ECS Pause

JCH says:

It just seems basic to me that if the warming hiatus that never happened was caused by a strengthening of ocean heat uptake efficiency during a period of time that coincided with Matt England’s anomalous intensified tradewinds, which both actually happened and then went away, that the observations are a bit F’d Up for primetime. So which longterm variation are they talking about? Because, as far as I can find, Matt England’s anomalous intensified tradewinds are a one-off phenomena. There is no variation to them: so far. The winds came; there was a warming hiatus in improvable datasets; the winds subsided; GMST has been shooting through the roof ever since. Anyway, I’m reading all the cloud stuff. Seems to be pointing mostly in the same direction: upward ECS.

zebra says: April 29, 2018 at 1:08 pm
” let’s assume that there was such a spike in GMST the past 3,000 years. So what? That was then, this is now. How does it affect the consensus about CO2 causing the current increase in system energy, which shows up as increasing GMST and the other well-known phenomena?”

CO2 should cause warming with an increase in concentration in the atmosphere.
A general, but not complete consensus.
However observations are falling badly behind computer model predictions of what the temperature rise should be.
The physics may not be totally right somewhere. Unlikely.
One or more of the many climate model assumptions appears wrong. Bing!
Or as AD in the next thread says, natural variability may be playing up with the temperature rise and could do so for the next 155 years or more.
Hence the problem with the consensus. If natural variability can effect ECS and hence temp for a long period then many of the skeptics [me included] can logically introduce an element of doubt into the consensus. Some of course say CO2 has no effect and that the warming spike to date could be explained purely from natural variability, not CO2.
Others that ECS may be lower than expected so that the warming will not be as severe as predicted.
Such points are valid while observations keep deviating from models.
If they persist they would demand an investigation into why.
If warming does return to the pattern expected of it then this all would be moot.
Your answer in brief is that a consensus tends to ignore and belittle data, people and ideas that do not conform with the consensus, even when they have elements of truth that should be welcomed into a fuller understanding.


John Hartz says: May 4, 2018 at 6:44 pm
“Back to basics: Climate Sensitvity (CS) is an index created to compare model runs. It is model output, not a model input.”
Dave_Geologist says: April 27, 2018 at 2:43 pm
” Dessler’s point AFAICS is that if you take a suite of physics-based models, where you know the ECS in advance, and try to calculate it the way LC13 and LC18 do, you get the wrong answer.”

The old chestnut, Lucia [whom I trust] used it as well, is that ECS is an emergent property of climate models. The truth is that the ECS is hardwired into all the GCM.
At around 3C.
Put 3C ECS in and 3C ECS comes out.
Compare it to the real world, the only one, where 3C rarely comes out unless you pick exact time frames of extra warming like a decade ending in a large El Nino.

Consequence is shadow boxing, dodging the real questions and answers.
Dessler is right but so is Lewis but on two different stages.
It is so easy to answer a question on the first stage show in the second show arena.dikranmarsupial says: April 24, 2018
Even angech’s own sources refute him. His original claim was:
These can give an indirect record of past temperatures, but only locally. Such records indicate that Temperature changes equivalent to the modern 150 year warming have happened a number of times in the past 3000 years. [emphasis mine]
and he supports that with:
“The NRC committee stated that “The basic conclusion of Mann et al. (1998, 1999) was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years. This conclusion has subsequently been supported by an array of evidence that
includes both additional large-scale surface temperature reconstructions and pronounced changes in a variety of local proxy indicators”
and says: This basically agrees and supports what I have said. There are possible higher and lower spikes in the temperatures in the past that do not show because of “the wide error bars” as one goes backwards and the “uncertainties inherent in temperature reconstructions for individual years and decades are larger than those for longer time periods’.

DM “Err, no it doesn’t, it says that the recent warming is unprecedented.”

Having been called out in the past for not fully quoting comments I guess I can do a tu quoque?
The NRC did not say “the recent warming is unprecedented.” Mann et al said that.
The part that DM leaves out says clearly plausible only with substantial uncertainties before 1600.
I will append the bit he missed by accident.

“Based on the analyses presented in the original papers by Mann et al. and this newer supporting evidence, the committee finds it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium”, though there were substantial uncertainties before about 1600?”.

