Adoration of the Lamb


Continuing vaguely along the theme of use and abuse of IPCC 1990 fig 7.1(c), its worth noting explicitly the worship of Hubert Lamb by some of the denialists. I don't think I need to repeat what is said there, but make sure you read the comments, especially those from Willard, and me of course.

One interesting example of this, which illustrates the same problems, is Premonitions of the Fall (in temperature) at WUWT by David Archibald. Its a very silly post, but it adopts the usual policy of taking all of Lamb's stuff uncritically, whilst ignoring recent work, in order to push the authors own views.

For a saner discussion that involves Lamb's work Hughes and Diaz 1994, which recently fell my way, is a good example. It treats Lamb with respect, which he deserves, but not as gospel, which he also deserves.

I'm pleased to find a linkage back to the Goode Olde Dayes of sci.env: ah, those were the days. I kept it in the context of the "global cooling" meme, but it applies to fig 7.1.c too. mt can write well:

It is important to note exactly who made those predictions, (or more properly, who expressed those worries) about an imminent ice age, and who is now predicting rapid global warming. By and large these are not the same people. The first group was essentially the observational paleoclimatologists. Bryson still claims that "the proper tool of the climatologist is the shovel". The compendium by Lamb which Tom Moore takes as his primary reference was essentially the pinnacle of achievement in that field.

With all due respect (I mean this quite seriously - the erudition and breadth of knowledge of these people, Lamb in particular - is enormously impressive) to that group, their grasp of mathematics and statistics was weak, and of physics weaker still.

For instance, Lamb's prediction in particular of imminent and rapid cooling was based on, essentially, a crude Fourier analysis (best fits of sinusoidal curves to his record). Since one of the dominant features was a rapid rise over the last century, the *presumption* of a cyclical nature of the record forced a prediction of a rapid cooling *precisely because there had been a recent rapid warming*. And although the niceties of periodograms had all been worked out by that time, Lamb seemed blissfully ignorant of the need to take particular care when fitting sinusoids to a record with significant information at its termination.

In the 1970s, a separate discipline of physical climatology was just emerging from an infancy at the peripheries of mathematics and astrophysics.


* Early version of temperature history - me, from 2005.
* GWPF, 2015

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The adoration of Lamb is unsurprisingly partial, and the early '70s predictions of cooling didn't last very long. From Michael Sanderson's 2002 book, The history of the University of East Anglia, Norwich, p. 285, discusses Lamb starting CRU in 1972:

"Professor Lamb came to Norwich as "the ice man", attracting much attention for his prophesy of world cooling and a future ice age within 10,000 years. Within a few years in Norwich, in which the heat wave of 1975–76 had intervened, he had switched to warning of global warming with dire predictions of forest and crop belts being shifted, melting ice caps and drowned cities. A holocaust within a century was an even more exciting prospect than an ice age in ten millennia and it helped to shape contemporary attitudes to global warming."

[That is impressively well-read of you. Thanks for the quote -W]

There seems to be some confusion about what Lamb believed concerning global cooling. Michael Tobis' text above suggests he was thinking about imminent cooling on a multi-decadal or centennial scale but, from the little I've read, I thought his cooling concern was related to glacial cycles and the paleoclimate observations that we are currently in a warm phase which, naively, appeared likely to end by dipping back into an ice age on a millennial scale. dave s' quote seems to back up the latter interpretation.

[I dubious that Lamb himself did much work on the issue, or held particularly strong views on it. Most of his work was far more basic: building up records. Though to be honest I've read very little of what he did, because it isn't very relevant any more, other than as historical interest. What you're seeing (as in most reporting of GW stuff) is people taking an interest in the eye-catching stuff -W]

There is actually a good reason why someone might have switched to an expectation of warming in the 60s/70s. Prior to 1960 CO2 concentration had increased by about 30ppm over 150 years, a typical annual increase over the past few decades being ~0.4ppm with little sign of acceleration. That's not going to deliver a rapid warming to cancel out any (imagined?) cooling impulse. Presumably people wouldn't have had access to the wealth of ice core CO2 data we have today, but there seems to have been some appreciation of how much atmospheric CO2 was increasing: I think Arrhenius was writing at the beginning of the 20th Century about the possibility of CO2 doubling over the course of 1000 years.

