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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Craig Allen’s reference to the collective “so called experts” and noting that Lindzen is one with real credentials can be interpreted different ways.
Really? CA called Lindzen “one of the so called experts” which is an insult whichever way you slice it. Drawing attention to this or asking for an apology is not getting personal – making the original comment is.
IMO, we who reject AGW are the patient and generally polite ones, but it takes a lot of willpower in the face of such mendacity and disinformation. How much damage should we put up with?
FYI Dr. Lindzen sent me a response today, for which I am grateful that he took time from his busy schedule to do.
I have posted it as update #3 in the body of the article. – Anthony
Thanks to Dr. Lindzen and Anthony for the update.
“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”.
In short, we are being screwed!
What further proof do you want for the fact that science is politicized!
OK, since I have to get into grammar, the phrase, “so called,” means, “those who are called,” and is not always derogatory. For example, if I said, “Stevie Wonder is one of the few so called musicians who actually sings exactly on key,” am I insulting Stevie Wonder?
Since I anticipate more of this, let me use as an example an often cited passage in Josephus, Antiquities, XX 1:9 which is sometimes translated, “Jesus, the so called…” or “Jesus, who was called…” It was just his literal recording of what someone was called and nothing more. Both translations are common.
The meaning of the term is debatable. Whether or not Craig used the best syntax is not a worthy subject here.
Lindzen’s reply is MUCH more interesting.
Good on Dr Lindzen,
He rises in my estimations a notch. I await his update eagerly.
And while I didn’t per mean to imply the his expertise was “so called” by placing him grammatically so close to other “so called experts”, I can see how I left the door open in that sentence for the rhetorical games of other posters.
So Dr Lindzen, I apologise unreservedly for any offence I may have caused you.
Oms:
Yes, I considered that, but when you eyeball the adsorption spectra (neatly presented here) you can see that the location and size of the CO2 band within the thermal radiation absorbing section of the spectrum looks about right for it to be accounting for 9%.
And besides, this is the fundamental core of the greenhouse hypothesis. It’s at the heart of every climate model. The whole notion stands and falls by this. A scientists who proves it seriously wrong (assuming I haven’t made a dumb mistake – I’d hate to be seen to be setting up a straw-man!) will be famous forever. You’d have to think it is pretty much nailed down by now.
Ian:
I looked over your list of arguments. I am in fact very much interested in the arguments contained therein. I’ve seen most of them discussed and debunked in various other fora. Some of these are amazingly easy to refute. (Any conclusions drawn from unbelievably Beck’s dodgy CO2 measurement melange for example. Or how about the Greenland and grape growing in England bogies.) Others take a little more time. I guarantee that there is not a single one you might like to choose that I could not demolish. Please choose one. I enjoy the exercise. (Mind you, I’m, about to move house, so I’m about to leave you all in peace for a week or two. Won’t that be a relief.)
James P;
So which particular card brought the house of cards down for you? I hope that as you consider it further you will realise you’ve abandoned a house of bricks to take up residence in a house of straw.
Craig Allen, being in the throes of Cognitive Dissonance, has already made up his mind and it’s shut tight. As a result, he will blithely assume he has “demolished” anything that threatens his CD.
OK then, for the rest of the folks who have an open mind, here’s a medium length graph of temps: click
Notice it’s data from GISS, HadCRUT, RSS and UAH. Unless they’re all in some kind of conspiracy, they all show current temps are now below the 30-year trend, and dropping fast.
Same here: click Note that the planet’s temp is below the zero point trend line. That means it’s cooling.
Is three decades too long? OK, here’s a more recent chart: click Dang! There’s that unexpected cooling again.
And what about that evil carbon dioxide? The tiny trace gas that’s gonna push the climate over a nasty tipping point, causing runaway global warming: click Oh well, back to the GCM drawing board… oh, wait. Now I remember. Global warming causes global cooling! Of course.
