Note: Dr. Judith Curry also has an essay on this important paper. She writes:
My mind has been blown by a new paper just published in Nature.
Just when I least expected it, after a busy day when I took a few minutes to respond to a query from a journalist about a new paper just published in Nature [link to abstract]:
This has important implications for IPCC’s upcoming AR5 report, where they will attempt to give attribution to the warming, which now looks more and more like a natural cycle. See updates below. – Anthony
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Guest essay by Bob Tisdale
The recently published climate model-based paper Recent global-warming hiatus tied to equatorial Pacific surface cooling [Paywalled] by Yu Kosaka and Shang-Ping Xie has gained a lot of attention around the blogosphere. Like Meehl et al (2012) and Meehl et al (2013), Kosaka and Xie blame the warming stoppage on the recent domination of La Niña events. The last two sentences of Kosaka and Xie (2013) read:
Our results show that the current hiatus is part of natural climate variability, tied specifically to a La-Niña-like decadal cooling. Although similar decadal hiatus events may occur in the future, the multi-decadal warming trend is very likely to continue with greenhouse gas increase.
Anyone with a little common sense who’s reading the abstract and the hype around the blogosphere and the Meehl et al papers will logically now be asking: if La Niña events can stop global warming, then how much do El Niño events contribute? 50%? The climate science community is actually hurting itself when they fail to answer the obvious questions.
And what about the Atlantic Multidecadal Oscillation (AMO)? What happens to global surface temperatures when the AMO also peaks and no longer contributes to the warming?
The climate science community skirts the common-sense questions, so no one takes them seriously.
UPDATE
Another two comments:
Kosaka and Xie (2013) appear to believe the correlation between their model and observed temperatures adds to the credibility of their findings. They write in the abstract:
Although the surface temperature prescription is limited to only 8.2% of the global surface, our model reproduces the annual-mean global temperature remarkably well with correlation coefficient r = 0.97 for 1970–2012 (which includes the current hiatus and a period of accelerated global warming).
Kosaka and Xie (2013) used the observed sea surface temperatures of the central and eastern equatorial Pacific as an input to their climate model. By doing so they captured the actual El Niño-Southern Oscillation (ENSO) signal. ENSO is the dominant mode of natural variability on the planet. In layman terms, El Niño and La Niña events are responsible for the year-to-year wiggles. It’s therefore not surprising that when they added the source of the wiggles, the models included the wiggles, which raised the correlation coefficient.
Table 1 from Kosaka and Xie (2013) is also revealing. The “HIST” experiment is for the climate model forced by manmade greenhouse gases and other forcings, and the “POGA-H” adds the tropical Pacific sea surface temperature data to the “HIST” forcings. For the modeled period of 1971-1997, adding the ENSO signal increased the linear trend by 34%. Maybe that’s why modeling groups exclude the multidecadal variability of ENSO by skewing ENSO to zero. That way El Niños and La Niñas don’t contribute to or detract from the warming. Unfortunately, by doing so, the models have limited use as tools to project future climate.
UPDATE2 (Anthony): From Dr. Judith Curry’s essay – she writes at her blog:
The results in terms of global-average surface temperature are shown in Fig 1 below:
In Fig 1 a, you can see how well the POGA H global average surface temperature matches the observations particularly since about 1965 (note central Pacific Ocean temperatures have increasing and significant uncertainty prior to 1980).
What is mind blowing is Figure 1b, which gives the POGA C simulations (natural internal variability only). The main ’fingerprint’ of AGW has been the detection of a separation between climate model runs with natural plus anthropogenic forcing, versus natural variability only. The detection of AGW has emerged sometime in the late 1970′s , early 1980′s.
Compare the temperature increase between 1975-1998 (main warming period in the latter part of the 20th century) for both POGA H and POGA C:
- POGA H: 0.68C (natural plus anthropogenic)
- POGA C: 0.4C (natural internal variability only)
I’m not sure how good my eyeball estimates are, and you can pick other start/end dates. But no matter what, I am coming up with natural internal variability associated accounting for significantly MORE than half of the observed warming.
