Repower America

Aloha.
After a long absence, I am back blogging for a minute. Essentially, I have refrained from participating in the blogosphere, in favor of the postdoctoral research I am actually employed for, writing a book on week-ends, and visiting family in Europe. I have also looked at Climate Audit a few times, only to be shocked that the herd of barking dogs has gotten way out of hand to be worthy of my time. Until the next idiocy calls for a spanking…

I was tempted to blog a few weeks ago about an utterly gruesome article that was the front page of a newspaper I would be reluctant to wipe my bottoms with, The sunday paper. The front page touted “Is Gore wrong ?”, while the story was largely about a tiny rally of anti-AGW nuts still stuck in 50’s McCarthyist rhetorics. Essentially, trying to curb greenhouse emissions was a “socialist” move, and the wackos celebrated their inalienable right to use to incandescent light bulbs by flying a hot air balloon : swift, to say the least. The offensive part wasn’t so much the tone of the article, which actually also gives space to the pro-AGW side (albeit not to its most credible defender, IMHP) ; the offensive part indeed was the editorial spin of the front page headline, insidiously suggesting that all of the climate crisis is bogus because of an insignificant event that gathered a few misguided armchair skeptics.

I clearly have a long way to go on the road to climate communication, because just re-reading this article heated my blood a tad too high, and made me wish I had a few nitwit ballooners around, just to strangle them à la Bart Simpson. That is why I stayed silent then. Yet, the Sunday Paper mishap did not go unnoticed, and a moderate commentary of it can be found here. I would certainly have been way more incisive, but preferred to calm down in the face of some obvious facts :

1. Anger never solves anything.
2. Too few people read the Sunday Paper for this to be of importance.

So I waited until something more positive came along, which happened just a few days ago.

On July 17, the inevitable Al Gore delivered an inspiring address at D.A.R. Constitution Hall in Washington, D.C, hosted by the WE campaign. Gore challenged U.S. policymakers, entrepreneurs, and ordinary citizens to change their entire approach to energy use. He proposed that the U.S. produce all of its electricity using carbon-free energy sources by 2018.

To those afflicted by the Gore Derangement Syndrome : this will be extremely offensive material. To others, I think it gives an excellent example of a forward step out of the triple crisis we are currently in : economic, energetic, environmental.

Power quote :

“We are borrowing money from China to buy oil from the Persian gulf, to burn it in ways that destroy the planet. Every bit of that has to change”.

Since nothing seems to happen these days without McCain’s or Obama’s commentary, no one should be surprised that they reacted to it ; what’s more surprising is that they agreed about it. McCain apparently said, “If the vice president says it’s doable, I believe it’s doable.” [Source: Associated Press]. Obama’s praise was even higher.

As I have said before, I am not here to endorse a party, but I am pleased that both presidential candidates can hear the voice of reason. It makes me hopeful that this is not a lost cause, whichever the outcome of the November election.

It remains to be seen how many key players do get on board. I surely hope not too many of them are flying hot air balloons instead of getting busy, because that would be grounds for practicing slingshot in Marietta, GA.

El Niño and the end of the world

Aloha,

it’s has been a while… I have been traveling relentlessly (New York, Paris, London, Los Angeles, Vienna) and haven’t found much time for blogging. I have a few posts on the back burner, which need more research (what doesn’t, really ?).

Of course I don’t have any more time today, but I just remembered this student paper on El Niño, sent by a friend some time ago. (see gif file)

I have no idea where it came from and could not trace it back, but I could not resist posting it. I hope “Jeremy” won’t mind that his prose gets to the WWW - it is utterly priceless . It is given here just for laughs, to find at least some comfort amidst the current food crisis.

To those who think journalists can be overzealous in their climate alarmism, beware of the next generation !

MIT’s Susan Hockfield on the Global Energy Challenge

I thought I would share some opening remarks of MIT president’s Susan Hockfield, given last week at the annual meeting of the American Academy of Arts and Sciences.

With all the fossil fuel denialism out there, it’s sometimes good to remember that some world science leaders have their priorities straight : free access to knowledge, research in renewable (and scalable) energy, efficiency and sustainable development.

Her address can be found here in RealVideo format. (< 15 min)

The Heisenberg Principle of Climatology

OK, I have to admit this is a pretty eccentric idea . It occurred to me around New Year’s time. Please read this as entertainment, not science - or at best, entertaining science. I assume the esteemed reader to be familiar with Heisenberg’s uncertainty principle .

These days, even small-time lawyers are using the concept - as we were reminded by the Coen brothers in the magnificently quirky “The Man who wasn’t there” :

Forgetting the Coen twist, the uncertainty principle states that there is a fundamental limit to the accuracy with which you can jointly determine the position () and the momentum () of a particle in quantum world. Which one can write :

wherein is the root mean square operator and is the familiar Planck’s constant.

This has pretty deep philosophical implications because it means that we must abandon utopias of ever knowing those quantities simultaneously with arbitrary accuracy. Most sobering is that it is a direct consequence of the fundamental principles of quantum mechanics.

It occurred to me the other day while having a shower (which is a well-known fountain of ideas), that one could formalize a similar principle in climatology. Indeed, the basic curse of paleoclimatology is that the farther back in time you try to estimate temperatures, the more uncertain they become. We think we know last year’s globally average temperature pretty well (say within 0.05 C ). Last decade might have similar or even lower uncertainties because of the central limit theorem knocking down some measurement errors for you… but try going back 100 years and the measurement error and sampling bias become so large you’ll be lucky to have an accuracy of 0.5 C. And that is during a period broadly known in the field as “instrumental”, that is to say the one over which we have a reasonable number of physical measurements of temperature. As you can see on the following graph from Brohan et al, 2006, this uncertainty grows back in time rather quickly already.

Before about 1850 A.D., we no longer have enough direct measurements, so we have to rely instead on proxy indicators. All of them (corals, tree rings, ice cores, sediments, documentary evidence) have their pros and cons, but even if they can give a surprisingly coherent view of past climates, they are necessarily approximate. Hence, go back 1000 years and arguably, we don’t know this within 0.7 C, perhaps even 1 C (this is a very controversial number and I’d be surprised if no one picks up on it… With wacky ideas come rather loose numbers that one should not take too literally). Go back 10,000 years and a degree C or two might be all that you could hope for. And so on and so forth : the more time elapses and eons pass by, the more water flows under bridges, the more overprinted, worn and tired is the geologic record - and so grows the uncertainty in the estimated temperature.