Here’s our old friend GISS, showing that they’re out of step with the consensus: click Notice the GISS trend line compared with the others. It appears that someone is “adjusting” their numbers.
Another Temp/CO2 chart: click. Someone had better notify the UN/IPCC: “Bali, we have a problem.”
Here’s a more intermediate chart: click. Maybe everyone is lying except Al Gore, huh?
Hadley weighs in: click. Never fear, Cognitive Dissonance will find a way to argue around it.
Polynomial bait: click. Forget the trend line. But notice the planet is at about the same temperature as it was in 1982. Sorry about busting the GW bubble.
Another 30-year chart: click. Everybody panic! …NOT.
Maybe a century long chart will show the planet is warming: click. Nope. Sorry.
Think the planet’s been here before? click. Yep. Pre-SUV, too.
The UN/IPCC AR-4 falsified by Lucia: click. But what else can we expect from 100% political appointees? The truth?? No, there’s too much money at stake. Those appointees have their marching orders.
Maybe those charts just don’t go back far enough to show that CO2 causes runaway global warming: click. Well, so much for that conjecture.
But the models! They say the planet is heating up, and the GCMs are never wrong, are they? click. Well, it turns out they’re almost always wrong.
EVERYBODY PANIC!! Click …not. Ho-hum.
Been there, done that, got the T-shirt: click
OK, gotta go, but I have plenty more like these. In the mean time, sorry about that AGW/CO2 conjecture: click.
For pities sake Smoky:
Fit a regression line through those plots. It’s slope is significantly positive.
But for any of the following short excerpts the trend is significantly negative.
1981- 1983
1983 – 1985
1987 – 1989
1990 (and a half) to 1993
1995 – 1997
1998 – 2000
2007 – now
You are trying to use short term noise (caused by phenomomen such as el nino/la nina and the Indian Ocean Dipole) to refute a long tern trend which is up up up.
Looking at it another way. Compute the average for the last ten years and compare it to the average for any previous decade. It is significantly higher.
You even go so far as to present a graphic showing 30 years of data, but then compare the value of just two of the data points!
If scientists did this the ~snip~ would go apoplectic! And they would be right to do so (ignoring the minor issue of hypocrisy).
Smokey (19:49:14) :
Nice set of graphs. I like the first one the best. All of this sophistry on the AGW side about how we are all idiots and well … given the only set of reliable temperature measurements we have there doesn’t even appear to be any warming at all. Never mind explaining the warming .. what warming? The emperor has no clothes.
Actually that is one of the aspects of this I find the most interesting. The AGW anger. This is epitomized in the theme of the new movie “The age of stupid” i.e. we the skeptics are well … so incredible stupid LOL and this makes the believers really angry. They just can not believe that maybe, just maybe, they might be wrong. I’m willing to believe I am wrong as is any true skeptic. Being a skeptic means that you are ‘skeptical’ not that you believe the opposite. While AGW seems blatantly obvious to the believers, we take a look at the graphs and ask “warming, really? where? Catastrophic you say … nothing like this in history before?” … pauses to look at more graphs, ice-ages, MWP, LIA looks at photos of temperature stations beside air conditioners, on top of pavement, water markers in Maldives that are still visible, historical accounts showing that warm periods actually seem to be beneficial … “Catastrophic … are you sure?” LOL.
Go to a skeptic site, what do you see. Data, graphs, references, thoughtful discussion, courtesy, interesting thoughts, interesting anecdotes, humility. Go to a believer site, what do you see. Insults, personal attacks on good scientists, outright dismissal, contempt, arrogance. They don’t even bother to address questions except to say how unbelievable stupid you are for your ‘obvious’ misinterpretation of even that most basic science. Ahhh ok …
Anyways that is kind of fascinating. Seeing mass social delusion develop and flourish right before our eyes .. just like we read about in history books and thought could never happen again .. not in this era of science …
Ian Schumacher,
I’d argue the exact inverse.
