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Berkeley earthquake called off

Filed under: — eric @ 24 October 2011

Anybody expecting earthshaking news from Berkeley, now that the Berkeley Earth Surface Temperature group being led by Richard Muller has released its results, had to be content with a barely perceptible quiver. As far as the basic science goes, the results could not have been less surprising if the press release had said “Man Finds Sun Rises At Dawn.” This must have been something of a disappointment for anyone hoping for something else.

For those not familiar with it, the purpose of Berkeley Earth was to create a new, independent compilation and assessment of global land surface temperature trends using new statistical methods and a wider range of source data. Expectations that the work would put teeth in accusations against CRU and GISTEMP led to a lot of early press, and an invitation to Muller to testify before Congress. However, the big news this week (e.g. this article by the BBC’s Richard Black) is that there is no discernible difference between the new results and those of CRU.

Muller says that “the biggest surprise was that the new results agreed so closely with the warming values published previously by other teams in the US and the UK.” We find this very statement surprising. As we showed two years ago, any of various simple statistical analyses of the freely available data at the time showed that it was very very unlikely that the results would change.

The basic fact of warming is supported by a huge array of complementary data (ocean warming, ice melting, phenology etc). And shouldn’t it have helped reduce the element of surprise that a National Academy of Sciences study already concluded that the warming seen in the surface station record was “undoubtedly real,” that Menne et al showed that highly touted station siting issues did not in fact compromise the record, that the satellite record agrees with the surface record in every important respect (see Fig. 7 here), and that numerous independent studies (many of them by amateurs) also confirmed the warming trend?

If the Berkeley results are newsworthy, it is only because Muller had been perceived as an outsider (driven in part by trash-talking about other scientists), and has taken money from the infamous Koch brothers. People acting against expectation (“Man bites dog”) is always better news than the converse, something that Muller’s PR effort has exploited to the max. It does take some integrity to admit getting the same answer as those they had criticized, despite their preconceptions and the preconceptions of their funders. And we are pleased to see Muller’s statement that “This confirms that these studies were done carefully and that potential biases identified by climate change sceptics did not seriously affect their conclusions.” It’s far from the overdue apology that Phil Jones (of CRU) deserves from his critics, but it’s a start.

But Muller’s framing of the Berkeley results is still odd. His statement, that had they found no warming trend, this would have “ruled out anthropogenic global warming”, while true in a technical sense, would not have implied that we should not worry about human drivers of climate change. And it would not have overturned over a century of firmly established radiative-transfer and thermodynamics. Nor would it have overturned the basic chemistry which led Bolin and Eriksson (reprinted here) to predict in 1959 that fossil fuel burning would cause a significant increase in CO2 — long before the results of Keeling’s famous Mauna Loa observations were in. As a physicist, Muller knows that the reason for concern about increasing CO2 comes from the basic physics and chemistry, which was elucidated long before the warming trend was actually observable.

In a talk at AGU last Fall, Naomi Oreskes criticized the climate science community for being reluctant to take credit for their many successful predictions, so here we are shouting it from the rooftops: The warming trend is something that climate physicists saw coming many decades before it was observed. The reason for interest in the details of the observed trend is to get a better idea of the things we don’t know the magnitude of (e.g. cloud feedbacks), not as a test of the basic theory. If we didn’t know about the CO2-climate connection from physics, then no observation of a warming trend, however accurate, would by itself tell us that anthropogenic global warming is “real,” or (more importantly) that it is going to persist and probably increase.

Muller’s other comments do very little to shed light on climate change, and continue to consist largely of putting down the work of others. “For Richard Muller,” writes Richard Black, “this free circulation also marks a return to how science should be done,” the clear insinuation being that CRU, GISS, and NOAA had all been doing something else. Whatever that “something else” is supposed to be completely eludes us, given that these groups all along have been publishing results in the peer-reviewed literature using methods that proved easy to reproduce using easily available data (and in the GISTEMP case, complete code). In one sense, though, we do agree with Muller’s quote: nobody has stolen his private emails and spun them out of context to make his research look bad.

