and at that moment (and not before) heat is added to the atmosphere, and it’s temp goes up a smidgen.
Looked at from this perspective, it becomes clear that the mysterious “hidden heat sink” that some have postulated to explain why the global temperature is leveling off is particularly silly. If the atmosphere is producing all the extra heat that it must under the hypothesis, it is being transferred to something else as fast or faster than it is being produced. Not only must the heat sink proponents produce evidence of such a sink, they must find a mechanism for transferring all this excess heat from the atmosphere to that sink. That’s a steep hill to climb.
Very very interesting! This article will translate in italian and publish in my site soon…
meanwhille an interestig work with an important grafic by my blog translated by google-translate, so excuse me for english, Simon
http://209.85.129.132/translate_c?hl=it&sl=it&tl=en&u=http://daltonsminima.wordpress.com/2009/03/29/leccezionale-minimo-solare-gia-somiglia-tanto-ai-superminimi-del-passato/&prev=hp&usg=ALkJrhjPC_Q6iSNYz7m_1mc70dTycmHe8A
Degrees kelvin? Oh dear. I still cringe at the memory (decades later) of the bawling out I received when I wrote e.g 255oK. It’s just kelvin – 255K.
It’s nice to see Prof Lindzen’s paper and see the data and model comparisons.
I do have some concerns; and perhaps those concerns relate more to the audience to which Dr Lindzen addressed this paper. He does start out with a heading “Simplified Greenhouse Theory.”
So perhaps available space constrained the amount of detail he includes.
A first concern would be the two terms “long wave” and “short wave”; which would mean different things to a Radio “Ham” I am sure. They don’t mean anything precise to me; so I am going to make a leap of faith and presume, that by “shortwave”, Dr Lindzen means radiation corresponding to the roughly 6000K solar spectrum; and that by “long wave” he means thermal infra-red radiation corresponding to the earth source at 255K (his number) or some other number like 288K corresponding roughly to the alleged mean earth surface or lower troposphere temperature.
If these are not correct assumptions perhaps Dr Lindzen might clarify.
I’m somewhat concerned about lumping the two together in a “net” result; because the detail physics is quite different for those two spectral regions.
I should state here that I am adamantly in total agreement with the final conclusion that Prof Lindzen states; that the current earth climate system is totally regulated by strongly overriding negative feedbacl; a “tipping point” thermal runaway is not possible with the current orbital parameters of the sun/earth system, and the solar constant.
As a physicist (not a meteorologist I look at the problme perhaps a bit differently from Dr Lindzen.
His use of the word “blanketing” is I think quite instructive, because anyone can understand how blankets slow the rate of energy loss from sleeping humans and keep us warmer than we would otherwise be. In the climate case, the delay in exit of the thermal (LW) radiation can be seen as creating a blanket warming, if for no other reason, than the simple fat that during that delay time, the sun keeps on pouring in extra solar spectrum radiation, which will warm things up.
I view the earth’s surface and lower atmosphere warming in a very simple fashion. Two sources of radiation try to heat the surface. The first and most powerful is the solar spectrum radiation from the sun. Most of it propagates some considerable depth in the oceans, to cause local water heating. Some of it is absorbed in the upper atmosphere directly and never reaches the ground; at least as solar spectrum radiation. The other main warming component is the long wave thermal IR emission from the atmosphere itself. This of course is a re-emission of energy which got them from somewhere else, either as direct solar heating, or from surface emitted longwave IR, which is usually thought of as the green house component.
The earth’s surface; particularly the ocean treats the short and long components quite differently; and here my view might not agree with Prof Lindzen’s. As I see it, the long wave returning from the atmosphere is totally absorbed in the top 10 microns or so of the ocean surface or any water on land as well. That must result in very localised warming of the water surface, and lead to rather prompt evaporation of water vapor into the atmosphere. And that isee as a huge energy pump in the form of latent heat of evaportation around 545 cal/gm, which gets carried aloft by the water vapor in convective currents and eventually lost to space from the upper atmosphere. Bottom line is I don’t see any large fraction of that returned long wave energy from the atmosphere being propagated into ocean depths and “Stored” in the ocean. And I also see it as the prime source of the water vapor feedback that ultimately leads to precipitation and the obligatory extra clouds that come with precipitation; and that I see as the direct source of Dr Lindzen’s negative feedback; and although the details may be more complex, it seems to me that the mechanism isirrefutable; specially in light of the paper of Wentz et al in SCIENCE July 7 2007; “How Much more Rain will Global Warming bring?”
As to the fate of the solar spectrum energy propagated into the ocean many metres; the depth of propagation is like the solar spectrum turned upside down; the highest intensity spectral components in the blue green region going deepest, and the red and violet ends being attenuated at shallower depths.
From there I don’t see any powerful mechanisms form moving this energy significantly deeper, to store it in the deep oceans. There will of coursae be conduction in all directions; but since ordinary sea water always has a positive temperature coefficient of expansion down to its freezing temperature, there must be upward convection currents established by the solar energy warming, so the deposited solar energy must in my view be inexorably transported back towards the surface, and since convection almost always trumps conduction; I don’t see a deep ocean energy storage mechanism, other thqan what ocean circulations might be set up by the local georgraphy.
Anyhow, I’m skeptical that there is much of a downward flow of energy into the ocean; I think it is largely returned to the surface over time,a nd ultimately lost to the atmosphere or space, by surface radiation (nearly black body) and conduction or evaporation.
As to the component of the long and short wave radiations captured by the atmosphere, it is clear from absorption spectroscopy that water vapor is a significant absorber of solar spectrum radiation and CO2 is not, and as for the long wave, water vapor once again absorbs over a much larger spectral range than CO2, so a doubling of CO2 is really just a drop in the bucket of increased green house absorption, since the atmosphere doesn’t really care which molecular spoecies captured the IR photon and conveyed the energy to ordinary atmospheric gases in collisions.
So to me the concept of “climate sensitivity” is simply a red herring. Any immediate surface warming due to a CO2 increase, sets in motion the evaporation/cloud formation/precipitation feedback which is always strongly negative.
As I have said many times; nobody ever observed it to warm up when a cloud passes in front of the sun; it always cools in the shadow zone; and the fact that last night it remained a little warmer overnight because of some high cloud cover, is irrelevent. It still cooled down after sunset; and in any case, that was last night’s weather; not climate.
I would hope that Prof Lindzen would take advantage of sites like WUWT to educate more of us in this arcane subject matter.
George
Another Mike D (22:39:57) : I think that the main temperature difference between Venus and us isn’t the difference in energy coming from the sun, it’s the surface pressure. I live in Chinook country on the Eastern slope of the rockies I can vouch for a 30 degree centigrade temperature change over about 6 hours when the chinook kicks in (quick version: air cooled over the mountains follows down the mountain slopes, pushes up against valley air and forces compression.
I think it is heating because of the compression — IOW: the change in pressure. Look up adiabatic process.
John Philip,
How odd that Dr. Lindzen failed to cite every critique of his references.
Unlike Hansen and Schmidt who always present a balanced view and diligently refer to every criticism of their work and citations.
Re: alexjc38 (06:08:29) :
“How does the Eocene warming episode of 55 million years ago (PETM) fit into this? I often see it mentioned as an example of positive feedback at work.”
Not sure what other have written here on the Eocene, but there was more than just atmosphere/ocean effects at work during the Eocene.
What we know about the Eocene is this
1) Just before the Eocene, the Indian plate drifted North and ran smack into Asia forming the early Himalyas.
2) The Eocene then started with one of the most extreme rises in temperature known in the geologic record and is correlated with a sharp extinction event which removed a lot of the prior Paleocene fuana. What caused the warming? Unclear – the forming of the Himalyas would have most certainly generated a massive change in the global circulation pattern. CO2 outgassing from this event could have reinforced warming, but a dramatic change in the surface topography of the Earth has to be player!
3) The temperature gradient between polar regions and equatorial regions during the Eocene was half what it is today with the polar regions much warmer – temperate forests extended right to the poles during the Eocene. Eocene Palm Trees have been found in Alaska and Swamp Cypress on Elsemere island in the Artic for example. The recent finding of a fossil snake the size of a school bus in Columbia also extends from this period.
4) Other factors at play are that a) at the beginning of the Eocene, Australia and Antartica were still a connected super continent (warm equatorial currents able to mix with colder Antartic waters easier than they can today), and b) Europe, Greenland and North America were still part of one supercontinent at the start of the period.
5) By late in the Eocene, both these supercontinents had split and the Mediterranean had formed.
6) There was then another extinction event late in the Eocene – which is correlated with 2 major impact events – one over Siberia and the other in the Chesapeake Bay . This extinction is known as the Grande Coupure or “Great Break” which is also associated with a major turnover in fauna and the arrival of the first Europeans from Asia.
The bottom line is – I don’t think you can attribute changes in Climate during the Eocene (particularly early in the period) to the same feedbacks in the atmosphere/ocean that we are talking about here. There were dramatic geologic changes during this period.
John Philip (07:37:24) :
I can’t tell from the graph whether Lindzen used the old figures or the revised ones. He does reference 4 other papers on the same data so I’m inclined to think he’s got current figures.
But how can you tell?
“”” Ian Schumacher (06:52:07) :
anna v (23:08:24) :
“Would you say that the negative feedback shown by the data here is the beginning of an ice age? :). ”
My personal opinion is that most of the observed warming is an illusion (not real and simply due to measurement error). The temperature changes we are dealing with here are smaller than the measurement error. “””
Ian, where did you get the idea that negative feedback ends ice ages. I don’t think ice ages are something that happens from a slight imbalance in the climate. Major changes of orbit parameters and the like or solar changes create and eventually end ice ages; not some minor weather shift.
As to the “switching” from positive to negative feedback; it is quite elementary.
Water vapor which is far and away the only greenhouse gas of any significance at all, creates positive feedback warming by absorbing lots of earth emitted long wave IR. It also has some negative feedback component since it also absorbs incoming solar radiation, which reduces the ground level insolation (and warms the upper atmosphere; which then radiates to space). But water vapor in the atmosphere eventually leads to both liquid and solid water in the form of clouds; no other GHG does that; and clouds reflect incoming solar radiation back into space (albedo effect),a nd then they block further solar radiation from reaching the ground; thereby cooling the surface. The shadow zone formed by a cloud is ALWAYS cooler than outside the shadow zone.
So water exhibits both positive and negative feedback depending on the phases present. At any time, total global cloud cover is around 50% If it warms up (for any reason) you get more evaporation from the ocean, which must be balanced eventually by more precipitation,a nd that means more clouds blocking more sunlight so it gets cooler.
If it gets too cool, you get more precipitation, leading to less cloud cover, so more sunlight reaches the ground, and it warms bacl up.