Say you are trying to estimate said temperature, , over some period (or equivalently, the frequency ). The longer the period (i.e., the smaller the frequency), the more uncertain the estimate, so one could write something of the form :

.

Which is pretty naive and assumes an inverse relationship between the two variables, and is by no means a “universal” constant. More generally one could write :

where the subscript denotes a reference period (say, the last decade), and and are a positive constants, whose precise values are as yet undetermined. So one could play games with that and try to estimate them from a linear fit in log-log space… I’m not sure they would mean much, but who knows ? Perhaps one day we’ll have enough reliable data to be able to characterize this and it won’t seem so quirky. In any case, it’s now pretty far from Heisenberg, who must be shifting in his grave and the mere idea that I am using is august name for such silliness. Nevertheless, it is an uncertainty principle of sorts. And for no more fundamental reason that the degradation of geological records over time, which I guess one could view as a broad consequence of disequilibrium thermodynamics. But only loosely so, because bioturbation holds a large part of the blame, and darned if we have a consistent theory of living organisms that’s grounded in statistical mechanics. But I digresss.

In my defense, I would like to declare that this nonsense was scribbled on a piece of paper while leaning on a garbage can outside the Metropolitan Avenue subway station in Williamsburg, Brooklyn. Which we all know to be home to some pretty crazy stuff.

Now here’s the truly insane part of the story. The next day was my adoptive bigger sister’s birthday. ( If you happen to live far from home, I highly recommend you adopt, or get adopted by, a bigger sister. It’s loads of fun, especially when they have the same linguistic schizophrenia as yours). I was working from the Columbia University library that day, and decided to drop by to bring her a gift (she lives around the corner). I had no sooner entered her building and stepped into the elevator that a white-haired gentleman nimbly entering the lobby asked me to hold the doors. I happily obliged, and he promptly jumped into the cage a few seconds afterwards, with a mischievous smile on his face.

- “Piso cuatro, por favor “, he said with a distinguished Spanglish accent.

- “Si señor”, I replied, and pushed button 4.

He looked at me from top to bottom and asked in a spotless New England English (I must have looked really freaky) :

- “Are you a physicist ?”

- “Almost”, I replied, “I’m a geophysicist”.

- “Ah well, I am a physicist”, he went on. “And I recently had a very interesting epiphany about Heisenberg’s uncertainty principle.”

 

Before I could pick up my jaw from the floor, Mr Heisenberg Jr had disappeared into the depths of the 4th floor, only perceptible through the rustling of his raincoat as his walked down the corridor. And so it was decided that even though my Heisenberg idea might not pass into posterity past breakfast, it should at least be worthy of a little post.

 

 

 

Happy Waits Year

It is only a few days into this new year : a perfectly opportune moment to celebrate its inception. And to wish all my dear readers (the whole half dozen of them) a great coming year.

This one started on blissfully auspicious terms for me, so i’ll stick to one wish : see Tom Waits live sometime soon. Because, as much a this blog is about climate, let’s face it : there are more important things in life - like Tom Waits.

I am now in New York, and how fitting is it i stumbled upon this interview today ?

in which one can hear what instantly became my favorite NYC quote :

Q : Tom, how would you describe New York City ?
A : Well, it’s like being on a ship, you know. And the water is on fire…

I have a direct view on the Empire State Mast as we speak, looking down on the sea of freakers that is Union Square, and i have to say he’s damn right. As always.

Anyway, more to the point of this blog, which is named after a song from the master : i have taken up to documenting Mr Waits’ meteorological musings. I engage all the Tom Waits fans around here (i know there are a few) to pop in and point out all those that have escaped my attention.

So far i counted :

- Blue Skies [The Early Years] (1971)

- Diamonds on my windshield [The heart of Saturday night] (1974)

- Shiver me timbers [The heart of Saturday night] (1974)

(thanks to Scotopia)

- Emotional Weather Report [Nighthawks at the diner] (1975)

- Rain dogs [Rain Dogs] (1985)

- Cold Cold Ground [Frank's Wild Years] (1987)

- Strange Weather [Big Time] (198

- A Little Rain [ Bone Machine] (1992)

- November [The Black Rider] (1993)

- There’s only Alice [Alice] (2002)
(thanks to ICE for pointing it out)

- Make it Rain [Real Gone] (2004)

So I wish you all a great 2008. Listen to Tom Waits, keep the carbon footprint low, do good whenever you can and the world will be a better place.

Lively Feed from AGU

Salut tout le monde,

As anyone in this field who is lucky enough to have travel funds, i am now enjoying a very exciting weeks at AGU, or for those not in the jargon, at the annual Fall meeting of the American Geophysical Union.

If you’ve watched RealClimate and ClimateAudit in the past view days, you’ve seen that sharing notes about various sessions seems a popular hobby.

I will refrain from this here ; being notoriously hard to please, there are only a few talks each day that i would deem post-worthy anyway - though i have to say i have already heard many a good talk this year. It is a refreshing change from last year, when somehow i always made bad enough choices to fall into a deeply soporific session.

So… it is EXCITING. The San Francisco weather, usually gray and gloomy at this time of the year, has been nothing short of G-O-R-G-E-O-U-S, and everyone i meet seems in an infectiously happy mood. I start knowing my way around SF a little better each year, staying with a friend in the Mission and Bernal Heights districts, and their abundance of great little cafés and restaurants…. and… bums, which seem to be a great SF specialty.

Monday morning i was rather startled when a homeless-looking guy started talking to me in the cheap coffee place where i was getting breakfast. I never refuse conversation no matter how busy, so while i was flagging AGU sessions in the meeting book, i was distractedly answering his questions. He asked if i was “one of them dot com guys”, but when i said i was a climate scientist, his eyes started to twinkle and he started to talk about tree-rings for the next 15 minutes.

That’s why i do this job : even destitute people care about our climate more than their own (considerable) problems.