This article – Blind to Facts and Reason: The Role of Ideology – reflects my understanding of the relationship between the two sides of this debate pretty well.
And consider this, where does almost all of the primary data and presentations of it come from? Climate scientists and the many climate science publications and websites that provide it to the public.
There is a big list of the primary data sources here where you can go to download the raw data. You will find that not one of the institutions providing the data disputes the AGW hypothesis.
Same goes for all the Worlds major scientific academies”.
Craig Allen (18:43:10) :
You said you would could address any of my talking point and provide strong evidence against any of them (I am paraphrasing). Ok, that’s cool, in all seriousness I am interested in counter arguments. Why not start with point #1. No significant trend. Lets stick with the satellite data if possible. There is a trend. If one assumes a linear fit is the best fit and does linear regression there will be a positive slope. That we agree on, so my question would be:
1.) What is the error of the slope i.e. is the slope statistically significant and how significant i.e. 1/1000 this slope could occur randomly.
2.) What evidence do you have this level of change is unprecedented? Has never occurred in the past and could not be due to natural variability (within reasonable probability of course). i.e. proof that the MWP and/or LIA did not exist.
3.) If the trend is within natural variability (which I think it is, pending your proof against it of course), would you conclude that there is room for doubt/skepticism and if not, why not? Of course no need to address this depending on #1 and #2.
I will look at your links tomorrow. I have downloaded and plotted the ‘raw’ data. That is what point #1 is, but I’ll take a look a tamino links tomorrow also.
Cheers,
Ian
Re: Craig Allen:
In your argument, you chose the lower value for CO2 in isolation, and then found the linear calculation “confirmed” by observation, with space to spare on the upper side of temperatures due to feedback.
However, CO2 warming does not exist in isolation in any climate model. At the least, the very large H2O feedback (larger than CO2 sensitivity by itself!) must be included.
Hence if you were to choose a single number for effective sensitivity (without the feedback calculation), 9% would be a bit “coincidental” to arrive at a 0.675°C figure which happens to agree with observed warming, when the upper bound of 26% would have been much more defensible with feedbacks included.
I think it would be fair to point out the difference in content between the various agreements that human activity has an effect on the earth’s climate, and a strong assertion such as the IPCC 2007:
Craig Allen (22:14:43) :
There is a big list of the primary data sources here where you can go to download the raw data. You will find that not one of the institutions providing the data disputes the AGW hypothesis.
Same goes for all the Worlds major scientific academies”.
I would like to remind you that if scientists were not able to break through this consensus mentality, of ” all the worlds major scientif academis” we would still be in the middle ages counting the number of angels on the end of a pin.
Science is not about voting, or consensus. Science is not about data gathering, though honesty in data gathering is important ( and this blog has shown great errrors in that, if not dishonesty in the land temperature data). Science is to be able to make hypothesis about the data and see if they hold, and to have integrity enough to throw away the hypothesis that does not fit the data.
Any “model” that is not falsifiable is not part of science, but video games, world views,political theories etc.
Craig Allen
I’ve watched the debate between you and Smokey. Let me come clean. While I agree with Smokey’s conclusions, and like the approach of giving snappy references, I often have sympathy with you as you are generally courteous, and sometimes (eg the Tasmanian sealevel mark) I feel your input trumps that of Smokey. I will further come clean: I too get ratted and descend into invectives at times. But I do two other things as well: I apologize, and I often learn from the warmists and say thanks – and mean it – because you warmists have really helped me sharpen up my attention to data, details, and what to put first – BEFORE ATTENTION FAILS.
Skeptics have been disjointed in their evidence. And yes, we often lack consensus. However, the real cutting-edge of Science is untidy and could never progress unless lone voices spoke out against consensuses. And the history of Science shows that these lone voices have often been treated not just badly but very badly. Sometimes they eventually win and become part of the new consensus. Sometimes they stay buried for a long time. Faraday’s observations of the liquid condition existing in ice (on its surface in particular) is one of those – and it’s relevant to the capacity of Vostok to record CO2 levels accurately.
