Yesterday we talked about the new paper from Nic Lewis, now Troy Masters has a new paper in press at Climate Dynamics here.
Observational estimate of climate sensitivity from changes in the rate of ocean heat uptake and comparison to CMIP5 models
Unfortunately, Springerlink wants $39.95 for the privilege of reading it, so all I can do is to provide the abstract. From his blog however, Troy does show figure 5 of the paper:
Abstract. Climate sensitivity is estimated based on 0–2,000 m ocean heat content and surface temperature observations from the second half of the 20th century and first decade of the 21st century, using a simple energy balance model and the change in the rate of ocean heat uptake to determine the radiative restoration strength over this time period. The relationship between this 30–50 year radiative restoration strength and longer term effective sensitivity is investigated using an ensemble of 32 model configurations from the Coupled Model Intercomparison Project phase 5 (CMIP5), suggesting a strong correlation between the two. The mean radiative restoration strength over this period for the CMIP5 members examined is 1.16 Wm−2K−1, compared to 2.05 Wm−2K−1from the observations. This suggests that temperature in these CMIP5 models may be too sensitive to perturbations in radiative forcing, although this depends on the actual magnitude of the anthropogenic aerosol forcing in the modern period. The potential change in the radiative restoration strength over longer timescales is also considered, resulting in a likely (67 %) range of 1.5–2.9 K for equilibrium climate sensitivity, and a 90 % confidence interval of 1.2–5.1 K.
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Compared to Dr. Roy Spencer’s post about models -vs- reality…
…it looks more and more as if climate sensitivity is on the lower end of the scale, rather than the high end such as was claimed recently at RealClimate by Fasullo and Trenberth which was 4°C for a doubling of CO2.
And there’s yet ANOTHER paper arguing for lower climate sensitivity. See it here
Causes of the global warming observed from the 19th century
M.J. Ring, D. Lindner, E.F. Cross, R.E. Schlesinger
Abstract. Measurements show that the Earth’s global-average near-surface temperature has increased by about 0.8℃ since the 19th century. It is critically important to determine whether this global warming is due to natural causes, as contended by climate contrarians, or by human activities, as argued by the Intergovernmental Panel on Climate Change. This study updates our earlier calculations which showed that the observed global warming was predominantly human-caused. Two independent methods are used to analyze the temperature measurements: Singular Spectrum Analysis and Climate Model Simulation. The concurrence of the results of the two methods, each using 13 additional years of temperature measurements from 1998 through 2010, shows that it is humanity, not nature, that has increased the Earth’s global temperature since the 19th century. Humanity is also responsible for the most recent period of warming from 1976 to 2010. Internal climate variability is primarily responsible for the early 20th century warming from 1904 to 1944 and the subsequent cooling from 1944 to 1976. It is also found that the equilibrium climate sensitivity is on the low side of the range given in the IPCC Fourth Assessment Report.
From the paper:
Additionally, our estimates of climate sensitivity using our SCM and the four instrumental temperature records range from about 1.5 ̊C to 2.0 ̊C. These are on the low end of the estimates in the IPCC’s Fourth Assessment Report. So, while we find that most of the observed warming is due to human emissions of LLGHGs, future warming based on these estimations will grow more slowly compared to that under the IPCC’s “likely” range of climate sensitivity, from 2.0 ̊C to 4.5 ̊C. This makes it more likely that mitigation of human emissions will be able to hold the global temperature increase since pre-industrial time below 2 ̊C, as agreed by the Conference of the Parties of the United Nations Framework Convention on Climate Change in Cancun.
Dr. Judith Curry sums it up pretty well:
In weighing the new evidence, especially improvements in the methodology of sensitivity analysis, it is becoming increasing difficult not to downgrade the estimates of climate sensitivity.
All this blows the laughable Skeptical Science claim Climate Sensitivity Single Study Syndrome, Nic Lewis Edition out of the water. Dana should quit while he’s ahead, because his arguments aren’t convincing.
h/t to Mosher
Related articles
- A Comparison Of The Earth’s Climate Sensitivity To Changes In The Nature Of The Initial Forcing (wattsupwiththat.com)
I can think we can safely say that a consensus of recent papers – probably 97% of them in fact – points to a low sensitivity… .