Anyway, not any encounter here is that ghetto - far from it. In fact, the sociology of this meeting is deeply fascinating. Being somewhat plugged in with the Lamont mafia , it lead me to a beer with the CalTech mafia , joined by prominent members of the the Harvard mafia and the WHOI mafia.

The field is quite small, everyone is of rather pleasant (and sometimes, downright excellent) company, and schmoozing is an integral part of science. It would be silly to deny it, so let’s enjoy it : when the beer pitchers circulate that fast around a table of climate scientists, ideas flow just as fast as the bubbles.

It is always very funny to see who is going to lunch with whom, and just as importantly , who is NOT going to lunch with so-and-so, because they are big shots who irked one another 55 years ago and no one will step down from their distant pedestals. It’s quite amusing and i imagine it is like this in every field. The one thing that may be increasingly characteristic of AGU is the amount of press people - and politically-charged talks, like that given by Presidential Science Advisor John Marburger III.

That one was sure to disappoint : there is nothing more saddening than to see a good brain develop intricate excuses for the irrational behavior of his hierarchical superiors. Marburger is obviously a very intelligent man, and his command of the many facets of the climate challenge seems as complete as can judge it. Nevertheless, he spent his address distilling some political speech to tame the science, before explicitly refusing to address some pointed political questions when they got a little too hard to handle.

Lame.

Far from the usual mafias, and at the risk of displeasing certain mainstream scientists, i went for lunch with Steve McIntyre yesterday. After a past few weeks of throwing hand grenades at each other from behind electronic sandbags (i.e. blogs), it was very pleasant to talk eye-to-eye and shoot the breeze.

I can’t help but thinking that a lot of the bitterness in our sour climate debates would be eased out with a proper lunch… But maybe i am being too French again.

All right, time to go !

Sorry if i’ve been behind comments lately : found that this morning to my surprise, that there were 8 unmoderated, week-old comments, and i apologize for the delay in posting. Blogger sucks (if you needed a reminder ;-).

Blogspot, you suck.

hi all, sorry for lagging behind in the responses to comments.
i had a much-needed reflective Thanksgiving break. And tried to do some actual work, instead of just yacking.
And then when i opened the Pandora box again, there were plenty of comments from my good friend Anonymous, from that guy Anonymous, and also from that really obnoxious goon called Anonymous.

So i started composing a structured reply to be posted as comment, and then blogspot complained that i was using too much HTML code, so that’s it : blogspot, you officially suck. I can’t reply to comments inline, it’s a nightmare to moderate them, they look like crap compared to any WordPress blog, i can’t require guests to leave an email address so that snipers stay home, and we can’t even geek out in LaTeX.

So blogspot, you can kiss my French ass goodbye. In just a few days this blog will move to a new address, because enough is enough.

In the meanwhile here are a few answers…

Cheers !
Julien

Francois O :

i am sorry you took those words personally… if you re-read my response to your comment, you will see a “their”, not a “your” : a reflection of my limited experience in reading/talking to certain obscurantists. I never implied you were one.
I did make the mistake of imparting you some political motives. It is an error, because i don’t know them, as you point out. I was just a little annoyed that we climate scientists are always accused of political bias by virtue of being academics, (which in my experience is largely liberal). Can we stop this, everyone ?

Call me naive, but I do believe than my political opinion do not obscure and distort my scientific judgement, or at least much less than MIT’s Richard Lindzen’s when he states “AGW can’t be a real threat because that would require us to live like cavemen” (video interview for an exhibit at La Cité des Sciences et de l’Industrie). Yet, oddly enough, i haven’t seen a good skeptic get on his back. But perhaps there is one - does anyone know ?

Yes, i am ready to face the consequences of a world economy based mostly on non-fossil resources . Does it mean i will suspend my scientific training to blindly accept any alarmism ? No, and i am offended when such collusion is made.

But you’re right, François, i shouldn’t be guilty of the same sin of collusion.

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Anonymous said…

Oh please, have you read realclimate lately? The sneer factor over there is off the charts, and they religiously excise nearly all dissenting comments.

As for cheap shots, those same “prominent climate scientists” routinely use the term septic or denialist (with its deliberate holocaust denialist association) to describe anyone who questions their authority. Some of us doing the questioning are very well-qualified indeed. Needless to say, such an attitude from supposedly professional scientists has very much hardened opinions against them.

As i said before, i believe the denialist term is fully justified when applied to people who bury their head in the ground against an overwhelming amount of scientific evidence. That said, RC may well censor too harshly.

Incidentally, I tend to censor posts by “anonymous” , because it’s too darn easy to be a sniper. But yours were interesting comments, so i left them in.

In particular, it reminds me of watching my own sneer factor. The problem is that blogs in general are also meant to be somewhat entertaining to keep the audience on their toes, so there is a tendency to joke about “the other side” in ways unimaginable in a science paper. As another ‘anonymous’ said, “how many people read blogs that aren’t amusing?”

More accessible and less dry than science prose, but also not as professional. You can’t have everything….

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non-anon said…

you should be fighting hardest against the realclimate scientists. These guys are (almost to a man/woman) pushing a negative growth, nature over humanity political agenda, and they are using AGW alarmism to do so. They truck no criticism, nor any questioning of their authority, just like the catholic church of yore.

I think the most useful fight consists in showing a “third way” where a most balanced view is advocated and practiced. I never pretended to be the epitome of objectivity, but i can only hope that after a long enough observational period, you and other readers will place me somewhere in between extremes.

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Anonymous said…

Steve McIntyre is pretty tedious. He’s been picked apart numerous times and he keeps coming.

Like a zombie.

It’s pretty amazing that he has been able to take a single peer-reviewed study and parlay it into so much attention.

How McIntyre Got Famous

Skeptics Get a Journal

But that’s what you get from the internets…..

Hey now ! This is not a blog to vent cheap shots at either side.

I deeply respect Steve McIntyre’s talent for digging through datasets, his mutinous perseverance, his incredible diligence at addressing topical climate issues (one wonders when he sleeps !), and as a dude who likes writing (can you tell ?), i respect his writing style very much. Also, he really impressed me by going to collect some date out of his own free-time and funds - that is light-years beyond what the armchair skeptic would do, and shows a genuine thirst for answering the questions, which is very commendable.