With the Mauna Loa data being published, from 1960 people would have seen a clear acceleration in CO2 concentration, going from about 0.5ppm/yr to 1ppm/yr over little more than a decade. This development would have presumably brought to light the possibility of CO2 doubling on the scale of a single century.

"For instance, Lamb’s prediction ... was based on, essentially, a crude Fourier analysis (best fits of sinusoidal curves to his record). Since one of the dominant features was a rapid rise over the last century, the *presumption* of a cyclical nature of the record forced a prediction of a rapid cooling *precisely because there had been a recent rapid warming*. And although the niceties of periodograms had all been worked out by that time, Lamb seemed blissfully ignorant of the need to take particular care when fitting sinusoids to a record with significant information at its termination."

This sounds quite funny. It might not be deliberate, but Fourier analysis described as "fitting sinusoids" wow! how 19th Century. Yes it is taught that way, or was, but really ... that has no impact at all on whether a model moved from time to frequency domain (or vice versa) goes up or down.

It has no real bearing on what you are writing about but struck me as almost psuedo-sciency or something, and it lowered my respect for the writer. There is no presumption of a cyclical nature in Fourier Analysis beyond the crude simple introductory descriptions. Of course one needs to take end point conditions into account for anything.

Again, in that field at that time the comment may be to the point, but the way it is said is somewhat amusing.

[The text I've quoted is correct. Try reading it again, and perhaps try asking someone who understand FA if you still don't understand -W]

Difficult to understand the point of your post Markk. It's true that there is no necessary "presumption of a cyclical nature in Fourier Analysis" – after all Fourier analysis is a mathematical transformation which can be applied to any old time domain series to one’s heart's content. However if you apply FA to a time-domain signal to pull out its frequency components, and there isn't any sinusoidal variability (apparent or hidden) in the time domain, then you ain't going to pull out any frequency components! Now maybe your initial aim is to assess whether any dominant frequencies actually exist, in which case a Fourier transform without the presumption of cyclical variability is dandy. However if one's aim is to use frequency components of a time series predictively (e.g. to infer whether temperature is going to go up or down at some point in the future), then the "presumption of a cyclical nature" is rather implicit, wouldn't you say?

William, what is the point of this post?. Is it the pre-motivator for the next deletion exercise on wiki? What possible motivator is there otherwise?
Are you afraid that he might be right?

[PAs deleted. Warning: I'll get bored of cleaning up your mess eventually and just Burrow you -W]

Are you convinced that said (deceased ) person unable to defend himself is fair game and therefore the perfect subject to demonise and in so doing increase your obvious craving for fame and notoriety.....Just asking

bushy, do you hate the adoration of the lamb because you are an ipcc affiliate or a denier of cagw

Sort of like you in a perverted don't have a clue what drives you kind of thing. Sort of extraterrestrial king of weird.

What are you on about Kai?

bushy, I expect Dr. Lamb would be quite satisfied to see his work properly represented and put in context with current knowledge. In fact he would likely be properly pissed off with the pathetic attempts to use his old data to pursue non-scientific pseudo-"analyses" . Your concern trolling is first class, but I don’t think you’re going to sell the notion that an informed description of some of Lamb's analyses in proper context is "demonising"!

You may not understand science and scientists very well but they really hate to have their work misrepresented. Personally I find it maddening when papers of mine are cited to “support” a statement that bears little relation to what we actually showed/said in our paper...and I'm not even "deceased" yet.

The sad fact is that there are some creepy individuals that pursue misrepresentation of science and one of the sickening things these might do is to pretend that very old work (often from the currently "deceased") supports their dodgy agenda. A good example is the rather foolish reinterpretation of the early efforts to measure atmospheric CO2. The likes of Dr. Kreutz in Giessen knew perfectly well, for example, that the very high local [CO2] measures he made were the result of (inter alia) local industrial sources, and he’d be equally naffed to find that some dubious characters misrepresent his work to pretend that atmospheric CO2 levels were very high in the 1940s.

It is nice to represent the work of others properly, “deceased” or not. It's difficult to understand your antipathy to that…

Shit scared as usual of answering anything of substance.