“Note also the goal-post shift from “have happened” to such spikes being “possible”, without acknowledging the weakening of his position. Rather shabby.”

Sorry DM I have not changed my position. No goal post shift. Read my comment again noting “have happened” refers to events ” past temperatures, but only locally” which are well known and real.
The ”spikes” being possible refers to the separate concept that such temperature spikes may have been general rather than local and would not be visible due to the large error range in time and temperature.
Good try.


  • BBD says:

    I would like your opinions on the statistical probability of such events existing [my statement] rather than sidetrack to the question of how as you have an excellent understanding of the statistics involved.

    If no plausible physical mechanism exists that could produce a global warming of ~1C and ~150y in duration, there is nothing further to discuss.

    Since you cannot (will not) answer this question, I’d say we are done here.

  • angech says:

    Your comment is awaiting moderation.

    izen says: @-metzomagic
    “What physical process could possibly produce a 1 deg C spike in temperatures that disappeared without a trace within a 200 year time span?”
    It is a good question.
    A short global warming of similar magnitude to the present would need a large-scale cause.
    Solar variation.
    A large methane ‘burp’
    Albedo changes from massive global ice cover loss.”
    I could add
    Albedo changes from vegetation color changes,
    Algal or jellyfish sea plumes,
    widespread black soot deposits from a massive volcanic explosion/s,
    Prolonged excessive cloud formation,
    Two very large volcanic explosions 200 years apart.
    Recurrent runs of large El Nino events.
    or a combination of these events on smaller scales.
    A combination of several events might nudge the plausibility barrier.
    Two very large volcanic explosions 200 years apart would certainly do it but is not fair.
    I doubt that warming are only possible from massive global ice cover loss. All the ice one needs for evidence has melted.
    You have shown that some of the first scenarios lack the proof that would be needed for attribution. Most of the others should also have left some traces.
    “a lack of inevitable effects.
    We know what effects the current rapid warming has had. It is inevitable that any similar energy gain in the past would have the same effect. AFAIK there is no evidence that there was a similar sea level rise in the Holocene since the end of the de-glaciation.”
    Good point.

    I suspect if there was it would show up in the timing and observable locations of solar and lunar eclipses.
    Too esoteric for me

    “Otzi the ice man would have defrosted in any previous rapid warming as glacier mass balance shrinks. ”
    Depending on whether he fell in a crevice at the start or the end of the glacier, surely? And how long and big it was.

    “While the proxies may theoretically be able to miss a short spike in the Holocene, there are other reasons to doubt it could happen and not be evident.”
    Perhaps this quote rebuffs your very good quote
    The absence of evidence is not evidence of absence.

     Look, I think the piling on is really healthy, happy to wear it and argue it to the hills, but only with the lighter weights.
    I want to avoid a Dikran vs angech comment thread, at all costs. I think Dikran’s point of view is explicit, and clear and totally different to mine.
    He is a lot more entitled to his views due to his senior status here and his scientific knowledge and expertise.
    That is not to say that I will not put up an alternative point of view and and discuss it with the rest of you if you address the same arguments.
    ATTP’s point
    “It’s almost 20 years since the publication of the first hockey stick paper (Mann, Bradley & Hughes 1998). The hockey stick refers to millenial temperature reconstructions that look a bit like a hockey stick; a period of centuries during which temperatures appear reasonably flat, or cool slightly (the shaft), followed by a period of rapid warming starting in the mid-1800s (the blade)”
    is something I concur with.
    I point out, mathematically why this must happen with any older proxy record.
    I point out that the standard deviations grow as we go back in time and are large enough to easily encompass 1C ranges of temperature for 150 years without it having to trouble the records.
    It cannot trouble the records because the SD is much larger than 1C.
    So why the fuss?
    Why do we have to say the past 3000 years ran along with nary a squeak off the railroad straight hockey shaft?
    Internal variation too large lets denialists claim a slight risk to the scientific consensus?
    Even though when we admit it is large enough short term we can show observational ECS is too low?
    Not my problem, nor yours either if you man up to the scientific facts and work with them.
angech says:

Your comment is awaiting moderation.