A quick browse through his posts will convince you that he’s contributed much more to climatology than a GRL article (which, as Huybers showed, has its own problems).

So while it is no measure of scientific quality than to be highly held by the editorial board of the WSJ (talk about bias !!!!) and Sen Joe Barton, i suspect the situation would be very different if “mainstream climatology” (to which i now belong…) had given him the attention he deserves, instead of constantly dismissing his comments.

Of course, it would help if he chose the “normal” avenues of science, with a slightly less offensive tone, but that’s a style i personally enjoy. It’s not for the weak at heart… neither is this blog, obviously

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Anonymous said…

What is going to happen if the earth cools as CO2 continues to rise? Science needs a champion, now.

Oh, brave Anonymous, i see a role for a luminary like you in our fast warming world !

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Wow, TCO, what prolific commenting !

I really appreciate your comments as you seem to know the issues quite well, but again, this is not a McIntyre-bashing blog. I think the best test of whether he’s right and wrong, and on which topics, will come from the harsh light of confrontation (with gloves on). But this requires paleoclimatologists to engage in a fair debate with him - one whose rules are not dictacted by ClimateAudit , RealClimate, or yours truly of course.

I really want to invite him to speak at Georgia Tech and see if he has anything of substance to say, and can convey it in a clear manner. This might pave the way for a more fruitful discussion. I’ll keep you posted…

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Gianni, as i have said, data availability is absolutely fundamental to the progress of this field. I never asked for a “pass”, just a little more understanding, because i think few fields feature datasets that require so much personal time, effort and contact with the elements. I may be wrong. Anyone has examples ?

Now this :

Nobody would care about the antics of paleoclimatologist if it were not for the fact that many of them want to change society back into some sort of hunter gather community. Sorry, forget about the hunter bit, we probably would not be allowed to eat the animals anyway!

I am sorry to say, this is plain and aggressive ignorance. First, most paleoclimatologists stay quite clear of advocating policy choices. Please show me a study that would demonstrate the opposite. Second, i do believe there is a middle ground between industrialism gone wrong and pre-history. It’s called progress. It’s not a middle-ground, actually, it’s a different dimension altogether. You could try reading this for a more informed perspective.

Thirdly, as far a vegetarianism is concerned, you should probably read what an obscure physicist called Albert E. had to say about it…

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Anonymous said.

El Niño

I apologise for setting such a bad example to ‘the youth’ by posting anonymously, but of course this does not in any way effect what I said, which was that the integrity of an argument can be evaluated by the way in which it is formulated and expressed. Only sound, fallacy free, arguments are likely to persuade AGW sceptics to join the ranks of the orthodox. And sceptics do have to be persuaded, they are unlikely to be coerced by name calling, abuse, or peer pressure.

True. Yet, if i am risking by public persona in the arena, i think you should show the same elementary courage.

In your response, you have impugned my courage, suggested that I am a corrupter of the young and managed to work in the ‘flat earther’ insult too. Then, as if one fallacy (ad hominem attack) was not enough, you cite ‘the expertise of ~450 authors’ of the IPCC, a blatant appeal to authority. Unfortunately you have not addressed the substance of my comment, which is a pity because I would have been interested to hear your views.

Well, yeah, i was poking a little hard because i do despise snipers. I have re-read your comment and still do not find matter there to address - except that i am arrogant. Are you asking for explanations ? Do you want to see a copy of my French passport No, seriously, if you want me to address something in particular, please rephrase it and i will do my best to address it. As it stands I have not gotten your point.

You say :
In the real world, outside academia, it is frequently necessary to act on matters of importance without having expert knowledge. And knowledge does not confer infallibility on anyone; not even climate scientists.

In my opinion, an “expert” is only as good as their ability to convey their knowledge. So let me re-try again to convey my view : while climate orthodoxy does sometimes does a poor job of recognizing holes in their own arguments, it is a VERY different thing from the pure disinformation campaign run by some skeptics.

No, we don’t know everything about the Earth’s climate. And we should certainly be more humble about it. But we know enough to say that physical and biological systems on Earth are undergoing enormous changes , that these changes are mostly caused by human activities ; at current per-capita emission rates, future anthropogenic global warming is thus a real and serious threat, and a wide spectrum of climate and economical models concur to show if we do nothing the consequences will likely be disastrous for our way of life and our children’s. That’s my appeal to ‘authority’.

One cannot always act with ‘expert’ and complete knowledge, but wouldn’t you agree that good decision-makers do refer to experts before taking action ? Because the issue is so huge, there are many experts worldwide - and the fact that they can reach a consensus is pretty powerful thing, methinks.

One can search for balance on political issues all their life - that is all fine. But this is science, and their comes point where the frenetic quest for ‘an informed opinion’ turns from healthy skepticism to blind denial. We may not agree on the location of that boundary, so i would be curious to hear where you place it.

What we, as a global community, choose to do as a response to AGW is (or should be !) a matter of debate : and that’s where economics and politics enter. But the basic tenets of the science are hard to dispute unless one wants to step pretty far out of the realm of logic. Is this a point you want to discuss ?

Perhaps i was excessive in saying that ‘most’ of the Opposition is made of obscurantists. I would be thrilled to see proof that they are made of rational, healthy skeptics who simply have not been put in presence of the overwhelming mound of evidence. But i am reminded every day of how many obscurantists there are in the media, and i don’t think i could ever fight them hard enough - there is indeed too much at stake.
Perhaps i should change strategy, though, and your comment will encourage me to think about it.

What would it take to convince YOU, dear Anonymous ?

PS : i did not get the Eli Rabbett joke . Call me silly.

An open letter to Craig Loehle

Dear Craig,
I wanted to explain the position of wariness i have publicly taken on a potential collaboration with you.

First, i should have thanked you for offering it, because that implies that you believe i could contribute something useful. Quite a few people know vastly more about this subject - but it could also true that they might not be so open to collaboration outside of the tried “teams”. Hence my inexperience comes as both a blessing and a curse, but i am honored that you would even consider a collaboration with me - especially after some rather unsparing critiques. This alone is reason enough to respect you.