The IPCC’s suggestion, that climate sensitivity is most likely to be in the range 2.0 to 4.5°C , is shown to be barely supportable and then only by favoring computer simulations of the climate over empirical measurements. Yes confusion reigns, but is that not part of the plan? If it had not been for the internet, the Alarmists plan would in a large part already been implemented. If that would have happened we now would all be living in FUBAR land.
So in regards to climate sensitivity and the Alarmist screaming’s of massive positive feedback. It seems to me to throw lesson one of the scientific method out of the classroom window. And I really do mean lesson one: “ In general, we look for a new law by the following process: First we guess it; then we compute the consequences of the guess to see what would be implied if this law that we guessed is right; then we compare the result of the computation to nature, with experiment or experience, compare it directly with observation, to see if it works. If it disagrees with experiment, it is wrong. In that simple statement is the key to science. It does not make any difference how beautiful your guess is, it does not make any difference how smart you are, who made the guess, or what his name is — if it disagrees with experiment, it is wrong.” Richard Feynman”.
So an examination suggests that the values of climate sensitivity used in the PAGE model are highly debatable. But of course it’s actually even worse than that (it usually is). Close followers of the climate debate will recall Nic Lewis’s guest post at Prof Curry’s blog last year, in which he noted that the “Forster and Gregory” values in the IPCC graph were not the values that were implicit in Forster and Gregory’s published results – the IPCC had notoriously chosen to restate the findings in a way that gave a radically higher estimate of climate sensitivity. See: http://judithcurry.com/2011/07/05/the-ipccs-alteration-of-forster-gregorys-model-independent-climate-sensitivity-results/
Love this: “The IPCC took eight studies on climate sensitivity of which one (Forster/Gregory 06) was the only study based purely on observational evidence, with no dependence on any climate model simulations threw said study in their voodoo math machines and basically came up with 2 x the result. It then put the study up in the graph with the other studies and basically pulled the “Mikes nature trick/hide the decline” game.”.
On another study: http://www.agu.org/pubs/crossref/2006/2005GL023977.shtml “Estimated PDFs of climate system properties including natural and anthropogenic forcings.” Nicholas Lewis has been trying for over a year and a half, without success, to try and obtain from Dr Forest the data used in Forest 2006. However, he has been able to obtain without any difficulty the data used in two related studies that were stated to be based on the Forest 2006 data. It appears that Dr Forest only provided pre-processed data for use in those studies, which is understandable as the raw model dataset is very large. Unfortunately, Dr Forest reports that the raw model data is now lost. Yes LOST, the dog ate my data! Worse, the sets of pre-processed model data that he provided for use in the two related studies, while both apparently deriving from the same set of model simulation runs, were very different. Talking of dogs, seems my vet keeps better a record of my dog’s health that Dr Forrest can.
The global warming scare has fizzled like a wet fire cracker. The sun has entered a new quiet phase, and average global temperatures have been stable for 16 years. Wasteful and ridiculous Climate conferences in Doha and elsewhere have achieved nothing except hot air and Green bollocks. Kyoto has become a sick joke and is now a footnote at the bottom of the page in history. Countries that agreed to climate stabilization policies have failed miserably and now are retreating from that untenable position. The general public has really had enough of the scaremongering and have more important things in their lives. In short most people just laugh as CACW is now just a very expensive bad joke.
Looks like it’s about 1-1.5C for a doubling….
To the layman that spaghetti graph is quite clear: the 1998 spike wasn’t “consistent with models”, it was just a blip, and the models are all over the place anyway.
I prefer the caveman approach. I am a top-down sort of a person, having designed a number of non-climate simulations. The problem with the models is that they try to do the Russian Front using a man-to-man approach rather than an Army Group-to-Front approach, and that results in huge bottom-up divergence error.