"The sad fact is that there are some creepy individuals that pursue misrepresentation of science and one of the sickening things these might do is to pretend that very old work (often from the currently “deceased”) supports their dodgy agenda."
Hey Ho, now where does our old friend Svante August Arrhenius fit into all of this then?
Does this fit into YOUR dodgy agenda then?

bushy, I'm curious to know why you have a problem with the proper representation of a scientist's work in proper context. Can you give us a little bit of an explanation why that bothers you?

As for Arrhenius, surely his work speaks for itself. Outstanding and insightful, and rather astonishing to win a Nobel Prize for one element of his research while making some of the most insightful interpretations of experimental data that have ever been made in an entirely different field (aka "if the quantity of carbonic acid [CO2] increases in geometric progression, the augmentation of the temperature will increase nearly in arithmetic progression."

What's your particular problem with Arrhenius bushy?


the proper presentation of a scientists work in context? Sounds good to me. Take the Michael Mann graph of the MWP out of the IPCC reports and replace with H.H. Lamb's original graph.

[Why would anyone want to do that, if they were actually interested in the temperature history? You want to do it not because you value Lamb's work - you know nothing about it - but because you've been reading nonsense on denialist blogs -W]

Secondly, you continue to harp about increasing co2. Here's a hard fact in your eye [PA redacted - W]:

There are only 2 times in the past 600 million years when co2 levels have been this low. That would be the Carboniferous period and the Quaternary. Earth is below GAT and below average levels of atmospheric co2. [PA redacted -W]

[That rather depends on the timescales you're interested in, and the degree of uncertainty you're prepared to tolerate. See for example. The relevance of this is not entirely clear, however -W]

By Dr. Lumpus Spo… (not verified) on 12 Oct 2012 #permalink

Lumpy: "There are only 2 times in the past 600 million years when co2 levels have been this low. That would be the Carboniferous period and the Quaternary. Earth is below GAT and below average levels of atmospheric co2."

So you'd be happier in a world with the sea level 100 m higher?

“There are only 2 times in the past 600 million years when co2 levels have been this low. That would be the Carboniferous period and the Quaternary.”

Not sure of the relevance of that assertion in the context of this thread Lumpy (can you explain?), but you’re probably not correct anyway.

- We’re pretty confident (ice cores) that [CO2] levels haven’t been as high as current levels for at least the last 800,000 years.

- [CO2] levels were likely lower than current levels for much of the Pliocene, and certainly the later Pliocene from about 3.5 MYA to 2 MYA (see e.g. data compiled in Bartoli et al (2011) Paleoceanog. 26, PA4213)

- In fact it’s likely that current [CO2] levels are as high or higher than much of the entire period spanning backwards through the Quaternary and deep into the Pliocene.

- Indeed we’re likely above or already very close to [CO2] levels reaching right back to ~ 4.5 Mya (see e.g. data in Pagani et al (2010) Nature Geosci. 3, 27-30)

- Current [CO2] levels are around the level or higher than during the Early Miocene 20-25 MYA (see e.g. Pagani et al. (2011) Science 334, 1261-1264).

- There is evidence that atmospheric [CO2] levels were around present levels or lower during periods in the early and late Cretaceous where there is independent evidence for "cool greenhouse" conditions with high latitude glaciation (see e.g. Hong and Lee (2012) Earth Planet. Sci. Lett. 327, 23-28).

etc. etc.

Since you’re a “Dr.” Lumpy I expect you know that there’s a broad relationship between [CO2] levels and Earth temperature (much as bushy’s hero Svante Arrhenius understood). A major concern as gator has pointed out above is that there are [CO2] “thresholds” above which Greenland and Antarctic ice sheets aren’t viable. The evidence from correlations of the inception of N. hemisphere glaciation as [CO2] levels drifted down during the Pliocene, indicates that we’re probably already above the [CO2] threshold that would allow maintenance of the Greenland ice sheet (even though it will take a long time to melt).

P. S. I'm pleased that you enjoy my harping.

connoly said: "[Why would anyone want to do that, if they were actually interested in the temperature history? You want to do it not because you value Lamb's work - you know nothing about it - but because you've been reading nonsense on denialist blogs -W]"

wrong: "but because you've been reading nonsense on denialist blogs"

correct: "but because you've been reading nonsense on co2 climate hysteric blogs"!

bush is right: co2 warmist hallucinators praise the adoration of the lamb as proof that they are wrong


It's not easy to understand what you are attempting to convey since neither of you has articulated your problem very well. Can you clarify please?

