This is one of those times I’m really glad WiFi has been installed on passenger aircraft. After reviewing this paper at Nic Lewis’ home prior to that extraordinary meeting with climate scientists I mentioned, and expecting a leisurely writeup in about a week, Nic sends me this email which I get on the plane:
Anthony, Climate Dynamics has released my paper nearly a week earlier than they said!!
This is a significant paper. As I once read on Climate Audit:
This will set the cat amongst the pigeons
Here is the paper at Climate Dynamics: http://link.springer.com/article/10.1007/s00382-014-2342-y
The implications for climate sensitivity of AR5 forcing and heat uptake estimates
Abstract
Energy budget estimates of equilibrium climate sensitivity (ECS) and transient climate response (TCR) are derived using the comprehensive 1750–2011 time series and the uncertainty ranges for forcing components provided in the Intergovernmental Panel on Climate Change Fifth Assessment Working Group I Report, along with its estimates of heat accumulation in the climate system. The resulting estimates are less dependent on global climate models and allow more realistically for forcing uncertainties than similar estimates based on forcings diagnosed from simulations by such models. Base and final periods are selected that have well matched volcanic activity and influence from internal variability. Using 1859–1882 for the base period and 1995–2011 for the final period, thus avoiding major volcanic activity, median estimates are derived for ECS of 1.64 K and for TCR of 1.33 K. ECS 17–83 and 5–95 % uncertainty ranges are 1.25–2.45 and 1.05–4.05 K; the corresponding TCR ranges are 1.05–1.80 and 0.90–2.50 K. Results using alternative well-matched base and final periods provide similar best estimates but give wider uncertainty ranges, principally reflecting smaller changes in average forcing. Uncertainty in aerosol forcing is the dominant contribution to the ECS and TCR uncertainty ranges.
A PDF file of a reformatted version of the final revised manuscript titled ‘The implications for climate sensitivity of AR5 forcing and heat uptake estimates’, with minor editing corrections, is available here: Lewis&Curry_AR5 energy budget climate sensitivity_Clim Dyn2014_accepted (reformatted, edited). This work was accepted for publication by Climate Dynamics on 13 September 2014.
A compressed zip file containing data and computer code that will generate the results in the paper is available here: AR5-EB-LewisCurry-ClimDyn-2342
Nic is preparing a discussion about the paper to post at Climate Audit, I’ll add it when it is ready – Anthony (somewhere over Canada)
UPDATE: The CA post is up at http://climateaudit.org/2014/09/24/the-implications-for-climate-sensitivity-of-ar5-forcing-and-heat-uptake-estimates-2/
EXCERPT:
When the Lewis & Crok report “A Sensitive Matter” about climate sensitivity in the IPCC Fifth Assessment Working Group 1 report (AR5) was published by the GWPF in March, various people criticised it for not being peer-reviewed. But peer review is for research papers, not for lengthy, wide-ranging review reports. The Lewis & Crok report placed considerable weight on energy budget sensitivity estimates based on the carefully considered AR5 forcing and heat uptake data, but those had been published too recently for any peer reviewed sensitivity estimates based on them to exist.
I am very pleased to say that the position has now changed. Lewis N and Curry J A: The implications for climate sensitivity of AR5 forcing and heat uptake estimates, Climate Dynamics (2014), has just been published, here. A non-paywalled version of the paper is available here, along with data and code. The paper’s results show the best (median) estimates and ‘likely’ (17–83% probability) ranges for equilibrium/effective climate sensitivity (ECS) and transient climate response (TCR) given in the Lewis & Crok report to have been slightly on the high side.
Our paper derives ECS and TCR estimates using the AR5 forcing and heat uptake estimates and uncertainty ranges. The analysis uses a global energy budget model that links ECS and TCR to changes in global mean surface temperature (GMST), radiative forcing and the rate of ocean etc. heat uptake between a base and a final period. The resulting estimates are less dependent on global climate models and allow more realistically for forcing uncertainties than similar estimates, such as those from the Otto et al (2013) paper.
Base and final periods were selected that have well matched volcanic activity and influence from internal variability, and reasonable agreement between ocean heat content datasets. The preferred pairing is 1859–1882 with 1995–2011, the longest early and late periods free of significant volcanic activity, which provide the largest change in forcing and hence the narrowest uncertainty ranges.
Table 1 gives the ECS and TCR estimates for the four base period – final period combinations used.