How difficult is that to understand. So long as the earth has its oceans we could neither raise nor lower the temperature by any significant amount; even if we wanted to.
George
Ivan (05:49:40) :
But, what we are really interested in is overall net feedback (SW plus LW), not just LW. I believed it is also negative and Lindzen says so, but looking at the graphs he presented show that SW feedback is stronlgy positive as well as overall feedback which is also on positive side (3rd panel). Is there anything I don’t understand correctly?
During the ‘inadvertent experiment’ described by Lindzen he shows a sharp increase in LW associated with a sharp rise in temperature but no corresponding increase in SW (so no increase in tropical clouds).
Where the models apparently go wrong is that they produce more clouds in the tropics in response to warming whereas the data suggests that they should not.
Apart from the obvious point that if the climate was dominated by strong negative feedback how did the sharp rise in temperature occur, the analysis is flawed in another way.
From the ERBE website:
“In general, the absorbed solar radiation exceeds the outgoing longwave radiation in the tropical and subtropical regions, resulting in a net radiative heating of the planet, while in the middle to polar latitudes there is a net cooling. This equator-to-pole difference, or gradient, in radiative heating is the primary mechanism that drives the atmospheric and oceanic circulations. On an annual and long-term basis in which no energy storage and no change in the global mean temperature occurs, this radiative imbalance between the tropics and polar regions must be balanced by meridional heat transport by the atmosphere and oceans.”
So Lindzen is demolishing a strawman, a system where LW losses from the tropics are balanced by SW input to the tropics. However, the input in the tropics is balanced by LW from the whole planet due to the aforementioned meridional flows. So in order to do this type of analysis he needs the data from the whole planet. So nice try but no cigar!
Robert Bateman (03:36:25) :
If I am getting all of this correct: The satellites measured the shortwave coming from the Sun, and the longwave being lost by the Earth, and found equilibrium.
No, the satellites are measuring both SW and LW from the earth. The sun’s radiation is relatively constant. The relation between temperature, outgoing LW and outgoing SW radiation is basis of this thread.
Re: Eocene Warming
“CO2 outgassing from this event could have reinforced warming…”
To clarify- the standard theory is that there was first a massive outgassing of circa 1400-2800 Giga tons of methane from oceanic clathrates during this period (likely due to the collision and subuction of the Indian Plate under Asia) which then led to massive carbonate dissolution in marine sediments which then released CO2.
Again, very different to what have seen over the past several 100 years…
Graeme Rodaughan (22:45:14) :
“It’s the Evidence guys….”
Thank you for giving Dr. Lindzen’s work such a clear, honest perspective. There are indeed much bigger issues to address than the now thoroughly falsified AGW theory.
Exactly the same thought came to my mind and I was going to say so but checked the comments to see if anyone else had noticed it.
This is EXACTLY what Dr. Spencer has been saying … the observations do not match the models. He made the case here back in December and I believe he is close to submission of a new paper on the subject.
Ian Schumacher (06:52:07) :
Another consideration is that if we switched from positive to negative feedback coming out of an ice age we should see this as ‘overshoot’ and oscillations.
I do not know about overshoot, but certainly at the flat top there are oscillations:
http://en.wikipedia.org/wiki/File:Vostok-ice-core-petit.png
particularly in the holocene.
http://upload.wikimedia.org/wikipedia/commons/c/ca/Holocene_Temperature_Variations.png
I hope by oscillations you use the generic term and not a “harmonic oscillator” expectation.
So of course there are negative feedbacks. The most important one iw albedo changes. Try the toy model :http://junkscience.com/Greenhouse/Earth_temp.html
by changing the albedo.
Ian: The latest on NPR was an interview with this lady who stated that there really isn’t anything they can do about runaway AGW, but that they will do as much as they can. As much as they can to throw whatever they can under the Bus to slow it down. This is the cry I am hearing now. It’s too late, but they will go down fighting.
The unstable node distrubed, massive boulder plunges down slope to sleepy village below.
anna v (08:41:15) :
So of course there are negative feedbacks. The most important one iw albedo changes.
In the context of ice ages, albedo is mainly a function of the extent of ice cover, and it is a POSITIVE feedback, not negative.
Warming results in less ice cover; less ice cover means lower albedo; lower albedo means more sunlight is absorbed, which translates into more warming.
Good article, but it’s too bad that Lindzen falls for the “blanket” baloney. If that idea is true, it would have to be hotter in Miami on a clear summer day than in Phoenix. The reverse is true.
anna v (08:41:15) :
“So of course there are negative feedbacks. The most important one iw albedo changes.”
I think albedo changes are positive feedback (I’m thinking of melting ice that is). Melting ice is a positive feedback change, the effect of which gets smaller as the ice shrinks to only be at the poles. This ‘should’ show up as temperature changes slowing down as the earth comes out of a ice age … but I don’t see it.
Going from these types of positive feedbacks to negative feedbacks ‘should’ result in a curved top. Delayed negative feedback ‘should’ result in overshoot and oscillations (on the flat part).
Is it possible that positive feedback switches to negative feedback so suddenly to accomplish the discontinous temperature change? Sure, its ‘possible’, but it is certainly not the simplest theory. Why not consider the much simpler theory of reaching the a physical limit. That seems to match well with the data and doesn’t require any ‘hand waving’ at complexities.
From vg quoting the Examiner quoting Hansen:
“…the mistaken impression that concern about global warming is based on climate models, which in reality play little role in our understanding…”
Actually, I think it’s possible Dr. Hansen actually believes this.
To Ed Fix:
according to your first sentence, there is NO radiative heat transfer mechanism. And there is NO infrared or near infrared imaging technique or terminology.
I don’t know who need to go back to graduate school to study radiative transfer course, Ed Fix or everyone else.
LOL
Richard Heg (23:48:31) :
“One thing that puzzles me in the environmental movement with regard to feedback is Gaia theory as proposed by James Lovelock which as defined in wiki http://en.wikipedia.org/wiki/Gaia_theory says:
“The Gaia hypothesis is an ecological hypothesis proposing that the biosphere and the physical components of the Earth (atmosphere, cryosphere, hydrosphere and lithosphere) are closely integrated to form a complex interacting system that maintains the climatic and biogeochemical conditions on Earth in a preferred homeostasis.”
This sounds quite elegant to me, that the biological and geological activity produce a feedback system which unlike our neighbors Mars and Venus has kept the earth in a state which allows life to exist. It goes on to say:
“Some relatively simple homeostatic mechanisms are generally accepted. For example, when atmospheric carbon dioxide levels rise, the biomass of photosynthetic organisms increases and thus removes more carbon dioxide from the atmosphere, but the extent to which these mechanisms stabilize and modify the Earth’s overall climate are not yet known.”
So my reading of Gaia theory says nothing to worry about the earth is full of feedbacks which keep thing relativelyly stable. Problem solved, now lets have a nice cup of tea.
However James Lovelock seems to have a different vision, he seems to see humans as a cancer. Here is a quote from a recent interview:
“Because of this (AGW), the cull during this century is going to be huge, up to 90 per cent. The number of people remaining at the end of the century will probably be a billion or less.”
http://www.newscientist.com/article/mg20126921.500-one-last-chance-to-save-mankind.html
I dont understand how i can look at a theory and come to the exact opposite conclusions of the person who proposed it”.
Richard,
It’s because you look at things from a scientific point of view.
The other party looks at it from a political ( eco fascist ) view.
http://green-agenda.com and Chapter 21 http://www.un.org/esa/sustdev/documents/agenda21/index.htm
An accelerator pedal has negative feedback, because pressing it causes the car and pedal to move away from your foot and decreases the pressure on the pedal. A brake pedal has positive feedback, because pressing it causes the car and pedal to slow more quickly than your foot so the foot tends to push on it harder.
Ron de Haan: Some people think that feedbacks keep the Earth in some ideal state of balance, and humans have upset the balance. Others think that feedbacks tend to encourage the Earth toward being habitable but the system is both chaotic and open to outside influences so there is no guaranteed balance nor comfortable range.
Unresolved issues: The Little Ice Age affected many regions recently. Were those temperatures at the proper balance point? Which of the recent temperatures is the proper temperature for the Earth? Is the proper temperature reached during a glacial event?
There is an excellent article in Wired (March 3, 2009), “Recipe for Disaster: The Formula That Killed Wall Street.”
http://www.wired.com/techbiz/it/magazine/17-03/wp_quant?currentPage=1
This article analyzes how David X Li’s work caused the worst economic meltdown since the Great Depression. Its opening paragraphs set the stage:
“A year ago, it was hardly unthinkable that a math wizard like David X. Li might someday earn a Nobel Prize. After all, financial economists—even Wall Street quants—have received the Nobel in economics before, and Li’s work on measuring risk has had more impact, more quickly, than previous Nobel Prize-winning contributions to the field. Today, though, as dazed bankers, politicians, regulators, and investors survey the wreckage of the biggest financial meltdown since the Great Depression, Li is probably thankful he still has a job in finance at all. Not that his achievement should be dismissed. He took a notoriously tough nut—determining correlation, or how seemingly disparate events are related—and cracked it wide open with a simple and elegant mathematical formula, one that would become ubiquitous in finance worldwide.”
“For five years, Li’s formula, known as a Gaussian copula function, looked like an unambiguously positive breakthrough, a piece of financial technology that allowed hugely complex risks to be modeled with more ease and accuracy than ever before. With his brilliant spark of mathematical legerdemain, Li made it possible for traders to sell vast quantities of new securities, expanding financial markets to unimaginable levels.”
“His method was adopted by everybody from bond investors and Wall Street banks to ratings agencies and regulators. And it became so deeply entrenched—and was making people so much money—that warnings about its limitations were largely ignored.”
“Then the model fell apart. Cracks started appearing early on, when financial markets began behaving in ways that users of Li’s formula hadn’t expected. The cracks became full-fledged canyons in 2008—when ruptures in the financial system’s foundation swallowed up trillions of dollars and put the survival of the global banking system in serious peril.”
There are significant similarities between Li’s work and the GCMs that the AGWers, media and policy makers ignore at their peril. If they get their, trillions of dollars will be squandered and our economy destroyed.
The closing paragraphs from this article put all modelers, especially climate modelers, and their work in perspective:
“Li has been notably absent from the current debate over the causes of the crash. In fact, he is no longer even in the US. Last year, he moved to Beijing to head up the risk-management department of China International Capital Corporation. In a recent conversation, he seemed reluctant to discuss his paper and said he couldn’t talk without permission from the PR department. In response to a subsequent request, CICC’s press office sent an email saying that Li was no longer doing the kind of work he did in his previous job and, therefore, would not be speaking to the media.”