The atmosphere seems to have changed a little here since the publication in a journal of this reputable paper. Or was that the publication in a previously respectable journal of this paper?
Good to see nobody arguing that it need more peer review or the editor should be sacked for letting it through with pal review.
And even better that 1.6 C now seems to have become an acceptable lower limit [not an accepted true value] instead of the cries of it must be above 2.0C.

I missed this comment by DG though Mosher did pick it up.
Kudo’s Mosher.
Dave_Geologist says: April 27, 2018 at 2:43 pm
” Dessler’s point AFAICS is that if you take a suite of physics-based models, where you know the ECS in advance, and try to calculate it the way LC13 and LC18 do, you get the wrong answer.”

Did you really mean to say that Dave?

angech says:

Your comment is awaiting moderation.

dikranmarsupial says: May 1, 2018 at 3:19 pm
angech, don’t change the subject, provide evidence to support your claim that “observations are falling badly behind computer model predictions of what the temperature rise should be.”

At last I can be helpful. evidence from an expert.
”More about Equilibrium Climate Sensitivity” earlier ATTP post
“Andrew Dessler @AndrewDessler 14 Dec 2017
Terrific session on climate sensitivity today at #AGU17. Lots of discussion about climate sensitivity (ECS) estimates from the 20th century. The problem is that estimates of ECS from the 20th century obs. record are lower (1.5-2°C) than models (3°C).”

and Andrew Dessler says: April 27, 2018 at 2:51 pm
“According to our model ensemble, 155 years is not enough to eliminate the impact of variability on the estimate of ECS. Also, you asked how internal variability could’ve turned out differently. Well, that’s exactly what our model ensemble tells us. And the answer is that it can turn out differently enough to confound our estimates of ECS.”

…and Then There’s Physics says: April 28, 2018 at 10:42 am
“”as Andrew Dessler indicates – if you do consider GCM results, they suggest that these observationally-based, energy-balance approaches tend to be biased low. “

“As far as the possibility that something may backfire”

angech says:

Your comment is awaiting moderation.

“As far as the possibility that something may backfire”
“I’m not actually a fan of the tone of Harvey et al. I think they could have presented it in a way that may have resulted in less backlash”
Dr Mitchell Taylor, booted off the board of the PBSG after 20 years of service, ” If you don’t believe that climate science is settled, you can’t be a member of the PBSG,”‘
has some interesting things to say.
I did write over at Bart’s that this article should backfire.
not least because of this pertinent comment by Taylor.
“I have been active in polar bears since 1978. I didn’t recognize 12 of the 14 names on the paper written criticizing Susan for publishing an article about polar bears because she does not have any direct experience in polar bear research or management.”
Thank you for raising the matter again.
I feel the paper goes strongly against a lot of the things that you stand for as a scientist and I am sorry you have to defend it,

angech says:

Your comment is awaiting moderation.

Put this up at Tallbloke’s.
Happy with my rationalization so thought I might share it here as well. Older blog post and out of the way. ATTP might appreciate it as some thoughts on Solar system evolution, or not.
“Planet surface temperature is dependent on pressure and solar distance.
The third component * is the actual physical makeup of the planet and its atmosphere in in question.
This seems to be partly ignored by N and Z which PM is quite right to question.
Both views are mostly right and actually support each other.
E.M.Smith rightly asks about using the earth as a laboratory. “We have a natural lab here, use it.”

We are stuck with a 14 billion year old universe in which a 4.2 billion year old solar system has recently evolved.
It is highly likely that solar system accretions throughout our known galaxies are of varying ages from just forming to perhaps 8 billion years old ending when the sun blows up.
Accretions have inbuilt heat without suns, they are not cold dead lumps of rock. Jupiter for instance would still have a reasonable temperature at the surface without the sun, as would the earth at depth.
As EM Smith implied we do have a laboratory. It is a gigantic centrifuge whose spun components have temperatures depending not only on solar, pressure and internal heating [*composition] but also on the other component of physical makeup, what materials are in the planet and it’s atmosphere*. This is determined by the age and origins of the solar system accretions.