The creative edge of Science is untidy. The transmitted tradition of Science is the very opposite: beautiful, clean, simple-looking laws that explain Reality. These two contradictory aspects of Science attract very different kinds of people. Most people want simple, clean truths: but are unwilling to dirty their hands to get those simple distillations for themselves. Anything messy HAS to be wrong. Anything outside the box, not agreed by the “experts”, HAS to be wrong. See, I too have difficulty, from my side, with the use of that word “expert”!! It is the rarity amongst experts who like everything clean and neat, to find one who is also open to the creative edge of evidence that does not fit. Lindzen is just such a rarity. Always such paradigm-shifters have been attacked – read Thomas Kuhn “The Structure of Scientific Revolutions”.
Now we are at a great paradigm shift: maybe each of us has to be a lot more responsible for our effects on a fragile planet. However, most of those who face this do so from urban environments that have lost almost all sense of sacred connection with Nature. Technology, enabled by Science, often seems like the bogeyman. But it is not. Science and Technology are also gifts: but their first requirement is that all theory must fit all available data. And the CO2-drives-temperature theory does NOT fit ANY of the available data. We all know it’s a greenhouse gas that probably stops us freezing. But there is NO evidence for CO2 having any warming power at current levels. See my Primer (click my name) on this; show me where I’m factually wrong; if you can, I would be grateful. But give me space to respond in case you’ve missed my point because I worded it badly.
If you like, join our Forum: but it’s only a small Forum unlike WUWT.
James P;
So which particular card brought the house of cards down for you?
Well, since you ask…
I originally accepted the general AGW consensus unthinkingly, conflating it with other environmental issues with which I agreed, such as pollution/waste reduction and sustainability. I have a long time friend who likes to play devil’s advocate and who realised long before me that this was a scam. If I mentioned CO2, he would ask how I knew it was a greenhouse gas, knowing that I then spent some of my time actually working in greenhouses where, ironically, we would pipe extra CO2 in to help the plants grow faster! This prompted me to check the numbers, and we had people working quite happily in an environment with over 1000ppm, so I had to find out a bit more about its contribution to GW, which seems to be rather less than advertised. The A of AGW seems to be 3% of the overall 0.04% which doesn’t sound a lot to me.
We also discussed carbon trading, both concluding that this is pure hokum. Planting trees, while a worthy occupation, simply defers the release of the carbon while the tree is alive, so it is, at best, only a temporary measure. In any case, by now, I had come to question the whole business of ‘climate change’ and its political exploitation. A science project into our local red squirrel population (I live in the Isle of Wight, where the grey variety is absent) found that normally hard to acquire funding became magically available when they linked the study to global warming!
Other signs that political capital was being made included the car tax changes in the UK (now based on CO2 emissions) and the promotion of CFL bulbs, for which the law of unintended consequences could have been invented (cheap to run, but expensive to make and recycle, use noxious materials, have an unpleasant spectrum and use more power than advertised due to an awkward power factor).
I remembered the big ‘ice age’ scare in the 70’s and via blogs like this discovered that James Hansen had had a part in that too, which I’m sure is something that no longer appears on his CV! I also found this, which is one of the best expositions of a technical subject I have ever read. I am a technical author by trade and I appreciate this sort of thing.
http://bishophill.squarespace.com/blog/2008/8/11/caspar-and-the-jesus-paper.html
As one of the commenters wrote of the AGW protagonists: “If everything is settled in their favour, why are they resorting to this sort of mendacity?”
Why, indeed.
I’m a simple man: However the negative feedback effect how strong is it? I mean if the earth negative feedback system is constantly adjusting and tweaking to maintain temperature equilibrium does that mean the temperature can never really change up or domwn that much, which is evidently no the case.
So my question is can the negative feeback response be overwhelmed by factors like the Milanokovich model.