In any case re Mann and Lamb, It’s obvious that as time progresses we update our understanding as the evidence base improves...yes? As we've seen on the couple of threads here, Lamb's schematic was based on a Central England time series with a final (averaged) temperature point around 1950, so apart from anything else it misses out a major chunk of anthropogenic greenhouse warming of the last 60 years.

Clearly if we're interested in the temperature change in response to rather large increases in greenhouse forcing one would prefer a more global scale analysis and that's what Mann's early papers provided (unfortunately limited to N. hemisphere), and so it's obviously preferable to use that analysis over a poorly defined schematic based on a highly localized time series truncated to miss out much of contemporary warming.

But we don't need to obsess over Mann's early analysis either since we now have around a dozen seperate N. hemisphere reconstructions with considerably ('though still deficient) more information of S. hemisphere temperatures. We can recognise that Mann's early original interpretations have pretty much held strong (last decade of 20th century likely warmest in the last millenium, current temperature anomalous in the context of the millenium), but that the last millenium has likely seen rather more temperature variability than was represented in the original analysis by Mann.

The evidence indicates that current temperatures (in the N hemisphere at least) are warmer than during the MWP. Even the attempt of Dr. Loehle to interpret proxy temperature data within a narrative of a warmer MWP, come up with an interpretation that the MWP might have reached the temperatures of the mid 20th century. But we’re already around 0.5- 0.6 oC warmer than that now (and more like 0.7 - 0.8 oC in the N. hemisphere). So even Dr. Loehle thinks that we’re warmer now (in the N hemisphere at least, ‘though Loehle considers his analysis to be “global”, even though it wasn't really global at all) than during the MWP.

What do you think kai/Lumpus?

"Take the ... Mann [et al.] graph out of the IPCC reports".

Chris has quite eloquently put the case into words, but I fear the photons "conveying" the words from the screen just pass through the eyes, hit the back of the brain case and reflect back out through the pupils, unimpeded throughout their entire journey.

They do say a picture paints a thousand words, so...

Go on then. Do take the Mann et al. plot out. It's the one labelled MBH1999 [droll, what!]. What are you left with? Phuket! More sodding hockey sticks.

Tell you what, take all those data out of that plot that in any way resemble a hockey stick. What's left? Why, it looks like the inside of some phud troll's empty brain case, that's what it looks like.

Quibble: "we now have around a dozen seperate N. hemisphere reconstructions" was true by 2006, there are more now so [as of 2010] we have around twenty seperate N. hemisphere reconstructions, all supporting the main conclusion that recent global temperatures are exceptionally warm.

Don't know if there are any more recent hemispherical or global reconstructions.

O.K., excellent quibbling dave s! Didn't actually sit down and count them, so used an "around a dozen" estimate from memory. I wasn't aware that there are around reconstructions now...

Plus lots of other work that supports those recons, e.g. many individual site records..

By Steve Bloom (not verified) on 14 Oct 2012 #permalink

Amusingly, while the Lamb was being adored at CA, useful work got done. People scrambled to find 1991-1996 examples of papers that supported Lamb in 1990 IPCC as MWP-big (global, synchronous, hot), but as Tom Curtis kept showing, the examples showed Lamb-like schematics that either were properly labeled regional, or had shrunken MWPs or were shown as approximations. Anyway, it was actually useful research, although results may not have provided the desired refutations when people actually read capttons/text, rather than just looking at related graphs.

By John Mashey (not verified) on 14 Oct 2012 #permalink


Thank you for the kind words.

Here's something I just found:

> Very few today realise that Lamb believed that this MWP was a period of warmth (and highpoint of post Roman European civilisation thus far) that mainly affected lands surrounding the Atlantic and surrounding lands (mid-latitudes). For NW Europe it must also have been a period of regular rainfall; good harvests require good watering. In his seminal book 'Climate, History and the Modern World' (Pages 171-172) Lamb also wrote that he didn't believe that this warm epoch had affected China or Japan, that its effects were mainly felt on the lands either side of the Atlantic and that he suspected that the Pacific cooled during this time. (He appears to have been right about the Pacific too; or at least partly so.)