The paper abstract:
Recent global-warming hiatus tied to equatorial Pacific surface cooling
Yu Kosaka & Shang-Ping Xie Nature (2013) doi:10.1038/nature12534
Despite the continued increase in atmospheric greenhouse gas concentrations, the annual-mean global temperature has not risen in the twenty-first century1, 2, challenging the prevailing view that anthropogenic forcing causes climate warming. Various mechanisms have been proposed for this hiatus in global warming3, 4, 5, 6, but their relative importance has not been quantified, hampering observational estimates of climate sensitivity. Here we show that accounting for recent cooling in the eastern equatorial Pacific reconciles climate simulations and observations. We present a novel method of uncovering mechanisms for global temperature change by prescribing, in addition to radiative forcing, the observed history of sea surface temperature over the central to eastern tropical Pacific in a climate model. Although the surface temperature prescription is limited to only 8.2% of the global surface, our model reproduces the annual-mean global temperature remarkably well with correlation coefficient r = 0.97 for 1970–2012 (which includes the current hiatus and a period of accelerated global warming). Moreover, our simulation captures major seasonal and regional characteristics of the hiatus, including the intensified Walker circulation, the winter cooling in northwestern North America and the prolonged drought in the southern USA. Our results show that the current hiatus is part of natural climate variability, tied specifically to a La-Niña-like decadal cooling. Although similar decadal hiatus events may occur in the future, the multi-decadal warming trend is very likely to continue with greenhouse gas increase.
Stephen Wilde (August 29, 2013 at 1:13 am) wrote:
“[…] changing the emphasis on solar effects from the length of the solar cycle to changes in the mix of particles and wavelengths affecting stratosphere temperatures […]”
Observation corrects a widespread, persistent solar-terrestrial-climate misconception:
The Sun CHANGES Earth’s Ozone: Terrestrial total column Ozone CHANGE (NOT ozone) is coherent with the solar activity cycle. In other words: The solar activity cycle is 1/4 of a cycle ahead of the terrestrial total column ozone cycle.
Externally governed equilibration opportunity limits Earth’s degree of progression towards equilibrium via circulatory pattern persistence. At interdecadal timescales, the Sun changes the amount of time Earth has to equilibrate. Equilibration opportunity is governed by changes in the length of time-streaks during which solar activity persists above and below critical thresholds.
The “internal” decadal & multidecadal variation narrative is based on patently false inferential assumptions that thoroughly & completely fail diagnostics. Specifically it catastrophically fails implicit assumptions of uniformity & symmetry. There’s only one sensible option: It must be abandoned.
@ur momisugly Richardscourtney Thanks for the reply – the implication is rather troubling though:
a natural cooling phenomena that happens to near-perfectly match the claimed CO2 warming? Goldilocks comes to mind.
Ulric (8:45 am), Earth responds as a unit. The spatial differential is multi-axial. The (long-run central limit) attractor is a simple case that clarifies what we know from common sense: The primary axis is equator-pole. I’m not willing to discuss this further with you here & now. No offense intended.
The chart Peter Vaughan shows the solar /ozone thus climate relationship quite well.
SOLAR/CLIMATE RELATIONSHIPS: The CATCH is the degree of magnitude change of solar activity and duration of time of solar activity has to reach certain critical LEVELS, in order to overcome random earthly climatic changes and or influence these random earthly climatic items.
This is why correlations with solar activity are hard to come by when the sun is in a regular rhythmic 11 year sunspot cycle with peaks and lulls.
However this current prolonged solar minimum should prove their are indeed correlations between solar changes and climate if the solar changes are strong enough and sustained enough over time.
Excellent blog post on this by Lubos:
http://motls.blogspot.com/2013/08/pacific-waters-as-excuse-for-warming.html#more
People that can’t see a climate /solar connection are very short sided.
@Salvatore Del Prete – sighted – “short sighted”.
Johnnie says:
August 30, 2013 at 7:03 am
The facts behind modelers’ assumptions have never been in evidence. They just assumed the feedback effects they needed to get the results they wanted. GIGO, pure & simple. The models are worse than worthless.
Ironically, discovery by a fisheries researcher, not a climatologist, of the PDO was published in 1997, at the end of the 20-year warming phase.