Table 1: Best estimates are medians (50% probability points). Ranges are to the nearest 0.05°C
AR5 does not give a 95% bound for ECS, but its 90% bound of 6°C is double that of 3.0°C for our study, based on the preferred 1859–1882 and 1995–2011 periods.
Considerable care was taken to allow for all relevant uncertainties. One reviewer applauded “the very thorough analysis that has been done and the attempt at clearly and carefully accounting for uncertainties”, whilst another commented that the paper provides “a state of the art update of the energy balance estimates including a comprehensive treatment of the AR5 data and assessments”.
Full report here: http://climateaudit.org/2014/09/24/the-implications-for-climate-sensitivity-of-ar5-forcing-and-heat-uptake-estimates-2/
UPDATE2: Judith Curry weighs in. More details on the paper at
http://judithcurry.com/2014/09/24/lewis-and-curry-climate-sensitivity-uncertainty/
So climate is always changing; even now they all scream at us.
So just when will we reach climate equilibrium, that this paper mentions??
Earth rotates, therefore weather is never in equilibrium. Climate is the integral of weather.
Ergo, climate is never in equilibrium.
Any system in thermal equilibrium, must be isothermal. That’s a three dollar word for ” all at the same Temperature.”
Take a look at the recent post at unrealclimate. Its about methane and come to think of it I’ve seen quite a number of recent articles regarding the catastrophic consequences when methane gets released from thawing tundra or from clathrates at the bottom of the sea.
I predict that what we are seeing is a pivot away from the dependence of climate catastrophe’s on the concentration of CO2. Methane has far greater “greenhouse” potential than co2 and the increase of 1-2C will be the “trigger” for huge releases in methane that will be the tipping point for large increases in temperature not achievable by co2 alone.
Does this paper take into account all the heat that the Koch brothers have been hiding deep in the ocean?
We should have a poll on what value of ECS people think is correct.
Exactly. And whatever the majority of people think will be “settled science.” Wasn’t “science” a by-product of the enlightenment whose purpose was to move beyond religion and philosophy as a theory of knowledge by demonstrating through empirical evidence and observations facts that could stand on their own? I see very little “science” in the current state of climatology. I commend the efforts of this study to use the warmists own facts against their stated conclusions, but I agree with others in this thread that the study does little to advance the actual science.
rgbatduke – re: press coverage – not sure you are right. David Rose of the UK’s Daily Mail was at Nic Lewis’s dinner party with Anthony, plus David Whitehouse of GWPF. The Australian carried Steve Koonin’s WSJ piece too. I think this will get some traction.
“The preferred pairing is 1859–1882 with 1995–2011, the longest early and late periods free of significant volcanic activity, which provide the largest change in forcing and hence the narrowest uncertainty ranges.”
I understand the power of using the IPCC’s own data to chop the estimates, but I’m wondering what those estimates would be if we hadn’t added on at least 0.3-0.5C to the 100 year warming by pushing down the temps of the first half and jacking up those of the second half. Yeah, I know all about TOBS etc and the rationale, but definitely every 0.1C that could be added (or subtracted from the early part) without setting off alarm bells, to tilt the temperature curve upwards WOULD be done. You can be sure every metric that supports the meme would be pushed in the desired direction. It is human nature. Indeed, in the corporate sphere, anti-trust laws ARE violated if two or more companies had an opportunity to collude!!! If the not-so-big-these-days 3 auto makers’ presidents were seen together having a drink on their holidays in Palm Springs, or sharing a taxi, or even being in the same hotel, or on the golf course, you wouldn’t need any tape recording. They would be automatically guilty of unfair trade practices. This is equally true for the ‘clime syndicate’ (thanks Mark Steyn) who depend on cash flow from gov. Too bad anti-trust can’t be invoked for the syndicate – they wouldn’t even deign to meet in such a shabby place as Palm Springs.
Without wading through the paper, does this imply that we now sufficiently understand atmospheric processes such that it is no longer a “travesty” that we can’t explain the lack of warming over the past 2 decades, despite more than 1/3 of all man’s CO2 being pumped into the atmosphere over that period?
first, read the paper. It is free, so no excuses.
Second, not it does not answer the question you pose. It only provides one partial rational. It very specifically tries to eliminate natural variability to the extent it can.
Congratulations, Dr. Stokes and Dr, Curry.
This looks like a very solid paper, once again pointing to lower climate sensitivity.
Sorry, I meant Dr. Lewis.
Stokes would be having a stroke if he wrote anything that wasn’t alarmist.
mothcatcher
September 24, 2014 at 1:37 pm
“Maybe Mosh amuses himself better than he amuses other readers, but his point about the ‘crazy denial’ commenters should be repeatedly made. Some of it is pretty lightweight/frothy and yes, it does devalue an excellent blog in the eyes of the outside world.”