Seems that in April 2010, our beloved Bishop's karaoke was not well rehearsed:

> More from the archives: this is a clipping from the Deseret News of Salt Lake City - the edition of 8th September 1972. It carries details of an interview with Hubert Lamb, the founder of the Climatic Research Unit, in which the great man discusses the impending ice age.…

William gets a cameo appearance.

[That one is good, because it combines quite a few of the std.memes. Lamb is speaking primarily of an observational trend - that's fine, it fits with what he is an expert in - and then extrapolates via an astronomical trend. That isn't fine, because the astronomical changes are too slow. But this is an area that Lamb very much isn't an expert in - see the quote from mt in this post. BH is well aware that Lamb isn't speaking of any peer-reviewed work. If, say, Mann were to say "I think the world is going to get warmer due to CO2, but I'll provide no evidence" then the likes of BH would be all over him. Lastly, of course, BH is very well aware of the location of my paper on this subject, but is too cowardly to provide his readers with a link to it.

Oh, but it gets better if you scroll down into the comments, say to "Lamb's position here is different. The piece quoted is not a scare story and I see little, if anything, that is baseless in the brief outline of the science" - they adore Lamb so much they just can't admit he was wrong -W]

Seems that I'm stepping in thingsbreak's footsteps:

> Lamb did not believe that the Medieval Climate Anomaly (or “Medieval Warm Epoch” as he originally called it) was a period of continuous temporally and spatially coherent global warming, but rather that it was more pronounced in the Atlantic Northern Hemisphere.…

Notice that Deming becomes "Darning".

An excerpt from an editorial in Pages, March 2011, by Elena Xoplaki, Dominik Fleitmann, and Henry F. Diaz:

> A large number of studies on the temporal and regional expression of the Medieval Warm Period for different parts
of the world have followed since the pioneering works of Lamb and LaMarche. A comprehensive review of those studies can be found in Hughes and Diaz (1994), Graham et al. (2010) and Diaz et al. (2011). The time frame is nowadays more commonly referred to as the Medieval
Climate Anomaly (MCA). This term was coined originally by Stine (1994), who sought an explanation for the results of
a wide-ranging geomorphic investigation of century-long low stands of lakes in the sub-tropical latitudes of western
North and South America. The subsequent adoption of this term reflects the availability of much more information
on the climate during medieval times since Lamb‘s pioneering studies.

(Searching for "Medieval Climate Anomaly" should lead to it quite easily.)

The reference Stine 1994 looks intriguing.

Here's the conclusion from Stine 1994, which is just a short note:

> Some workers, it seems, may have assumed a mythically stable California and Great Basin environment in their models of cultural change. We need look back only as far as the MCA to see how dramatically unstable that environment has actually been.

The adoration might be entering into a stage of change of faith:

> The idea that present temperatures are “unprecedented during the past several centuries” was definitely not original to the Mann hockey stick, as this view dated back to at least Hubert Lamb and could be said to be a consensus view.

Our good Bishop might need to revise his karaoke in the next edition of his political hit job.

Trying to get rid of something that does not change what could be said to be a consensus (?) view sounds perilous.

That the word "consensus" is entering into the jargon of the auditing sciences might be considered repugnant (tm -- auditing sciences) among their more orthodox practitionners.

Thanks Willard, in principle it's fair enough to point to a consensus of present temperatures “unprecedented during the past several centuries" as Lamb showed mid '60s temperatures unmatched back to around 1350, looking at the 7.1c graph.

The trouble arises with Montford's deceitful narrative.. (not a Bishop, he styles himself after one of the Lomond Hills or Paps of Fife, a secondary top called Bishop Hill which is noted for having Carlin Maggie attached. The witch Maggie was allegedly petrified by the Devil, no overt reference to Thatcher)

Anyway, Montford's epistle made a big fuss about MBH98 eliminating Lamb's sacred MWP, rather obviously bending the dates to imply that the MWP extended past 1400 to overlap MBH98. Looking at the stoat's overlay of figure 7.1c with MBH99, it's interesting to note that MBH actually shows warmer temps than Lamb between about 1380 and 1470.

Montford's forthcoming book seems to be all excited about the divergence problem, The Auditor rather implausibly claims that the "Hockey Team" explain the late 20th century dip in Briffa 2000 by saying it was "from a small geographically unrepresentative subset", how odd that The Auditor fails to tell his readers of the Briffa 1998 paper on the divergence problem.