Author quoted on Scripps IoO report on paper:
http://keelingcurve.ucsd.edu/solving-the-mysteries-of-hiatus-in-global-warming/
“That speaks to the challenge in predicting climate for the next few years,” said Xie. “We don’t know precisely when we’re going to come out of [the hiatus] but we know that over the timescale of several decades, climate will continue to warm as we pump more greenhouse gases into the atmosphere.”
My comment:
No one can possibly “know” any such thing. The naturally-changing climate might well cool over the next several decades, or both cool & warm.
The GIGO models are worse than worthless, based upon feedback assumptions for which no evidence exists, indeed which have been shown false.
Exactly Mioldonharlani the models are worthless.
Sleepalot:
Your post at August 30, 2013 at 10:31 am says in total
That is the second time in this thread where you have asserted I said other than I did.
Read what I wrote and comment on that.
“CO2 warming” may not have sufficient magnitude for it to be discernible. In that case the “cooling” is an interruption to natural warming. Your “Goldilocks” assertion is merely an assumption concerning the magnitude of “CO2 warming”.
You are making assumptions and each time I point out you have made one then you replace it with another while claiming I said other than I did.
Richard
Paul Vaughan says:
August 30, 2013 at 10:31 am
“Ulric (8:45 am), Earth responds as a unit.”
The point being that the solar wind has the greatest effect in the polar regions.
@ur momisugly Salvatore Del Prete
There’s actually another layer (2nd order) to the solar-ozone phase-relations I mention in my reply to Joe Bastardi, but people need a chance to catch up by first learning the methods outlined by Donner & Thiel (2007).
Once people get that far, I’ll be able to efficiently outline how to:
a) easily overcome the systematic biases in Donner & Thiel’s phase estimates.
b) take the sun’s multidecadal pulse using a wavelet tachometer.
Donner & Thiel’s scale-resolved methods are beautiful even without improvement, but it’s a breeze to refine them for precision and extend them to the more generalized case.
If ever / whenever I have sufficient time & resources via the support of the local university, I’ll be willing and able to write all of this up formally. Before then it’s not even remotely feasible given the hard constraints under which I currently operate, so informal communication is all I’m volunteering at this time. Frankly, I don’t value formality (it’s unnecessary), but I do respond to paychecks…
Regards
Correlation again. What is with the correlation? If you can’t match the energy required to overcome natural variation (which is very, very powerful) with the energy available from solar changes (which is very very tiny), you have nothing more than tea leaves. Why would you be pushing tea leaves on a gullible public? Isn’t that what AGWers have done?
Of all the entities that have the capacity in stored energy to release it into the sources of Earth’s weather patterns (the semi-permanent pressure system cells and jet streams) to the extent that these systems are forced to change to another pattern, the oceans are the only ones that rise to plausible consideration. And that is it in a nutshell. The solar game is just playing with data to find wriggles that match without ever considering this very important issue: the driver of the change has to be plausibly capable of doing it.
Pamela, the solar-terrestrial-climate weave is observed. It’s not a correlation. It’s not a theory. It’s an observation. You can no more sensibly deny it than you can deny 1+1=2. Observation takes precedence over your abstract theories, which are based on false &/or distorted assumptions that flatly fail empirical diagnostics. My patience with your ignorance &/or deception has expired. The false premises & harassment you’re attempting to direct my way are not welcome.
– – –
I dare all who fancy themselves serious contributors to:
a) attempt to reproduce Donner & Thiel’s (2007) Figure 4. (I suspect that not a single WUWT regular can do it, even though it’s easy to do from scratch in just a few spreadsheet columns.)
b) attempt to substantively disparage Donner & Thiel’s (2007) methods. (Good luck with that as the methods are rock solid & beautiful.)
Pamela Gray says:
“Correlation again. What is with the correlation? If you can’t match the energy required to overcome natural variation (which is very, very powerful) with the energy available from solar changes (which is very very tiny), you have nothing more than tea leaves. Why would you be pushing tea leaves on a gullible public? Isn’t that what AGWers have done?”
In fact you are repeating what the AGWers have done, by assuming natural variation is internal, and by overlooking the very large changes in solar plasma speed. Looking for correlations is the right approach, spot the El Nino’s: http://snag.gy/UtqpX.jpg
“Of all the entities that have the capacity in stored energy to release it into the sources of Earth’s weather patterns (the semi-permanent pressure system cells and jet streams) to the extent that these systems are forced to change to another pattern, the oceans are the only ones that rise to plausible consideration.”