Laudably, Muller’s group have submitted their research to peer-reviewed journals, and the submitted drafts are available on their website. Amidst a number of verifications of already well-established results on the fidelity of the surface station trends, they also claim to have discovered something new. In their paper Decadal Variations in the Global Atmospheric Land Temperatures, they find that the largest contributor to global average temperature variability on short (2-5 year) timescales in not the El Nino-Southern Oscillation (ENSO) (as everyone else believes), but is actually the Atlantic Multidecadal Oscillation (AMO). This is pretty esoteric stuff, but it would actually be quite interesting if it were true — though we hasten to add that even if true it would have no significant bearing on the interpretation of long term temperature trends. Before anyone gets too excited though, they should take note that the basis for this argument is that the correlation between the global average temperature and a time series that represents the AMO is higher than for one that represents ENSO. But what time series are used? According to the submitted paper, they “fit each record [ENSO and AMO times series] separately to 5th order polynomials using a linear least-­squares regression; we subtracted the respective fits… This procedure effectively removes slow changes such as global warming and the ~70 year cycle of the AMO, and gives each record zero mean.” Beyond the obvious fact that if one removes the low frequencies, than we’re really not talking about the AMO anymore (the “M” in “AMO” stands for “Multidecadal”), one has to be rather cautious about this sort of data analysis. Without getting into the nitty-gritty technical details here, suffice it to say that Muller & Co are proposing a new understanding of global temperature variability, and their statistical approach is — at the very least — poorly described. There is a large literature on how to do this sort of thing, not to mention previous work on the AMO and its relationship to global temperatures (e.g. this or Mann and Park (1999) (pdf), among many others), which the Berkeley group does not cite.

Overall, we are underwhelmed by the quality of Berkeley effort so far — with the exception of the efforts made by Robert Rohde on the dataset agglomeration and the statistical approach. And we remain greatly disappointed by Muller’s public communications (e.g. his WSJ op-ed) which appear far more focused on raising his profile than enlightening the public about the state of the science.

It will be very interesting to see what happens to these papers as they go through peer review. No doubt, they will improve: that’s one of the benefits of the peer review process (suddenly popular again!). In the meanwhile, Muller & Co. have a long way to go before they can claim to be the best (as opposed to just the BEST). By launching his BEST project, Muller has no doubt ensured a place for himself in shaping the narrative on climate change science, but it remains to be seen to what extent he is going to contribute to the science of climate change.


208 Responses to “Berkeley earthquake called off”

  1. 101
    SecularAnimist says:

    David Miller wrote: “The planet will be fine if temperatures rise ten degrees.”

    If by planet, you mean the underlying ball of rock, then sure, the “planet” will be fine.

    But the Earth’s biosphere will definitely NOT be “fine” if temperatures rise 10 degrees. Indeed, the combination of a 10 degree temperature rise and the ocean acidification from the increased CO2 levels that a 10 degree rise implies, could very well lead to the mass extinction of most life on Earth.

  2. 102
    Ray Ladbury says:

    SirCharge,

    Wow, that’s the best skeptics have to offer, huh? Argument from personal incredulity. Dude, scholarly monks int eh dark ages recognized that as a logical fallacy.

    Hey, Party on, Dude. You must be smokin’ some good stuff.

  3. 103
    SecularAnimist says:

    tom wrote in #98: “A skeptic viewpoint”

    It’s good that you are visiting this site, because the “viewpoint” you describe is basically a statement of your ignorance of the state of climate science, what is known and unknown, what is certain and less than certain, etc. There is a wealth of information available here that can mitigate that ignorance.

    Assuming of course that you are here to learn something rather than merely to regurgitate false talking points.

  4. 104
    SecularAnimist says:

    barn E. rubble wrote: “If in fact ‘we’ are in control of the climate do we consider what’s ‘best’ for all regions globally?”

    What we are doing to the Earth’s climate cannot be described as being “in control” of anything. On the contrary, the basic problem is our uncontrolled massive CO2 emissions.

  5. 105
    Joe Cushley says:

    Re: Tom @98

    Erm. People say that RC is too heavily moderated, but recently quite a few people with a knowledge of the science ranging from zero to not-very-much, seem to be staggering in and relieving themselves in the punch-bowl…

    Back-up Tom, and start with the REAL 1) of the AGW theory. CO2 is a gas which absorbs infrared radiation, and we are pumping 30 Giga Tonnes of it into the atmosphere every year.

    Please press the Start Here button at the top of the home page, and come back when you’ve read a bit more on the subject.

  6. 106
    Dassin says:

    At Forbes.com James Taylor in an article titled “The Death Of Global Warming Skepticism, Or The Birth Of Straw Men?” quote mined this article yesterday.

  7. 107
    rob says:

    There is a nauseating comment from Fred Singer on the Nature Editorial ‘Scientific Climate’ (Nature 478, 428, 27 October 2011) re the BEST study. Missing from all of his credentials at the bottom of his meanderings, are the most important ones.

