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.
Excellent comment from Henry Clarke above.
Bob, we need appropriate analogies to communicate this idea about the claim being all warming is caused by AG GHG’s and cooling is caused by ENSO.
We hear the sound of applause behind the curtain. We send an investigator to see what is creating it. They peek round the curtain and report that it is the sound of one hand clapping. There is no other hand.
I suggest that this paper’s claim is that global temperature changes are caused by the climate equivalent of the sound of one hand clapping.
So ENSO is 60%. The AMO will be 30% at least. The AO will be another 20%. Something Antarctic will be an extra 25% and a number of other contributions will bring the total to 200%. At some point, at some level, they will have to admit there are two hands clapping. When that happens AGW is history – the sort of history that is omitted from books in embarrassment. What a sad chapter in the history of human endeavor.
This is absolutely in line with what we have postulated here on WUWT for years. No one is surprised by this, except those not paying any attention. Kudos to Bob for teaching us all more about the oceans/ENSO through the years.
I think that we are observing the warmists between volte and face.
Wow. I had thought we were many, many years away from an actual, meaningful science on the climate appearing in any of the usual journals, but this is a big step along that road. Obviously it raises more questions that answers (which the authors have clearly shied away from asking) but this is important stuff, for two reasons:
1. There has been no warming this century. Stated quite clearly in a paper published in Nature. No more quibbling from alarmists can be accepted now. They are the data deniers, not us.
2. At least 50% of the warming is not man made (possibly, with due respect to the usual caveats about models, but the alarmists have always loved models so they can’t reject this one out of hand now), again published in Nature.
I see a lot of alarmists being referred to this paper from now on, especially by me.
So my 60 year cycles for predicting droughts, floods, wild fires, tornadoes hurricanes, etc. is still okay? Bob Tisdale and others have explained the ENSO, PDO, AMO distribution of heat for years and these guys are blowing everyone away with this? Did your book get referenced, Bob (not a chance!)?
We can but hope the temperature record reflects predominately natural forces. The higher the sensitivity to AnthroGHGs, the colder it would now be without their effect.
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“Gary Pearse says:
August 28, 2013 at 6:52 pm
Add to this the Eschenbach Effect, which caps the tropical SSTs at a max of 31C, and we have another constraint on CO2 warming. The radiative effect of increasing CO2 pushes against the development of clouds and thunderstorms in the ITCZ which “chimney” the heat up into the upper atmosphere where it escapes to space.”
Looks like God is better at Climate Science than the IPCC!
We will not throw away all our efforts to make the case for AGW and that;s why we have written this paper to explain why we still need a carbon tax to prevent thermogeddon in the future.
Janice Moore says:
August 28, 2013 at 9:04 pm
“Ulric Lyons (not joking at 8:40pm),
Would you please provide some Leif Svalgaard-proof data proving your assertion that there is a “Sun signal”? What data shows it was “strong” and over what time period(s)? What data shows it was “weak” and over what time period(s)?”
Plasma speed, El Nino conditions and negative AO/NAO occur at lower speeds, La Nina conditions and positive AO/NAO at higher speeds. The solar wind speed has a direct effect on polar lower atmospheric pressure. This has been studied at least in the Antarctic following CME impacts.
http://snag.gy/UtqpX.jpg
I would even suggest that part of the upper atmospheric heating is due to solar plasma speed, and this may also have an effect on Earth’s energy budget, either directly and/or though circulation changes forced down through the atmospheric levels.
I also do solar based forecasts at the scale of weather, which show the short term changes in Arctic pressure that are causing the latitudinal shifts in jet stream must be directly solar forced. The sheer volume alone of hindcasts that I can provide at weekly to monthly scales, e.g. 350yrs worth through CET by itself adequate to show that the solar linkage must be there at these scales. I know that the correlations are easily robust enough to be taken seriously by Leif if he were to take a look, including my latest findings on solar cycle phase catastrophe every 10 solar cycles, which does agree with his periodic analysis.
Any one can immediately see by adding a short visual gap in the latest HADCRUT global average data set how our postwar C02 burst witnessed a variation in temperature that was no different than the one before it:
http://www.woodfortrees.org/plot/hadcrut4gl/from:1955/to:2012/plot/hadcrut4gl/from:1895/to:1950
“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.”