So we have the old earth, pre stromatolites with? a CO2/N atmosphere changing to an O2/N atmosphere for instance. Did the old earth have the same temperatures as the new earth?
We have the molten earth cooling down theory. Was the earth surface 4.2 Billion years ago the same as it is now? This is the nub of the question for Tallbloke et al. Do they believe in one temp for one planet same gravity, same insolation for ever or do they agree that the evolution/age/composition of the planet can affect these figures?

Once, if we admit that composition plays a part we could go on to the admittedly small but relevant role of GHG, both water and CO2 and elsewhere others .Which exist in wildly varying amounts on different planets. I am quite happy with the concept of gravity, mass, friction and normally more temperature at depth. We have the confounding effects of Oceans being colder at depths, not hotter due to the difficult nature of defining a surface. Very easy for gas/solids only. This makes temperature determination on the earth even more difficult.
Due to the variability in the main GHG, water vapour and its role in albedo control* [a third component not considered there is room for temperature variation due to GHG including and amplified by CO2 which could theoretically move the expected temperature a few degrees away from N and Z reasonable average estimate.

The two theories complement each other. If you take the Solar, add in the Gravity and then look at the actual physical composition of the accretion [if it has a surface in the first place -definition please]. It’s own internal temperature [and how it gets out to the surface], the makeup of the planet surface [All white chalk for instance compared to black or red ferrous compounds], and the albedo and GHG effects of the gases in or not in the atmosphere [and no oceans of whatever substance please] will all modify the expected result.
PM right.
N and Z right.
In parts.”

angech says:
Your comment is awaiting moderation.
April 17, 2018 at 11:26 pm
“The topic of this thread is not H17. Nor is it SusanC. The topic of this thread is about why it matters to describe and to try to explain how contrarians megaphones operate.”
Some may have missed that.
The ends may justify the means but as ATTP says in discussing truth as your goal it does not help to move away from the the other values associated with truth to prove your point.
Twister is a good game played with people you like but it is a hard way of defending the undefendable.
Give Joshua some carte blanche.
Several comments in an oppositional vein.
Thanks for the graphs and explanations by the way. Your point is well made.

Tamino good argument on his part
The 1880 to 2018 graph NASA is a compilation of different and changing temperature measuring devices, many different and changing sites and one presumes multiple adjustments to the original raw data. Zeke has explained in the past that current NASA etc anomaly graphs have built in TOBS etc adjustments that cool the past.
Still, if that is what we have that is what we have.

Secondly the amount of variation given that a yearly annual change can be as large as 0.1C [Guess only] is actually not that impressive over 138 years, or is it not that significant?
The figures could really be absolute, not anomalies and in Kelvin to give an idea of the real overall change.

Thirdly they do suggest the presence of the little ice age and presumably there was a fall from previous moderate levels.

As with all these arguments you might at times have used similar presentations to argue for your points while knowing that a slightly different picture would be available on a bigger/smaller/different graphing scheme?
Again this is all part of the arguing but if the skeptics, or you, use facile reasoning at times how do we get to the actual truths, such as they are?

There is a WUWT post on Greenland temps as we speak. Is it possible for you to contrast it’s results with yours or take it down.
The reasons for a flat shaft,
“many proxy records spanning the last 2000 years are not annually resolved, and in some regions, most of the available records of any length lack annual resolution. The mean resolution of non-tree archives is 11 years, the median 1 year. For sedimentary archives the mean and median resolutions are 25 and 18 years, respectively.”
are easy to see.
Going back in time smooths and flattens the trend.
Observations ten million years ago [as an example of the overall not the immediate problem] May have a change in temperature resolution of a thousand years. Observations a thousand years ago can have a resolution of 11 years. Annual data such as tree rings in some long lived species struggles to reach 600 years but provides a crucial overlap between thermometers and more esoteric proxies. At a cost of smoothing out changes.
Hence the ability to see warming and cooling trends of up to 2 degrees over 100 years is lost as one goes back in time.
Here is the conundrum. One did not even need to use tree ring proxies to get a flat shaft. It is a natural occurrence of using dating temperature proxies.
But we have another proxy method of temperature reconstruction. History via written languages and history of agricultural practices and living styles by archeology. These can give an indirect record of past temperatures, but only locally. Such records indicate that Temperature changes equivalent to the modern 150 year warming have happened a number of times in the past 3000 years.
The two results can coexist happily along side each other.