  8. 108
    pete mack says:

    The statistical technique has pride of place at the BEST homepage. If the error bars turn out correct, it’s a genuine tour de force: the apparent statistical power is 2x what it was in previous work.

  9. 109
    Brian Dodge says:

    “…we’re getting are a bit of natural cycle mixed with a century and a half of UHI.” SirCharge — 27 Oct 2011 @ 12:20 AM

    What UHI caused the 6000 year old Larsen B & Wilkins ice shelves to collapse into slush?
    Which ones have caused Greenland to lose 2000 gigatons of ice in 8 years?
    Did the Dallas-Fort Worth UHI set 3,944,707 acres of Texas on fire?
    Is it Resolute, Cambridge Bay, and Murmansk(total area ~500km2) UHI melting the Arctic summer ice cover, from 7.4 milliom km2 1980-1985 to 4.8 million km2 2007-2011?
    Which UHI is responsible for the record setting decade of drought in Australia?

  10. 110
    dhogaza says:

    Dassin:

    Well, the same issue proclaims:

    “Fundamental Tax Reform Is Now Unstoppable” (by which they mean some version of a flat tax which will shift more of the tax burden to the middle class and poor, I’d say the claim is overly optimistic)

    “Recreating A Real Gold Standard” – yeah, putting the US on the gold standard will help our global competitive position, uh-huh. It won’t happen until after we enter the next ice age, which, if we keep doing what we’re doing, might not happen at all …

    “Flat Tax This: Regulations Are the Boot On Hiring’s Neck” – oddly these same regulations were in place during the Big Bubble …

    Grown-ups don’t pay attention to Forbes.

  11. 111
    dhogaza says:

    Dassin:

    Thanks for the link, because this is hilarious:

    Very few if any skeptics assert that the earth is still in the Little Ice Age. While the Little Ice Age raged from approximately 1300 to 1900 AD, it is pretty well accepted that the Little Ice Age did indeed end by approximately 1900 AD.

    1900 … har har.

  12. 112
    Russell says:

    Watts has responded to the Nature editorial leader with the utterly bogus claim that

    Nature printed this letter from Dr. Fred Singer, which I was also given a copy of via email:

    Fred Singer said:
    Dear Editors of Nature:
    What a curious editorial [p.428, Oct.26} ? and how revealing of yr bias!
    “Results confirming climate change are welcome, even when released before peer review.”
    (emphasis added)
    You imply that contrary results are not welcomed by Nature. But this has been obvious for many years.

    Why are you so jubilant about the findings of the Berkeley Climate Project that you can hardly contain yourself? What do you think they proved? They certainly added little to the ongoing debate on human causes of climate change.

    The rest of Singer’s screed can be read on Watts site, but since the’ Scientific Climate ‘ leader it replies to appears in Nature vol. 478, page 428 (27 October 2011) only superluminal typesetting could have seen it ‘printed’ in the same issue.

    It didn’t happen, though Singer has violated both Nature’s strictures against science by press conference, and the very principle he pretends to defend , by giving it to Watts to publicize

  13. 113
    SirCharge says:

    “then go to Skeptical Science, where there are nearly 5,000 threads dealing with the skeptics memes you propagate.”

    I’ve been there and don’t disagree with most of what is written. The site does, however, have a tendency to pretend that all matters have been settled and there is no room for discussion. An egregious example of this is the section on UHI. The author uses the paper Jones (2008) as his evidence that UHI is a nonfactor. The problem with this is that Jones 2008 actually found that UHI caused a 0.1 degree celsius temperature increase per decade and a 0.5 degree celsius increase total over the time period (see http://www.agu.org/pubs/crossref/2008/2008JD009916.shtml) For some reason skeptical science manages to omit this rather significant tidbit.

    @caerbannog
    “Yes, all of this will take a fair bit of time, and may be painstaking and tedious. That’s why they call it “work”. And “work” is exactly what you need to do if you have any hope of making a credible case for your UHI claim.”

    I would love to do so. Unfortunately I have a job and family. My question is, why would I need to go through that effort? Shouldn’t there be a host of papers written by climatologists on the topic which use very similar methods to what you just described? (Please don’t bring up Peterson’s papers as an example of this as he doesn’t know the difference between rural and urban). The only papers that I can find are written by skeptics. Feel free to point out an example of studies that I may have missed. It seems to me that climatology does not regulate itself very well.