“In the world of finance, too many quants see only the numbers before them and forget about the concrete reality the figures are supposed to represent. They think they can model just a few years’ worth of data and come up with probabilities for things that may happen only once every 10,000 years. Then people invest on the basis of those probabilities, without stopping to wonder whether the numbers make any sense at all.”
Chris V. (09:22:48) :
Ian Schumacher (09:38:23) :
Seems to me both of you should play with the toy modelthat shows how sensitive the earth temperature is to albedo, both positive and negative.
Has none of you looked up and seen clouds? Or do you think all that ice during ice ages came by magic?
In my opinion it is the large sun cycles that explain the ice ages, the feedback mechanisms are all those oscillations, both on the inclines and on the flat tops.
Just to say thanks realitycheck for answering my question re the Eocene!
I am not optimistic any fact is capable of pushing aside an endorsed government/ NGO paradigm. A greater understanding is required of the first model used to declare a crisis during the “Acid Rain Debate”-called the Magic Model (perhaps because it could magically produce whatever result one wanted). The scientific facts regarding soil acidifcation clearly showed acid rain was not a dominant factor in soil or water acidification however Congress passed the related legislation without having read the report. (EPA refused to release it till after the legislation was passed). The lead researcher, Ed Krug, was smeared by both EPA and the NGOs- and his career destroyed. We have now moved some twenty years forward in time and the predicted recoveries of soil and water pH have not been achieved. EPA/NGOs have given two reasons for this- the first that the impacts of acid rain were so devastating that it will now take a hundred years to see improvements (Acid rain taught to always move the model beyond ones lifetime) The other unbelievably is that global warming is causing increased water acidity. (If you believe that increased global warming causes increased precipitation and increased precipitation in areas of granite geology causes the growth of bog plants which produce organic acids and sequester calcium causing a depression in pH-then yes global warming has replaced acid rain. It is a good example how we manufacture truth in today’s academic papers. It has all been done before- perhaps we need to focus on acid rain as a tool to understand global warming and why nothing prevented the suppression of science.
Recent work in crisis psychology says the first information received controls all beliefs framing a perceived crisis. Future conflicting information is disregarded. Alarmism is a first strike strategy for which we have not found a counter strike solution.
History is an important tool- the National Academies of Science was formed as a tool to isolate and marginalize the advocates of Charles Darwin. Only anti- Darwin scientists would be invited to join- a great overview in the book Reef Madness. (Dr. Lindzen’s comments on the NAS process would not have surprised Darwin’s advocates)
Very informative …
It would be easy to see, that if the positive feedbacks were present in the atmosphere, then at some time in the past millions of years, the earth’s climate would already be pegged at one extreme or the other.
“Recent work in crisis psychology says the first information received controls all beliefs framing a perceived crisis.”
I would say first and last … everything in between being just noise. For example, if something is widely disseminated that turns out to be false but the correction is only narrowly disseminated, the “conventional” wisdom will hold with the original information for a very long time. Newspapers and TV rely on this when they lead with a huge story that turns out to be incorrect and bury the correction on page D-34 or in a blurb on a 3am newscast. Everyone saw/heard the incorrect information, very few saw/heard the correction.
Now if the correct information is given as wide a dissemination at the same times and frequency of repetition as the original was, then it would be as widely held as “true”.
Example, place a front page headline and “breaking news” story on every network that a passenger plane was shot down by a missile. Repeat the story for a couple of days. Then once the story is off the front burner, put out the fact that it was mechanical problems and bury that information in a single sentence in a news broadcast and on a back page of the newspaper and poll people 6 months down the road … they will still believe, by and large, that the plane was shot down. But the media will swear up and down that they reported the “facts”.
Same with “global warming” stories. An arm waiving activist gets the headline and contrary information is buried. But the outlet claims “fairness” and that they “reported” both sides.
“”” Chris V. (09:22:48) :
anna v (08:41:15) :
So of course there are negative feedbacks. The most important one iw albedo changes.
In the context of ice ages, albedo is mainly a function of the extent of ice cover, and it is a POSITIVE feedback, not negative.
Warming results in less ice cover; less ice cover means lower albedo; lower albedo means more sunlight is absorbed, which translates into more warming. “””
Anyone who believes that ice cover is a major part of albedo hasn’t been looking at pictures of the earth recently. Pictures like the famous earth rise from the moon show clearly that the albedo is dominated by clouds; about 505 of the earth’s surface at any one time is covered by clouds. Clouds arise mostly where the atmosphere has plenty of moisure and most of the time that is in the hot tropical areas, rather than the cold polar areas. So tropical clouds are reflecting solar energy away from earth mostly at the places where there is more arriving solar energy; namely in the warmer tropical areas (per square metre).
The earth’s ice cover on the other hand, particularly the “permanent ice” is mostly at the poles; Antarctica and the Arctic. Those areas are only obliquely illuminated by the sun and for only short periods of time, so there is much less solar irradiance where those polar ice sheets are.
Hint to Chris and Ian. See if you can come up with a logical reason why those ice sheets are there at the poles. Why aren’t there large floating ice sheets on the equator ?
In terms of earth’s albedo, ice and snow are bit players.
Ice and snow aren’t as refelctive as some people think either. Freshly fallen snow can be quite reflective at solar spectrum wavelengths, as much as 90% relative to a BaSO4 reference, but that can drop in half after a few days exposure. When snow melts under sunlight, you get optically transmissive windows formed on the surface,w hich can then transmit light a long way into a snow pile, and it gets trapped in there by Total Internal Reflection and other mechanisms; so after a few days it might not be any more reflective than trees or grass. But besides all that there’s just not a lot of snow and ice in the same places that have a lot of solar radiation; I know that sounds weird to some people but it is true. Clouds on the other hand behave exactly opposite from snow; they tend to form in places with a lot of incident sunlight (with water present).
Besides, when the artic sea ice melts, that opens up a vast amount ox extra water surface which then takes up CO2 from the atmosphere; which is why you get that 18-20 ppm P-P cycle in the arctic, so that reduces the CO2 GH effect, and allows thermal radiation to escape more easily. the exposure of the warmer ocean waters to the atmosphere, when that ice melts also leads to enhanced radiation from that surface compared to the ice it replaces.
So don’t bet on the melting arctic ocen to have a great global warming effect.
No I’m not suggesting it cools instead; just that it isn’t the big warmer some people think.
George
There actually seems to be hard wiring in the brain for believing the first alarmist information. It frames all future information. Availability is certainly involved in the cognitive bias produced by media – but does not seem to explain everything. First strike is important.
The larger question for me is how to make facts mean something- Acid Rain used the same tactics of reasoned scientifc debate as is being followed on this site and failed. In fact all one needed to do to open debate concerning the acid rain paradigm was to pour some distilled water through peat moss and measure the pH. Acid rain alarmism could have been tested in a high school chemistry class and yet was unable to convince the EPA, NGOs, media or the Public. Global warming is far more complex an issue. The facts presented about AGW on this site are correct, however, acid rain teaches the strategy is failed. We need a new strategy to present the facts.
“”” Ed Fix (07:51:37) :
INFRARED IS NOT HEAT RADIATION!!!! “””
Ed, I’m in agreement with you; but it could be nothing more that Prof Lindzen being a bit less than pedantic with his terminology; which is always a problem when dealing with possibly lay audiences. that’s partly why I flagged the “long wave” / “short wave” terms. I doubt that Dr Lindzen doesn’t know the difference.
The way I like to put your objection is by saying “HEAT IS NOT A NOUN !”
And I was certainly not the first to make that observation. One way to put it would be to say that “heating” is the process by which other forms of energy, are converted into the purely mechanical Kinetic energy of atomic or molecular agitations. In that sense “heat” (not a noun) cannot propagate through a vaccuum, although radiation certainly can.
Inevitably when scientists try to communicate with lay persons; the accurate scientific terms may become very stodgy and perhaps not helpful, so you either have to laboriously explain those terms, or else try to put it in a more “user friendly” way (and words) and thereby lies confusion.
I can’t hold that against Lindzen; I’m Happy he made the effort to be communicative.
George
J.Hansford (02:06:52) :
“Is our democracy strong enough to override the massive political impetus that AGW has built up….? After all, there is a whole green Socialist agenda relying on those carbon taxes and emission trading schemes…. and the careers of those that have attached themselves to a lie. Whole industries are gearing up to go green.”
It’s already happening. The foundations for cap and trade were in legislation last year. Bits and pieces of the green agenda were in the stimulus bill. A bill was submitted to the house yesterday to create a ‘Green Bank’–kinda lika Fanny and Freddy but for the green agenda ostensibly to help finance the grid to make it smart and to hook up all those G.E. wind turbines and solar panels.
The GM bailout is using the techniques of bankruptcy to let the government decide which plants to keep open and which to close. I doubt we’ll be surprised by the demise of the Hummer and probably SUVs as well. The incentives to purchase autos give you more of a break the greener the car you purchase.
The 2 million acres set aside as protected land also protects the waterways running through them and much of this new land is in states such as West Virginia—goodbye coal mining–and a couple out West–goodbye oil shales.
Obama has already cut funding for Yucca mountain research–goodbye nuclear power. He’s already reinstated the offshore drilling ban.
There’s more. The above is just off the top of my head. Obama is smart–he wouldn’t do this in the open and all at once because he knows there would be a huge backlash. The greenies, however, know exactly what he’s been up to.
This is the face of ‘energy independence’. Not independence from foreign oil, but independence from carbon.
And what is making it all worse is the war on capitalism because of this financial crisis. The forces of the green movement, the anti-capitalists, and the warmers have all converged. And America is left dependent on a dozen blue dog Democrats in the Senate who have no clue as to what just hit them.
re feedbacks
As I understand it before each glaciation started the Arctic may have been ice free (and sea levels were higher than today). The warmists always warn us that an ice free Arctic will mean less albedo and further warming due to this positive feedback. I think the opposite occurs–negative feedback. Less ice means more ocean cooling. In fact I think this may have been a causitive factor (or I could be all wet) in the cold cold winter we had after the ‘unprecedented melt off’ of Arctic ice a couple of years ago.
Oh, and if we’re worried about the next glaciation (well, we should be, we just don’t know when) and cannot depend on CO2 to warm us out of falling into it there is another possible solution (besides the ones mentioned by anna up above)…..
we can blow up Panama 🙂
Is it just me? Am I that smart and everyone else that stupid. Isn’t it obvious that for life to exist on earth there must be a strong negative feedback effect in place. Without strong negative feedback does anyone sane really think that the climate on earth would remain stable enough long enough for life to evolve and prosper?
No worries – many people must have concluded much the same, at least I did.