Thanks
Ian Schumacher (23:42:50) :
#1. No significant trend
Is this any use ? Although they do admit it a more simple approach than using the GCM s
http://estaticos.soitu.es/documentos/2008/12/warm.pdf
PeteB (07:50:47) :
Yes that is interesting and I agree with them for the adjusted surface temperature record. UHI and the bizarre adjustment process (historical temperature being revised down, current temperature revised up) explains this for the surface record. But I’m still interested in their methodology.
That’s why i think the surface record is useless. The built-in and manufactured bias far out ways any GW signal. This means only the satellite data is reliable and unfortunately we only have a short amount of data for that.
but if you compare surface temperatures over the satellite era between data sets
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1979/trend/plot/rss/from:1979/trend/offset:0.15/plot/uah/from:1979/trend/offset:0.15/plot/gistemp/from:1979/trend/offset:-0.1
(I’ve offset to try to compensate for different base periods)
hadcru, rss and giss have nearly identical trends with uah slightly lower which makes me think the surface temperature record isn’t that far out.
There is still a disceprancy between the 30% higher trend you would expect from the models in the global lower trop record and the surface temperature. That could be
1) Models are wrong
2) Surface Temperature record overestimates the true warming
3) Satellite temp are wrong (there’s a significant difference between UAH and RSS based on the same data !) and some of the other satellite records e.g. Fu et al. (2004)finds trends (1979-2001) of +0.19 °C/decade when applied to the RSS data set.[6] A less regularly updated analysis is that of Vinnikov and Grody with +0.20°C per decade (1978–2004) show much greater warming (again based on the same data)
4) Some combination of the above
Re Surface Warming
This also gave me some confidence in the surface temperature record – John V took the raw data from ‘good’ stations, used his own methodogy and compared it against the GISS. Unfortunately the graphs no longer show up but there was near total agreement from the trend calculated independently by John V from the good stations (he did this for USA only) and the GISS record (with what I agree is a rather confusing methodology !)
http://www.climateaudit.org/?p=2061#comment-137949
Whatever happened to the Open Temp project ?
Yes over the satellite era the surface temperatures match fairly well, but the data keepers are constantly adjusting the data so I don’t think this is a reason for confidence, more likely a condition of the adjustments (i.e. they can’t disagree with the satellites too much and are adjusted so they do not ).
Most skeptics believe there has been warming, they just believe that it is due to natural cycles, the sun, etc. I’m a bit rare in that I’m ‘skeptical’ about whether there has even been any warming. It is my understanding that even the satellite temperature have been adjusted, although only a small amount. I can not believe in the corrections when the corrections always (to the best of my knowledge … any one know of a counter example) result in increased warming. Its just too improbable, and obvious to anyone with a hint of objectivity — fraudulent.
When you combine these small but many one-way adjustments, the sparse and poorly distributed sensor network, UHI, and other factors, I think people forget exactly how small the supposed warming is. It was 0.64C supposedly before they did a bunch of adjustments and made it 0.8C. That’s a 0.2% change in temperature. To me, if we took out the obvious bias of the constant one-way adjustments, took UHI into effect properly, then I doubt we would see any warming beyond noise.
Take a look at sea level rise as another example. We are told it rises a few millimeters a year. That is fine in theory, but how do we ‘know’ this? The equipment we are using (tide gauges) where not designed to detect differences this small over such a long period of time. The satellites are calibrated to the tide gauges (another one-way adjustment). Maldives being a very good counter-example of actual visually verifiable data where there is no detectable water rise and where if there was, they should notice it.
My opinion is that everyone is arguing over noise and ‘adjusted’ noise at that. First, let’s adequately explain the ice-ages. Let’s have a model of the ice ages that fully explains what happened. It boggles my mind how the science community can go on modeling noise and pretending they understand when they don’t even have an adequate model for ice ages where there is an actual and obvious ‘signal’. Let’s understand massive climate change first before we spend billions of dollars trying to explain undetectable climate change.
http://www.ianschumacher.com/iceages.html
Ian Schumacher (09:35:10) :
Yes over the satellite era the surface temperatures match fairly well, but the data keepers are constantly adjusting the data so I don’t think this is a reason for confidence, more likely a condition of the adjustments (i.e. they can’t disagree with the satellites too much and are adjusted so they do not ).