I have been prudent, however, to get involved in collaboration, as i wanted to be sure that you are after the answer to the old question “Was the Medieval Warm Period (MWP) a global signal and was it warmer than now ?” - and not just another dissenting publication to give fuel to the AGW-denying side, throwing away the standards of scientific publications that you seem to have upheld during much of your career (if i am to judge from a quick Web Of Science search, and browsing through a few papers).

You seem like a very creative scientist and i would never mean to downplay the contributions you have made to applied mathematics. The issue is, as far as i could judge from that one Energy & Environment article, you did not seem genuine and serious about answering the aforementioned question. This, some flamboyant prose notwithstanding, is the essence of my review.

Also, you referred in the 2007 article to a discussion of the MWP in “Loehle (2006)”, whereas upon closer examination, the paper lists only 2 references of yours : one in 2004, one in 2005….

- Loehle, C., (2004). Using historical climate data to evaluate climate trends: issues of statistical inference. Energy & Environment, 5, pp. 1-10.

- Loehle, C., (2005). Estimating climatic timeseries from multi-site data afflicted with dating error. Mathematical Geology, 37, pp. 127-140.

I just read the latter article and found it extremely interesting. I fully agree that the field of paleoclimatology has failed to taken dating uncertainties into explicit account (p137, top line). This is something i have recently started to work on, and yours is exactly the kind of contribution that could change this. The last paragraph, however, left me quite dumbfounded :

it is not sufficient to simply average historical data to produce a global or hemispheric timeseries, because dating error afflicts virtually all extant pre-instrumental reconstructions. There are two options available for obtaining statistically valid global or hemispheric timeseries. If better dating methods can be developed to reduce dating errors in proxy records, then simple averaging of series is valid. Given the many sources of dating error, this is a challenge. If, on the other hand, multiple series can be estimated, the estimation methods developed in this paper can be applied to identify trends and cycles in the historical record, even with dating errors.

(p 139)

So, if “it is not sufficient to simply average historical data to produce a global or hemispheric timeseries”, why did you do so in the E&E article ? And why didn’t you apply the two-stage nonlinear estimation technique you describe in the Mathematical Geology article, since it was so readily available to you ?

Have i been unfair to you while overly indulgent with my colleagues ? I have been accused at ClimateAudit.org and on this blog of not taking a “hard look in the mirror” - a fair criticism i mulled over this during the Thanksgiving break. As i’ve stated elsewhere, my criteria as a reviewer have been :

1) Is the result or approach original ? Does it recognize prior scholarly work on the topic ?
2) is the methodology described with enough detail ?
3) are all important choices substantiated by reference or discussion ?
4) are the uncertainties appropriately discussed ?
5) are the conclusions warranted by the analysis ?

(these would undergo minor adjustments according to the field of study, e.g. paleoclimate vs. recent climate vs. climate modeling. They are by no means universal, and i welcome suggestions from other adepts of peer-review to refine or correct them.)

Be that as it may ; in the case of you paper, i would answer by :

1) yes

2) not for me
3) somewhat (yes for excluding tree-rings, no for why certain other problematic proxies were retained)
4) no
5) no

So that would lead me to ask for major revisions, or plainly reject the manuscript if i felt that the author were not of good faith. As i said in the review, a few other minor flaws hinted to the latter.

How would these criteria apply to other published reconstructions ? Let’s take the canonical “Team” global reconstructions (Mann, Bradley and Hughes, [98/99] ; Esper et al. [2002] ; Moberg [2005], Hegerl et al 2007), that i have read in sufficient detail. I state here, that while all of them have their own limitations, the same criteria i applied to your article would lead me to accept them as valid contributions to paleoclimatology - but obviously not as the Climate Gospel. In particular, much remains to be done to address uncertainties in time and temperature (X and Y, so to speak) and estimate error bars in a manner that truthfully reflects the uncertainty in the reconstructed temperatures. It is a problem in our field as a whole, one where i can only hope to make some advances myself. I never demanded you to miraculously solve all the problems of paleoclimatology in one fell-swoop ; i merely demanded proof that the basic homework had been done. Since your paper gave such a displeasing impression of the opposite, i labeled it as “pseudo-scientific gibberish”. This seemed to get quite a few people angry at ClimateAudit (although this is not a very hard thing to do ;-), so I re-iterate my definition :

Is pseudo-scientific any text or speech that wears the attributes of science while lacking the necessary rigor in the essential fulcrums of its reasoning.


and stand by the claim that the adjective applies to the E&E manuscript in its present form. I concede that “gibberish” was a somewhat excessive substantive, and i apologize for this unnecessary strike.

So, after this clarification, what do we do ? If you are ready to meet and address these issues in good faith, i would be more than happy to help in whichever little way that i can. I do believe that much is to be gained from a insightful application of mathematics to climate proxies, and would be thrilled to take part in it if our objectives are common. If you are still interested, you know where to find me.

Of course, you are perfectly free to ignore this call - after all this is only a blog and there are more important things in life.

Sincerely,
Julien Emile-Geay

The Loehle Reconstruction

So this is my Sunday-night review, hopefully a more peaceful one than my Friday outburst on Climate Audit. I have re-read the paper and don’t have many more nice things to say about it… But hopefully i have weeded out the superfluous - including the “aggravated tone” . There might still be some irony left : apologies in advance.
I have refrained from reading CA comments that followed by friday-evening post (221), to stay on point. Comments to the answers to the comments to the questions will come in due time (i have a busy week coming up, and have unchained quite a firestorm that i cannot tackle tonight…).

Before we start, however, I have a few disclaimers to make :

• I am conducting this review alone. This is unrequested work, i am only doing it for the defense of my own scientific conviction and to share it with other readers, some of which have little background on the subject. Needless to say, the form would be vastly different if this were a review carried out for a scientific journal. However, my angle on it is : does Loehle’s reconstruction, meet the basic criteria that i would apply to a review, were i asked to be a referee ? Anyone is free to disagree - and i am looking forward to insightful comments from statisticians.