It does not take a rocket scientist to figure out that the atmosphere must somehow be inherently stable. High school calculus comes to mind “minima” and “maxima” – indeed if we happened to be sitting on a highly sensitive and unstable atmospheric maxima then surely things would have gone completely awry 100 years, 1000 years, 10,000 years, 100,000 years, 1,000,000 years, 10,000,000 years, 100,000,000 years, or 1,000,000,000 years ago ! Clearly there are stabilizing phenomenon (negative feedbacks) that we don’t yet fully understand.
I am surprised that any logically minded scientist could accept a model that had positive feedbacks and was therefore inherently unstable. Things that are inherently unstable tend to come crashing down sooner or later – like a coin placed on its edge.
If the logic goes more CO2 => hotter temperature => less clouds => even hotter temperature => even less clouds => even hotter temperature etc. etc. then it clearly makes no sense viz a viz what we observe …even a child can see that.
Onset of Ice Ages:-
Ice Ages are cyclical in the Earth’s recent (last 30m years) past.
Original cause:-
Continental Drift of Antartica over the south pole 40m years ago. Ice pack at first formed over mountainous regions. This caused a negative temperature feedback due to the increased albedo, eventually the entire continent was covered with ice. This permanently reduced the surface temperature of the earth.
Cyclical Ice Ages – Why?
Once the surface temperature is lowered, the variability of the Earth’s orbit around the sun which causes a variation in the balance of solar radiation NH/SH summer/winter leads to summers cold enough to allow snow to remain unmelted and to accumulate.
Prior to the Antarctic moving over the South Pole, this would not happen as the earth’s surface would have been too warm.
The 3 parameters and periodicity is as follows:-
Orbital eccentricity varies between 0 (a perfect circle, sum always 93m miles away) and 0.1 ( min 88m miles max 98m miles) , period 100,000 years.
Axial tilt varies between 22.5 and 24.5 degrees , period 41,000 years.
Precession of the equinox , period 26,000 years. This parameter determines which month the summer solstice occurs, and impacts on the first 2 variables.
To start an Ice Age, the above parameters cause a lowering of solar radiation in the NH in summer. Snow does not melt from the previous winter and a negetive temperature feedback driven by increased albedo sets in. The Ice marches south. Typically all of Canada, the Northern part of USA all of Scandinavia and most of Northern Europe have permanent Ice sheets. Obviously, Greenland and Antartica remain Ice covered.
To end an Ice, the opposite to the above. i.e. increased solar radiation at the in NH summer.
As Ice ages typically last 10 times longer then the inter-glacials, it seems clear that Ice Ages are easier to start then to end.
If the conditons are right, a run of cold winters caused by something like a Maunder minimum solar event could be enough to tip the climate into an Ice Age. This might be less than 100 years from interglacial to Ice Age, though of course this is hard to prove.
Current orbital parameters would sustain an Ice Age, all that is needed is a Maunder minimum to push the climate over.
Something else to ponder, at the moment the Sun has entered a long period of quiet. This is not a Maunder minimum, yet.
Dr. Lindzen is one of the scientists I respect most, however he is being bashed in the media and by certain groups. When you can not debate someones ideas, you attack the person, and that is beginning now to pickup.
pmoffitt (11:24:00) :
. Global warming is far more complex an issue. The facts presented about AGW on this site are correct, however, acid rain teaches the strategy is failed. We need a new strategy to present the facts.
We need a deus ex machina, because the whole AGW thing is into myth and magical thinking.
Fortunately the gods seem to be with us, what with cycle 24 dragging its feet and the PDO etc turning cool, one or two such harsh winters in the EU and US and wet cool summers will do much more than any scientific expostulations could.
One could say that Gaia loves CO2 and does not want to be deprived of it :).
I’m having a problem with this:
“The wavelength of the heat radiation corresponds to the temperature of the earth’s atmosphere at the level from which the radiation is emitted (ca 255oK).”
Is he saying that the Earth emits radiation at 255K? Because that’s just not true. I’m sure I’m just misunderstanding something, and would appreciate someone ‘splaining it to me.
Thanks!
anna v (10:26:51) :
Has none of you looked up and seen clouds? Or do you think all that ice during ice ages came by magic?
No- from milankovich cycle induced changes in ice albedo, plus various positive feedbacks.
If clouds are a negative feedback (as Lindzen implies in the opening post) then the cloud feedback would “resist” the ice ages- not help them along.
George E. Smith (11:07:59) :
“In terms of earth’s albedo, ice and snow are bit players.”
I’m pretty sure that going into and coming out of a ice age, ice and snow are the most important players.
Water vapor creates clouds that act as negative feedback, but also the water vapour itself acts as a greenhouse ‘gas’ so that is positive feedback. The switching from one to the other should show up in temperature data going into and coming out of ice ages as a gradual change in the rate of temperature change. I don’t see that in the temperature data.
tarpon (10:40:59) :
“It would be easy to see, that if the positive feedbacks were present in the atmosphere, then at some time in the past millions of years, the earth’s climate would already be pegged at one extreme or the other.”
Exactly. How do we know that it isn’t pegged to an extreme right now? I think it is. Not sure why that is so implausible to some.
I would suggest that some effort should be given to attacking this issue sideways. Perhaps we can gain clarity with questions-
When was the debate over? (this would actually provide some useful information as to the amount of scientific evidence necessary to close debate- surely we have a right to a date. I’m really surprised noone has asked this question)
Look for what is not there. We are told that we have passed a tipping point and due to the CO2 already in the pipeline we can expect some level of climate disruptions. One would expect therefore to find massive infrastructure projects in the trillion dollar budget passed by Congress to combat rising sea levels, droughts, floods etc. Where are they?-Show the sea wall projects etc. Sometimes questions are as powerful as facts.
Hence the “Gore Effect”!
To Wayne (09:48:00) :
You said: “according to your first sentence, there is NO radiative heat transfer mechanism.”
Actually, my first sentence: “Infrared is not heat radiation” does not equal “there is no radiative heat transfer mechanism”.
To rephrase, electromagnetic energy and heat energy are profoundly different forms of energy. Electromagnetic energy radiates; heat does not. That does not mean there is no radiative heat transfer mechanism–of course there is.
A warm body loses heat by radiating electromagnetic energy in infrared or some other wavelength spectrum. That EM energy MAY be absorbed by another body and cause an increase in heat in that body.
For many purposes, it is convenient to treat IR and heat as equivalent, but ignoring the fundamental physical difference between the two forms of energy can lead to muddy thinking and silly hypotheses like the Invisible Global Heat Sink.
Wayne, I suspected no one would read my whole post and understand it, especially since it was hastily written and mostly off topic. You prove me right. I’m probably a little old to go back to grad school, especially to study freshman physics. And you’re not everyone else.
LOL
George E. Smith (11:25:30) :
You’re right; I was being pedantic. I thoroughly enjoyed Prof. Lindzen’s essay. I certainly have a better understanding of his topic (of which my post was somewhat off-), and I understand why he used the equivalence language.
It just makes me crazy to channel surf through the Discovery Channel, and see a nice, neat, and convincing animation showing “heat” radiating off the surface of the earth, and being trapped by an (exclusively anthropogenic) insulating blanket of carbon dioxide. I much prefer the Discovery Channel’s work with “Dirty Jobs”.
And it really upsets me when scientifically literate folks use the equivalence language to convince themselves of things that can’t possibly be so in the real world.
“Heat is not a noun”. I’ll have to remember that.
This may be a boring question for you here, but what study or science is the foundation of this belief that doubling the CO2 in the atmosphere raises temperature about one degree? The IPCC report is vague about this. Thanks for any pointers you all can give me.
Just this AM I had a conversation with one of the alarmists, nowhere near a scientist or engineer type. More of just a wide eyed arm waver. After he waved his arms around for a while, I injected a single question “How much CO2 is too much” — He answered enthusiastically “none”.
At which I added, ‘do you know what that would mean?’ — Blank stare.
kevin: the 255 K is calculated from the average Top of Atmosphere outward radiation (which equals radiation in), assuming blackbody emissions (T = (Radiation/alpha)^0.25. It is supposedly the temperature the earth’s surface would be without greenhouse gases. But it is a baloney number, because it represents only a planet, like the moon, that has no atmosphere or water. Of course, the Earth has both, so the calculation is complete nonsense. In fact, correct calculations that include the effects of the atmosphere and water would show that the Earth’s average temperature “should” be what it is, about 15 C. The “greenhouse gases” simply help transfer kinetic energy (temperature) to the N2 and O2 that makes up 98% of the atmosphere, through the process of thermalization. Convection makes sure that the greenhouse gases (CO2, HOH, etc.) cannot cause further warming. Indeed, if they did cause some “blanket” warming effect, then it would have to be hotter in your favorite tropical paradise on a clear day than it is in Phoenix in July. But it never is.
Here’s an article that possibly explains the mechanisms: http://www.ilovemycarbondioxide.com/pdf/Rethinking_the_greenhouse_effect.pdf
pmoffitt wrote:
“We need a new strategy to present the facts.”
It would be very helpful, I think, if someone with a good handle on this issue could formulate bettable questions that would be easy for the predictions-betting website Intrade to settle, and challenged alarmists to put their money where their mouth is wrt the various indicators of global warming, such as arctic ice extent, sea level, heating degree days in the US, ocean temperatures, and one or two other matters. (There should be several questions because none of these indicators correlates perfectly with the global temperature, so people will need to spread their bets.)
I described what might be done in detail (using the Dublin-based event-prediction betting site Intrade) about 25% of the way through this thread on this site:
http://www.google.com/url?sa=U&start=2&q=http://wattsupwiththat.com/2009/03/02/poll-and-polar-ice-trends/&ei=bX3SSfmbIZG4sgPsmKjGAw&sig2=dlVs9GDVE1GqULp68toGCg&usg=AFQjCNFAxQsx5StKiAAJ0pksVzbmZVDLrA
2. The feedbacks are responses to temperature – not to CO2 increases per se.
After 2002 the temperatures have been going down supposedly due to decreased activity of the Sun even though CO2-levels have risen. Because the impacts of the feedbacks are functions of the temperature, they must be smaller now. So, there is no heat hiding in the oceans or elsewhere that would start a rapid runaway heatwave after the activity of the Sun has returned to previous levels.
Mike Ramsey (06:02:21) wrote:
Roger Knights (05:29:30) :
“Excellent, first class. A calm look at reality is what is always needed.”
But it hasn’t been peer-reviewed, nyah, nyah!
“Note that these results were sufficiently surprising that they were confirmed by at least 4 other groups:”
Including a bibliography doesn’t make a paper peer-reviewed. This paper was presented at ICCC and e-mailed to Anthony–that’s all, so far. (AFAIK)
Mike Ramsey continued:
Not sure what your point was.”
I was parodying a typical Insister response to Lindzen. I could have included “/sarc]” at the end, but that sort of nudge in the ribs spoils the joke.