Changes in the jet streams and the trade winds lead and drive the oceanic modes.
Paul Vaughan says: August 30, 2013 at 10:40 pm
Hello Paul.
Thank you for your comments, which are most interesting.
Regards, Allan
Richardscourtney wrote: “That is the second time in this thread where you have asserted I said other than I did.”
This is my third post in this thread. My first post contained my own original thoughts.
My second post contained my impressions drawn from your kind reply: you quoted it in its enitirety. At no time have I asserted that you have said anything _at all_ !
(I think you must have me confused with someone else. Still, no harm done. Least said, soonest mended.)
Richardscourtney wrote: “Read what I wrote and comment on that.”
Done.
Sleepalot:
I write to offer you an apology.
Yes, as you suggest in your post at August 31, 2013 at 3:53 am, I did confuse you with someone else (i.e. ironargonaut) and I responded to your reasonable comment as though it was another in the series from him/her/them.
That was wrong of me and I have no excuse: I made a mistake and so I made an unfounded and untrue accusation against you.
Thankyou for pointing out my error.
I withdraw my misdirected – so untrue – accusation, and I provide this complete and public apology.
Richard
No problem, I’m English – I’m not afraid to be called an idiot, I’m afraid of embarrassment – please don’t appologise. Didn’t you see that “least said, soonest mended?” Please don’t reply.
Ulric Lyons says:
August 31, 2013 at 1:06 am
Pamela Gray says:
“Correlation again. What is with the correlation? If you can’t match the energy required to overcome natural variation (which is very, very powerful) with the energy available from solar changes (which is very very tiny), you have nothing more than tea leaves. Why would you be pushing tea leaves on a gullible public? Isn’t that what AGWers have done?”
In fact you are repeating what the AGWers have done, by assuming natural variation is internal, and by overlooking the very large changes in solar plasma speed. Looking for correlations is the right approach, spot the El Nino’s: http://snag.gy/UtqpX.jpg
There is an approach that reconciles solar forcing (little energy) with natural oceanic driven cycles (large energy). It is to regard the ENSO cycles, and the epiphenomena thereof, the PDO, AMO and other such multidecadal cycles, as weakly forced nonlinear oscillators interacting with eachother. There is a long and well established science and literature on such systems.
So there does not need to be a hostile standoff between a solar forcing camp and an internal cycle camp.
Scientists looking at ENSO have long suspected that it is a kind of nonlinear oscillator, although an intermittent, not continuous one. A post here a couple of years ago showed an analogy between ENSO and the classical widely studied model of nonlinear oscillation, the Belousov-Zhabotinsky reaction. The conditions needed for a nonlinear oscillator include positive feedback in a dissipative far-from-equilibrium system; these conditions are met in the ENSO where the positive feedback takes the form of the well-established Bjerknes feedback (fig 5.3) in which Peruvian upwelling and trade winds alternately reinforce or cancel mutually.
Nonlinear oscillators come in three types: strongly forced, weakly forced and unforced, the latter driven by internal cycling only. Pushing a child on a swing is a strongly forced oscillator – forcing and forced frequencies are the same although the system develops chaotic instabilites. In a weakly forced nonlinear oscillator, the emergent frequency of the oscillator has a complex relationship with the forcing frequency (or frequencies), such as in the complex tidal oscillations in a coastal bay with one or more narrow inlets to the sea. The heartbeat is an unforced nonlinear oscillator. The propagation of action potentials between helically patterned myotomes represents such a strong positive feedback that a highly regular pulsation (contraction starting at the left ventricle) with monotonic frequency results. Note that this is the case in the healthy heart – in heart disease factors interfering with intermyotome propagation result in cardiac irregularity, and a pacemaker is needed to set an even beat: here an unforced nonlinear oscillator needs to be replaced by a strongly forced nonlinear oscillator.
It is possible that ocean cycles are type 3, internally driven only. However it is also possible that ocean-driven climatic cycles such as ENSO and the PDO could be the second type, a weakly forced nonlinear oscillator, and that the weak periodic forcing could come from solar-associated cycles of various time periods.