Technically true, but totally worthless. This kind of statement should not be allowed in a serious journal, but I guess that’s why it’s in Nature.
How about some numbers, what is the trend in warming they expect to continue?
I and many other have been saying this for years. That this quasi-cyclical warming means that feedbacks to warming can’t be nearly as high as believed. Probably half.
That is what can easily be inferred from this paper, but not only do they seem to avoid it, they use language that suggests the large warminging will happen. But warming much higher that the very benificial warming we’ve experience already is all but impossible.
That is the hope. But even now I see them trying to weasel out of it.
Natural variability accounting for half to somewhat more than half actually makes perfect sense. CO_2 probably does not have zero warming effect (and what effect it has is still swamped by the error bars the authors give honestly enough on the right) but it was always clear that it was (probably) not responsible for most of it. 0.2 C plus or minus 0.2 C over forty years would seem about right, suggesting moderate negative feedback, which is just the ticket to create a reasonably stable climate system. Of course this small a rise is literally lost in the noise of natural variability and could be anywhere from 0 to slightly OVER half the warming and still easily be within error bars, especially when all sources of natural variability are not taken into account.
Now, of course, warmistas will assert that this is just one model, while there are thirty or forty GCMs that show extreme CO_2 linked warming and that also agree decently with at least part of this data (but which, perhaps, do not account for ENSO correctly). Surely with (say) forty to one showing warming, warming wins, right?
Not at all. As I’ve been hammering home on this blog ever since I read AR4’s summary for policy makers in some detail, the average of 40 models that individually fail and hence can be rejected in favor of the null hypothesis when compared to actual data is a statistically meaningless average of 40 failed models. One successful model is worth more than 40 thousand failed models, no matter how small the “standard deviation” of the failed model average gets.
We can now get out the popcorn and watch the proponents of the failed models try to convince the general scientific community (and themselves!) that even though the entire ensemble of results produced by their model(s) one at a time lies 95% or more outside of reality, those models are correct where a model that also contains the same physics but happens to agree with the data is incorrect. An excellent test for the honesty of the community compared to its political and economic polarization.
Note well, even the model above almost certainly fails to capture the climate. We are well into von Neumann’s trunk wiggling regime, and there are factors such as the hypothesized magnetic solar connection that are omitted from the GCMs (and, I imagine, from the models above) that could have a further effect. For example, it is by no means impossible that these effects are responsible for some fraction of the residual rise, say another 0.1 to 0.2 C. That doesn’t make the fractional split of 0.2 CO_2 to 0.4 C natural wrong per se, because all of these components are smaller than the error bars and model dependent, and there are many ways to fit the data, but it is just another way that the “natural component” could either be underestimated or be multivariate — perhaps ENSO is in some roundabout way driven by the solar magnetic state and associated cloud cover.
The truly amazing thing is that the paper is published in Nature. What a turnaround! It will be very, very difficult to ignore, and given that the climate community is in a state of shock as it is trying to pretend that the current neutral trend doesn’t really exist, given that (in my opinion) most scientists really do try to be honest, although as humans they can be honestly mistaken, honestly allow bias into their considerations, honestly give too much weight to the voice of the herd, it is quite possible that we will see rapidly widening cracks in the facade of unanimity.
rgb
The climate liars needed a way to explain the warming “pause”. For them, CAGW has simply been postponed, giving us a bit of time to work on what they will claim is still a serious problem. My guess is that they will use a kitchen sink approach, throwing in volcanoes, manmade aerosols, and even the “hiding heat” in addition to ENSO. In the meantime, they still have the extreme weather, melting arctic, hotspots, and other climate nonsense with which to try to keep the CAGW anti-science alive.
The science is slowly becoming more objective.
This result has always been obvious to anyone who looked at the issue objectively.
But whenever a climate scientist took this step, they found global warming was only 25% to 50% of what they projected so they just had to drop it and move on to some other disaster scenario/projection.
This movement actually prevents the scientists involved from facing the facts.