Graeme Rodaughan (03:00:10) :
Ha Ha…. Australia will Rule the next (Frozen) Millenium (Post 3000 AD). Just take my word for it……
And who are you going to play cricket against? No more fast, dry pitches, that’s for sure!
Either Richard Lindzen and pretty much everyone else who has looked at this data is totally wrong or the idea of a large positive feedback, in fact any positive feedback is dead.
Chris V. “If clouds are a negative feedback (as Lindzen implies in the opening post) then the cloud feedback would “resist” the ice ages- not help them along.”
This is shallow thinking. You forget that Milankovitch forcing is heterogeneous. The net change in radiation is tiny, making Ice Ages seemingly impossible even in the positive feedback paradigm. The reason that they are possible is because the Milankovitch forcing alters horizontal heat fluxes. When something strongly resists changes in tropical temperature (a negative feedback)-you will get mean temperature changes. At the poles, the ice albedo feedback helps to. Cheers.
Chris V. (09:22:48) :
In the context of ice ages, albedo is mainly a function of the extent of ice cover, and it is a POSITIVE feedback, not negative.
Warming results in less ice cover; less ice cover means lower albedo; lower albedo means more sunlight is absorbed, which translates into more warming.
Which in turn increases humidity in the atmosphere, which leads to more clouds and precipitation, which cools things down again.
Our planet’s temperature is controlled by water in solid, liquid and gaseous form.
To Jae,
Thank you! I was thinking the same thing, but was uncomfortable expressing it on a scientific blog without the data to back it up. (have pity on me. I’m an engineer turned salesman). I’m looking forward to reading the pdf you’ve linked, which I’ll do now.
See this paper which deals with what I said above:
http://eaps.mit.edu/faculty/lindzen/171nocephf.pdf
Roger Knights on forming bettable questions-
I would submit all the claims of future climate are the equivalent of bets- bets are just a risk analysis of sorts. Congress with the recent budget has shown it does not believe its own global warming rhetoric in that the projects necessary to harden our infrastructure against the ravages of global warming etc are absent. Congress did not take the bet and from their recent actions they assume money has little value- which makes not taking the bet more surprising-it is not their money after all.
Gore made a bet that seas will not rise with his recent purchase in SF. (He also made a bet that the tectonic plate his property is sitting on in SF that is “moving” (undifferentiated slip) ten times faster than the sea is supposed to rise is also unimportant.)
One of my great concerns with the CO2 link to climate is the position being sold to the public that if we control CO2 we are free of climate anomalies and “freak” weather events. Control CO2 and climate does not change. This is a very dangerous if not criminal message. There are very good reasons to be hardening our infrastructure having nothing to do with CO2 but it is being held hostage because taking what might be seen as remedial action lessens the perception of crisis needed to press the larger global warming message.
Chris V:
Have you not considered that clouds may be a negative feedback acting against temperature increases, but not temperature decreases?
Given that one of the major effects of clouds is to increase the earth’s albedo, this seems like a reasonable proposition.
Also, it depends where the clouds are – equatorial clouds have a greater effect on the albedo than polar clouds, similarly clouds over the ocean and clouds during the daytime.
Anthony,
I have a (friendlier) response here
http://chriscolose.wordpress.com/2009/03/31/lindzen-on-climate-feedback/
I hope you can make an update accordingly.
The most dizzy aspect of this has been the ease at which alarmists have produced new observations which they attribute to AGW without
evidence of causation or correlation.
And while they claim, or suggest, these many outcomes are, or may be, a result of human global warming they continue to denigrate skeptics for not having peer reviewed science to support all of their opposing science and counter claims.
Here in Oregon the left and media add daily to the supposed AGW caused harm. Everything they look at they see AGW effect and it gets printed.
While never looking back to the mounting flaws in AGW.
Like many other locales, of course.
Is this an adequate summary?
The IPCC climate models that have now lost most of their reliability.
The Hockey Stick theory relied upon false assumptions that the Medieval Warm period and mini-ice age were regional events and not global climate. Among other flaws.
The IPCC had falsely discounted the impact of urbanization on temperature readings.
Experts have now recognized an effect potentially equal to the entire warming the IPCC had earlier attributed to CO2 emissions.
Along with the Urban Heat Island effect, mis-location of sensor equipment and 70% of rural sensors stations taken off line, it is entirely possible that all or most of the warming attributed to CO2 emissions could be from poor temperature measuring.
AGW whoppers include using weather observations as evidence of AGW. The very thing they disparage skeptics for doing.
The blatantly false connection of AGW to Hurricane Katrina.
Baseless suggestions that heat waves and wildfires are evidence of AGW.
Sea ice fluctuation attributed to AGW without any a validated scientific connection.
California Wildfires blamed on AGW while half were arson.
Similar misrepresentation of Australian fires.
Ocean dead zones have been connected to AGW with no more than a description of a possible connection.
The OSU professor who supposed that connection is now the head of NOAA.
Snow pack reduction is not happening as projected and has never been shown to be AGW related.
Ocean levels are not rising as projected and nothing but assumptions ever connected sea rise to AGW.
Lack of projected symmetry in NH and SH polar cap warming.
Symmetry in NH & SH CO2 increases contradict IPCC theories.
The entirely contrived observation of AGW threatening polar bear populations.
Best estimates show a mere 1 degree F of natural and historically typical global temperature increase over the past 100 years, yet we are believe that all these observations, without any supporting science, are already resulting from the 1 degree and human CO2 emissions?
The craziness of the AGW campaign now trots out predictions of famine, drought, wars, 100’s of millions of climate refugees, agriculture collapse, ocean death, deforestation, and massive heat death and disease. All of which has grown out of faulty IPCC climate models and hypothetical assumptions that never seems to waiver in the face of extensive refutation.
I just don’t think this looks like a “scientific” debate.
tarpon (12:31:11) :
A very Karl Popper question. I start all discussions on the AGW subject with the following question: What information- if it existed -would prove your position on AGW false. If the answer is there is none- there is no reason to continue the conversation. Science must be falsifiable.
In regards to the need for questions- NASA/IPCC should provide the “falsifiable ” information to prove the models wrong. Without an agreed false position no argument carries weight.
Perhaps we should pass a law that states no funding shall be allowed for any scientific research relating to a new crisis unless the falsifiable positions are first posited. The global warming impasse is the result on no agreement as to information that can prove the theory false.
“I dont understand how i can look at a theory and come to the exact opposite conclusions of the person who proposed it”
Because for the person who proposed it (Lovelock) Gaia has become an animate object, rather than a feedback mechanism. He now sees Gaia as taking revenge on the inhabitants (us) for our nasty habits. Everything will be better when our numbers are reduced, which may be true, but it won’t be CO2 that does it.
Dougal Dixon’s arresting book ‘After Man’ suggests that our extinction will be the result of over-exploitation of resources, but goes on to postulate an evolutionary explosion in our absence, in what looks like an unaffected climate!
James P-anyone who speculates about the future has to leave the climate apocalypse out because if it really happened, there wouldn’t be much to speculate about. This probably is a major reason that a futurist like Dyson can’t support it-his vision of an ever advancing human race in which technology emerges to meet any challenge is diametrically opposed to the idea of an insurmountable obstacle like a “climate crisis”. Well, that, and its bunk.
[snip – you have posted under several names and do not provide a valid email address, a valid email address is required to post here]
James P (13:39:45) :
Science requires testable assumptions- Lovelock’s Gaia is philosophical at best (no offense meant to those philosophers heavy on the math) The deep sea vent communities would seem to challenge the single Gaia theory- but again with out a falsifiable place to start we are forced to argue with ourselves. “Black swans” are required.
Peter (13:03:30) :
Have you not considered that clouds may be a negative feedback acting against temperature increases, but not temperature decreases?
That is physically impossible.
Mike Ramsey (06:02:21) :
Your sarcasm detector is malfunctioning 😉
DaveE
kevin: here’s another paper to read. But it will cause much howling, hissing, and gnashing of teeth, if presented to certain people (who think they are much smarter 🙂 ).
http://www.geocities.com/atmosco2/atmos.htm
I am not sure it is correct either, but I have not seen it disproved (at least to my satisfaction).
I am certainly no expert on this subject, either. But I cannot find anyone who IS for sure?? There are plenty of experts out there, including PhD physicists, who laugh at the “atmospheric greenhouse effect.” Their arguments keep me wondering if it really exists. I tend to think it is bullshit, but as I said, I’m no expert….
Chris V., how about addressing my response to your claims instead of the easy pickings?
You cannot simultaneously assert that the Earth’s climate system presently has strong positive feedback on temperature and that the Earth’s temperature is naturally stable absent anthropogenic CO2. The positive feedback on temperature would insure that any temperature changes from whatever source would be amplified until you hit the rail at which the source for the feedback is exhausted.
If you design a circuit with positive feedback, for example, a small voltage increase or decrease will cause the voltage to rapidly hit the upper or lower rail, whichever direction the voltage is going. Hitting the rail means that the circuit no longer has the power supply to push the voltage higher or lower than it’s current state.
Positive feedback in the Earth’s climate should work in the same manner. Look at ice extent as an example. As temperatures increase, ice melts and thereby exposes the underlying surface which absorbs more radiation. But the ice extent decreases which means that the available feedback supply has been reduced. At the point where you are just coming out of an ice age, the potential feedback effect from reducing ice extent is very large – but when you are well into the interglacial, that supply for warming feedback has pretty much exhausted itself, being limited to only polar regions and very isolated mountainous areas. At the same time, the potential positive cooling feedback has been increasing such that, when the Earth’s climate moves back past the equilibrium point towards an ice age, there’s lots of land area that can potentially be covered by ice – tending to increase the speed at whch the climate cools back to the ice age.
Every other positive feedback effect will work in the same manner – it’s simply a fact of existence. Positive feedback in a given direction starts out strong, and consumes itself as rapidly as it’s able until you reach a point where you just cant’t move much further in that direction. At the same time, potential feedback in the opposite direction strengthens.
If you look at the climate record, there is very good evidence of positive feedbacks in the sense that the Earth’s climate rapidly moves into and out of ice ages, but then stays in that state (either ice age or interglacial) for a period of time much longer than the transition time from one to ther other. But the Earth’s climate system itself will exhaust the positive feedbacks during the transition period, after which you have reached the rail – i.e. the stable portion of the ice age/intergalcial that exists until you have a net input in the other direction.
Since we seem to be towards the end of the existing intergalcial, I think it’s absurd to suggest that the Earth’s climate system still has the potential to supply a large positive warming feedback. Quite the opposite – we should be at the point where there are large reserves of cooling feedback sources such that, when the earth does swing back to the negative energy balance phase, those cooling feedbacks will tend to rapidly (on a relative scale) cause glaciation.
