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.
OK, so if the HIST trace is supposed to be just the CO2 forcing, without the ENSO, why does it only diverge in the last 15ish years. It should also diverge on the low side in 1998 dramatically. Since it doesn’t I can’t really give any credibility to this paper.
ENSO has not caused the recovery from the LIA since this recovery is an oscillation of century timescale, while ENSO is a decadal scale oscillation. The LIA recovery must be tied to a different oscillation related to deep ocean THC. Maybe linked to bipolar seesawing and interhemispheric heat piracy.
What if the century scale (MWP-LIA-now) oscillation and the ENSO-linked PDO/AMO oscillations both peak at about the same time, i.e. now? We could be at the crest of the big drop on the roller-coaster.
(But we might not be.)
Judy’s numbers are almost identical to a computation I made a few days ago (.28 vs .30 net warming from GHGs).
http://wattsupwiththat.com/2013/08/20/when-somebody-hits-you-with-that-new-ipcc-is-95-certain-talking-point-show-them-this/#comment-1395786
The bottom line is ENSO is the reason we have seen the most recent warming and the switch to the cool PDO has led to more La Niña events and now we are cooling. This is what Bob Tisdale has been describing for years. He has explained that La Niña is a recharge mode while El Niño is a heat release mode.
What happens over many decades is an extension of this short term phenomena. When you have predominately El Niño episodes the oceans are releasing heat on average for the entire period. This occurs during a +PDO cycle. The opposite occurs during -PDO cycles. The oceans start storing up heat for the next cycle. This means we should be seeing an increase in ocean heat content for many years. The alarmists will scream that this is part of climate change. However, what they don’t realize is that the oceans have been releasing heat during the recent +PDO cycle.
It’s too bad we don’t have any reliable data of historic OHC. I think it would allow a much better analysis of the heat flow.
We all seem to have different dates for when the PDO modes have ran. I prefer 1975-1976 as the start of the warm mode and 2005-2007 as the end. This would mean a cool PDO until at least 2035. However, there will be a few El Niño events during this stretch. The alarmists will jump on the first one as proof of man made global warming.
Phlogiston The suggestion that the current peak possibly marks a conjunction of the 60 and 1000 year cycles is the basis for the forecast referred to in my earlier comments and on various posts at http://climatesense-norpag.blogspot.com
eyesonu says:
August 29, 2013 at 6:34 am
…
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.
Indeed – in this context it may be significant that while AGW radiative models typically employ a Narnia-Diskworld flat earth disk, taking account of the earth’s sphericity leads to more outward than inward radiation from any atmospheric radiation sources.
James Cross says:
August 29, 2013 at 6:35 am
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?
The cooling has already started as is evident in the RSS data:
http://www.woodfortrees.org/plot/rss/from:1996.9/to/plot/rss/from:1996.9/trend/plot/rss/from:2005/trend/plot/rss/from:1996.9/to:2005/trend
Notice the blue line going down since 2005. We have just started going downhill. BTW, this is also verified by CERES and AIRS that have measured a reduction in OLR (another proxy for temperature).
James Cross says:August 29, 2013 at 6:35 am
Question: if greenhouse gases have little effect, why do you expect it to be cooling? That assumption merely ascribes cause to something else. We don’t have to know the alternative if it is not GWG, but we might figure it out. One can’t solve a problem if one assumes it is what it is not.
@ur momisugly Dr. Norman Page,
I agree that pattern recognition is perhaps the most obvious method for predicting “what the climate will do” since it is a quasi-cyclic non-linear coupled chaotic system. The nature of the system does make it quite difficult to model; however, simply in recognizing that there are patterns which can be recognized and these patterns seem to be repetitious over various cycle periods, it leads me to believe that the system could be modeled with a somewhat reasonable degree of accuracy, were the model to be well-designed (which I don’t believe that the current models are).
All of that being said, as I said in my previous post, I am not a climate modeler, nor really do I have any expertise in any area of modeling, so I may be “talking out of my a**” here, although I certainly don’t intend to be doing so.
If you throw in variations in Earth’s orbit and variations in Earth’s axial tilt, along with the four factors I mentioned in my previous post, I think the patterns which are “recognizable” could potentially be modeled pretty accurately, but my thinking so does not necessarily equate to the reality of being able to do it.