    @Brian Dodge
    You missed the point where I indicated that we are in a warming trend that is part of a natural cycle. Yes, we are breaking records in part because of local variability of the weather, in part because we just concluded a warming trend and in part because we are experiencing a la nina event/cool pdo as well as a change in the arctic oscillation and wind patterns. In addition I do not doubt that there is some small segment of the warming related to AGW. What is not plausible is the notion of an enhanced AGW.

  14. 114
    JCH says:

    Curious if anybody has looked at this. To which temperature series is the BEST result closest?

  15. 115

    #104–Yep. The closest automotive analogy to our collective situation is that we are in a car with no steering and our accelerator foot trapped in the ‘full on’ position.

    Not exactly “in control”–though some of us are at least trying to figure out where the brake pedal is.

  16. 116
    Tom Dayton says:

    SirCharge, you have misread the Jones paper, which does not attribute 0.1 celsius to UHI. Even if you read only the abstract you would see the clear statement that the total warming in urban sites–not the urban heat island effect portion–was 0.1 degree, with the “true climatic” portion being nearly all of that–0.81 degree out of the total 0.10 degree.

  17. 117

    @ SirCharge

    The site does, however, have a tendency to pretend that all matters have been settled and there is no room for discussion.

    Yet another skeptic meme to avoid dealing with hard facts.

    An egregious example of this is the section on UHI.

    If you feel there is a problem with an article on Skeptical Science then post a comment on the relevant thread with supportive citations. All you are doing here is baseless handwaving.

    For some reason skeptical science manages to omit this rather significant tidbit.

    Nice imputation of impropriety. Again, without supportive citations, yet more handwaving.

    The readership of this blog is more than sufficiently educated on the science to be taken in by your sophistry and dissembling. Not to mention the overlarge Dunning-Kruger streak you display.

    I gave it a shot, RC, but there is no reasoning with a closed mind.

  18. 118
    Ray Ladbury says:

    SirCharge, You are ignoring that temperatures are corrected for UHI. You are also ignoring that rural stations show the same trend as urban–and that the greatest warming is observed in the far north–where there are no major urban areas.

    Natural trend? Dude, do you really think natural fluctuations produce 40+ year warming trends. And if it is not due to fluctuations, then there is that pesky first law of thermo that asks where the energy comes from.

    Do you know tht “denial” is not a river in Africa?

  19. 119
    Joe Cushley says:

    Sircharge @ 113

    “The problem with this is that Jones 2008 actually found that UHI caused a 0.1 degree celsius temperature increase per decade and a 0.5 degree celsius increase total over the time period (see http://www.agu.org/pubs/crossref/2008/2008JD009916.shtml) For some reason skeptical science manages to omit this rather significant tidbit.”

    I’ll tell you what the problem is, the problem is you have distorted this cite horribly. This is with reference to CHINA, CHINA! China has experienced rapid urbanization and dramatic, to say the very least, economic growth in this period. You may even have read about this, and about how some scientists believe that the contribution of aerosols as a result of explosion may have contributed to the relative slow-down of global warming of the last few years.

    http://www.pnas.org/content/108/29/11790.abstract?sid=75d97da2-a6f1-41df-9069-483e3acc5d3b

    To coin a phrase – for some reason Sircharge manages to omit this rather significant tidbit…

    “Unfortunately I have a job and family.” Gosh, that’s great. I’ve always wondered what it must be like to have those. Oh wait. I *have* got a job and a family. As I imagine many folks here have. You evince a very low level of research in your posts and job and family are just not good enough excuses.

    There’s more…

    “I indicated that we are in a warming trend that is part of a natural cycle…”

    vs

    “we just concluded a warming trend” This is a laughable statement on so many levels.

    The Dunning-Kruger is strong in this one…

  20. 120
    caerbannog says:

    SirCharge

    I would love to do so. Unfortunately I have a job and family. My question is, why would I need to go through that effort? Shouldn’t there be a host of papers written by climatologists on the topic which use very similar methods to what you just described? (Please don’t bring up Peterson’s papers as an example of this as he doesn’t know the difference between rural and urban). The only papers that I can find are written by skeptics.

    (The tradition of deniers producing excuses instead of results continues…)

    OK, then where are the papers written by skeptics that directly compare rural vs. urban global-average temperature results? I laid out a procedure that would take no more than a few man-days of effort to produce preliminary rural vs. urban results. Why haven’t any skeptics done this? I mean, “skeptics” have been making claims about UHI for *years* — as for all the “skeptics” who boast of their scientific credentials, why haven’t any of them been able to expend a few man-*days* of such effort in all of the *years* that they have been complaining about UHI?