Stipulating that temperatures rose 0.7C over the last century (and I think it is significantly lower), that comes after natural forcings (e.g., most of the warming pre-1950) and non-CO2 anthropogenic effects (such as soot), that comes after a CO2 increase of 40%. Including feedbacks.
Given the gross data and effects, I find it hard to conclude that sensitivity is as much as double the 0.7C figure, for a doubling of CO2. Probably more in the range of 1.0 or so: Arrhenius effect alone, with a net-neutral feedback.
I see very little analysis based on this basic approach in the literature. And it seems to me that this is the approach to start with.
So when the EU and UN leaders were calling for drastic and economy destroying action to keep temperature rise to a minimum of 2C by 2100 as their goal, we are now seeing that taking NO ACTION WHATSOEVER, will still see us reach and do even better than their goal.
Can we stop all these expensive, pointless, damaging, industry destroying, elderly killing “green” taxes now, please???
in reply to jb frodsham above…
You said, “Countries that agreed to climate stabilization policies have failed miserably and now are retreating from that untenable position. “
I wish that were true. The UK passed a climate change act which will destroy our economy and leave tens of thousands of elderly, infirm and the poorest people dead from hypothermia and the Government in the UK is determined to implement it in full. The UK government is, tragically, meeting it’s obligation to reduce CO2.
We in the UK desperately need bring lots of pressure to bare on the MPs to force them to repeal the futile, damaging and expensive climate change act.
The climate change act is an exercise in cruel futility, as even if we in the UK stopped ALL our CO2 emissions, China, Brazil and India will all massively off-set our losses in emissions and our outsourcing of emissions may even see our indirect (outsourced) emissions increase in other parts of the world. Our Climate Change Act will not reduce global temperatures at all, they will not reduce sea levels, or protect a single glacier, or save a single polar bear, or prevent a single flood, or drought. This Act is futile, completely and utterly futile.
Now on top of the fact that our emissions will be offset, thus failing to reduce global CO2 emissions at all, we are becoming increasingly aware, that the climate’s sensitivity to CO2 is nowhere near as great as the threat that the alarmists perceived it to be, so again, more and more reason to abandon the industry destroying and elderly killing CO2 reduction targets in the UK.
Sadly, our demented leaders seem obsessed to have the CO2 targets as one of the very very few things that they are not prepared to U turn on. In spite of more and more evidence clearly showing that they should.
How difficult would it be to just dial in a lower sensitivity and run the models? Has anyone ever done that, or are they afraid the result would be closer to reality?
So, according to this paper, humanity is responsible for the period of warming from 1976 to 2010
And how do they know….?
Empirical evidence?
You wish…….!
Climate Model Simulation.
Sigh……….
That Skeptical ‘science’ article calls it “single study syndrome” then links to another study with more or less the same outcome. Is this deliberate self parody?
There is also a paper by Bjornbom that deduces that a doubling of CO2 will lead to a rise of 0.18 C at the surface.
Here is the abstract:
Estimation of the climate feedback parameter by using radiative fluxes from CERES EBAF
P. Björnbom
KTH Royal Institute of Technology, c/o Pehr Björnbom, Kometvägen 1, 18333 Täby, Sweden
Abstract. Top-of-the-Atmosphere (TOA) net radiative flux anomalies from Clouds and Earth’s Radiant Energy Systems (CERES) Energy Balanced and Filled (EBAF) and surface air temperature anomalies from HadCRUT3 were compared for the time interval September 2000–May 2011. In a phase plane plot with the radiative flux anomalies lagging the temperature anomalies with 7 months the phase plane curve approached straight lines during about an eight months long period at the beginning and a five year period at the end of the interval. Both of those periods, but more clearly the latter one, could be connected to the occurrence of distinct El Niño Southern Oscillation (ENSO) episodes. This result is explained by using a hypothesis stating that non-radiative forcing connected to the ENSO is dominating the temperature changes during those two periods and that there is a lag between the temperature change and the radiative flux feedback. According to the hypothesis the slopes of the straight lines equal the value of the climate feedback parameter. By linear regression based on the mentioned five year period the value of the climate feedback parameter was estimated to 5.5 ± 0.6 W m−2 K−1 (± two standard errors).