If we take this paper at face value, we can only conclude that we’d currently be in another Little Ice Age but for global warming.
So thank God for global warming. 😉
Look, I am not a climate modeler, and I don’t even play one on TV, but I am an environmental chemist….
It seems to me that someone here would have sufficient expertise to design a climate model that would incorporate the following factors:
1. ENSO variations from 1950 to present.
2. Solar cycle amplitude variations from 1950 to present.
3. Aerosol and other fine-particulate variations from 1950 to present (whether natural [volcanic], or anthropogenic).
4. AMO variations from 1950 to present.
This model would NOT EVEN INCLUDE (to begin with), CO2 variations from 1950 to present AT ALL.
In my humble opinion, a model simply incorporating the 4 main factors I listed above would probably give a correlation coefficient of > 0.95 to the actual temperature variations that we have seen from 1950 to present, thus showing that anthropogenic CO2 emissions are statistically insignificant. I am sure that someone more knowledgeable than I could easily come up with a few more minor (non-CO2) factors to refine the model even further, but I suspect the 4 factors I mentioned might even be sufficient.
If such a model could be designed, and it could be accepted for publication in a reputable journal, it would be an instantaneous death-blow to the whole CAGW meme. Frankly I am shocked that some reputable scientists have not attempted to do this, but then again, coming up with the necessary funding would probably be extremely difficult if not impossible. Also, getting such a paper through the “peer review” (lol) process at any “reputable” (lol again) journal might also be extremely difficult if not impossible due to the current sad state of “science” when it comes to anything climate-related.
I am suddenly reminded of Aaksofu:
http://wattsupwiththat.files.wordpress.com/2009/03/akasofu_ipcc.jpg
The equatorial Pacific ocean is the same temperature today that it was 1850.
It has an oscillation of +/- 2.5C but the neutral temp level of 27.5C (Nino 3.4 region) has not changed in 163 years.
Why is that? It only happens to be the most important region on the planet in terms of influencing the climate so it is an important question.
I still like Stephen Wilde’s “NCM” the best. It just seems logical and realistic.
I would like to see someone scientifically debunk it.
There is a great deal of excellent discussion/hypothesis’ brought forth here in the comments.
There are many possible/likely factors that contribute to changes in climate and likely all brought up here have varying magnitudes of influence at different times. It’s a completely chaotic environment. It will most likely never be “modeled” with any degree of accuracy as claimed by the so-called “climate scientists”. But it is fascinating to follow the various hypothesis that are presented. Let me toss in Willis’ thermostat hypothesis to the mix for good measure.
CO2 doesn’t seem to play much of a role here, even the trolls tread lightly with that regard. It may eventually be concluded that its radiative properties toward the earth surface are offset by the same amount to space and therefore a wash.
I don’t know the answers and I don’t think anyone does but the discussion certainly takes up a lot of my time. Inquiring minds need to know!
“…natural internal variability associated accounting for significantly MORE than half of the observed warming.” Well, who would of thunk it? The AGW Skeptics, that’s who. Haven’t we been saying this for over 20 years now? I know I have! The evidence for it has been there all along.
Let us warmly welcome all mainstream climate scientists back to reality.
Question for everybody out there that thinks greenhouse gases have little or no effect.
When will the cooling start?
Right now I agree we are paused and this paper points to why; however, shouldn’t we really be cooling if there no AGW?
James, what has been the average decadal warming, globally, for the past 90 years? I’ve dropped the cyclical low period of the 1880s and chosen a cyclical high period. Just cherry picking like alarmists.
http://bobtisdale.files.wordpress.com/2013/07/figure-37.png
PeterB and Correction to comment on 28/9.34pm
The first part of the quote from the conclusions from my blogpost at
http://climatesense-norpag.blogspot.com
should read
“To summarise- Using the 60 and 1000 year quasi repetitive patterns in conjunction with the solar data leads straightforwardly to the following reasonable predictions for Global SSTs”
Peter at this time we need to abandon the modelling approach for a pattern recognition method linked to in the earlier comment.Further modelling just leads to epicycle type adjustments to preserve the basic assumptions of the model- in this case the idea that CO2 is the main climate driver.