    Ditto for Watts’ dropped stations claim — testing that claim would take no more than a few *man-hours* of effort once you have a basic gridding/averaging program up and running (NASA/GISS and Clear Climate Code already provide that code-base). Seriously — starting with what’s already available on the Internet, such an project would require that little effort. So where are the skeptical papers that show the impact of “dropped” stations on global-average temperature results? I mean, where are the papers that show “dropped stations included” vs. “dropped stations excluded” results side by side?

    So SirCharge, we are looking at analysis projects that deniers have should have tackled *years* ago to verify their claims. These projects should require man-*hours* to man-*days* to complete (given that most of the “heavy lifting” has already been done by NASA, Clear Climate Code, etc.). Yet in the *years* that deniers have been making these claims, not one of them has expended even this minimal amount of effort to test said claims.

    SirCharge, let me remind you that it has been *skeptics* that have been making the above claims — it is up to said *skeptics* to publish papers demonstrating the validity of those claims. So in all these years, why hasn’t a single skeptic published any papers that do so?

  21. 121
    Pete Dunkelberg says:

    More from Tamino on the BEST AMO paper: Decadal Variations and AMO — Part II.

  22. 122
    SecularAnimist says:

    SirCharge wrote: “I indicated that we are in a warming trend that is part of a natural cycle”

    That’s a falsehood no matter how many times you “indicate” it.

  23. 123

    Eric,

    Thanks for this, which I’ve been waiting for.

    Their central rationale appears to be that CRU were wrong to “hide” their data (a flimsy accusation) and hence the results had to be checked. This has already been done by the Muir Russell enquiry and of course the various other independently-derived data sets that are consistent with CRU. Same with the stuff about checking weather stations.

    They have found that everyone else in fact did their jobs pretty well, and somehow found this surprising. Do they think we are all dolts?

    What I find objectionable about the whole exercise is the accompanying innuendo. This stuff all has the nasty stench of the tobacco industry wanting the probability of causing cancer to be calculated to ever more precision, when they knew themselves that they were selling a flawed product. Muller et al. are guilty of buying the denial case time, rather than ultimately supporting it, and you have to ask: who gains from that? Rather than the moral high ground they are trying to occupy, their motives are suspect, and border on unethical. Like medical scientists who took money from tobacco companies, they do not deserve to be taken seriously.

    One of the key political arguments by deniers is that scientists are in it for the money. So why was this relatively well-funded and ultimately useless study, funded in part by the denial industry, necessary? The real money should be going into the hard problems of renewable energy, not into confirming what we already know, and what we should be trying to prevent.

  24. 124
    Rattus Norvegicus says:

    An 8.O on the BS meter is about to hit courtesy of the GWPF:

    http://www.dailymail.co.uk/sciencetech/article-2055191/Scientists-said-climate-change-sceptics-proved-wrong-accused-hiding-truth-colleague.html

    [Response: Well let's see if we can follow the shells here. The BEST team's research goal was to validate whether or not the data sets used in other global T analyses were biased. Having found that no, they are not, Curry has now decided to change the focus to the more or less completely unrelated question of whether there's been any upward trend over the last decade. Oh OK.--Jim]

  25. 125
    MikeAtkinson says:

    Well, that did not take long

    “Scientist who said climate change sceptics had been proved wrong accused of hiding truth by colleague”

    http://www.dailymail.co.uk/sciencetech/article-2055191/Scientists-said-climate-change-sceptics-proved-wrong-accused-hiding-truth-colleague.html

  26. 126
    Stephan says:

    For info, if anybody thought that this will settle the issue in the media – no, it will go on:

    http://www.dailymail.co.uk/sciencetech/article-2055191/Scientists-said-climate-change-sceptics-proved-wrong-accused-hiding-truth-colleague.html
    (Warning: Reading the Daily Mail may permanently damage your mental health. Approach with caution).

    Judith Curry is obviously angry that she didn’t get to read Muller’s press release before it went out, but I can’t work out what her point is regarding the analysis. She’s co-author of the papers, so does she reject her own papers here? The article is completely muddled and confused but it will again just leave the readers with the impression that climate science is completely dodgy.

  27. 127
    Marco says:

    To those pointing to the Mail, please note the journalist: David Rose is a serial distorter in the climate debate.

    [Response: As if Curry isn't?? ]

    Curry has already backtracked quite a bit on her own blog.