• Since the issue has started to appear on this CA thread, let me be perfectly clear. I am not here to defend previous work : the sole focus of this review is Loehle’s article. I am a newcormer to this game, having entered the wonderfully charged world of paleoclimate reconstructions less than a year ago. As such, i do not pretend to have inoxydizable expertise on all recontrusctions to date, much less on all of ClimateAudit’s blogposts. Hence, please do not ask me to justify so-and-so’s methods. Loehle comes as a challenger in this game, and i believe it is the job of the underdog to do at least as well as the Establishment he criticizes. I will accept no excuse of the type :”this had not be done in the usual reconstruction” if they are demonstratedly doable in the case of this simple method (cf error bars). McIntyre is well-founded when he says that much of my criticisms would apply to some previous work, none of which have i ever pretended to defend.

• I am not emphatically not here on behalf of RealClimate, the IPCC, GaTech and certainly not here to defend Dr Mann. I am entitled to the independence of my views and refer to none but my own education, judgment, and bibliography. Dr Mann, on the other hand, is entitled to the defense of his own work, has done so with relentless (and arguably, successful) effort over the past 9 years, and is an equally independent scientist who can fend for himself. My own opinion on the MBH99 reconstruction ? I wouldn’t bet the family farm that “1998 was the warmest year in at least a millennium”, but i agree with the NAS panel when they find that , “with a high level of confidence [...] Global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries”. Ditto that is it is plausible that “The Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium”.

  Mann’s publication record speaks for itself, he and collaborators like Scott Rutherford have undertaken very extensive re-workings of the MBH98/99 algorithm, albeit not necessarily gracefully - in CA’s eyes. I wholeheartedly agree that climate science is lagging behind other fields in terms of providing open access to data and methods, and Steve McIntyre’s efforts are much needed in improving these standards. Nonetheless, i find CA-dwellers a little antiquated in their constant re-hashing of MBH98 criticisms. They would be well inspired to direct them at his most recent work if they so wish, rather than beating horses dead in 1998 or 1999. While it is true that MBH98 is not the panacea of climate reconstructions, it would be reductionist to corner all of “Team” into one article and ignore almost a decade of subsequent work. Since CA readers get understandably upset when i lump them together with climate obscurantists, they should lend a sympathetic hear to the statement that not every climate scientist is guilty of pensée unique.

---

Review of Loehle (2007).

The article comes from Craig Loehle (a PhD in Mathematical Ecology with a rather freshly-discovered interest in climate research) , and published in the infamous “Energy & Environment“, a peer-reviewed journal that recently emerged as the number one printing device for climate obscurantism. Indeed, said ‘peers’ do not seem to know much about climate. Be that as it may : let’s go beyond appearances and give the paper an honest read : Loehle could be a revolutionary mind, whose deep mathematical insight will cure many of the ailments that have henceforth plagued the efforts of many a climate scientist - who, owing to CA, are allegedly ignorant in statistics.

We start by an extensive introduction that argues for the inability of tree-rings to record any temperature signal on the period of interest, and is decently informed. While it would be excessive to throw out just ANY tree-ring series (though they had issues with strip-bark trees, i don’t believe the NAS panel recommended the incineration of the entire dendroclimatological literature), the point is well taken : in light of the many factors that influence tree-ring growth over long periods, it is certainly a valid “What if ?” experiment to produce a reconstruction free of such data. Since the author acknowledges that it is not the first (Moberg [2005] and Viau et al [2006] have already done similar things) , we are eagerly awaiting what original statistical techniques will be presented here if the author is to arrive at a substantially different conclusion.

Eyebrows start rising when the only references given to support the existence of a “Medieval Warm Period” (MWP) are from the author himself (Loehle 2006), and Soon and Baliunas (2003), which has been thoroughly debunked by RealClimate colleagues (see Myth #2). For those not so versed in blog wars, The MWP is a favorite of global-warming denialists, because if you coax the data into showing a warm enough early millennium, you can negate all of the IPCC’s work : it’s super duper cool.
Unfortunately, there is ample evidence that the so-called Medieval Warm Period was far from global : see for instance the NAS report (North et al, 2006, chapter 11 and references therein). There is, however, great interest in understanding why it was warm in Europe or dry in the US South West and central America, and seemingly cool in the eastern tropical Pacific (cf Graham, 2006), so let’s read on.

METHODS : The section is startlingly short. 18 proxy timeseries are selected on the grounds that : a) they are available for 2000 years b) they are not tree-rings. A decent case is made that one should not worry too much about dating uncertainties. Fair enough. What next ? Data are smoothed, standardized, and… averaged. Period.

I had to read the article 3 times (re-downlading it just in case i had gotten a faulty version the first time) to convince myself that i wasn’t dreaming. All subsequent figures show the arithmetic mean of 17 or 18 series, as if they all recorded local temperature with the same accuracy, and were representative of the same geographical area.

Proxy temperature relationship

Since the article’s title mentions a “global temperature reconstruction”, one would expect two fundamental aspects to be discussed . 1) these are reliable temperature proxies ; 2) they are representative of a global average. In that light, i expected the merits of said proxies as paleothermometers to be at least brushed upon. There are only 18 of them (unlike most paleoproxy studies, which can compile >200 ), so it wouldn’t break the author’s back to at least READ the papers he is citing, dig up the error estimate, and put this all into a pretty table. It’s not so clear he does *read*, however, otherwise he wouldn’t have retrieved a “Borehole 1 temperature” from Dahl-Jensen et al. [1998], just a borehole temperature inversion.

This is a very different situation from usual multiproxy studies which use sophisticated methods to ensure that a proxy’s weight in the final result reflects its ability to record some variance in the temperature field (whether local or not). While there is merit in exploring a bare bones approach (arithmetic mean), it then becomes indispensable to demonstrate that each proxy is : a) a temperature proxy (not a salinity one…). b) a good one at that.

At first glance, a) is dubious for the Holmgren and Keigwin timeseries (that’s at first glance… i need to dig more), and b) can usually be assessed from the authors’ error analysis. If it is not, then the author should conduct his own, or drop the use of such proxy.
Once again, such care would not be required when a climate-field-reconstruction or “composite-plus-scale” approach is employed, as the proxy’s ability to record temperature is implicit in the calibration therein. Since the author effectively treats the proxies are perfect thermometers (which is conceptually acceptable as long as it is explicitly justified), the lack of this discussion is unforgivable, and in my book, constitutes grounds for rejection any day of the week.