See http://hockeyschtick.blogspot.com/2013/01/new-paper-confirms-findings-of-lindzen.html
“humanity is also responsible for the warming from 1976 – 2010”
is that according to his (GIGO) model ?
or reality and if so, who’s reality ?
Even the low sensitivity versions look at the atmospheric temperature rise in the 1970 -1998, and assume the flat level for 1998-2013 as just a pause in rise. Ocean data is obviously not reliable before about 2003, so I would not place any emphasis in that. If the atmospheric and ocean temperature levels continues nearly flat to downward going forward, any claimed sensitivity greater than zero would have to explain why there is no significant rise.
…Troy Masters has a new paper in press at Climate Dynamics…
How many journals sprang up to take advantage of, er, spread the sanctified gospel about, er, provide additional outlets for the needed dissemination of information concerning, the climate change crisis?
How many journals have been become irredeemable following their endless shameless extremism, er, partisan promotion of politically-expedient positions, er, questionable editorial practices yielding apparent bias, concerning their believed certainty of CAGW?
With the Climate Change Creature vanishing in the daylight,
The assorted “Green technologies” revealed as a handful of bubbles left to burst and drain away as consumers rouse themselves and get out of the cold fiscal bath,
The “impending unwavering doom” revealed as possible discomfort after several hundreds of years of not taking advantage of the coming advancing technology with inherent “carbon emissions” reductions,
Whatever will happen to all these unneeded and largely-unread climate-focused journals?
Douglas Hoyt says:
You are just repeating a false statement made by HockeySchtick on his website. He used an incorrect method of converting from the finding that the feedback parameter is 5.5 ± 0.6 W m−2 K−1 to what the sensitivity to doubling CO2 is, apparently because he doesn’t understand what people mean by “top of the atmosphere”. The correct conversion would say that it predicts a surface warming of ~0.7 C per CO2 doubling.
Furthermore, as noted by one of the online reviewers ( http://www.earth-syst-dynam-discuss.net/4/C161/2013/esdd-4-C161-2013.pdf ), the author of the paper has made no attempt to validate his method of computing the feedback parameter. Hence, this is a result using a method that is completely untested. You just have to take it on faith that this is a valid method for assessing the feedback parameter and climate sensitivity…Hardly the way one would expect a real skeptic to proceed.
Stefan (April 18, 2013 at 3:20 am) “To the layman that spaghetti graph is quite clear: the 1998 spike wasn’t “consistent with models”, it was just a blip”
Stefan, I agree. The modelers made a number of conclusions in the early 2000’s based on that blip and 1980s/90’s warming that are now proving wrong: high sensitivity, more El Ninos (although that was still under debate), less blocking (stronger, more northerly polar jet), etc. Their fundamental mistake was to believe that the slight warming from CO2 would create new weather regimes resulting in positive feedback. To the contrary, weather drives fluctuations an order of magnitude (more in the short run) greater than warming from increased CO2.
Now various alarmists (e.g. Romm) without realizing the ramifications are claiming that warming from CO2 is creating new weather regimes which are in fact negative feedback (stronger storms, droughts, blocking patterns, etc) If we are to believe those claims of weather doom then we must also accept lower sensitivity. On the SkepSci thread a couple years ago, they called this my theory of mutually exclusive catastrophe. Their reply was basically that it wasn’t true or that we are doomed whether we have storms or strong warming which melts Greenland’s ice.
Friends:
I write to ask a genuine question. This post is NOT ‘knocking copy’.
I argue that climate sensitivity is low and, therefore, if I were being prejudiced then I would be supporting this study by Troy Masters.
But my question is
Does anybody think the paper by Troy Masters has any credibility and, if so, why?
The reason for my question is simple and is as follows.
As recently as yesterday there was a article about ocean heat uptake by Bob Tisdale posted on WUWT. It is at
http://wattsupwiththat.com/2013/04/17/a-different-perspective-on-trenberths-missing-heat-the-warming-of-the-global-oceans-0-to-2000-meters-in-deg-c/
and it can be summarised by this quotation from it.