    [Response: Why did she have to "backtrack" on anything in the first place?--Jim]

  28. 128
    Ray Ladbury says:

    Ah, just the sort of clarity and investigation I’ve come to expect from the Daily Fail. And just the sort of equivocation and vagueness, coupled with insinuation, we’ve all come to expect from Judy. Why does anyone take either The Fail or Judy seriously anymore?

  29. 129
    Pete Dunkelberg says:

    > Why does anyone take either The Fail or Judy seriously anymore?

    There is a reality oriented community and there is a reality disoriented community with an entire alternate “reality.” Example:

    http://www.climatesciencewatch.org/wp-content/uploads/2011/09/The-Real-Truth-About-Greenhouse-Gases-and-Climate-Change_1.pdf

    But you knew that.

  30. 130
    Louise says:

    The Daily Mail is not noted for its accuracy

    http://www.youtube.com/watch?feature=player_embedded&v=5eBT6OSr1TI

  31. 131
    JCH says:

    Using Wood for Trees, I made (I think) a graph of the last 120 months.

    So in this month-to-month scoring, has AGW resumed?

    [Response: As we've said many times, short term trends are not useful for such statements. But one thing worth noting is that in the BEST error estimates, the errors for the last few months are an order of magnitude larger than for the other months and that the big dip right at the end is very likely not real. I imagine it is related to a very limited data coverage in their 2010 collation. - gavin]

    [Further response: Tamino has observed the same thing. -gavin

  32. 132
    Marco says:

    Gavin, Tamino put up a good post on Curry’s ignorance.

    Jim, after having read the thread and Curry’s comments in it, I concur.

  33. 133
  34. 134
    Chris R says:

    JCH,

    Tamino shows that the warming hasn’t stopped even by the Berkeley dataset. See here.

    There are no grounds for claiming global warming has stopped.

    Judith Curry is simply wasting people’s time and really should know better. Although the pattern w.r.t. her musings indicates she simply doesn’t like the idea of AGW and that is clouding her better judgement.

  35. 135
    dhogaza says:

    Marco:

    Tamino put up a good post on Curry’s ignorance.

    Oddly, her certainty is untempered by uncertainty …

  36. 136
    Mike Roddy says:

    Curry is damaging the public discourse, and few who read her statements bother to go to RC to find out what the science says, which is generally the opposite of whatever she is saying to the media.

    I’d be interested in RC people’s theories about what in the world happened to Judith. She now believes McIntyre and Watts more than just about any scientific peer.

    Behavioral science is definitely one of the soft ones, but someone should be able to shed some light here.

  37. 137
    mps says:

    With the Daily Mail article (and Judith Curry’s contribution to it), Muller is learning what climate scientists have to put up with every day (I am not one myself, but I can only imagine). I wonder if it will make him more careful about his own criticisms in the future…

  38. 138
    flxible says:

    Behavioral science is definitely one of the soft ones, but someone should be able to shed some light here.

    I believe it’d take some one from a biomedical science to explain it.

  39. 139
    dhogaza says:

    Mike Roddy:

    I’d be interested in RC people’s theories about what in the world happened to Judith.

    She saw an out that was congruent to her political leanings.

    I challenge anyone to put forward a more compelling hypothesis.

  40. 140
    Brian Dodge says:

    @ SirCharge
    Even if it were natural variations, it would be incorrect to say “a natural cycle”. As you pointed out, for starters we have ENSO, PDO, and Arctic Oscillation – three natural cycles – plural. If you want to describe them mathematically as oscillations, you have to include randomly variable frequency and amplitude modulations. Then you have to take into account the variable frequency and phase of the solar cycle, and the delay in response to any forcing you could produce cause by the thermal mass and nonlinear response of the separate components of the cryosphere. The time constants of albedo feedback from melting N America snow cover are shorter than the albedo feedback from melting Arctic sea ice, and the sea ice is changing response as its average thickness decreases, and the ratios of 1, 2, 3, 4, 5 year ice area changes. Arctic sea ice is less than ten meters thick; the floating ice shelves are several tens to hundreds of meters thick; the Canadian Arctic Alfred Ernest Ice Shelf, Milne Ice Shelf, Ward Hunt Ice Shelf and Smith Ice Shelf are less thick than the Antarctic ice shelves, and the Ayles Ice Shelf and Markham Ice Shelf broke up in 2005 and 2008. Even in the Antarctic, the much larger Larsen A and B shelves, the Wordie, Jones, and Muller shelves, and a significant part of the Wilkins ice shelf have recently broken up in highly nonlinear “tipping point” events. Larsen B was ~220 meters thick, and an area about the size of Rhode Island broke into small fragments in less than thirty days. The Greenland and Antarctic ice sheets have much larger masses and consequently much longer time constants, but there is already observational evidence of nonlinear response. Mass loss from glaciers determined by the WGMS is also accelerating – http://www.wgms.ch/mbb/sum09.html