Error propagation analysis

This part is usually immensely complicated in the case of non-linear estimators, but it should be a piece of cake here. Since the proxies are so concisely described (i agree that a map would have been nice - apparently it didn’t take S. McIntyre very long to make one), it comes as no surprise that the final result is utterly devoid of error bars.
Instead, the author chooses a jacknife analysis, which in my view only speaks to the relative importance of each proxy in the final results. Imagine all proxies had a standard error of 2.5 degrees with the actual temperature : this analysis would say nothing about the accuracy of the mean.

Let’s be more constructive than in my original CA post : there are several possible approaches. For instance, one could assemble a vector of proxy errors, and assume the temperature proxies are iid and Gaussian, which is quite reasonable. It would not take a PhD in mathematics to prove that the arithmetic mean is also a Gaussian random variable with a standard deviation that is the L2-norm of the sigma vector (divided by the number of series). This is rather simple-minded, but since the approach is deliberately simple, it would be consistent with this framework. There maybe more elaborate ways, as discussed by Hu McCullough here.

In any case, it is unacceptable to make the quantitative claim that the data ”would indeed seem to show the MWP to be warmer than the late 20th century” , “by about 0.3 degrees. This number is worthless without an error bar, or at least an insightful discussion of uncertainty.
Rejection again, sunday or friday.

Reconstruction skill.

Again, impressive concision ! Where are the CE, RE, and most importantly R-squared statistics that are so dear to ClimateAuditers when used by the Team ? How are we supposed to guess whether the reconstruction has any skill ? (skill, by the way, is a ubiquitous term in the numerical weather and climate forecasting literature. It is intuitive enough, but if statisticians need a more statistical term, i can try and dig one up over the next few days). In his original response, Loehle argues that these statistics are irrelevant because he does not have a model. This is false, as pointed out by bender, and myself. Despite claims of using a “simple mean”, the author’s approach is effectively a multivariate regression. Indeed, each of the proxies was calibrated against temperature using such regression methods, usually linear, but sometimes non-linear (Mg/Ca ratios depend exponentially on seawater temperature, for instance). So by doing even a simple average, the author is effectively using a statistical model, and is therefore not exempt from the verification exercise.

(incidentally, i regret that bender seems to believe i have been plagiarizing his ideas. I was responding to earlier comments when he posted his and did not see them until after i had submitted mine - an unfortunate consequence of the high traffic at CA… This convergence does, however, suggest we have more in common than what superficial disputes would suggest, so perhaps one day we’ll have real dialogue)

Minor comments :

- I could not find a reference for “simple mean” (p1053). It may be a novel contribution to the mathematical literature - which had heretofore used “arithmetic mean”. I only point this out since CA statisticians seem always eager to correct climatologists on their improper use of statistical terminology. While i am genuinely eager to be educated in statistics, i wish the same standards applied to everyone.

- I believe it is the first time i read ‘I believe’ in a scientific paper (it’s different in politics), and it is there 3 times in the discussion. Hmmmmm…

- R. Villabala does not appear to have any publications on the Medieval Warm Period. Ricardo Villalba, other other hand, does. (the error is present in the text and reference list). This reinforces the feeling that the basic homework really hasn’t been done.

In summary, this article is a poorly-described compilation of proxy data, with a conciseness in methodology that borders on farce. In the present form , it is unacceptable in any scientific journal that i am aware of. Though the approach is conceptually useful, it is not novel : the author himself acknowledges that Moberg (2005) and Viau (2006) have left out tree-rings from some parts of their reconstruction before. So what is new here ? It can only be the methodology. We have shown that its elliptic nature is naive at best, misleading at worse. Even with all the good will in the world, it is hard to grant the author the benefit of the doubt, given how loosely he handles his references and prose : this simply is not credible work. The author’s argument that his “strategy in writing this was to make it as short as possible to avoid complications during review” is distinctly unconvincing. Why not, then, bypass the whole ‘methods’ section, and simply give us a curve without any explanation ? Brevity is the soul of wit, yes - but when crucial information is missing, this “science” has an odd scent of disinformation.

I am glad to see that a healthy debate has now engaged on CA and that Steve McIntyre has undertaken a serious audit of this study (e.g. here and here). Already, some of my question regarding spatial sampling have been admirably addressed, and though it should have been the author’s job to do this before submission, the only thing that matters here is that the question be answered somehow.

I hope this debate will bring Craig Loehle to produce a scientifically-acceptable reconstruction - one that meets our basic field’s criteria for publication. He would otherwise condemn himself to sub-standard journals like Energy & Environment, ensuring that they are invisible to climate scientists - for good reason.

Let’s audit Climate Audit !

Hi kids ! It’s been an interesting week-end …

On thursday, Nov 15th, i was notified by the Chair of my department, Dr Judith Curry, that a new reconstruction of global temperature had been published (Loehle,2007), and that a thread on it had been started at ClimateAudit.org.

For those not involved in blog wars, the latter is an interesting blog animated by Steve McIntyre, a climate skeptic with merciless talent for tearing apart a dataset. The word on the street is (some readers may want to correct me here) that McIntyre created this blog after getting frustrated that his comments were never addressed, or even posted, on RealClimate.org .

I am a regular reader of RealClimate.org which gathers distinguished scientists of the likes of David Archer, Stefan Rahmstorf, Ray Pierrehumbert, Gavin Schmidt and Michael Mann. These people are personally ersponsible for some of the msot exciting work in climatology, their blog has won a few awards and it is increasingly taken as authority by a number of newspapers, including my own “Le Monde” from Frogland. Blog posts on RealClimate are often entertaining, always informative, but it arguably leaves little room for heterodox climate views and it sometimes leaves the strange aftertaste that its authors are defending and selling their own research, while not explicitly acknowledging this partisanship. In particular, Michael Mann is the lead author behind the illustrious Hockey Stick graph, which is by any means a very controversial piece of research, and RealClimate.org (RC) has proven somewhat closed to discussion on the topic - at least coming from McIntyre’s clique. Though i have not personally experienced censorship on RC, i have heard many accounts thereof. It is perfectly sensible to block global-warming-denialist trolls from spewing out insults on the forum, but not intelligent laymen who ask inconvenient questions. So quite a few people (climate scientists included) have gotten frustrated with RC as well. (today’s post about my former ministre de l’Education and his apprentice Courtillot is an absolute gem, however. Highly recommended).