It is also well understood that longer, century and millennial scale cycles in oceanic circulation can affect climate on these time-scales, involving phenomena such as the bipolar seesaw and interhemispheric heat piracy. Many papers on this can easily be found, such as:
http://www.geo.arizona.edu/sites/www.geo.arizona.edu/files/web/Cohen/pdf/80%20Brown%20et%20al%202007%20GRL.pdf
http://geology.gsapubs.org/content/38/4/383.full.pdf+html
http://www.clim-past-discuss.net/7/397/2011/cpd-7-397-2011.pdf
http://www.nature.com/nature/journal/v457/n7233/full/nature07770.html
I agree with Pamela Gray that the most powerful and direct driver of climate is the oceanic natural cycles, and that the atmosphere only approach taken both by the CAGW and the solar forcing camps make the profound mistake of treating the oceans as a passive puddle, responding in real time to surface input. However Paul Vaughan has clearly identified a compelling linkage between solar and atmospheric phenomena such as ozone. Also, associations between historic cool periods and sunspot minima (Maunder, Dalton) are recognised widely even by AGW scientists.
Thus I feel it makes most sense to look at a paradigm of ocean-driven systems of various time scale as weakly forced nonlinear oscillators, forced by several external periodically altering inputs such as solar oscillations and solar-atmospheric spatio-temporal patterns.
phlogiston said:
“However it is also possible that ocean-driven climatic cycles such as ENSO and the PDO could be the second type, a weakly forced nonlinear oscillator, and that the weak periodic forcing could come from solar-associated cycles of various time periods.”
The solar wind is often slow a year or two after solar cycle minimum’s and around maximum’s, but such events are of course not confined only to these points:
http://snag.gy/UtqpX.jpg
Phlogiston, you make the mistake of jumping to your second possibility without ruling out the null hypothesis. The entirely intrinsic global oceanic/atmospheric random -not chaotic- circulating set of systems is strongly teleconnected and strongly maintained in the larger sense by the axial tilt and path around the Sun, the Earth’s Coriolis effect, and its land barriers. Solar shortwave IR provides a fairly steady stream of energy at the outer surface of the atmosphere. But by the time the SWIR makes it to the planet’s surface the amount can be substantially changed by oceanic/atmospheric conditions entirely intrinsic to the Earth. This internal set of systems builds regime shifts, brings them up and down, releases regime shifts, sets up a dive into a different one, brings that one up and down, provides for stable periods, is random so hard to predict on a longer term basis, and hardly ever cancels out to zero within any kind of adequately measured string of data, even with proxy data to extend the string. That ladies and gentlemen is the null hypothesis and is a very plausible -because it is very powerful- reason for weather pattern variations, of which some are good, some are bad, and some are just so-so.
Why look for external drivers while the internal one is so powerful? You would only do this if you are emotionally invested in a pet theory. Pursuing a pet theory while ignoring the null hypothesis, which has not been adequately researched even to this day, exposes you as a poor excuse for a scientist, regardless of your credentials.
Pamela Gray says:
August 31, 2013 at 9:10 am
I did not in fact rule out the null hypothesis of unforced nonlinear oscillation. I was just pointing out that nonlinear oscillators can be either unforced (generate oscillations internally) or forced – weakly or strongly.
There is one timescale where external astrophysical forcing of climate is undeniable. Look at the temperature history of the last 3 million years, our current glacial period. From 3-2 million years ago, interglacials pop up regularly every 41,000 years, in time with the Milankovich precession wobble cycle. Then about a million years ago we have the mid-Pleistocene revolution and interglacial timing changes to match the longer 100,000 year eccentricity cycle. The temperature trace is not however a neat series of upticks but a quasi chaotic saw-edge in which some interglacials are double-headed (the ones occurring at nodes of maximal eccentricity oscillation). Here there can be no serious doubt that the system is an externally forced quasi-chaotic nonlinear oscillator in which “glacial” and “interglacial” are alternate stable attractors.
The fractality of nature implies that natural patterns that we see on long or large scales can sometimes be repeated on smaller scales. So it can be conjectured that climate oscillations that are observed over millenial, century and decadal scales might also be weakly forced by astrophysical stimuli. This is a reasonable extrapolation from what we already know about Milankovich glacial-interglacial forcing.
But equally, they might not be.