    In “Cyclic Climate Changes and Fish Productivity” K.B. Klashtorin and A.A. Lyubshin found spectra of ice cores and tree rings showed peaks at 25.6, 32, 32.5, 38.6, 53.9, 55.3, 60.2, and 75.8 year periods. They go on to say “Fluctuation spectra of California sardine and anchovy populations during the recent 1700 years (Fig. 1.15) demonstrate well defined predominant peaks: 57 and 76 years for sardine and 57, 72, and 99 year for anchovy. This correlates well with the predominant spectra of climatic fluctuations during the last 1500 years according to ice core samples and tree growth rings.” Plus there are DeVries–Suess and Gleissberg cycles with periods near 210 and 87 years, and A 725 yr cycle in the climate of central Africa during the late Holocene, J.M. Russell, T.C. Johnson and M.R. Talbot, Geology, v. 31 no. 8 p. 677-680. (BTW, the last peak in the cycle was ca. 400 years ago, an is therefore out of phase with the current warming by 325 years).

    In Possible solar origin of the 1,470-year glacial climate cycle demonstrated in a coupled model, Holger Braun, Marcus Christl, Stefan Rahmstorf, Andrey Ganopolski, Augusto Mangini, Claudia Kubatzki, Kurt Roth & Bernd Kromer postulated that the combination of the 210 year DeVries–Suess and the 87 year Gleissberg cycle could tip nonlinear fresh water influxes and subsequent changes in Thermohaline Circulation triggering Dansgaard-Oeschger events.

    If we take an epicyclic periodic leap of faith an assume the hypothesis that this 1470 year cycle is a significant driver of present day warming, and align it with the Medieval warm period, we get temperatures rising from ~800 BC to a warm peak at ~468 BC – a little early for the Roman warm period. Temperatures then fall through 100 BC to a minimum at ~267 AD(and associated bad weather starts the tribal migrations that soon lead to the fall of Roman Empire), rising through 635 AD to the MWP peak at 1002 AD. Temperature then head back down through 1370 AD to the LIA minima around 1737. then temperatures begin rising again. What is the probability that all the other periodic natural variations observed just happen to be in the correct phase and amplitude to coincidentally match anthropogenic carbon emisions?

    And of course if we extend the 1470 year cycle forward, temperatures will be rising through 2105 to a peak around 2473. Adding the 1.23 degree OLS rise seen in the BEST record since 1800 to an expected 2.46 degrees(ignoring the accelerating slope of the record in recent decades) to the peak gives 3.69 degrees – “catastrophic natural warming?”

    “Periodic” is often used to describe systems that have two reactive(where the response is out of phase with the forcing) components; inductor and capacitor in electronics, mass and spring in mechanical clocks, chemical bond and atomic mass in greenhouse gases, gas density and compressibility in sound. In climate, the apparent periodicities arise from noisy forcings(turbulence, high and low pressure vortices, ocean surface water sloshing back and forth or surface currents and Eckmann transport, convection, etc.) being filtered into bands by lossy mechanisms (wind friction and turbulence, thermal conductivity, AMO circulating currents, isotropic scattering and emission).
    As the wikipedia entry on Bond events says, “…the 1,500-year cycle displays nonlinear behavior and stochastic resonance.”

  41. 141
    Brian Dodge says:

    “This graph shows that the trend of the last decade is absolutely flat, with no increase at all – though the levels of carbon dioxide in the atmosphere have carried on rising relentlessly.

    ‘This is nowhere near what the climate models were predicting,’ Prof Curry said. ‘Whatever it is that’s going on here, it doesn’t look like it’s being dominated by CO2.’

    Climate models generate “noise” from various processes like ENSO, and do in fact generate 10-15 year periods with no significant temperature increase despite rising CO2.

    BEST shows -
    0,003 deg/y since 2001
    0.0176 deg/y since 2000
    0.0324 deg/yr since 1993

    Is Curry that effing stupid, willfully uninformed, or just outright lying?

  42. 142
    Nick gotts says:

    I’ve heard on BBC Radio 4 that Judith Curry is now giving a denialist spin to the outcome of the BEST study! Apparently, there’s been no warming since the late 1990s. Muller was cited as agreeing, but saying this “may or may not be statistically significant”. Now the broadcasters may have garbled the message, but this does sound like complete piffle based on looking at a period too short for the trend to reach significance – and simply (like the AMO stuff?) an attempt to distract attention from the study’s remarkably close confirmation of others’ results.