Of course, we cannot “sense such a small change” and it is a construct of assumptions.
Today we have a report of this study by Troy Masters which says
So, the paper by Masters derives a value for climate sensitivity based on assumptions. And I fail to understand how anybody can confuse such a derivation with science.
Richard
These “lower estimates” are just absurd. They are like the gambler who having tossed a coin three times and getting it right, then says for the forth when they get it wrong: “my ability to predict isn’t quite as high as I thought”.
In other words, we will see natural climate variation continue to be the main factor changing the global temperature. And if it goes down … they will continue to adjust their models downward, and if it goes up … they will adjust their models upward.
Without ever contemplating the reality that they cannot predict the climate at all.
Climate sensitivity is just a jazzed up climate researcher’s name for ESP
These papers are important small steps in the right direction. If you are a climate scientist today and you want to question the alarmist orthodoxy, you are taking big chances with your career. So the alternative is to produce numbers that are just a little bit lower, but not low enough to allow the team to declare you a heretic. Then, as the number of published papers pile up on the lower end of the sensitivity range, it allows others to take it even a little further. In the long run the guys that are being careful will arrive at the same place as people like Spencer and Lindzen.
Now, just for a moment try to imagine that the UAH and RSS lines in Roy’s post are ABOVE all the models instead of below them.
Raise your hand if you think Hansen, Trenberth, etc., would be defending the models, as opposed to shrieking at the top of their lungs “THE MODELS WERE WRONG, IT’S EVEN WORSE THAN WE THOUGHT!!”
Anyone? Anyone? Bueller?
Abstract. Measurements show that the Earth’s global-average near-surface temperature has increased by about 0.8℃ since the 19th century.
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So it is a kind of mystery, because the global average has gone up by 0.8 deg C already between 1910-1945:
http://www.woodfortrees.org/plot/hadcrut3vgl/from:1910/to:1945
At the same time, CO2 went up by tenth, compared to modern, post1-1975 warming when temperature went up by mere half, so CO2 has definitively a cooling effect or something 😮
http://www.woodfortrees.org/plot/rss/from:1975/to:2004
None of the models replicates 1910-1945 warming, maybe some 0.1 deg C. Even with overblown positive feed backs and thick radiation arrows, one can not get 0.8 deg C warming from humans in the early part of 20th century!! Zero hypothesis is, that the natural warming in 1910-45 has repeated itself again in 1975-2005 period, with natural cooling in between and since 200X again.
If the climate models were truly concerned with calculating CO2 sensitivity, then CO2 sensitivity would be one of the outputs of the models. The models would use observed temperature as an input and spit out climate sensitivity as an output.
However, that is not what has been done. Climate models use an assumed climate sensitivity as an input and spit out temperature as an output. The divergence between the models and observations tells us that the models have wrong assumptions. However, it tells us very little about what the true sensitivity should be because of the non-linear aspects of climate.
what was built:
climate model (assumed sensitivity co2) = predicted temperature
what the customer ordered:
inverse climate model (observed temperature) = true sensitivity co2
Unfortunately, Springerlink wants $39.95 for the privilege of reading it
It’s hilarious how things like this are real stumbling blocks for skeptics, while the AGWers claim we’re getting billions from oil companies, Koch brothers, etc.
I bet Mann, Gavin, Hansen, Jones, etc don’t even have to submit a receipt for something like this to have it paid for by us (the taxpayers).
Climate sensitivity is not a constant. Trying to find a fixed value for a variable is a fool’s errand. There are many factors in our climate system that will lead to different sensitivities at different times. I think this is evident as people are now finding different numbers than they did when the Earth was warming instead of cooling.
Sensitivity probably takes the form … f(x,y,z,…) … where we know far too little about x,y,z,…
jb frodsham says:
”If it had not been for the internet, the Alarmists plan would in a large part already been implemented.”
And the current pause could be being attributed to their valiant efforts to convince the world of their brilliant soothsaying. Annual Nobel Prizes for “The Team”! Hooray, they saved us from ourselves just in the nick of time!