Jack Simmons (00:43:18) :
Isn’t this amazing, as the temperature goes up, negative feedback goes up. As the temperature goes down, the feedback starts going positive.
What is even more amazing we can describe it with one word,
Entropy
Lindzen is debunked http://www.realclimate.org/index.php/archives/2007/04/lindzen-in-newsweek/
and the rest of MIT seems to disagree…
http://madrad2002.wordpress.com/2009/03/12/mit-do-you-want-to-gamble-here/
Mike Guerin (23:29:36) : “Is it just me?
Nice to see so many agreeing with you.
Roger Knights, excellent idea this betting… for skeptics, Piers Corbyn is the man I think.
Prof Lindzen, such a cool cool touch to use models to end the models. I luuuuuurve it.
However, I would love to hear your responses to John Philip (despite Steve Goddard’s well-aimed riposte, and my dislike of JP’s language style) and Phil. My experience is that AGW’s get me to really polish and perfect my material, so they have a good function 😎 They end up helping me prove the skeptics science twice as well 😀
Phil. (08:20:31) :
“So Lindzen is demolishing a strawman”
Demanding Lindzen’s argument demonstrate the radiative balance of the entire planet is a red herring, a distraction.
Lindzen isn’t concerning himself with radiative balance as such. He is showing via the study there is a negative feedback affecting LW radiation IN the tropics where the temperatures are the highest. The radiation doesn’t care where the atmosphere or the oceans transport any warmth next. It can all travel to timbuktu or oshkosh.
The models expect a reduction in the escaping radiation due to positive (greenhouse) feedback as the temperatures rise. The higher the temperature the less LW radiation should escape the earth EVEN IN THE TROPICS. But the opposite is the case and by quite a bit.
He calculated the climate sensitivity from this information. If you want to attempt to demonstrate that climate sensitivity changes depending on where you plant your feet, go ahead. But supposedly CO2 is well-mixed and anyway the highest water vapor content occurs in the tropics.
I’ll leave the radiative balance of the entire planet to Spencer.
Mike Guerin (23:29:36) : Is it just me? Nice to see so many here share your feeling.
Roger Knights, nice idea to bet on stuff.
Prof Lindzen, really really cool to use models to end models.
But I’d also like to hear your response to the two warmist posters here who challenged your science. My experience is that warmists really sharpen my wits and get my proof TWICE as strong in the end.
Chris V. (13:52:19) :
That is physically impossible.
Actually, your understanding of feedback is incorrect. If a feedback subtracts from the input, i.e., if the feedback is negative, then it will subtract from the input whether it is trending up or down. In other words, feedback is dependent upon its own sign, not the input signal.
Mark
Matt Dernoga-Oh I’m so scared-the obfuscators in chief at RC have “rebutted” Lindzen’s arguments and, gasp, the got a bunch of smart guys to side with them! Well, they must be right! [snip]
Reply: Let’s raise the bar people, no name calling ~ charles the moderator
Moderator-That’s not a name, its not even a noun, its an adjective. If you’re gonna snip me, get the grammar of my crime right. It was, however, a cheap insult. For that I apologize.
Reply: You are correct it was an adjective, but I don’t recommend calling me on my grammar when you use “its” for it is (twice!), and the first word I snipped was “your” for you are. ~ charles the erring yet contrite grammar nazi moderator.
Matt Dernoga (14:50:37) :
Lindzen is debunked http://www.realclimate.org/index.php/archives/2007/04/lindzen-in-newsweek/
Hardly a “debunking” from 2 years ago… Using the Hockey Stick to “prove” any point is rather ridiculous. That Mann and Schmidt (and the rest of the Team) stick to their proven flawed methodology is rather humorous. I also find it interesting they use an agreement between models and reconstructions as evidence their claim is correct. They, of course, conclude with the tired ad hominem “Lindzen is funded by big oil” refutation. Give it a rest.
and the rest of MIT seems to disagree…
http://madrad2002.wordpress.com/2009/03/12/mit-do-you-want-to-gamble-here/
Hardly “the rest of MIT.”
Nice try.
timetochooseagain (15:14:06) :
No need to sling ad hominems from the skeptic side, his argument is sufficiently pathetic to prove the point you’re intent on making.
Mark
“Mark T (15:01:31) :
Actually, your understanding of feedback is incorrect. If a feedback subtracts from the input, i.e., if the feedback is negative, then it will subtract from the input whether it is trending up or down.”
Actually Chris V. agrees with your point. He stated that it was impossible for a situation where negative feedback applied in the warming direction but not in the cooling direction. I’m not sure that I would categorically rule out that possibility, however. Certainly it would be unusual, and offhand I can’t think of any natural mechanism that would dampen temperature increases but not dampen temperature decreases, or vice versa, but it’s plausible that you could engineer that effect.
The italics should have ended after the Newsweek link, and begun again at and the rest of MIT seems to disagree.
How about some of that auto-quote stuff like over at CA, Anthony? 🙂
Mark
Ouch. Your right! My grammar ~is~ bad! I blame the speed of electronic communication…
Mark T-Heat O’ the moment as they say-RC generally sets off my “AGH!” meter, which triggers irrational rant mode, which is followed by polite discussion and understanding.
kurt (15:27:30) :
Actually Chris V. agrees with your point. He stated that it was impossible for a situation where negative feedback applied in the warming direction but not in the cooling direction.
I disagree. I think that is what the original post said, and Chris V disagreed. Perhaps he, or I, misread the original post, but this:
may be a negative feedback acting against temperature increases, but not temperature decreases?
seems to be exactly what you just said, and Chris V disagreed with.
Mark
Syl (11:27:54) :
“re feedbacks
As I understand it before each glaciation started the Arctic may have been ice free (and sea levels were higher than today). The warmists always warn us that an ice free Arctic will mean less albedo and further warming due to this positive feedback. I think the opposite occurs–negative feedback. Less ice means more ocean cooling. In fact I think this may have been a causitive factor (or I could be all wet) in the cold cold winter we had after the ‘unprecedented melt off’ of Arctic ice a couple of years ago.”
that is a very interesting view.
all the warm water transported to the arctiv can lose it’s energy much quicker without ice cover.
I’m with Ed Fix, George E. Smith and Kevin. I welcome the post by Prof. Lindzen and his courageous opposition to AGW alarmism. But I disagree with his physics of the planet atmosphere effect, the so-called ‘greenhouse effect’.
The blanket analogy is an improvement but is still misleading. A blanket prevents convection; it does absorb and radiate energy. Prof. Lindzen’s post will soon join the list of failed explanations of ‘the greenhouse’ effect in this document, by Gerlich and Tscheuschner.
http://arxiv.org/abs/0707.1161v4
From a physics view it is the average properties that matter, especially density. All the molecules of the air are quite similar. H2O, O2, N2, CO2 and CH4.
Is the Earth emitting radation at 255K? I see the average global temperature given as 13oC, that is 286K.
Appeasing the AGW alarmists by accepting to debate on their terms, greenhouse, forcings, feedbacks and sensitivity is futile.
If someone mentions a greenhouse or a blanket to me I insist they explain how CO2 does it before go further. I soon mention convection. Most AGW alarmists know little or no physics. So it is quickly clear that we are having a political and not a scientific discussion.
Roger Knights (12:43:40) :
Mike Ramsey (06:02:21) wrote:
Roger Knights (05:29:30) :
“Excellent, first class. A calm look at reality is what is always needed.”
But it hasn’t been peer-reviewed, nyah, nyah!
“Note that these results were sufficiently surprising that they were confirmed by at least 4 other groups:”
Including a bibliography doesn’t make a paper peer-reviewed. This paper was presented at ICCC and e-mailed to Anthony–that’s all, so far. (AFAIK)
I was referring to the fact that four cited papers were published in peer reviewed journals.
Mike Ramsey continued:
Not sure what your point was.”
I was parodying a typical Insister response to Lindzen. I could have included “/sarc]” at the end, but that sort of nudge in the ribs spoils the joke.
I suspected but was not sure that you were being ironic which was why I added the above. All good fun.
–Mike Ramsey
Manfred-How exactly would less ice make the oceans lose heat more easily? The ice albedo feedback is actually one of the more convincing, simple, elegant feedbacks-at least in a qualitative sense. Water is less reflective than ice, so it absorbs more light, heating it up, melting more ice, and so on. Are you and Syl suggesting that ice “traps” heat below the surface? How’s that supposed to work?
Roger Clague-Oh really?
http://eaps.mit.edu/faculty/lindzen/198_greenhouse.pdf
timetochooseagain (15:50:16) :
“How exactly would less ice make the oceans lose heat more easily?”
the water temperature in the arctic ocean is higher than the atmosphere’s temperature for most time of the year. heat should should then flow from the water to the atmosphere. the idea is, that ice cover shields the warm water from the cold atmosphere and also from enhancing transport mechanism such as wind.
Manfred-“water temperature in the arctic ocean is higher than the atmosphere’s temperature for most time of the year”
Sorry, that’s setting off my counter-intuitive sense-can you provide a ref? In any case, that would make it a negative feedback in the water but a positive feedback in the atmosphere.
timetochooseagain
Remember, liquid water can never be below the freezing point (of salt water). However, in the high arctic the air above typically is less than 29F. I’m not going to dig up references for the seasonal norms though.
timbrom (12:43:51) :
Graeme Rodaughan (03:00:10) :
Ha Ha…. Australia will Rule the next (Frozen) Millenium (Post 3000 AD). Just take my word for it……
***
And who are you going to play cricket against? No more fast, dry pitches, that’s for sure!
Oh my – I really haven’t thought this plan of Australian World Domination during a Glacial period through – (Runs in circles… screams and shouts…)
Consider the plan debunked… No cricket opponents (although there are the New Zealand team, and Sri Lanka and India are probably OK in a Glacial) – can’t have that.
Chris Colose
Can’t seem to get this comment on your site so I’ll stick it here:
Have you had a chance to look at the references Lindzen said backed up the original data? Presumably they don’t now back up the corrected version, or have they all been corrected too? That ocean heat content data which is now apparently comparable – within the uncertainties – is the same data that was also corrected for apparent cooling errors isn’t it? I’ve not heard yet of a data correction made due to an instrument showing too much warming, ie does it make sense that the corrections always seem to go only one way – towards the prevailing theory. I’d need to read that calibration study you mention but I’ve a funny feeling the corrected algorithm was defined with respect to a model output because that’s how the radiosonde corrections were made. After all, if you knew what the answer should be then you wouldn’t need the instrument measurements in the first place would you? It’s all sort of “cart before the horse”. In that light, can these corrections truly be objective? I’ll be interested in Lindzens response to these charges mind you.