Yet when the satellite data was first produced there was a very large discrepancy with the surface data. By your logic the surface data would have been adjusted to match the satellites, in fact that was not done, however errors were subsequently found in the satellite data and the discrepancy reduced.
Phil. (09:57:26) :
By your logic the surface data would have been adjusted to match the satellites,
Actually, by his logic the satellite data would be adjusted to be a closer match to the surface… which was what happened.
Mark
Yes, ‘errors’ are always being found, but strangely the errors only ever go one-way 😉 I’m sorry, I can’t believe in a system that can only find errors that go one-way. Also it is my understanding that adjustments of surface temperatures have been done which decreases past temperatures. Beyond the obvious question and reaction – ‘wtf?’, this has the effect of increasing temperature rise over the past while not getting out of line with the satellites too much. Ya … adjust the period before satellites downward … hmmm ok.
Maybe there has been warming, maybe there hasn’t. I’m skeptical because I can’t believe in data that is only being adjusted one-way and doesn’t take into account UHI (Anthony’s own passion for surface station evaluation shows UHI is real and has a huge effect, beyond any reasonably doubt) Given that, finding room to fit a measly 0.7C temperature rise through these kinds of error mechanisms would seem rather easy.
On a completely different note and something I have been thinking about … how are temperatures averaged? I believe that it is a simple average … which is obviously plain wrong. Temperature average should be the 4th root of the average of the 4th power of temperature, because outward thermal radiation is proportional to the 4th power of temperature. NOT doing it this way means that if temperatures around the world became flatter (i.e. distributed more towards the poles and reduced at the equator) then this would ‘look’ like an increase in average temperature when it is really just a change in the distribution of energy and the total energy remains unchanged. Not too even get into taking specific heat values into account and so on. How can we trust a system to come up with an average temperature that doesn’t know how to properly average temperature?
Antony,
I’m a reader of your blog, and I’ve found this news today on a Italian meteorological site, probably you already aware of that, anyway it says:
“Cosmic rays and clouds, Europe will finance a research project to discover causes of global warming.”
2.3M euro will be spent to research correlation between solar radiation, clouds and global temperature change.
(i.e : EU start to have doubt on the famous AGW, a start to give credit to other theory)
You can find the Italian article here : http://meteolive.leonardo.it/meteolive-notizia-25185-raggi_cosmici_e_nuvole,_lue_finanzia_il_progetto_di_ricerca_per_scoprire_le_cause_del_global_warming.html
It’s in Italian, if you need a complete translation let me know
Regards
Paolo
Ian,
Thanks for your detailed response
As for the satellite ‘adjustment’ there is no mystery to this – one of the corrections in the UAH analysis (related to the drift in crossing times at the equator) had the wrong sign and this is acknowledged by Christy / Spencer.
I still find it hard to believe that 3 independent groups (GISS, HADcru and NSDC) would end up with temperature reconstructions that are essentially identical, coupled with the work that John V did at climate audit reconstructing the US temperature from the only good stations using a totally different method from GISS again should end up essentially identical.
Again – from my woodsfortrees plot, rss, hadcru and giss are showing just a shade under 0.5 deg C change in the satellite era – most of the change has happened in the satellite era
Totally take the point that a lot of this is finding a signal in noisy data.
As for adjustments – I can see that when a theory disagrees with measurements they will try and find a source for that disagreement, whether that be a change to the model (eg Hansen’s early GCM s ended up with a climate sensitivity of 4 Deg C – the current GISS model, I think, has a climate sensitivity of 2.7 Deg C) or checking if there is something wrong with the observations (e.g. the ocean cooling that was not cooling)