Aha, an intriguing error by me: the allegation is about Briffa et al. 2001, not Briffa 2000.

The 2000 paper was featured in the TAR graph, which is what I think all the fuss about divergence not being shown comes in. However, there's not much divergence in the Briffa 2000 graph of 'Northern' Chronology Average, obtainable from CRU along with the abstract of the paper.

The Briffa et al. 2001 paper features in AR4 fig. 6.10b as BOS..2001. The text describes the divergence problem and states that "Briffa et al. (2001) specifically excluded the post-1960 data in their calibration against instrumental records, to avoid biasing the estimation of the earlier reconstructions (hence they are not shown in Figure 6.10)".

So much for The Auditor's allegation that "in order not to “dilute the message” in IPCC TAR, climate scientists chose to “hide the decline”, by simply deleting adverse data that went down." Wonder if he got his Briffa's mixed up, or is he just trying to confuse his readers?

dave s,

Thank you for the historical details.

I believe that I can echo this:

> So much for The Auditor’s allegation that “in order not to “dilute the message” in IPCC TAR.

So much for The Auditor's allegation that you need to trick to sell the "unprecedented" bit, more so if we consider, as you do, that "MBH actually shows warmer temps than Lamb between about 1380 and 1470."

Speaking of Bishop's fuss, here's an old comment from guest appearing John Hunter:

> You say “it’s pretty remarkable how seamlessly IPCC went from the 1990 graph to the Mann hockey stick”. Indeed it is, if you read the relevant sections of the 1990, 1995 and 2001 IPCC Assessments (but I appreciate that the contrarian promotional line conveniently ignores the 1995 Assessment). Don’t you think that it is a good thing that these discussions followed a reasonably steady developmental course rather than consisting of one single quantum leap from one belief to another?

Sounds like John Mashey's not alone. Nevertheless, the Auditor's response was not to say that this comment was "deranged":

> The comments that you quote from IPCC SAR are certainly on point. They seem to be based on Bradley and Jones [1993] and Hughes and Diaz [1994]. I agree that Jones, Bradley and Hughes have been at this much longer than Mann. I don’t think that the earlier studies are valid either. The history of the developing reliance on these very low-quality studies would be interesting to examine in detail.

The difference of tone in this exchange (many others between The Auditor and John Hunter are less cordial) and the one between Tom Curtis and CA was a bit different: the latter had more to do with hyenas hunting a rhinoceros than a dialog.

Notice also TCO's question resurrecting the thread:

> Just how good is that cartoony looking 1990 reconstruction that is often referred to?


Seems that the MWP gets a tough time, yet again. Notice the minimization of the GWFP:

> this is one result from one lake in an atypical location, a problem that even Lemonick had to acknowledge. “One possible criticism of the study is that it’s based on just one location,” he states. “Maybe this lake, or this region, was significantly cooler during the MPW for some reason than the rest of the world.” Yet this qualification did not diminish the headline hype: “So-Called Medieval Warm Period Not So Warm After All.”

Then notice the "Look, squirrel":

> But climate science is not such a cut and dried affair, where a single new paper from one isolated location can overturn five decades of research on the subject. Indeed, another paper [...]…

To adapt Eli Rabett's saying, a paper for a paper, a comment for a comment.


The last paragraph deserves to be quoted in full:

> Having put so much emphasis on the “unprecedented” nature of current global warming, the proponents of anthropogenic global warming just cannot back down from the hottest ever claim. The argument is that if the Medieval Warm Period was hotter then today’s temperatures are not anything special and the whole global warming crisis is just so much hokum. This means that skeptics are constantly searching for proof that things were hotter and true believers desperate to discredit that proof. This, my friends, is not a scientific argument, it is a political one, and it would not be so viciously defended by global warming proponents if their scientific case was not so fundamentally weak itself.

The argument is interesting, as the Auditor never really mentions it. Perhaps he does not because it rests on a fallacy. I'll leave it to readers to guess which one.


In the first quote, there is a link to the Medieval Warming Period Project:

I'm not sure if it's a comprehensive bibliography. And if not, where could we get one? The MWP sounds so much important, I should let go of sleeping altogether.