I guess I am curious, if you recognize the patterns, and believe that the patterns have predictive value, do you believe that the patterns could at least be potentially modeled with some accuracy?
@ur momisugly phlogiston
” interhemispheric heat piracy”
I am pretty sure that the World Court at the Hague has declared that to be against international law.
Richard M.
Reminds me of a deer scarer.
http://en.wikipedia.org/wiki/Shishi-odoshi
Heat accumulates like water in the bamboo tube. When it reaches a certain level, the tube tips and empties the water.
If AGW is correct, I would expect the cycles to be faster and some accumulated warming to persist while the cycle is recharging. We would get a overall warming if we look over many cycles but nothing like the extrapolation of the last warming cycle as it seems most of the models do. This would be like the low sensitivity model that Steve McIntyre posted about a month or so ago.
rgbatduke says:
“Natural variability accounting for half to somewhat more than half actually makes perfect sense. CO_2 probably does not have zero warming effect..”
Putting figures to that depends on how much that water vapour already saturates the CO2 LIR absorptions bands, and also not forgetting CO2 has less heat capacity that dry air, and absorbs solar near infra-red in some bands.
Dr Norman Page says:
August 29, 2013 at 7:13 am
Phlogiston The suggestion that the current peak possibly marks a conjunction of the 60 and 1000 year cycles is the basis for the forecast referred to in my earlier comments and on various posts at http://climatesense-norpag.blogspot.com
Oh. Thanks. I need to get out more (blog-wise). BTW I’m in China and I can access WUWT but not your page – WUWT?
Richard M and Bruce Hall,
I am asking for a prediction and I don’t just mean a downturn of a trend line. I want to when we will see temperatures back to something like 1910 levels if we want to use the Bob Tisdale graph linked above. If there is no AGW, then I would expect it in 5-10 years, wouldn’t you say?
I am a luke warmer, I think there is some AGW but it has been overestimated by most climate scientists.
Jim Cross et al The warming trend peaked at about 2003.Check the cooling SST trend since then in Fig1 of the latest post at http://climatesense-norpag.blogspot.com
For an estimate of the timing and amount of cooling see earlier comments at 28/9.34 and correction at 29/7.13
James Cross says:
August 29, 2013 at 7:36 am
I am asking for a prediction and I don’t just mean a downturn of a trend line. I want to when we will see temperatures back to something like 1910 levels if we want to use the Bob Tisdale graph linked above. If there is no AGW, then I would expect it in 5-10 years, wouldn’t you say?
No, I would expect about a net global cooling around .1C in the next 5-10 years. We should also see an increase in Arctic sea ice as the AMO falls back toward the zero anomaly line. The big question mark is the sun. We will also cross a solar minimum during that period which could add a little more cooling. We also had a weak sun around the 1910 cool period. Also keep in mind that we don’t really know the reasons for the recovery from the LIA. If those mechanisms are still in place we will not reach the 1910 temperatures. There’s been over a century of warming to overcome.
Finally, there may be a very small warming due to increased GHG emissions. I think this latest work caps it at 1C/doubling of CO2. However, it is probably smaller. Overall there are still too many unknowns to make any firm predictions.
Bob Tisdale wrote:
The climate science community is actually hurting itself when they fail to answer the obvious questions.
Of course, they have, in work such as
Global temperature evolution 1979–2010
Grant Foster and Stefan Rahmstorf 2011 Environ. Res. Lett. 6 044022
http://iopscience.iop.org/1748-9326/6/4/044022
The current “La Nada”/ La Nina has driven Texas into a multi-year drought period. I hope it passes soon.
Although this Nada/Nina phase seems to be pretty darn good at suppressing hurricane activity……
PeterB The key is your statement about the models being well designed.They could be designed much better than the current IPCC Met Office set- but I don’t think the current crop of modellers are psychologically and professionally able to acknowledge their gross errors of judgement and start over .Therefore for the next 5 years or so other approaches are the better way ahead.
PeterB in Indianapolis says:
August 29, 2013 at 7:20 am
@ur momisugly phlogiston
” interhemispheric heat piracy”
I am pretty sure that the World Court at the Hague has declared that to be against international law.