For completeness, the original comment by Gavin on RC on this WUWT post was thus:
“[Response: A good sign of someone who is acting as an advocate is that they instantly take any unexplained anomaly and declare that it fits their prefered theory without doing any actual analysis or without any consideration of the alternatives. First off, the graph he shows was substantially corrected by the authors to remove some spurious aliasing in response to a comment. Secondly, there may still be issues with the data (since there is a clear jump in 1993) – something in any other circumstance, WUWT would have been all over. Third, the models may well be wrong (though it’s unclear these were the experiments to compare with since they didn’t have any forcings), but there is no analysis to indicate that fixing whatever the issue is would give a lower sensitivity – note that the NET fluxes are still all around zero, so the positive feedback in SW is matching the supposed negative feedback in LW. My take on it is very much a wait and see – wait to see if the CERES data seems to support those earlier results, wait to see whether more appropriate model-data comparisons change the picture etc. It may be surprising to some, but ambiguities abound in science and jumping to conclusions is very rarely sensible. – gavin]”
I wish some people could see that the criticism they dish out to others is just as appropriate to describe the behaviour of their own collaborators.
Sea ice changes the boundary conditions for the heat and radiation transfer between water and atmosphere.
The arctic ocean loses more energy than it receives from the sun. That appears to be clear, as the solar input is small and ocean currents transport warm water to the arctic.
Therefore, it may be not sufficient to look only at albedo and only one way (the incoming way) of transport, especially if the other way is the bigger.
“Chris V. (11:48:52) :
If clouds are a negative feedback (as Lindzen implies in the opening post) then the cloud feedback would “resist” the ice ages- not help them along.”
Not true.
You’re taking the wrong datum.
0K is the datum. temperature is all relative to that.
DaveE.
Thank God for Richard. Is he is the only man on the planet who can see the obvious. Keep up the great work Richard. Let the world know what a sham the man made model of global warming is. I say “Down with the New Green Dark Ages”. Let’s bring back common sense, if ever such a thing was common !
[snip – if you have a criticism, justify it. Just calling it names doesn’t qualify.]
What!?
No mention of Atmospheric Window? (Not once)
Wien’s Law? (No mention, not once.)
Steffan-Boltzman? (Once, by 1 poster, different spelling, I searched)
Planck? (Okay, ONCE by one poster)
Citing of radiational (radiated) energy being proportional to T4 (Stefan-Boltzman law)? (Not once)
Not just T-squared mind you, not even T-cubed, but T_to_the_FOURTH power!
How do all these relate?
Simple, using Wien’s Law and earth surface temperatures a ‘peak’ can be calculated that according to Wien will land in the area of 8 to 14 um , the Atmosphereic WIndow for LW IR, with WV (water vapor) acting as ‘block’ below 8 um and CO2 above 14 um, although a little less so than what WV does above … and Stefan-Boltzman’s Law gives us continuous spectral curve with a peak where Wien’s Law specifies…
Is this a coincidence?
Here on Earth?
Hmmmmm ….
Another nail in the coffin of bad science. This article examines the restart of the conveyor belt that had been stilled during most of the past decade. It discusses the large melt in 07-08 that may have restarted the climate system back to cold.
http://www.underwatertimes.com/news.php?article_id=43100678251
Kevin (11:47:43) :
I’m having a problem with this:
“The wavelength of the heat radiation corresponds to the temperature of the earth’s atmosphere at the level from which the radiation is emitted (ca 255oK).”
Is he saying that the Earth emits radiation at 255K? Because that’s just not true. I’m sure I’m just misunderstanding something, and would appreciate someone ’splaining it to me.
Thanks!
Kevin (11:47:43) :
This is how I interpreted the “ca 255°K”. The long wave emissions to space from the troposphere are a summation of all the longwave radiative emissions from surface level to the top of the troposphere. Since there is a gradient from maybe 293°K at the earth’s surface to 220°K at the tropopause, 255°K is the average temperature for the purposes longwave emissions. Dr. Lindzen did say it was a simplistic exposition.
This article:
http://www.dailytech.com/Researcher+Basic+Greenhouse+Equations+Totally+Wrong/article10973.htm
States that part of the negative feedback is the assumption of an infinitely thick atmosphere. Don’t know exactly how it relates to this posting, but it looks to me like this posting is about observations that there is no runaway feedback whereas the article is citing a particular mechanism for it. Synergy?
A quote or two:
How did modern researchers make such a mistake? They relied upon equations derived over 80 years ago, equations which left off one term from the final solution.
Miskolczi’s story reads like a book. Looking at a series of differential equations for the greenhouse effect, he noticed the solution — originally done in 1922 by Arthur Milne, but still used by climate researchers today — ignored boundary conditions by assuming an “infinitely thick” atmosphere.
And also:
So Miskolczi re-derived the solution, this time using the proper boundary conditions for an atmosphere that is not infinite. His result included a new term, which acts as a negative feedback to counter the positive forcing. At low levels, the new term means a small difference … but as greenhouse gases rise, the negative feedback predominates, forcing values back down.
NASA refused to release the results. Miskolczi believes their motivation is simple. “Money”, he tells DailyTech. Research that contradicts the view of an impending crisis jeopardizes funding, not only for his own atmosphere-monitoring project, but all climate-change research. Currently, funding for climate research tops $5 billion per year.
Well worth reading http://www.ianschumacher.com/maximum_temperature.html
if ‘only’ to give a decent, science based reply to that annoying phrase ‘tipping point’….in short it does not exist in the real world, only in fearmongering imaginations.
So Simple, So Beautiful, So Clear.. Dr. Lindzen you are the man!!
This is Science as it was meant. It cuts to heart of the issue, the core of the hysteria around AGW. If CO2 induces negative feedback effects (as it appears to do from the satellite observations and supported in theory by Lindzen’s IRIS effect) then all else is just noise blowing in the wind…
I’m an electrical engineer. When I was in school, I had a whole semester devoted to stability of control systems with feedback. One thing I learned: When a control system with a significant positive feedback is allowed to run for very long, it will eventually hit some condition that drives into saturation (i.e., it surges to its limits).
A simple test of a control system’s stability is to hit it with an impulse. For example, if you turn a PA system’s microphone gain up just short of squeeling, it’s fine. But clap your hands together and it takes off.
What does that mean for climate? Think about the apocalypse that killed off the dinosaurs 65 million years ago and the various volcanic eruptions that caused major climate shifts. These were impulses that caused severe shifts in the system. Like the analogy of the PA system, climate showed no evidence of positive feedback to these impulses; otherwise, the climate would have never recovered to modern, hospitable levels.
If Earth’s climate system had positive feedbacks of any consequence, the planet would have turned into a ball of ice or another Venus millions of years ago in response to all the meteorites and volcanic activity that have upset the system.
It’s a no-brainer to anyone with a little common sense, but who said these scaremongers had any sense?
R Chris V. (06:41:10) :
If the climate sensitivity is only around 0.3 degrees, how do we get ice ages?
Nobody knows. Some people have hypotheses. Some hypotheses have “greenhouse” gases playing a starring role, some don’t.
Comparing temperatures during the last glacial maximum to today yields a climate sensitivity of about 3 degrees +/- a degree or so (basically the same as the models get).
You can derive this sensitivity if you assume greenhouse gases play a starring role. If you hypothesize other mechanisms, you don’t need this much climate sensitivity.
If the climate sensitivity is only 0.3 degrees, that implies that there is some HUGE completely unidentified forcing responsible for taking us into and out of ice ages. That could be, but it seems unlikely to me.
So you imply that the “greenhouse effect” is HUGE because you feel that there are no other HUGE forcings that seem likely. It is kind of like rounding up “the usual suspects”. It may be a valid hypothesis but it is yet only a hypothesis. Not having other suspects does not elevate it to theory. Climate science is in its infancy and climate dogma only impedes the acquisition of knowledge.
Robert Austin-the best explanation is still the heterogeneous Milankovitch forcing, which, as Lindzen has noted before, would alter equator to pole heat fluxes even though the net change in radiation is small. Coupled with strong negative feedback in the tropics, that would lead to mean temperature changes. The fact that Chris V hasn’t addressed this argument shows that he isn’t making his argument to illuminate anything, but to further an agenda.
See here:
http://eaps.mit.edu/faculty/lindzen/171nocephf.pdf
Ice ages are most likely based on our Earth’s wobble as it spins on its axis. Every 10,000 or so years the wobble produces a greater tilt away from the Sun, thus receiving glancing blows from the Sun’s heat during the Summer (and hardly making it to Earth during the Winter), leading to much cooler temperatures and less Arctic ice melt.
Pamela Gray-The change in net radiation is itself small. The real key is the change in the ~distribution~ of incoming solar radiation. See my comments above. 🙂
Mark T (15:01:31) :
Actually, your understanding of feedback is incorrect. If a feedback subtracts from the input, i.e., if the feedback is negative, then it will subtract from the input whether it is trending up or down. In other words, feedback is dependent upon its own sign, not the input signal.
No, your understanding of feedback is incorrect. As is used in climate science, a positive feedback amplifies the signal. If the original forcing is warming, then a positive feedback increases the warming. If the original forcing is cooling, then a positive feedback increases the cooling.
Think of ice albedo (which is a positive feedback). If the earth warms, you have less ice. Less ice means lower albedo, so less light is reflected, which increases the warming. If the earth cools, you get more ice. More ice means higher albedo, which reflects more light, and increases the cooling.
JamesG (16:46:22) :
Chris Colose
For completeness, the original comment by Gavin on RC on this WUWT post was thus:
“[Response: A good sign of someone who is acting as an advocate is that they instantly take any unexplained anomaly and declare that it fits their prefered theory without doing any actual analysis or without any consideration of the alternatives. First off, the graph he shows was substantially corrected by the authors to remove some spurious aliasing in response to a comment. Secondly, there may still be issues with the data (since there is a clear jump in 1993) – something in any other circumstance, WUWT would have been all over. Third, the models may well be wrong (though it’s unclear these were the experiments to compare with since they didn’t have any forcings), but there is no analysis to indicate that fixing whatever the issue is would give a lower sensitivity – note that the NET fluxes are still all around zero, so the positive feedback in SW is matching the supposed negative feedback in LW. My take on it is very much a wait and see – wait to see if the CERES data seems to support those earlier results, wait to see whether more appropriate model-data comparisons change the picture etc.
ok lets change the picture.
sw flux anomaly erbe/isccp
http://i255.photobucket.com/albums/hh133/mataraka/cloudeicomp.jpg
sw anomaly erbe and ceres
http://i255.photobucket.com/albums/hh133/mataraka/ceres.jpg
The International Cloud cover climatology project Icccp is well detailed Kondrateyev (1983). The parametrized schemes to climate sensitivity are part of a number of international projects eg Scaraab, and ERB Marchuk1988 and UKMO Saundes and Mitchell 1988.
With UKMO the scheme is 11 layers.ie 3 with lower,middle etc. plus convective.