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Gottya, less is more.
Must not upset the “outside world” view.
I can get even frothier if you want, just say go.
For anyone who missed it, read this comment:
Rud Istvan September 24, 2014 at 12:42 pm
in response to this comment:
mpainter September 24, 2014 at 9:43 am
Lewis and Curry use IPCC’s own data, assumptions and estimates to shoot down the AR5 conclusions. As Mr Istvan says: “A falsification as powerful as the pause, using different means.” The name of this article also gives you a great big hint: “…lowers the range of climate sensitivity using data from IPCC AR5”.
Interesting.
I merely used this for the same point. Anyone seen this before or know of a newer version?
http://cosmoscon.files.wordpress.com/2011/12/co2-vs-temp.jpg
I guess grabbing the tables off woodfortrees and displaying them myself would do the job.
As goes climate sensitivity, It seems basically linear.
http://www.nebulousresearch.org/other/archibald/archibald-33.jpg
The steepness of the linearity is erm, Lets say flatlined.
A hockey stick! (inverted)
Congratulations to both Nic Lewis & Judith Curry on this landmark publication. Wow. Hot stuff!
Steven E. Koonin (https://en.wikipedia.org/wiki/Steven_E._Koonin) remarked, in his recent WSJ essay
http://online.wsj.com/articles/climate-science-is-not-settled-1411143565 “Climate Science Is Not Settled,” that
“Today’s best estimate of the [climate] sensitivity (between 2.7 degrees Fahrenheit and 8.1 degrees Fahrenheit) is no different, and no more certain, than it was 30 years ago. And this is despite an heroic research effort costing billions of dollars.”
Good to see Lewis & Curry resolving this conundrum, and on a considerably lower budget!
1. Climate sensitivity is not a constant across all climactic states. It is the sum total of numerous forcings and feedback mechanisms, which themselves are not constant across climactic states (e.g. ice albedo feedback.) It should be no surprise that climate sensitivity estimates derived using recent observations should differ from those derived from paleo data (e.g. the last glacial retreat.)
2. Antarctic ice extent (particularly it’s anomalous expansion despite warming temperatures) may explain the difference between model estimates of climate sensitivity and recent observations. I don’t believe any models predicted that warming would result in expanding ice coverage and therefore negative ice albedo feedback for the southern hemisphere.
They were very good OTOH at predicting positive albedo feedback for decreasing arctic ice.
BTW it is not a negative feedback. A positive feedback amplifies its cause; a negative feedback dampens it.
So, the feedback of growing sea ice is a positive feedback even when it works to reduce temperatures. It works in both directions in an amplifying, i.e. “positive” manner, in feedback-lingo.
DirkH is right. Looking at the interaction between negative and positive feedbacks is the only [way] to understand a dissipative complex nonlinear system such as climate. If we lose the ability to even correctly define and talk about positive and negative feedback then any remaining chance of understanding climate goes out of the window. This is instead the beginning of a retreat from symbolic language and the unevolution of sentience.
ook ook
[? One of those is definitely misspelled, but I can’t figure out which one. .mod]
OK, so try to make a “clear and concise” “feedback” term for the following:
Increasing Arctic sea ice loss during a time of assumed Arctic warming increases heat loss and cools the planet.
Increasing Antarctic sea ice gain during a period of measured cooling Antarctic air temperatures cools the planet.
There is a suggestion that the IPCC could have done this had they wanted to. Any idea who didn’t want to?
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all of them?
Real simple. The lead authors. Look again at the official published WG1 excuse for not providing an AR5 best estimate. Something about reality not agreeing with the CMIP5 models they relied on.
HUGE.
But they’re still 95% confident in whatever they are saying, or not saying:) Or is it now 97%?
Thanks, Rud.
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Estimates of climate sensitivity: “are derived using the … uncertainty ranges for forcing components provided in [AR5].”
AR5’s forcing estimates assume that no mechanism of “solar amplification” is at work and the error bars on the AR5 solar forcing estimates do not include any estimate of the possibility that other solar forcings besides TSI could be at work, despite the overwhelming evidence for SOME solar driver of climate more powerful than TSI.
Nic and Judith acknowledge this omission at the bottom of page 6 of their PDF:
Their exercise proceeds in accordance with the IPCCs assumption that most late 20th century warming was caused by CO2 and notes how, even on this assumption, the lack of 21st century warming causes the estimated warming effect of CO2 (in the form of the estimated climate sensitivity) to be reduced considerably.