South-North ocean heat piracy is currently conducted by Atlantic Equatorial Counter-current which becomes the Carribean current. Will the Hague join the pursuit of Jack Sparrow?
Seidov, D. and Maslin, M. (2001), Atlantic ocean heat piracy and the bipolar climate see-saw during Heinrich and Dansgaard–Oeschger events. J. Quaternary Sci., 16: 321–328. doi: 10.1002/jqs.595
Abstract
The millennial-scale asynchrony of Antarctic and Greenland climate records during the last glacial period implies that the global climate system acts as a bipolar see-saw driven by either high-latitudinal and/or near-equatorial sea-surface perturbations. Based on the results of recent modelling of generic Heinrich and Dansgaard–Oeschger scenarios, we discuss the possibility that oscillations of the deep-ocean conveyor may have been sufficient to cause this bipolar see-saw. The bipolar climate asynchrony in our scenarios is caused by the toggle between North Atlantic heat piracy and South Atlantic counter heat piracy. Ocean circulation has an enhanced sensitivity to the northern deep-water source as the North Atlantic Deep Water (NADW) cannot enter the Southern Ocean at depths shallower than the bottom of the Drake Passage. Any shoaling of the NADW can, therefore, increase the northward incursion of Antarctic Bottom Water (AABW), and trigger an interhemispheric climate oscillation. As hundreds of years are required to warm the respective high latitudes, the observed climate lead and lags between the two hemispheres can be explained entirely by the variability of the meridional overturning and by the corresponding change in the oceanic heat transport. Accordingly, it is entirely feasible for the global climate to work like a pendulum, which theoretically could be controlled by pushing at either of the deep-water sources. Our model scenarios suggest that it is entirely feasible for the bipolar climate see-saw to be controlled solely by variations in NADW formation. Copyright © 2001 John Wiley & Sons, Ltd.
James Cross says:
August 29, 2013 at 7:36 am
If there is no AGW, then I would expect it in 5-10 years, wouldn’t you say
====
Why would it be any different……normal uptics…when the overall trend is down
http://www.foresight.org/nanodot/wp-content/uploads/2009/12/histo3.png
rgbatduke says:
August 29, 2013 at 5:29 am
Going to have to disagree with you there: I can’t say that I’ve read every one of your replies the past three years, but I have missed very few.
You may have “been hammering on” this topic for a while, but, no, you have never expressed a summary of the fundamental problems with the CAGW models so thoroughly, so directly and so clearly as you have above!
Excellent and very effective explanation of the major points involved.
Great graph you got there, Latitude.
Numbers on the bottom, numbers on the side, and a squiggly line. No labeling of what the numbers represent (years and temperature, maybe?) or where the data came from.
James Cross says:
August 29, 2013 at 9:00 am
Great graph you got there, Latitude.
Numbers on the bottom, numbers on the side, and a squiggly line. No labeling of what the numbers represent (years and temperature, maybe?) or where the data came from.
===============
http://wattsupwiththat.com/2009/12/09/hockey-stick-observed-in-noaa-ice-core-data/
James Cross:
I am responding to your series of posts at
August 29, 2013 at 6:35 am
August 29, 2013 at 7:21 am
August 29, 2013 at 7:36 am
August 29, 2013 at 9:00 am.
The content of that series induces me to think you are attempting to divert the thread from its subject; i.e. you are trolling.
However, the first post in your series does slightly relate to the subject of this thread so I will address that with a view to avoiding further distraction from the subject.
Your post at August 29, 2013 at 6:35 am
http://wattsupwiththat.com/2013/08/28/another-paper-blames-enso-for-the-warming-hiatus/#comment-1402796
says in total
NO!
The lack of any discernible AGW provides no reason to assume we should “really be cooling” or that cooling will “start”, although it may.
The world has been warming from the Little Ice Age for centuries at a rate of ~0.8°C per century for centuries. The cause of this warming is not known but it certainly cannot be anthropogenic (i.e. from human) emissions of greenhouse gases.
There is no observed alteration of that warming from the LIA so it may be continuing. If so, then warming will resume until global temperature becomes similar to the global temperature of the Medieval Warm Period (MWP).
Can we now return to the subject of the thread, please?
Richard
The Cause that represses.