Each series has 3 schemes
1)Relative Humidity (rh)
2)Cloud water (CW)
3) Cloud water radiative properties (CWRP)
Enumeration in the UKMO model had the following RH with strong positive cloud feedback, CW was neutral, and CWRP was negative this underlies the importance of correct parametrization with cloud climatologies.
As we see all phases are possible then why do all the models only include positive feedbacks eg Isaac Held.?
The importance of SW forcing (ie in the absence of cloud or Ozone attenuation is a significant issue eg Pavlakis et al 2008
Figure 6b shows the time-series of the DSR-A (black line) in the central Pacific region (7 S–5 N 160 E–160 W) and on the same diagram we have overlaid the time-series of the Ni˜no-3.4 SST index (red line). The DSR-A is out-ofphase
with the Ni˜no-3.4 index. There is an excellent anticorrelation between the Ni˜no-3.4 index (a sea parameter) and DSR-A over two neighbouring regions: the Ni˜no-3.4 region and the central Pacific region. The latter reflects mostly the
variations in cloud amount caused by atmospheric circulation anomalies. We have calculated the 3-month smoothed anomaly of the mean monthly total cloud amount with respect to the average monthly total cloud amount for the study period 1984–2004 for the central Pacific region. A linear regression between the DSR-A time series and the total cloud amount anomaly time series yielded a correlation
coefficient of r=−0.91 (anti-correlation) showing that cloud amount variations are the primary determinants of the DSR variability.
http://i255.photobucket.com/albums/hh133/mataraka/dsrregions.jpg
The Effects of Sea-Ice and Land-Snow Concentrations on
Planetary Albedo from the Earth Radiation Budget Experiment
Gorodetskaya et al 2006
ABSTRACT The high-latitude ice/snow-albedo feedback is a principal element in many paleoclimate theories and global warming scenarios. The strength of this feedback is determined by the ice/snow effects on the top-of-atmosphere
(TOA) albedo, which is also strongly affected by clouds. Using currently available satellite observations, we estimate the radiative effectiveness (RE) of ice and snow with regards to the TOA albedo, which we define as the change in the TOA albedo corresponding to changes of 0% to 100% in the ice or snow cover. The REs of the
northern hemisphere (NH) sea ice, land snow, and southern hemisphere (SH) sea ice are found to be 0.22, 0.23 and 0.16, respectively. This means that, for an incident solar flux of about 400 W m–2 reaching the TOA in the polar latitudes in summer, local reduction in ice/snow concentrations from 100% to 0% will result in a decrease in reflected short wave radiation of approximately 80 W m–2. These changes in the TOA albedo are significant, yet smaller than the associated changes in the surface albedo. Comparison of the TOA albedo values with available surface
albedo observations helps to identify the role of clouds in the RE of ice/snow. The analysis is based on the whole time-space domain where the sea ice and land snow appear, and reveals a remarkable similarity in the ice and snow RE in the areas with high sea-ice and land-snow cover variability, despite the varying nature of the surface cover, seasonality, and locations. These estimates provide a useful constraint to test current climate models.
timetochooseagain (14:36:21) :
Chris V., how about addressing my response to your claims instead of the easy pickings?
I’m not sure I understand your original response, but here are some numbers for you to mull over:
According to Lindzen, the climate sensitivity to CO2 doubling is 0.3 degrees. The radiative forcing from CO2 doubling is about 3.7 W/m2.
The climate responds pretty much the same to any radiative forcing of the same magnitude, so any change in radiative forcing of 3.7 W/m2 (from a change in solar irradiance, say) should also change temperature by 0.3 degrees.
During the last ice age, the earths temperature was (off the top of my head) something like 5 degrees colder.
So if 3.7 W/m2 yields a temp change 0.3 degrees, the total radiative forcing needed to change temperatures by 5 degrees would be about 60 W/m2.
For comparison, the total solar irradiance striking the top of the atmosphere is about 350 W/m2; the amount of solar radiation absorbed by the earth is about 170 W/m2.
Where the heck does that 60 W/m2 of forcing come from???? 60 W/m2 is HUGE- that’s 1/3 of the solar irradiance that is absorbed by the earth!
FYI, the total ice albedo forcing during the last glacial maximum has been calculated to be only 5 or 6 W/m2.
Robert Austin (19:21:58) :
See my previous response to timetochooseagain.
Michael Hammer came to a similar conclusion, using a different approach here:http://jennifermarohasy.com/blog/2009/04/role-of-water-vapour-in-climate-change/
Chris V-Failing to understand my response is not an excuse for simply restating your argument an totally ignoring the point that I made.
“The climate responds pretty much the same to any radiative forcing of the same magnitude, so any change in radiative forcing of 3.7 W/m2 (from a change in solar irradiance, say) should also change temperature by 0.3 degrees.”
This is true of spatial heterogeneous forcings-but Milankovitch forcing is not heterogeneous!
Chris V. (22:04:33
Where the heck does that 60 W/m2 of forcing come from???? 60 W/m2 is HUGE- that’s 1/3 of the solar irradiance that is absorbed by the earth!
You do know how zonal climatology works eg Z. T. Guo et sl 2009
The cause of the enhanced asymmetry of hemispheric climates
during MIS-13 remains to be addressed. Greenhouse
warming may cause similar asymmetry of sea ice (Manabe
et al., 1992; Cavalieri et al., 1997), but cannot account for
MIS-13 because of its lower CO2 and CH4 levels.
Insolation is a possible cause. Although the CO2 concentration
was 40 ppmv lower (Luthi et al., 2008) in MIS-13
than the pre-industrial level (equivalent to a radiative forcing
of −0.82Wm−2), high northern latitudes received more
energy during their summer when this season occurred at
perihelion, i.e. three times in MIS-13 at 529, 506, and 485 ka
BP. For example, summer insolation at 65 N was 50Wm−2
higher at 506 ka ago (Fig. 2f) when eccentricity was much
larger (Berger, 1978). The consequent net increase of energy
received by the northern high-latitudes would favour
ice melting. On the contrary, summer insolation at 65 S
was 50Wm−2 lower (Berger, 1978) at 506 ka ago. This, associated
with the lower concentrations of greenhouse gases….
….(Loulergue et al., 2008; Luthi et al., 2008), would favour
ice building in the Southern Hemisphere. This also happened
at 485 ka BP, but at 529 ka BP the amplitude of the
seasonal anomaly was reduced due to a lower eccentricity.
On the other hand, insolation anomalies at MIS-5e were
even larger than at 506 ka BP due to a larger eccentricity
(Berger, 1978), consistent with the stronger summer monsoon
(Fig. 3a), weaker winter monsoon and lower dust intensity
in Asia (Fig. 2e and 3a). In addition, MIS-13 and MIS-
11 coincide with a mid-Pleistocene interval of lower amplitude
changes of summer insolation at northern high-latitudes
(Berger, 1978) from 570 to 340 ka BP (Fig. 2f). The higher
values of the insolation minima would oppose ice building in
the Northern Hemisphere.
Chirality a paradox for paleoclimates and Global “averages”
I think Prof Lindzen is winning, so far.
timetochooseagain (22:25:49) :
Yes- the changes in albedo resulting from the Milankovitch cycles are concentrated around the north pole. I’m not sure why that matters- are you implying that the extra 55 W/m2 of forcing comes from changes in atmospheric/ocean circulation?
Doh! That should be “homogeneous”-of course Milankovitch forcing is heterogeneous-I meant it is not homogeneous! Gah! How’d I miss that?
Chris V-OMG-there is no “extra” forcing, there doesn’t need to be. Milankovitch cycles alter horizontal heat fluxes, which in turn result in mean temperature changes provided the feedback in the tropics is strongly negative. Jeez!
http://eaps.mit.edu/faculty/lindzen/171nocephf.pdf
The only way you get away with claiming that an “extra” forcing is needed is by focusing on the small net radiation changes in the Global Mean Radiative forcing-but that kind of analysis is not appropriate for heterogeneous forcing like milankovitch cycles. You need to get out of your “Yes, but if we focus on the Global Mean…” mindset here or you will never understand the point I’m trying to make.
dhogaza (21:43:47) :
[snip – juvenile rant]
dhogaza (21:48:30) :
[snip – off topic, Don you don’t get to run this thread]
30 03 2009
dhogaza (21:57:27) :
[ snip – Let me make this clear, we are not going to talk about smoking and cancer on this thread, call me what you want, complain all you like here or to your buddies over at Tammy or RC, but it is not going to happen. If you have something to say about the science presented here you are welcome to say it. – Anthony]
Don,
This is an example of negative feedback…..
Chris V,
Solar irradiance at ground level is about 1000 W/sqm. Total solar irradiance in orbit is about 1,350 W/sqm. Anybody messing about with solar panels can tell you that.
Roger Knights (12:43:40) wrote: “I was parodying a typical Insister response///”
Think most of us picked that up right off, Roger. “/sarc” should not be necessary, and always seems somewhat juvenile to me. If sarcasm (or a joke) needs flagging, then it ain’t.
Steve G, Fred M and Lucy S.
Its very simple – the graphic in Lindzen’s article is from the 2002 paper in science. This paper was the subject of a comment and later correction. Chris Colose has usefully published the corrected graphic in his response, in which most if not all, of the model/obs mismatch is eliminated.
Either Prof Lindzen is unaware of the correction, which I find impossibly unlikely, or he has knowingly circulated incorrect information to support his case, an act that one might normally expect would attract severe opprobrium from the posters of an objective science blog such as this. Neither possibility does much for the pursuasiveness of his argument, in my view. Certainly if the Professor were to submit this article for publication, it would be rejected on these grounds alone.
REPLY: There is a third option, perhapss he doesn’t trust the “correction”. I know that many of us here don’t trust “corrections” applied to data. For example most GISS corrections of weather station data for homogenization are the wrong sign. – Anthony
REPLY2: John I have deleted your response, and I resent the smear you made against me for publishing this informal essay from Dr. Lindzen. You get a 24 hour timeout. If you wish to continue, lose the ad homs. Otherwise off to the troll bin permanently for you. – Anthony
Glad to see Lindzen citing his peers for their need for perspective. I’m sure any number of observers has pointed out that the warmist case has seen as more not seeing the forest for the trees than real disingenuity.
The question is whether we’re headed for a catastrophe. It’s too facile to exculpate CO2, but it’s too capricious to have taken 15, then 25 years of data and modeling and declare a certain trend with so many unknowns when the atmosphere and seas are so bloody complex.
From the source code I’ve seen & the critiques flying about, seems to me that fluid dynamics is best modeled using cellular automata, not formula-based statistical models. The problem is that in order to model the Earth’s atmosphere available computing power probably needs to be increased 1000 fold & a new generation of GCM developed.