If it turns out that some powerful non-TSI solar driver is in play and that 20th century warming was largely caused by the high level of solar activity from 1920-2000 (Usoskin’s “grand maximum” dating), then the warming that is left to attribute to CO2 becomes that much smaller still. It is very much in prospect that the actual climate sensitivity is substantially less than one (negative feedback).
Great, so it turns out there was no problem after all. We can all now go home. Thanks for the great job Anthony. Last person to exist the web site please turn off the server.
I can’t tell if you are kidding or not.
It would however have been a great waste of time, money, and scientific talent.
Except for the data collected.
Which is not to say another scare story won’t be coming down the pipeline.
Might wanna keep the server warmed up 🙂
ECS with the highest probability in the plot is about 1.25 deg. Perhaps even lower with a proper temperature data set.
They still haven’t taken solar cycles into consideration.
I said it was 1.25 degrees over 5 years ago
markstoval
September 24, 2014 at 11:40 am
“To be “cured” against one’s will and cured of states which we may not regard as disease is to be put on a level of those who have not yet reached the age of reason or those who never will; to be classed with infants, imbeciles, and domestic animals.” ― C.S. Lewis
The ideo_logues understand this well. That is why first they enter professions and seek office in institutions that will dumb down the populace, even (or especially) in the lefty progression of university teaching such that they will make infants, imbeciles and domestic animals out of them. They take over NGOs, the environmental portfolio because these already are full of zealots and and an endless supply of ready-to-serve useful idjits.
This fight is far from over. But nature will eventually settle the debate one way or another no matter how many times politicians and climate scientists may suggest that the debate is over.
However, this paper does show the problems facing AR6.
If there is no warming between now and 2018, and if the data comprising the second period is extended out to 2018 rather than being cut at 2011, and if there are no volcanos through to 2018, AR6 will have to fess up that climate sensitivity is far lower than previously suggested.
Couple that problem to the fact that. if there is no warming between now and 2018, all models will be out of the 95% confidence band, and AR6 is looking like it will be a very difficult report to write.
The 2015 climate conference really might be the last gasp because the potents looking ahead are not good from those in the warmist camp.
Richard, never mind AR6. It is Paris 2015, and “OBummer” that is the present political fight. Please enlist.
No, you are missing the real point here. The missing heat has gone even deeper into the depths of the oceans than we had at first thought.
I do not believe that the IPCC will ever climb down from its position that climate model projections are correct. In my view this organization is in the grip of persons who are dedicated to a cause, not to scientific verity. It will only change when such persons are removed from their positions of influence.
OT: I have improved the photo of the Bath-dinner and would like to email it to Anthony/WUWT. Is there an email address that I can use for this? David Greene. My email address: 301parkave at gmail dot com
FYI for those wanting to run Lewis’ code – found a minor problem.
Paths weren’t coded properly / were hardcoded with Lewis’ PC’s directory structure.
Lines 217 & 218 should be replaced with:
AR5hc= matrix(scan(paste(path.heat, ‘/heat_ascii_v6.txt’, sep=””), skip=1, quiet=TRUE), ncol=13, byrow=TRUE)
colnames(AR5hc)= scan(paste(path.heat, ‘/heat_ascii_v6.txt’, sep=””), what=’character’, nlines=1)
First of all congratulations to Nic and Judy for getting this (C)AGW busting paper into the literature.
Now, as others have mentioned this paper assumes all warming is caused by CO2. Several analysis I’ve seen limit the CO2 warming to a maximum of 60% (probably less). That would reduce the real TCR to 1.33*.6 = .8C.
This would indicate either negative feed-backs are in place or there are some errors in the way CO2 warming is specified in the literature. Probably both.
I recall that within the last few months Dr. Curry on her blog suggested that about 50% of the warming appeared to be due to natural variation (predominantly ocean cyclyes).
When you take that into account, and when you consider the implication of the many adjustments that have been made to the temperature record that have made the past coler and the present warmer, when you account for station drop outs, and pollution by UHI, it is probably that the TCR is very much less than the figure you suggest.
I am with Brian H, that when all is done and dusted, say in 20 years time, it will probably be seen to be approximately 0 degC, or at any rate, so small that the signal cannot be measured using our best measuring equipment. It will probably all be seen to be lost in the noise of natural variability.
Come on, all you do is stir the pot here, now you feel put upon ?
I thought you had a funny story.