On the other side of the aisle, you have Steve McIntyre and his now growing number of readers on ClimateAudit.org (CA). McIntyre apparently jumped into the climate game because of some (legitimate) concerns he had with the Hockey Stick graph, and has since turned his attention to just about every piece of data that is being used in the media in climate discussions. The man seems a rather interesting fellow , with a solid math background, a painstaking attention to detail, and a devastating verve that makes his blogposts rather entertaining to read. More recently, he has deeply impressed me by undertaking some tree-ring research out of his own free time and on his own funds : there are a lot of armchair skeptics out there, but this man is doing serious work.

The strength of CA has been its openness to comments from all sides, which fostered the growth of a crowd of hard-to-please data analysts, crafting ever-more-well-posed questions and challenges to the climate science community. It is, in my view, a much needed addition to the climate debate, with expertise from various fields of mathematics, statistics and data analysis. As a scientist i wish they were taken more seriously by our community. It is natural for every society to get a little complacent and it runs the risk of resting on its laurels, unless challenged by an Opposition.

The main problem is that until recently, the Opposition was mostly represented by the despicable breed of “climate obscurantists” who have been polluting the blogosphere with a pure disinformation campaign, motivating their disparaging comments on all states of climate science by their own unwillingness to change anything about their fossil-fueled existence. These comments are always easily debunkable because they are not based on any scientific knowledge or reasoning. I would hate to be guilty of referring you to such pieces of junk, but if you want a taste , Texas Rainmaker, America’s Future or the editorials of the Wall Street Journal are quite good examples - there are unfortunately many, many more.

Hence, for a climate obscurantist, if you are with the IPCC, you are for the “climate terrorists”, no lie is above you and no punch is too low. Fortunately, CA started on very different premises. While i know little about his underlying motives, McIntyre is a very sharp fellow whose pointed questions help create a healthy debate in the field. If the IPCC consensus is as indestructible as we claim, then it must be able to weather these storms. Better still, it could be a little shaken by said storms and would emerge stronger and more legitimate.

Further, McIntyre is joined in his investigation by a vocal group of readers and commentators, some of which are quite on-point. The CA crowd is a tough one for sure : the educated skeptics in there, while decently equipped in verbal courtesy, are entirely exempt of magnanimity, and don’t let you get away with much. It’s a bit like the All Blacks rugby pack. That’s all right : i have no problem with tough players. Unfortunately, the openness and the global-warming-trashing bent of CA means that some of its participants are of the “obscurantist” breed, and are more vocal than warranted by their science credentials.

One also finds a distinct self-congratulatory tone in there, and when McIntyre makes a sneering cheap shot at a prominent climate scientist, the joke is greeted with loud cheers and pats in the back that are more reminiscent of a low-grade frat house than a respectable scientific society. This is corny at best, and most often downright tiring. Hence the somewhat playful urge of yours truly to go challenge the pack on its own turf at some opportune moment….

The opportunity materialized last thursday with the publication of a new indepdendent temperature reconstruction, one that shows a very warm “Medieval Warm Period” (aka “Medieval Climate Anomaly” because it was almost certainly not warm everywhere - more on this later), and thus poses a particular challenge to CA. Are they going to scrutinize it as ruthlessly and righteously as reconstructions that support the idea that the twentieth century warming is anomalous in the context of the past millennium ? Or are they going to congratulate the author for his “unbiased” work, pat each other in the back, and go on insulting Mann, Hansen and tutti quanti ? Does CA stand for Climate Audit or Curmudgeon Association ? Is the “skeptic” crowd even skeptical of its own children or is it a privilege reserved to mainstream climatologists ?

So on friday yours truly posted a review of it on CA. If you are curious enough to read some of comments in there (477 at the time of writing), you will find that my little post generated quite a storm.

I spent most of friday answering some of the rebuttals and other comments, and i have to say it was quite enthralling. I evidently pushed some buttons there, and undeniably some of them were quite sensitive spots. The best compliment was by Pat Keating :

You have a nice turn of phrase, and would love to read more of your critiques, preferably in the context of the AGW acolytes’ work<

So apparently i am good enough to join the Dark Side. Exciting…

Later, McIntyre started his audit and so far i am pleased to see he is not giving Loehle a free ride. This is only the beginning.

I acknowledge, however, that i wrote my CA posts in the heat of the battle, which is never a good thing. As a Kokikai Aikido practitioner, i should know better. Whenever i am given an article to review, i usually make sure to do it over a period of a few days, so that the second (or third ) reading might provide a different light and help me be more objective - particularly if i thought the article unacceptable at first read. I violated this rule on friday because i was too eager to go make a splash on CA - to make a statement that they were also being watched and that some people will prove just as picky about the Opposition’s statements than they are about the Establishment. That was quite shallow, ego-driven, and i took somewhat of a sadistic pleasure in lacerating that article - while i could be more constructive.

As my neighbor Dr Martin Luther King Jr used to say : “An eye for an eye leaves everyone blind”. As it turns out, my former NY roommate was in town this week-end and I had a fantastic time : full of laughter, Venezualian aged dark rum, frisbee-tossing in Piedmont park, rosemary pork loin roast, neighbors dropping by the dinner table all night, and late night jam sessions till we fell asleep on the instruments. Today the Sun was so intense that we could suntan on my rooftop with a good cup of tea, and i just got out of a very grounding yoga session.

So let’s chill out for a bit : true, Loehle’s article (in its present form) is a poorly-written piece of pseudo-scientific gibberish - but now that i have the watchdogs’ attention there’s no need to be barking anymore. It would be a poor tribute to a gorgeous week-end than to remain sulky.

In the following post, i will thus summarize the article in question, present the issues i have with it and respond to as many CA comments as i can before falling asleep. We’ll see where it leads…