  43. 143
    Nick Gotts says:

    Ah, that last comment is rather out-of-date – I didn’t notice until just now that it hadn’t been sent, and sent it without reading the latest comments from others.

  44. 144
    Tom Dayton says:

    Refreshingly, at least one newspaper was blunt: The San Francisco Chronicle’s editor yesterday wrote in the editorial page:

    Richard Muller, UC Berkeley physicist:
    He believed: The science behind climate change was shoddy and politically driven.
    He discovered: He was wrong.

  45. 145
    JCH says:

    From Judith’s Curry’s recent discussion with Richard Muller:

    With regards to the BEST data itself and what it shows. He showed me an interesting graph this is updated from the Rohde article, whereby the BEST data shows good agreement with the GISS data for the recent part of the record. Apparently the original discrepancy was associated with definition of land; this was sorted out and when they compared apples to apples, then the agreement is pretty good. This leaves CRU as an outlier.

    Speaking of CRU, Muller related an interesting anecdote about Phil Jones that was apparently related to him by a reporter. When Jones was asked to comment on the BEST papers, he said he no comment until after the papers were published. Maybe Muller was correct in worrying about making sure the IPCC pays attention. … – Judith Curry

    To what about CRU is the IPCC supposed to pay attention?

  46. 146

    There was nothing new or surprising in Richard Muller’s work. His main concern was that there was not enough skepticism prior to ‘his’ work? It is a bold claim and I am reasonably sure that most of the scientists that have been working in the field would argue with him on that point.

    Essentially he was saying that because ‘he’ was not convinced until ‘he’ examined the data that ‘he’ would not believe the other scientists.

    There is no revelation in his work though. Global warming was predicted as early as 1896 by Svante Arrhenius and further confirmed through the work of many scientists over decades of research including Callendar, Plass, Revelle, Keeling, Hansen, and in recent decades thousands of scientists and hundreds of research universities and institutions.

    Muller only confirmed, that the world is warming though, he did not delve into the human cause issue. He may still be skeptical but did say “Greenhouse gases could have a disastrous impact on the world,” he said. Yet, he contends that threat is not as proven as the Nobel Prize-winning Intergovernmental Panel on Climate Change says it is.

    What this indicates is that he does not trust the field of science until he personally verifies it. It’s odd though. He knows the scientific method is being used in climate science. It seems he merely does not trust the work of others. My question then to Richard Muller is, does he fly in airplanes or if he does, does he ask the pilot to let him fly the plane so that he knows everything is being done correctly.

    His statements still lean toward arrogance and his skepticism seems inappropriate as it seems overly skeptical of the very foundations of science itself.

    It seems strange that the quality of so many thousands of scientists could not be trusted until Richard Muller could put his stamp of approval on it. This fact remains. The basic physics knowledge of the greenhouse effect have been examined since 1824 beginning with Joseph Fourier, the hypothesis that we should warm with continued CO2 emissions has been around for more than a hundred years, the general confirmations and realization that this will develop into a global problem have been germinating for over 50 years, and in the last three decades the knowledge that the warming we will experience will affect our climate and agricultural systems is well known.

    Muller has added nothing new to his understanding other than inform us that there are still some stubborn scientists that don’t believe anything until they see it with their own eyes. I conclude with this thought. There is healthy skepticism and there is arrogant skepticism. The evidence suggests that Richard Muller falls into the arrogant skepticism side of the equation.

    In summary, if nothing scientific can be trusted until Richard Muller tests it, then he’s going to be a very busy man.

  47. 147

    “In summary, if nothing scientific can be trusted until Richard Muller tests it, then he’s going to be a very busy man.”

    Well, he hasn’t been so busy that he couldn’t speak to the press.

  48. 148
  49. 149
    Jim says:

    Everybody please knock it off with the off topic pontifications about crop yields and stick to the topic of this article. All such comments have been deleted. No more on it please. Thanks.

  50. 150
    GlenFergus says:

    On a quick look, the most significant contribution here looks to be the data manipulation of Rohde et al alluded to in the Eric’s post. Particularly the spatial averaging approach adopted might reasonably be expected to deliver a better treatment of sparse early data, and so perhaps a better – and rather cooler – estimate of 19th century temperatures. If so, the most significant Berkeley contribution might actually be to substantially increase the best estimate of warming since pre-industrial times.


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